a3237d48a584e24ac5a2f12e637183d8f43cee5f
[sfrench/cifs-2.6.git] / drivers / char / synclink.c
1 /*
2  * linux/drivers/char/synclink.c
3  *
4  * $Id: synclink.c,v 4.38 2005/11/07 16:30:34 paulkf Exp $
5  *
6  * Device driver for Microgate SyncLink ISA and PCI
7  * high speed multiprotocol serial adapters.
8  *
9  * written by Paul Fulghum for Microgate Corporation
10  * paulkf@microgate.com
11  *
12  * Microgate and SyncLink are trademarks of Microgate Corporation
13  *
14  * Derived from serial.c written by Theodore Ts'o and Linus Torvalds
15  *
16  * Original release 01/11/99
17  *
18  * This code is released under the GNU General Public License (GPL)
19  *
20  * This driver is primarily intended for use in synchronous
21  * HDLC mode. Asynchronous mode is also provided.
22  *
23  * When operating in synchronous mode, each call to mgsl_write()
24  * contains exactly one complete HDLC frame. Calling mgsl_put_char
25  * will start assembling an HDLC frame that will not be sent until
26  * mgsl_flush_chars or mgsl_write is called.
27  * 
28  * Synchronous receive data is reported as complete frames. To accomplish
29  * this, the TTY flip buffer is bypassed (too small to hold largest
30  * frame and may fragment frames) and the line discipline
31  * receive entry point is called directly.
32  *
33  * This driver has been tested with a slightly modified ppp.c driver
34  * for synchronous PPP.
35  *
36  * 2000/02/16
37  * Added interface for syncppp.c driver (an alternate synchronous PPP
38  * implementation that also supports Cisco HDLC). Each device instance
39  * registers as a tty device AND a network device (if dosyncppp option
40  * is set for the device). The functionality is determined by which
41  * device interface is opened.
42  *
43  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
44  * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
45  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
46  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
47  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
48  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
49  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
50  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
51  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
52  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
53  * OF THE POSSIBILITY OF SUCH DAMAGE.
54  */
55
56 #if defined(__i386__)
57 #  define BREAKPOINT() asm("   int $3");
58 #else
59 #  define BREAKPOINT() { }
60 #endif
61
62 #define MAX_ISA_DEVICES 10
63 #define MAX_PCI_DEVICES 10
64 #define MAX_TOTAL_DEVICES 20
65
66 #include <linux/module.h>
67 #include <linux/errno.h>
68 #include <linux/signal.h>
69 #include <linux/sched.h>
70 #include <linux/timer.h>
71 #include <linux/interrupt.h>
72 #include <linux/pci.h>
73 #include <linux/tty.h>
74 #include <linux/tty_flip.h>
75 #include <linux/serial.h>
76 #include <linux/major.h>
77 #include <linux/string.h>
78 #include <linux/fcntl.h>
79 #include <linux/ptrace.h>
80 #include <linux/ioport.h>
81 #include <linux/mm.h>
82 #include <linux/slab.h>
83 #include <linux/delay.h>
84 #include <linux/netdevice.h>
85 #include <linux/vmalloc.h>
86 #include <linux/init.h>
87 #include <linux/ioctl.h>
88 #include <linux/synclink.h>
89
90 #include <asm/system.h>
91 #include <asm/io.h>
92 #include <asm/irq.h>
93 #include <asm/dma.h>
94 #include <linux/bitops.h>
95 #include <asm/types.h>
96 #include <linux/termios.h>
97 #include <linux/workqueue.h>
98 #include <linux/hdlc.h>
99 #include <linux/dma-mapping.h>
100
101 #if defined(CONFIG_HDLC) || (defined(CONFIG_HDLC_MODULE) && defined(CONFIG_SYNCLINK_MODULE))
102 #define SYNCLINK_GENERIC_HDLC 1
103 #else
104 #define SYNCLINK_GENERIC_HDLC 0
105 #endif
106
107 #define GET_USER(error,value,addr) error = get_user(value,addr)
108 #define COPY_FROM_USER(error,dest,src,size) error = copy_from_user(dest,src,size) ? -EFAULT : 0
109 #define PUT_USER(error,value,addr) error = put_user(value,addr)
110 #define COPY_TO_USER(error,dest,src,size) error = copy_to_user(dest,src,size) ? -EFAULT : 0
111
112 #include <asm/uaccess.h>
113
114 #define RCLRVALUE 0xffff
115
116 static MGSL_PARAMS default_params = {
117         MGSL_MODE_HDLC,                 /* unsigned long mode */
118         0,                              /* unsigned char loopback; */
119         HDLC_FLAG_UNDERRUN_ABORT15,     /* unsigned short flags; */
120         HDLC_ENCODING_NRZI_SPACE,       /* unsigned char encoding; */
121         0,                              /* unsigned long clock_speed; */
122         0xff,                           /* unsigned char addr_filter; */
123         HDLC_CRC_16_CCITT,              /* unsigned short crc_type; */
124         HDLC_PREAMBLE_LENGTH_8BITS,     /* unsigned char preamble_length; */
125         HDLC_PREAMBLE_PATTERN_NONE,     /* unsigned char preamble; */
126         9600,                           /* unsigned long data_rate; */
127         8,                              /* unsigned char data_bits; */
128         1,                              /* unsigned char stop_bits; */
129         ASYNC_PARITY_NONE               /* unsigned char parity; */
130 };
131
132 #define SHARED_MEM_ADDRESS_SIZE 0x40000
133 #define BUFFERLISTSIZE 4096
134 #define DMABUFFERSIZE 4096
135 #define MAXRXFRAMES 7
136
137 typedef struct _DMABUFFERENTRY
138 {
139         u32 phys_addr;  /* 32-bit flat physical address of data buffer */
140         volatile u16 count;     /* buffer size/data count */
141         volatile u16 status;    /* Control/status field */
142         volatile u16 rcc;       /* character count field */
143         u16 reserved;   /* padding required by 16C32 */
144         u32 link;       /* 32-bit flat link to next buffer entry */
145         char *virt_addr;        /* virtual address of data buffer */
146         u32 phys_entry; /* physical address of this buffer entry */
147         dma_addr_t dma_addr;
148 } DMABUFFERENTRY, *DMAPBUFFERENTRY;
149
150 /* The queue of BH actions to be performed */
151
152 #define BH_RECEIVE  1
153 #define BH_TRANSMIT 2
154 #define BH_STATUS   4
155
156 #define IO_PIN_SHUTDOWN_LIMIT 100
157
158 struct  _input_signal_events {
159         int     ri_up;  
160         int     ri_down;
161         int     dsr_up;
162         int     dsr_down;
163         int     dcd_up;
164         int     dcd_down;
165         int     cts_up;
166         int     cts_down;
167 };
168
169 /* transmit holding buffer definitions*/
170 #define MAX_TX_HOLDING_BUFFERS 5
171 struct tx_holding_buffer {
172         int     buffer_size;
173         unsigned char * buffer;
174 };
175
176
177 /*
178  * Device instance data structure
179  */
180  
181 struct mgsl_struct {
182         int                     magic;
183         int                     flags;
184         int                     count;          /* count of opens */
185         int                     line;
186         int                     hw_version;
187         unsigned short          close_delay;
188         unsigned short          closing_wait;   /* time to wait before closing */
189         
190         struct mgsl_icount      icount;
191         
192         struct tty_struct       *tty;
193         int                     timeout;
194         int                     x_char;         /* xon/xoff character */
195         int                     blocked_open;   /* # of blocked opens */
196         u16                     read_status_mask;
197         u16                     ignore_status_mask;     
198         unsigned char           *xmit_buf;
199         int                     xmit_head;
200         int                     xmit_tail;
201         int                     xmit_cnt;
202         
203         wait_queue_head_t       open_wait;
204         wait_queue_head_t       close_wait;
205         
206         wait_queue_head_t       status_event_wait_q;
207         wait_queue_head_t       event_wait_q;
208         struct timer_list       tx_timer;       /* HDLC transmit timeout timer */
209         struct mgsl_struct      *next_device;   /* device list link */
210         
211         spinlock_t irq_spinlock;                /* spinlock for synchronizing with ISR */
212         struct work_struct task;                /* task structure for scheduling bh */
213
214         u32 EventMask;                  /* event trigger mask */
215         u32 RecordedEvents;             /* pending events */
216
217         u32 max_frame_size;             /* as set by device config */
218
219         u32 pending_bh;
220
221         int bh_running;         /* Protection from multiple */
222         int isr_overflow;
223         int bh_requested;
224         
225         int dcd_chkcount;               /* check counts to prevent */
226         int cts_chkcount;               /* too many IRQs if a signal */
227         int dsr_chkcount;               /* is floating */
228         int ri_chkcount;
229
230         char *buffer_list;              /* virtual address of Rx & Tx buffer lists */
231         u32 buffer_list_phys;
232         dma_addr_t buffer_list_dma_addr;
233
234         unsigned int rx_buffer_count;   /* count of total allocated Rx buffers */
235         DMABUFFERENTRY *rx_buffer_list; /* list of receive buffer entries */
236         unsigned int current_rx_buffer;
237
238         int num_tx_dma_buffers;         /* number of tx dma frames required */
239         int tx_dma_buffers_used;
240         unsigned int tx_buffer_count;   /* count of total allocated Tx buffers */
241         DMABUFFERENTRY *tx_buffer_list; /* list of transmit buffer entries */
242         int start_tx_dma_buffer;        /* tx dma buffer to start tx dma operation */
243         int current_tx_buffer;          /* next tx dma buffer to be loaded */
244         
245         unsigned char *intermediate_rxbuffer;
246
247         int num_tx_holding_buffers;     /* number of tx holding buffer allocated */
248         int get_tx_holding_index;       /* next tx holding buffer for adapter to load */
249         int put_tx_holding_index;       /* next tx holding buffer to store user request */
250         int tx_holding_count;           /* number of tx holding buffers waiting */
251         struct tx_holding_buffer tx_holding_buffers[MAX_TX_HOLDING_BUFFERS];
252
253         int rx_enabled;
254         int rx_overflow;
255         int rx_rcc_underrun;
256
257         int tx_enabled;
258         int tx_active;
259         u32 idle_mode;
260
261         u16 cmr_value;
262         u16 tcsr_value;
263
264         char device_name[25];           /* device instance name */
265
266         unsigned int bus_type;  /* expansion bus type (ISA,EISA,PCI) */
267         unsigned char bus;              /* expansion bus number (zero based) */
268         unsigned char function;         /* PCI device number */
269
270         unsigned int io_base;           /* base I/O address of adapter */
271         unsigned int io_addr_size;      /* size of the I/O address range */
272         int io_addr_requested;          /* nonzero if I/O address requested */
273         
274         unsigned int irq_level;         /* interrupt level */
275         unsigned long irq_flags;
276         int irq_requested;              /* nonzero if IRQ requested */
277         
278         unsigned int dma_level;         /* DMA channel */
279         int dma_requested;              /* nonzero if dma channel requested */
280
281         u16 mbre_bit;
282         u16 loopback_bits;
283         u16 usc_idle_mode;
284
285         MGSL_PARAMS params;             /* communications parameters */
286
287         unsigned char serial_signals;   /* current serial signal states */
288
289         int irq_occurred;               /* for diagnostics use */
290         unsigned int init_error;        /* Initialization startup error                 (DIAGS) */
291         int     fDiagnosticsmode;       /* Driver in Diagnostic mode?                   (DIAGS) */
292
293         u32 last_mem_alloc;
294         unsigned char* memory_base;     /* shared memory address (PCI only) */
295         u32 phys_memory_base;
296         int shared_mem_requested;
297
298         unsigned char* lcr_base;        /* local config registers (PCI only) */
299         u32 phys_lcr_base;
300         u32 lcr_offset;
301         int lcr_mem_requested;
302
303         u32 misc_ctrl_value;
304         char flag_buf[MAX_ASYNC_BUFFER_SIZE];
305         char char_buf[MAX_ASYNC_BUFFER_SIZE];   
306         BOOLEAN drop_rts_on_tx_done;
307
308         BOOLEAN loopmode_insert_requested;
309         BOOLEAN loopmode_send_done_requested;
310         
311         struct  _input_signal_events    input_signal_events;
312
313         /* generic HDLC device parts */
314         int netcount;
315         int dosyncppp;
316         spinlock_t netlock;
317
318 #if SYNCLINK_GENERIC_HDLC
319         struct net_device *netdev;
320 #endif
321 };
322
323 #define MGSL_MAGIC 0x5401
324
325 /*
326  * The size of the serial xmit buffer is 1 page, or 4096 bytes
327  */
328 #ifndef SERIAL_XMIT_SIZE
329 #define SERIAL_XMIT_SIZE 4096
330 #endif
331
332 /*
333  * These macros define the offsets used in calculating the
334  * I/O address of the specified USC registers.
335  */
336
337
338 #define DCPIN 2         /* Bit 1 of I/O address */
339 #define SDPIN 4         /* Bit 2 of I/O address */
340
341 #define DCAR 0          /* DMA command/address register */
342 #define CCAR SDPIN              /* channel command/address register */
343 #define DATAREG DCPIN + SDPIN   /* serial data register */
344 #define MSBONLY 0x41
345 #define LSBONLY 0x40
346
347 /*
348  * These macros define the register address (ordinal number)
349  * used for writing address/value pairs to the USC.
350  */
351
352 #define CMR     0x02    /* Channel mode Register */
353 #define CCSR    0x04    /* Channel Command/status Register */
354 #define CCR     0x06    /* Channel Control Register */
355 #define PSR     0x08    /* Port status Register */
356 #define PCR     0x0a    /* Port Control Register */
357 #define TMDR    0x0c    /* Test mode Data Register */
358 #define TMCR    0x0e    /* Test mode Control Register */
359 #define CMCR    0x10    /* Clock mode Control Register */
360 #define HCR     0x12    /* Hardware Configuration Register */
361 #define IVR     0x14    /* Interrupt Vector Register */
362 #define IOCR    0x16    /* Input/Output Control Register */
363 #define ICR     0x18    /* Interrupt Control Register */
364 #define DCCR    0x1a    /* Daisy Chain Control Register */
365 #define MISR    0x1c    /* Misc Interrupt status Register */
366 #define SICR    0x1e    /* status Interrupt Control Register */
367 #define RDR     0x20    /* Receive Data Register */
368 #define RMR     0x22    /* Receive mode Register */
369 #define RCSR    0x24    /* Receive Command/status Register */
370 #define RICR    0x26    /* Receive Interrupt Control Register */
371 #define RSR     0x28    /* Receive Sync Register */
372 #define RCLR    0x2a    /* Receive count Limit Register */
373 #define RCCR    0x2c    /* Receive Character count Register */
374 #define TC0R    0x2e    /* Time Constant 0 Register */
375 #define TDR     0x30    /* Transmit Data Register */
376 #define TMR     0x32    /* Transmit mode Register */
377 #define TCSR    0x34    /* Transmit Command/status Register */
378 #define TICR    0x36    /* Transmit Interrupt Control Register */
379 #define TSR     0x38    /* Transmit Sync Register */
380 #define TCLR    0x3a    /* Transmit count Limit Register */
381 #define TCCR    0x3c    /* Transmit Character count Register */
382 #define TC1R    0x3e    /* Time Constant 1 Register */
383
384
385 /*
386  * MACRO DEFINITIONS FOR DMA REGISTERS
387  */
388
389 #define DCR     0x06    /* DMA Control Register (shared) */
390 #define DACR    0x08    /* DMA Array count Register (shared) */
391 #define BDCR    0x12    /* Burst/Dwell Control Register (shared) */
392 #define DIVR    0x14    /* DMA Interrupt Vector Register (shared) */    
393 #define DICR    0x18    /* DMA Interrupt Control Register (shared) */
394 #define CDIR    0x1a    /* Clear DMA Interrupt Register (shared) */
395 #define SDIR    0x1c    /* Set DMA Interrupt Register (shared) */
396
397 #define TDMR    0x02    /* Transmit DMA mode Register */
398 #define TDIAR   0x1e    /* Transmit DMA Interrupt Arm Register */
399 #define TBCR    0x2a    /* Transmit Byte count Register */
400 #define TARL    0x2c    /* Transmit Address Register (low) */
401 #define TARU    0x2e    /* Transmit Address Register (high) */
402 #define NTBCR   0x3a    /* Next Transmit Byte count Register */
403 #define NTARL   0x3c    /* Next Transmit Address Register (low) */
404 #define NTARU   0x3e    /* Next Transmit Address Register (high) */
405
406 #define RDMR    0x82    /* Receive DMA mode Register (non-shared) */
407 #define RDIAR   0x9e    /* Receive DMA Interrupt Arm Register */
408 #define RBCR    0xaa    /* Receive Byte count Register */
409 #define RARL    0xac    /* Receive Address Register (low) */
410 #define RARU    0xae    /* Receive Address Register (high) */
411 #define NRBCR   0xba    /* Next Receive Byte count Register */
412 #define NRARL   0xbc    /* Next Receive Address Register (low) */
413 #define NRARU   0xbe    /* Next Receive Address Register (high) */
414
415
416 /*
417  * MACRO DEFINITIONS FOR MODEM STATUS BITS
418  */
419
420 #define MODEMSTATUS_DTR 0x80
421 #define MODEMSTATUS_DSR 0x40
422 #define MODEMSTATUS_RTS 0x20
423 #define MODEMSTATUS_CTS 0x10
424 #define MODEMSTATUS_RI  0x04
425 #define MODEMSTATUS_DCD 0x01
426
427
428 /*
429  * Channel Command/Address Register (CCAR) Command Codes
430  */
431
432 #define RTCmd_Null                      0x0000
433 #define RTCmd_ResetHighestIus           0x1000
434 #define RTCmd_TriggerChannelLoadDma     0x2000
435 #define RTCmd_TriggerRxDma              0x2800
436 #define RTCmd_TriggerTxDma              0x3000
437 #define RTCmd_TriggerRxAndTxDma         0x3800
438 #define RTCmd_PurgeRxFifo               0x4800
439 #define RTCmd_PurgeTxFifo               0x5000
440 #define RTCmd_PurgeRxAndTxFifo          0x5800
441 #define RTCmd_LoadRcc                   0x6800
442 #define RTCmd_LoadTcc                   0x7000
443 #define RTCmd_LoadRccAndTcc             0x7800
444 #define RTCmd_LoadTC0                   0x8800
445 #define RTCmd_LoadTC1                   0x9000
446 #define RTCmd_LoadTC0AndTC1             0x9800
447 #define RTCmd_SerialDataLSBFirst        0xa000
448 #define RTCmd_SerialDataMSBFirst        0xa800
449 #define RTCmd_SelectBigEndian           0xb000
450 #define RTCmd_SelectLittleEndian        0xb800
451
452
453 /*
454  * DMA Command/Address Register (DCAR) Command Codes
455  */
456
457 #define DmaCmd_Null                     0x0000
458 #define DmaCmd_ResetTxChannel           0x1000
459 #define DmaCmd_ResetRxChannel           0x1200
460 #define DmaCmd_StartTxChannel           0x2000
461 #define DmaCmd_StartRxChannel           0x2200
462 #define DmaCmd_ContinueTxChannel        0x3000
463 #define DmaCmd_ContinueRxChannel        0x3200
464 #define DmaCmd_PauseTxChannel           0x4000
465 #define DmaCmd_PauseRxChannel           0x4200
466 #define DmaCmd_AbortTxChannel           0x5000
467 #define DmaCmd_AbortRxChannel           0x5200
468 #define DmaCmd_InitTxChannel            0x7000
469 #define DmaCmd_InitRxChannel            0x7200
470 #define DmaCmd_ResetHighestDmaIus       0x8000
471 #define DmaCmd_ResetAllChannels         0x9000
472 #define DmaCmd_StartAllChannels         0xa000
473 #define DmaCmd_ContinueAllChannels      0xb000
474 #define DmaCmd_PauseAllChannels         0xc000
475 #define DmaCmd_AbortAllChannels         0xd000
476 #define DmaCmd_InitAllChannels          0xf000
477
478 #define TCmd_Null                       0x0000
479 #define TCmd_ClearTxCRC                 0x2000
480 #define TCmd_SelectTicrTtsaData         0x4000
481 #define TCmd_SelectTicrTxFifostatus     0x5000
482 #define TCmd_SelectTicrIntLevel         0x6000
483 #define TCmd_SelectTicrdma_level                0x7000
484 #define TCmd_SendFrame                  0x8000
485 #define TCmd_SendAbort                  0x9000
486 #define TCmd_EnableDleInsertion         0xc000
487 #define TCmd_DisableDleInsertion        0xd000
488 #define TCmd_ClearEofEom                0xe000
489 #define TCmd_SetEofEom                  0xf000
490
491 #define RCmd_Null                       0x0000
492 #define RCmd_ClearRxCRC                 0x2000
493 #define RCmd_EnterHuntmode              0x3000
494 #define RCmd_SelectRicrRtsaData         0x4000
495 #define RCmd_SelectRicrRxFifostatus     0x5000
496 #define RCmd_SelectRicrIntLevel         0x6000
497 #define RCmd_SelectRicrdma_level                0x7000
498
499 /*
500  * Bits for enabling and disabling IRQs in Interrupt Control Register (ICR)
501  */
502  
503 #define RECEIVE_STATUS          BIT5
504 #define RECEIVE_DATA            BIT4
505 #define TRANSMIT_STATUS         BIT3
506 #define TRANSMIT_DATA           BIT2
507 #define IO_PIN                  BIT1
508 #define MISC                    BIT0
509
510
511 /*
512  * Receive status Bits in Receive Command/status Register RCSR
513  */
514
515 #define RXSTATUS_SHORT_FRAME            BIT8
516 #define RXSTATUS_CODE_VIOLATION         BIT8
517 #define RXSTATUS_EXITED_HUNT            BIT7
518 #define RXSTATUS_IDLE_RECEIVED          BIT6
519 #define RXSTATUS_BREAK_RECEIVED         BIT5
520 #define RXSTATUS_ABORT_RECEIVED         BIT5
521 #define RXSTATUS_RXBOUND                BIT4
522 #define RXSTATUS_CRC_ERROR              BIT3
523 #define RXSTATUS_FRAMING_ERROR          BIT3
524 #define RXSTATUS_ABORT                  BIT2
525 #define RXSTATUS_PARITY_ERROR           BIT2
526 #define RXSTATUS_OVERRUN                BIT1
527 #define RXSTATUS_DATA_AVAILABLE         BIT0
528 #define RXSTATUS_ALL                    0x01f6
529 #define usc_UnlatchRxstatusBits(a,b) usc_OutReg( (a), RCSR, (u16)((b) & RXSTATUS_ALL) )
530
531 /*
532  * Values for setting transmit idle mode in 
533  * Transmit Control/status Register (TCSR)
534  */
535 #define IDLEMODE_FLAGS                  0x0000
536 #define IDLEMODE_ALT_ONE_ZERO           0x0100
537 #define IDLEMODE_ZERO                   0x0200
538 #define IDLEMODE_ONE                    0x0300
539 #define IDLEMODE_ALT_MARK_SPACE         0x0500
540 #define IDLEMODE_SPACE                  0x0600
541 #define IDLEMODE_MARK                   0x0700
542 #define IDLEMODE_MASK                   0x0700
543
544 /*
545  * IUSC revision identifiers
546  */
547 #define IUSC_SL1660                     0x4d44
548 #define IUSC_PRE_SL1660                 0x4553
549
550 /*
551  * Transmit status Bits in Transmit Command/status Register (TCSR)
552  */
553
554 #define TCSR_PRESERVE                   0x0F00
555
556 #define TCSR_UNDERWAIT                  BIT11
557 #define TXSTATUS_PREAMBLE_SENT          BIT7
558 #define TXSTATUS_IDLE_SENT              BIT6
559 #define TXSTATUS_ABORT_SENT             BIT5
560 #define TXSTATUS_EOF_SENT               BIT4
561 #define TXSTATUS_EOM_SENT               BIT4
562 #define TXSTATUS_CRC_SENT               BIT3
563 #define TXSTATUS_ALL_SENT               BIT2
564 #define TXSTATUS_UNDERRUN               BIT1
565 #define TXSTATUS_FIFO_EMPTY             BIT0
566 #define TXSTATUS_ALL                    0x00fa
567 #define usc_UnlatchTxstatusBits(a,b) usc_OutReg( (a), TCSR, (u16)((a)->tcsr_value + ((b) & 0x00FF)) )
568                                 
569
570 #define MISCSTATUS_RXC_LATCHED          BIT15
571 #define MISCSTATUS_RXC                  BIT14
572 #define MISCSTATUS_TXC_LATCHED          BIT13
573 #define MISCSTATUS_TXC                  BIT12
574 #define MISCSTATUS_RI_LATCHED           BIT11
575 #define MISCSTATUS_RI                   BIT10
576 #define MISCSTATUS_DSR_LATCHED          BIT9
577 #define MISCSTATUS_DSR                  BIT8
578 #define MISCSTATUS_DCD_LATCHED          BIT7
579 #define MISCSTATUS_DCD                  BIT6
580 #define MISCSTATUS_CTS_LATCHED          BIT5
581 #define MISCSTATUS_CTS                  BIT4
582 #define MISCSTATUS_RCC_UNDERRUN         BIT3
583 #define MISCSTATUS_DPLL_NO_SYNC         BIT2
584 #define MISCSTATUS_BRG1_ZERO            BIT1
585 #define MISCSTATUS_BRG0_ZERO            BIT0
586
587 #define usc_UnlatchIostatusBits(a,b) usc_OutReg((a),MISR,(u16)((b) & 0xaaa0))
588 #define usc_UnlatchMiscstatusBits(a,b) usc_OutReg((a),MISR,(u16)((b) & 0x000f))
589
590 #define SICR_RXC_ACTIVE                 BIT15
591 #define SICR_RXC_INACTIVE               BIT14
592 #define SICR_RXC                        (BIT15+BIT14)
593 #define SICR_TXC_ACTIVE                 BIT13
594 #define SICR_TXC_INACTIVE               BIT12
595 #define SICR_TXC                        (BIT13+BIT12)
596 #define SICR_RI_ACTIVE                  BIT11
597 #define SICR_RI_INACTIVE                BIT10
598 #define SICR_RI                         (BIT11+BIT10)
599 #define SICR_DSR_ACTIVE                 BIT9
600 #define SICR_DSR_INACTIVE               BIT8
601 #define SICR_DSR                        (BIT9+BIT8)
602 #define SICR_DCD_ACTIVE                 BIT7
603 #define SICR_DCD_INACTIVE               BIT6
604 #define SICR_DCD                        (BIT7+BIT6)
605 #define SICR_CTS_ACTIVE                 BIT5
606 #define SICR_CTS_INACTIVE               BIT4
607 #define SICR_CTS                        (BIT5+BIT4)
608 #define SICR_RCC_UNDERFLOW              BIT3
609 #define SICR_DPLL_NO_SYNC               BIT2
610 #define SICR_BRG1_ZERO                  BIT1
611 #define SICR_BRG0_ZERO                  BIT0
612
613 void usc_DisableMasterIrqBit( struct mgsl_struct *info );
614 void usc_EnableMasterIrqBit( struct mgsl_struct *info );
615 void usc_EnableInterrupts( struct mgsl_struct *info, u16 IrqMask );
616 void usc_DisableInterrupts( struct mgsl_struct *info, u16 IrqMask );
617 void usc_ClearIrqPendingBits( struct mgsl_struct *info, u16 IrqMask );
618
619 #define usc_EnableInterrupts( a, b ) \
620         usc_OutReg( (a), ICR, (u16)((usc_InReg((a),ICR) & 0xff00) + 0xc0 + (b)) )
621
622 #define usc_DisableInterrupts( a, b ) \
623         usc_OutReg( (a), ICR, (u16)((usc_InReg((a),ICR) & 0xff00) + 0x80 + (b)) )
624
625 #define usc_EnableMasterIrqBit(a) \
626         usc_OutReg( (a), ICR, (u16)((usc_InReg((a),ICR) & 0x0f00) + 0xb000) )
627
628 #define usc_DisableMasterIrqBit(a) \
629         usc_OutReg( (a), ICR, (u16)(usc_InReg((a),ICR) & 0x7f00) )
630
631 #define usc_ClearIrqPendingBits( a, b ) usc_OutReg( (a), DCCR, 0x40 + (b) )
632
633 /*
634  * Transmit status Bits in Transmit Control status Register (TCSR)
635  * and Transmit Interrupt Control Register (TICR) (except BIT2, BIT0)
636  */
637
638 #define TXSTATUS_PREAMBLE_SENT  BIT7
639 #define TXSTATUS_IDLE_SENT      BIT6
640 #define TXSTATUS_ABORT_SENT     BIT5
641 #define TXSTATUS_EOF            BIT4
642 #define TXSTATUS_CRC_SENT       BIT3
643 #define TXSTATUS_ALL_SENT       BIT2
644 #define TXSTATUS_UNDERRUN       BIT1
645 #define TXSTATUS_FIFO_EMPTY     BIT0
646
647 #define DICR_MASTER             BIT15
648 #define DICR_TRANSMIT           BIT0
649 #define DICR_RECEIVE            BIT1
650
651 #define usc_EnableDmaInterrupts(a,b) \
652         usc_OutDmaReg( (a), DICR, (u16)(usc_InDmaReg((a),DICR) | (b)) )
653
654 #define usc_DisableDmaInterrupts(a,b) \
655         usc_OutDmaReg( (a), DICR, (u16)(usc_InDmaReg((a),DICR) & ~(b)) )
656
657 #define usc_EnableStatusIrqs(a,b) \
658         usc_OutReg( (a), SICR, (u16)(usc_InReg((a),SICR) | (b)) )
659
660 #define usc_DisablestatusIrqs(a,b) \
661         usc_OutReg( (a), SICR, (u16)(usc_InReg((a),SICR) & ~(b)) )
662
663 /* Transmit status Bits in Transmit Control status Register (TCSR) */
664 /* and Transmit Interrupt Control Register (TICR) (except BIT2, BIT0) */
665
666
667 #define DISABLE_UNCONDITIONAL    0
668 #define DISABLE_END_OF_FRAME     1
669 #define ENABLE_UNCONDITIONAL     2
670 #define ENABLE_AUTO_CTS          3
671 #define ENABLE_AUTO_DCD          3
672 #define usc_EnableTransmitter(a,b) \
673         usc_OutReg( (a), TMR, (u16)((usc_InReg((a),TMR) & 0xfffc) | (b)) )
674 #define usc_EnableReceiver(a,b) \
675         usc_OutReg( (a), RMR, (u16)((usc_InReg((a),RMR) & 0xfffc) | (b)) )
676
677 static u16  usc_InDmaReg( struct mgsl_struct *info, u16 Port );
678 static void usc_OutDmaReg( struct mgsl_struct *info, u16 Port, u16 Value );
679 static void usc_DmaCmd( struct mgsl_struct *info, u16 Cmd );
680
681 static u16  usc_InReg( struct mgsl_struct *info, u16 Port );
682 static void usc_OutReg( struct mgsl_struct *info, u16 Port, u16 Value );
683 static void usc_RTCmd( struct mgsl_struct *info, u16 Cmd );
684 void usc_RCmd( struct mgsl_struct *info, u16 Cmd );
685 void usc_TCmd( struct mgsl_struct *info, u16 Cmd );
686
687 #define usc_TCmd(a,b) usc_OutReg((a), TCSR, (u16)((a)->tcsr_value + (b)))
688 #define usc_RCmd(a,b) usc_OutReg((a), RCSR, (b))
689
690 #define usc_SetTransmitSyncChars(a,s0,s1) usc_OutReg((a), TSR, (u16)(((u16)s0<<8)|(u16)s1))
691
692 static void usc_process_rxoverrun_sync( struct mgsl_struct *info );
693 static void usc_start_receiver( struct mgsl_struct *info );
694 static void usc_stop_receiver( struct mgsl_struct *info );
695
696 static void usc_start_transmitter( struct mgsl_struct *info );
697 static void usc_stop_transmitter( struct mgsl_struct *info );
698 static void usc_set_txidle( struct mgsl_struct *info );
699 static void usc_load_txfifo( struct mgsl_struct *info );
700
701 static void usc_enable_aux_clock( struct mgsl_struct *info, u32 DataRate );
702 static void usc_enable_loopback( struct mgsl_struct *info, int enable );
703
704 static void usc_get_serial_signals( struct mgsl_struct *info );
705 static void usc_set_serial_signals( struct mgsl_struct *info );
706
707 static void usc_reset( struct mgsl_struct *info );
708
709 static void usc_set_sync_mode( struct mgsl_struct *info );
710 static void usc_set_sdlc_mode( struct mgsl_struct *info );
711 static void usc_set_async_mode( struct mgsl_struct *info );
712 static void usc_enable_async_clock( struct mgsl_struct *info, u32 DataRate );
713
714 static void usc_loopback_frame( struct mgsl_struct *info );
715
716 static void mgsl_tx_timeout(unsigned long context);
717
718
719 static void usc_loopmode_cancel_transmit( struct mgsl_struct * info );
720 static void usc_loopmode_insert_request( struct mgsl_struct * info );
721 static int usc_loopmode_active( struct mgsl_struct * info);
722 static void usc_loopmode_send_done( struct mgsl_struct * info );
723
724 static int mgsl_ioctl_common(struct mgsl_struct *info, unsigned int cmd, unsigned long arg);
725
726 #if SYNCLINK_GENERIC_HDLC
727 #define dev_to_port(D) (dev_to_hdlc(D)->priv)
728 static void hdlcdev_tx_done(struct mgsl_struct *info);
729 static void hdlcdev_rx(struct mgsl_struct *info, char *buf, int size);
730 static int  hdlcdev_init(struct mgsl_struct *info);
731 static void hdlcdev_exit(struct mgsl_struct *info);
732 #endif
733
734 /*
735  * Defines a BUS descriptor value for the PCI adapter
736  * local bus address ranges.
737  */
738
739 #define BUS_DESCRIPTOR( WrHold, WrDly, RdDly, Nwdd, Nwad, Nxda, Nrdd, Nrad ) \
740 (0x00400020 + \
741 ((WrHold) << 30) + \
742 ((WrDly)  << 28) + \
743 ((RdDly)  << 26) + \
744 ((Nwdd)   << 20) + \
745 ((Nwad)   << 15) + \
746 ((Nxda)   << 13) + \
747 ((Nrdd)   << 11) + \
748 ((Nrad)   <<  6) )
749
750 static void mgsl_trace_block(struct mgsl_struct *info,const char* data, int count, int xmit);
751
752 /*
753  * Adapter diagnostic routines
754  */
755 static BOOLEAN mgsl_register_test( struct mgsl_struct *info );
756 static BOOLEAN mgsl_irq_test( struct mgsl_struct *info );
757 static BOOLEAN mgsl_dma_test( struct mgsl_struct *info );
758 static BOOLEAN mgsl_memory_test( struct mgsl_struct *info );
759 static int mgsl_adapter_test( struct mgsl_struct *info );
760
761 /*
762  * device and resource management routines
763  */
764 static int mgsl_claim_resources(struct mgsl_struct *info);
765 static void mgsl_release_resources(struct mgsl_struct *info);
766 static void mgsl_add_device(struct mgsl_struct *info);
767 static struct mgsl_struct* mgsl_allocate_device(void);
768
769 /*
770  * DMA buffer manupulation functions.
771  */
772 static void mgsl_free_rx_frame_buffers( struct mgsl_struct *info, unsigned int StartIndex, unsigned int EndIndex );
773 static int  mgsl_get_rx_frame( struct mgsl_struct *info );
774 static int  mgsl_get_raw_rx_frame( struct mgsl_struct *info );
775 static void mgsl_reset_rx_dma_buffers( struct mgsl_struct *info );
776 static void mgsl_reset_tx_dma_buffers( struct mgsl_struct *info );
777 static int num_free_tx_dma_buffers(struct mgsl_struct *info);
778 static void mgsl_load_tx_dma_buffer( struct mgsl_struct *info, const char *Buffer, unsigned int BufferSize);
779 static void mgsl_load_pci_memory(char* TargetPtr, const char* SourcePtr, unsigned short count);
780
781 /*
782  * DMA and Shared Memory buffer allocation and formatting
783  */
784 static int  mgsl_allocate_dma_buffers(struct mgsl_struct *info);
785 static void mgsl_free_dma_buffers(struct mgsl_struct *info);
786 static int  mgsl_alloc_frame_memory(struct mgsl_struct *info, DMABUFFERENTRY *BufferList,int Buffercount);
787 static void mgsl_free_frame_memory(struct mgsl_struct *info, DMABUFFERENTRY *BufferList,int Buffercount);
788 static int  mgsl_alloc_buffer_list_memory(struct mgsl_struct *info);
789 static void mgsl_free_buffer_list_memory(struct mgsl_struct *info);
790 static int mgsl_alloc_intermediate_rxbuffer_memory(struct mgsl_struct *info);
791 static void mgsl_free_intermediate_rxbuffer_memory(struct mgsl_struct *info);
792 static int mgsl_alloc_intermediate_txbuffer_memory(struct mgsl_struct *info);
793 static void mgsl_free_intermediate_txbuffer_memory(struct mgsl_struct *info);
794 static int load_next_tx_holding_buffer(struct mgsl_struct *info);
795 static int save_tx_buffer_request(struct mgsl_struct *info,const char *Buffer, unsigned int BufferSize);
796
797 /*
798  * Bottom half interrupt handlers
799  */
800 static void mgsl_bh_handler(struct work_struct *work);
801 static void mgsl_bh_receive(struct mgsl_struct *info);
802 static void mgsl_bh_transmit(struct mgsl_struct *info);
803 static void mgsl_bh_status(struct mgsl_struct *info);
804
805 /*
806  * Interrupt handler routines and dispatch table.
807  */
808 static void mgsl_isr_null( struct mgsl_struct *info );
809 static void mgsl_isr_transmit_data( struct mgsl_struct *info );
810 static void mgsl_isr_receive_data( struct mgsl_struct *info );
811 static void mgsl_isr_receive_status( struct mgsl_struct *info );
812 static void mgsl_isr_transmit_status( struct mgsl_struct *info );
813 static void mgsl_isr_io_pin( struct mgsl_struct *info );
814 static void mgsl_isr_misc( struct mgsl_struct *info );
815 static void mgsl_isr_receive_dma( struct mgsl_struct *info );
816 static void mgsl_isr_transmit_dma( struct mgsl_struct *info );
817
818 typedef void (*isr_dispatch_func)(struct mgsl_struct *);
819
820 static isr_dispatch_func UscIsrTable[7] =
821 {
822         mgsl_isr_null,
823         mgsl_isr_misc,
824         mgsl_isr_io_pin,
825         mgsl_isr_transmit_data,
826         mgsl_isr_transmit_status,
827         mgsl_isr_receive_data,
828         mgsl_isr_receive_status
829 };
830
831 /*
832  * ioctl call handlers
833  */
834 static int tiocmget(struct tty_struct *tty, struct file *file);
835 static int tiocmset(struct tty_struct *tty, struct file *file,
836                     unsigned int set, unsigned int clear);
837 static int mgsl_get_stats(struct mgsl_struct * info, struct mgsl_icount
838         __user *user_icount);
839 static int mgsl_get_params(struct mgsl_struct * info, MGSL_PARAMS  __user *user_params);
840 static int mgsl_set_params(struct mgsl_struct * info, MGSL_PARAMS  __user *new_params);
841 static int mgsl_get_txidle(struct mgsl_struct * info, int __user *idle_mode);
842 static int mgsl_set_txidle(struct mgsl_struct * info, int idle_mode);
843 static int mgsl_txenable(struct mgsl_struct * info, int enable);
844 static int mgsl_txabort(struct mgsl_struct * info);
845 static int mgsl_rxenable(struct mgsl_struct * info, int enable);
846 static int mgsl_wait_event(struct mgsl_struct * info, int __user *mask);
847 static int mgsl_loopmode_send_done( struct mgsl_struct * info );
848
849 /* set non-zero on successful registration with PCI subsystem */
850 static int pci_registered;
851
852 /*
853  * Global linked list of SyncLink devices
854  */
855 static struct mgsl_struct *mgsl_device_list;
856 static int mgsl_device_count;
857
858 /*
859  * Set this param to non-zero to load eax with the
860  * .text section address and breakpoint on module load.
861  * This is useful for use with gdb and add-symbol-file command.
862  */
863 static int break_on_load;
864
865 /*
866  * Driver major number, defaults to zero to get auto
867  * assigned major number. May be forced as module parameter.
868  */
869 static int ttymajor;
870
871 /*
872  * Array of user specified options for ISA adapters.
873  */
874 static int io[MAX_ISA_DEVICES];
875 static int irq[MAX_ISA_DEVICES];
876 static int dma[MAX_ISA_DEVICES];
877 static int debug_level;
878 static int maxframe[MAX_TOTAL_DEVICES];
879 static int dosyncppp[MAX_TOTAL_DEVICES];
880 static int txdmabufs[MAX_TOTAL_DEVICES];
881 static int txholdbufs[MAX_TOTAL_DEVICES];
882         
883 module_param(break_on_load, bool, 0);
884 module_param(ttymajor, int, 0);
885 module_param_array(io, int, NULL, 0);
886 module_param_array(irq, int, NULL, 0);
887 module_param_array(dma, int, NULL, 0);
888 module_param(debug_level, int, 0);
889 module_param_array(maxframe, int, NULL, 0);
890 module_param_array(dosyncppp, int, NULL, 0);
891 module_param_array(txdmabufs, int, NULL, 0);
892 module_param_array(txholdbufs, int, NULL, 0);
893
894 static char *driver_name = "SyncLink serial driver";
895 static char *driver_version = "$Revision: 4.38 $";
896
897 static int synclink_init_one (struct pci_dev *dev,
898                                      const struct pci_device_id *ent);
899 static void synclink_remove_one (struct pci_dev *dev);
900
901 static struct pci_device_id synclink_pci_tbl[] = {
902         { PCI_VENDOR_ID_MICROGATE, PCI_DEVICE_ID_MICROGATE_USC, PCI_ANY_ID, PCI_ANY_ID, },
903         { PCI_VENDOR_ID_MICROGATE, 0x0210, PCI_ANY_ID, PCI_ANY_ID, },
904         { 0, }, /* terminate list */
905 };
906 MODULE_DEVICE_TABLE(pci, synclink_pci_tbl);
907
908 MODULE_LICENSE("GPL");
909
910 static struct pci_driver synclink_pci_driver = {
911         .name           = "synclink",
912         .id_table       = synclink_pci_tbl,
913         .probe          = synclink_init_one,
914         .remove         = __devexit_p(synclink_remove_one),
915 };
916
917 static struct tty_driver *serial_driver;
918
919 /* number of characters left in xmit buffer before we ask for more */
920 #define WAKEUP_CHARS 256
921
922
923 static void mgsl_change_params(struct mgsl_struct *info);
924 static void mgsl_wait_until_sent(struct tty_struct *tty, int timeout);
925
926 /*
927  * 1st function defined in .text section. Calling this function in
928  * init_module() followed by a breakpoint allows a remote debugger
929  * (gdb) to get the .text address for the add-symbol-file command.
930  * This allows remote debugging of dynamically loadable modules.
931  */
932 static void* mgsl_get_text_ptr(void)
933 {
934         return mgsl_get_text_ptr;
935 }
936
937 static inline int mgsl_paranoia_check(struct mgsl_struct *info,
938                                         char *name, const char *routine)
939 {
940 #ifdef MGSL_PARANOIA_CHECK
941         static const char *badmagic =
942                 "Warning: bad magic number for mgsl struct (%s) in %s\n";
943         static const char *badinfo =
944                 "Warning: null mgsl_struct for (%s) in %s\n";
945
946         if (!info) {
947                 printk(badinfo, name, routine);
948                 return 1;
949         }
950         if (info->magic != MGSL_MAGIC) {
951                 printk(badmagic, name, routine);
952                 return 1;
953         }
954 #else
955         if (!info)
956                 return 1;
957 #endif
958         return 0;
959 }
960
961 /**
962  * line discipline callback wrappers
963  *
964  * The wrappers maintain line discipline references
965  * while calling into the line discipline.
966  *
967  * ldisc_receive_buf  - pass receive data to line discipline
968  */
969
970 static void ldisc_receive_buf(struct tty_struct *tty,
971                               const __u8 *data, char *flags, int count)
972 {
973         struct tty_ldisc *ld;
974         if (!tty)
975                 return;
976         ld = tty_ldisc_ref(tty);
977         if (ld) {
978                 if (ld->receive_buf)
979                         ld->receive_buf(tty, data, flags, count);
980                 tty_ldisc_deref(ld);
981         }
982 }
983
984 /* mgsl_stop()          throttle (stop) transmitter
985  *      
986  * Arguments:           tty     pointer to tty info structure
987  * Return Value:        None
988  */
989 static void mgsl_stop(struct tty_struct *tty)
990 {
991         struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
992         unsigned long flags;
993         
994         if (mgsl_paranoia_check(info, tty->name, "mgsl_stop"))
995                 return;
996         
997         if ( debug_level >= DEBUG_LEVEL_INFO )
998                 printk("mgsl_stop(%s)\n",info->device_name);    
999                 
1000         spin_lock_irqsave(&info->irq_spinlock,flags);
1001         if (info->tx_enabled)
1002                 usc_stop_transmitter(info);
1003         spin_unlock_irqrestore(&info->irq_spinlock,flags);
1004         
1005 }       /* end of mgsl_stop() */
1006
1007 /* mgsl_start()         release (start) transmitter
1008  *      
1009  * Arguments:           tty     pointer to tty info structure
1010  * Return Value:        None
1011  */
1012 static void mgsl_start(struct tty_struct *tty)
1013 {
1014         struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
1015         unsigned long flags;
1016         
1017         if (mgsl_paranoia_check(info, tty->name, "mgsl_start"))
1018                 return;
1019         
1020         if ( debug_level >= DEBUG_LEVEL_INFO )
1021                 printk("mgsl_start(%s)\n",info->device_name);   
1022                 
1023         spin_lock_irqsave(&info->irq_spinlock,flags);
1024         if (!info->tx_enabled)
1025                 usc_start_transmitter(info);
1026         spin_unlock_irqrestore(&info->irq_spinlock,flags);
1027         
1028 }       /* end of mgsl_start() */
1029
1030 /*
1031  * Bottom half work queue access functions
1032  */
1033
1034 /* mgsl_bh_action()     Return next bottom half action to perform.
1035  * Return Value:        BH action code or 0 if nothing to do.
1036  */
1037 static int mgsl_bh_action(struct mgsl_struct *info)
1038 {
1039         unsigned long flags;
1040         int rc = 0;
1041         
1042         spin_lock_irqsave(&info->irq_spinlock,flags);
1043
1044         if (info->pending_bh & BH_RECEIVE) {
1045                 info->pending_bh &= ~BH_RECEIVE;
1046                 rc = BH_RECEIVE;
1047         } else if (info->pending_bh & BH_TRANSMIT) {
1048                 info->pending_bh &= ~BH_TRANSMIT;
1049                 rc = BH_TRANSMIT;
1050         } else if (info->pending_bh & BH_STATUS) {
1051                 info->pending_bh &= ~BH_STATUS;
1052                 rc = BH_STATUS;
1053         }
1054
1055         if (!rc) {
1056                 /* Mark BH routine as complete */
1057                 info->bh_running   = 0;
1058                 info->bh_requested = 0;
1059         }
1060         
1061         spin_unlock_irqrestore(&info->irq_spinlock,flags);
1062         
1063         return rc;
1064 }
1065
1066 /*
1067  *      Perform bottom half processing of work items queued by ISR.
1068  */
1069 static void mgsl_bh_handler(struct work_struct *work)
1070 {
1071         struct mgsl_struct *info =
1072                 container_of(work, struct mgsl_struct, task);
1073         int action;
1074
1075         if (!info)
1076                 return;
1077                 
1078         if ( debug_level >= DEBUG_LEVEL_BH )
1079                 printk( "%s(%d):mgsl_bh_handler(%s) entry\n",
1080                         __FILE__,__LINE__,info->device_name);
1081         
1082         info->bh_running = 1;
1083
1084         while((action = mgsl_bh_action(info)) != 0) {
1085         
1086                 /* Process work item */
1087                 if ( debug_level >= DEBUG_LEVEL_BH )
1088                         printk( "%s(%d):mgsl_bh_handler() work item action=%d\n",
1089                                 __FILE__,__LINE__,action);
1090
1091                 switch (action) {
1092                 
1093                 case BH_RECEIVE:
1094                         mgsl_bh_receive(info);
1095                         break;
1096                 case BH_TRANSMIT:
1097                         mgsl_bh_transmit(info);
1098                         break;
1099                 case BH_STATUS:
1100                         mgsl_bh_status(info);
1101                         break;
1102                 default:
1103                         /* unknown work item ID */
1104                         printk("Unknown work item ID=%08X!\n", action);
1105                         break;
1106                 }
1107         }
1108
1109         if ( debug_level >= DEBUG_LEVEL_BH )
1110                 printk( "%s(%d):mgsl_bh_handler(%s) exit\n",
1111                         __FILE__,__LINE__,info->device_name);
1112 }
1113
1114 static void mgsl_bh_receive(struct mgsl_struct *info)
1115 {
1116         int (*get_rx_frame)(struct mgsl_struct *info) =
1117                 (info->params.mode == MGSL_MODE_HDLC ? mgsl_get_rx_frame : mgsl_get_raw_rx_frame);
1118
1119         if ( debug_level >= DEBUG_LEVEL_BH )
1120                 printk( "%s(%d):mgsl_bh_receive(%s)\n",
1121                         __FILE__,__LINE__,info->device_name);
1122         
1123         do
1124         {
1125                 if (info->rx_rcc_underrun) {
1126                         unsigned long flags;
1127                         spin_lock_irqsave(&info->irq_spinlock,flags);
1128                         usc_start_receiver(info);
1129                         spin_unlock_irqrestore(&info->irq_spinlock,flags);
1130                         return;
1131                 }
1132         } while(get_rx_frame(info));
1133 }
1134
1135 static void mgsl_bh_transmit(struct mgsl_struct *info)
1136 {
1137         struct tty_struct *tty = info->tty;
1138         unsigned long flags;
1139         
1140         if ( debug_level >= DEBUG_LEVEL_BH )
1141                 printk( "%s(%d):mgsl_bh_transmit() entry on %s\n",
1142                         __FILE__,__LINE__,info->device_name);
1143
1144         if (tty)
1145                 tty_wakeup(tty);
1146
1147         /* if transmitter idle and loopmode_send_done_requested
1148          * then start echoing RxD to TxD
1149          */
1150         spin_lock_irqsave(&info->irq_spinlock,flags);
1151         if ( !info->tx_active && info->loopmode_send_done_requested )
1152                 usc_loopmode_send_done( info );
1153         spin_unlock_irqrestore(&info->irq_spinlock,flags);
1154 }
1155
1156 static void mgsl_bh_status(struct mgsl_struct *info)
1157 {
1158         if ( debug_level >= DEBUG_LEVEL_BH )
1159                 printk( "%s(%d):mgsl_bh_status() entry on %s\n",
1160                         __FILE__,__LINE__,info->device_name);
1161
1162         info->ri_chkcount = 0;
1163         info->dsr_chkcount = 0;
1164         info->dcd_chkcount = 0;
1165         info->cts_chkcount = 0;
1166 }
1167
1168 /* mgsl_isr_receive_status()
1169  * 
1170  *      Service a receive status interrupt. The type of status
1171  *      interrupt is indicated by the state of the RCSR.
1172  *      This is only used for HDLC mode.
1173  *
1174  * Arguments:           info    pointer to device instance data
1175  * Return Value:        None
1176  */
1177 static void mgsl_isr_receive_status( struct mgsl_struct *info )
1178 {
1179         u16 status = usc_InReg( info, RCSR );
1180
1181         if ( debug_level >= DEBUG_LEVEL_ISR )   
1182                 printk("%s(%d):mgsl_isr_receive_status status=%04X\n",
1183                         __FILE__,__LINE__,status);
1184                         
1185         if ( (status & RXSTATUS_ABORT_RECEIVED) && 
1186                 info->loopmode_insert_requested &&
1187                 usc_loopmode_active(info) )
1188         {
1189                 ++info->icount.rxabort;
1190                 info->loopmode_insert_requested = FALSE;
1191  
1192                 /* clear CMR:13 to start echoing RxD to TxD */
1193                 info->cmr_value &= ~BIT13;
1194                 usc_OutReg(info, CMR, info->cmr_value);
1195  
1196                 /* disable received abort irq (no longer required) */
1197                 usc_OutReg(info, RICR,
1198                         (usc_InReg(info, RICR) & ~RXSTATUS_ABORT_RECEIVED));
1199         }
1200
1201         if (status & (RXSTATUS_EXITED_HUNT + RXSTATUS_IDLE_RECEIVED)) {
1202                 if (status & RXSTATUS_EXITED_HUNT)
1203                         info->icount.exithunt++;
1204                 if (status & RXSTATUS_IDLE_RECEIVED)
1205                         info->icount.rxidle++;
1206                 wake_up_interruptible(&info->event_wait_q);
1207         }
1208
1209         if (status & RXSTATUS_OVERRUN){
1210                 info->icount.rxover++;
1211                 usc_process_rxoverrun_sync( info );
1212         }
1213
1214         usc_ClearIrqPendingBits( info, RECEIVE_STATUS );
1215         usc_UnlatchRxstatusBits( info, status );
1216
1217 }       /* end of mgsl_isr_receive_status() */
1218
1219 /* mgsl_isr_transmit_status()
1220  * 
1221  *      Service a transmit status interrupt
1222  *      HDLC mode :end of transmit frame
1223  *      Async mode:all data is sent
1224  *      transmit status is indicated by bits in the TCSR.
1225  * 
1226  * Arguments:           info           pointer to device instance data
1227  * Return Value:        None
1228  */
1229 static void mgsl_isr_transmit_status( struct mgsl_struct *info )
1230 {
1231         u16 status = usc_InReg( info, TCSR );
1232
1233         if ( debug_level >= DEBUG_LEVEL_ISR )   
1234                 printk("%s(%d):mgsl_isr_transmit_status status=%04X\n",
1235                         __FILE__,__LINE__,status);
1236         
1237         usc_ClearIrqPendingBits( info, TRANSMIT_STATUS );
1238         usc_UnlatchTxstatusBits( info, status );
1239         
1240         if ( status & (TXSTATUS_UNDERRUN | TXSTATUS_ABORT_SENT) )
1241         {
1242                 /* finished sending HDLC abort. This may leave  */
1243                 /* the TxFifo with data from the aborted frame  */
1244                 /* so purge the TxFifo. Also shutdown the DMA   */
1245                 /* channel in case there is data remaining in   */
1246                 /* the DMA buffer                               */
1247                 usc_DmaCmd( info, DmaCmd_ResetTxChannel );
1248                 usc_RTCmd( info, RTCmd_PurgeTxFifo );
1249         }
1250  
1251         if ( status & TXSTATUS_EOF_SENT )
1252                 info->icount.txok++;
1253         else if ( status & TXSTATUS_UNDERRUN )
1254                 info->icount.txunder++;
1255         else if ( status & TXSTATUS_ABORT_SENT )
1256                 info->icount.txabort++;
1257         else
1258                 info->icount.txunder++;
1259                         
1260         info->tx_active = 0;
1261         info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
1262         del_timer(&info->tx_timer);     
1263         
1264         if ( info->drop_rts_on_tx_done ) {
1265                 usc_get_serial_signals( info );
1266                 if ( info->serial_signals & SerialSignal_RTS ) {
1267                         info->serial_signals &= ~SerialSignal_RTS;
1268                         usc_set_serial_signals( info );
1269                 }
1270                 info->drop_rts_on_tx_done = 0;
1271         }
1272
1273 #if SYNCLINK_GENERIC_HDLC
1274         if (info->netcount)
1275                 hdlcdev_tx_done(info);
1276         else 
1277 #endif
1278         {
1279                 if (info->tty->stopped || info->tty->hw_stopped) {
1280                         usc_stop_transmitter(info);
1281                         return;
1282                 }
1283                 info->pending_bh |= BH_TRANSMIT;
1284         }
1285
1286 }       /* end of mgsl_isr_transmit_status() */
1287
1288 /* mgsl_isr_io_pin()
1289  * 
1290  *      Service an Input/Output pin interrupt. The type of
1291  *      interrupt is indicated by bits in the MISR
1292  *      
1293  * Arguments:           info           pointer to device instance data
1294  * Return Value:        None
1295  */
1296 static void mgsl_isr_io_pin( struct mgsl_struct *info )
1297 {
1298         struct  mgsl_icount *icount;
1299         u16 status = usc_InReg( info, MISR );
1300
1301         if ( debug_level >= DEBUG_LEVEL_ISR )   
1302                 printk("%s(%d):mgsl_isr_io_pin status=%04X\n",
1303                         __FILE__,__LINE__,status);
1304                         
1305         usc_ClearIrqPendingBits( info, IO_PIN );
1306         usc_UnlatchIostatusBits( info, status );
1307
1308         if (status & (MISCSTATUS_CTS_LATCHED | MISCSTATUS_DCD_LATCHED |
1309                       MISCSTATUS_DSR_LATCHED | MISCSTATUS_RI_LATCHED) ) {
1310                 icount = &info->icount;
1311                 /* update input line counters */
1312                 if (status & MISCSTATUS_RI_LATCHED) {
1313                         if ((info->ri_chkcount)++ >= IO_PIN_SHUTDOWN_LIMIT)
1314                                 usc_DisablestatusIrqs(info,SICR_RI);
1315                         icount->rng++;
1316                         if ( status & MISCSTATUS_RI )
1317                                 info->input_signal_events.ri_up++;      
1318                         else
1319                                 info->input_signal_events.ri_down++;    
1320                 }
1321                 if (status & MISCSTATUS_DSR_LATCHED) {
1322                         if ((info->dsr_chkcount)++ >= IO_PIN_SHUTDOWN_LIMIT)
1323                                 usc_DisablestatusIrqs(info,SICR_DSR);
1324                         icount->dsr++;
1325                         if ( status & MISCSTATUS_DSR )
1326                                 info->input_signal_events.dsr_up++;
1327                         else
1328                                 info->input_signal_events.dsr_down++;
1329                 }
1330                 if (status & MISCSTATUS_DCD_LATCHED) {
1331                         if ((info->dcd_chkcount)++ >= IO_PIN_SHUTDOWN_LIMIT)
1332                                 usc_DisablestatusIrqs(info,SICR_DCD);
1333                         icount->dcd++;
1334                         if (status & MISCSTATUS_DCD) {
1335                                 info->input_signal_events.dcd_up++;
1336                         } else
1337                                 info->input_signal_events.dcd_down++;
1338 #if SYNCLINK_GENERIC_HDLC
1339                         if (info->netcount) {
1340                                 if (status & MISCSTATUS_DCD)
1341                                         netif_carrier_on(info->netdev);
1342                                 else
1343                                         netif_carrier_off(info->netdev);
1344                         }
1345 #endif
1346                 }
1347                 if (status & MISCSTATUS_CTS_LATCHED)
1348                 {
1349                         if ((info->cts_chkcount)++ >= IO_PIN_SHUTDOWN_LIMIT)
1350                                 usc_DisablestatusIrqs(info,SICR_CTS);
1351                         icount->cts++;
1352                         if ( status & MISCSTATUS_CTS )
1353                                 info->input_signal_events.cts_up++;
1354                         else
1355                                 info->input_signal_events.cts_down++;
1356                 }
1357                 wake_up_interruptible(&info->status_event_wait_q);
1358                 wake_up_interruptible(&info->event_wait_q);
1359
1360                 if ( (info->flags & ASYNC_CHECK_CD) && 
1361                      (status & MISCSTATUS_DCD_LATCHED) ) {
1362                         if ( debug_level >= DEBUG_LEVEL_ISR )
1363                                 printk("%s CD now %s...", info->device_name,
1364                                        (status & MISCSTATUS_DCD) ? "on" : "off");
1365                         if (status & MISCSTATUS_DCD)
1366                                 wake_up_interruptible(&info->open_wait);
1367                         else {
1368                                 if ( debug_level >= DEBUG_LEVEL_ISR )
1369                                         printk("doing serial hangup...");
1370                                 if (info->tty)
1371                                         tty_hangup(info->tty);
1372                         }
1373                 }
1374         
1375                 if ( (info->flags & ASYNC_CTS_FLOW) && 
1376                      (status & MISCSTATUS_CTS_LATCHED) ) {
1377                         if (info->tty->hw_stopped) {
1378                                 if (status & MISCSTATUS_CTS) {
1379                                         if ( debug_level >= DEBUG_LEVEL_ISR )
1380                                                 printk("CTS tx start...");
1381                                         if (info->tty)
1382                                                 info->tty->hw_stopped = 0;
1383                                         usc_start_transmitter(info);
1384                                         info->pending_bh |= BH_TRANSMIT;
1385                                         return;
1386                                 }
1387                         } else {
1388                                 if (!(status & MISCSTATUS_CTS)) {
1389                                         if ( debug_level >= DEBUG_LEVEL_ISR )
1390                                                 printk("CTS tx stop...");
1391                                         if (info->tty)
1392                                                 info->tty->hw_stopped = 1;
1393                                         usc_stop_transmitter(info);
1394                                 }
1395                         }
1396                 }
1397         }
1398
1399         info->pending_bh |= BH_STATUS;
1400         
1401         /* for diagnostics set IRQ flag */
1402         if ( status & MISCSTATUS_TXC_LATCHED ){
1403                 usc_OutReg( info, SICR,
1404                         (unsigned short)(usc_InReg(info,SICR) & ~(SICR_TXC_ACTIVE+SICR_TXC_INACTIVE)) );
1405                 usc_UnlatchIostatusBits( info, MISCSTATUS_TXC_LATCHED );
1406                 info->irq_occurred = 1;
1407         }
1408
1409 }       /* end of mgsl_isr_io_pin() */
1410
1411 /* mgsl_isr_transmit_data()
1412  * 
1413  *      Service a transmit data interrupt (async mode only).
1414  * 
1415  * Arguments:           info    pointer to device instance data
1416  * Return Value:        None
1417  */
1418 static void mgsl_isr_transmit_data( struct mgsl_struct *info )
1419 {
1420         if ( debug_level >= DEBUG_LEVEL_ISR )   
1421                 printk("%s(%d):mgsl_isr_transmit_data xmit_cnt=%d\n",
1422                         __FILE__,__LINE__,info->xmit_cnt);
1423                         
1424         usc_ClearIrqPendingBits( info, TRANSMIT_DATA );
1425         
1426         if (info->tty->stopped || info->tty->hw_stopped) {
1427                 usc_stop_transmitter(info);
1428                 return;
1429         }
1430         
1431         if ( info->xmit_cnt )
1432                 usc_load_txfifo( info );
1433         else
1434                 info->tx_active = 0;
1435                 
1436         if (info->xmit_cnt < WAKEUP_CHARS)
1437                 info->pending_bh |= BH_TRANSMIT;
1438
1439 }       /* end of mgsl_isr_transmit_data() */
1440
1441 /* mgsl_isr_receive_data()
1442  * 
1443  *      Service a receive data interrupt. This occurs
1444  *      when operating in asynchronous interrupt transfer mode.
1445  *      The receive data FIFO is flushed to the receive data buffers. 
1446  * 
1447  * Arguments:           info            pointer to device instance data
1448  * Return Value:        None
1449  */
1450 static void mgsl_isr_receive_data( struct mgsl_struct *info )
1451 {
1452         int Fifocount;
1453         u16 status;
1454         int work = 0;
1455         unsigned char DataByte;
1456         struct tty_struct *tty = info->tty;
1457         struct  mgsl_icount *icount = &info->icount;
1458         
1459         if ( debug_level >= DEBUG_LEVEL_ISR )   
1460                 printk("%s(%d):mgsl_isr_receive_data\n",
1461                         __FILE__,__LINE__);
1462
1463         usc_ClearIrqPendingBits( info, RECEIVE_DATA );
1464         
1465         /* select FIFO status for RICR readback */
1466         usc_RCmd( info, RCmd_SelectRicrRxFifostatus );
1467
1468         /* clear the Wordstatus bit so that status readback */
1469         /* only reflects the status of this byte */
1470         usc_OutReg( info, RICR+LSBONLY, (u16)(usc_InReg(info, RICR+LSBONLY) & ~BIT3 ));
1471
1472         /* flush the receive FIFO */
1473
1474         while( (Fifocount = (usc_InReg(info,RICR) >> 8)) ) {
1475                 int flag;
1476
1477                 /* read one byte from RxFIFO */
1478                 outw( (inw(info->io_base + CCAR) & 0x0780) | (RDR+LSBONLY),
1479                       info->io_base + CCAR );
1480                 DataByte = inb( info->io_base + CCAR );
1481
1482                 /* get the status of the received byte */
1483                 status = usc_InReg(info, RCSR);
1484                 if ( status & (RXSTATUS_FRAMING_ERROR + RXSTATUS_PARITY_ERROR +
1485                                 RXSTATUS_OVERRUN + RXSTATUS_BREAK_RECEIVED) )
1486                         usc_UnlatchRxstatusBits(info,RXSTATUS_ALL);
1487                 
1488                 icount->rx++;
1489                 
1490                 flag = 0;
1491                 if ( status & (RXSTATUS_FRAMING_ERROR + RXSTATUS_PARITY_ERROR +
1492                                 RXSTATUS_OVERRUN + RXSTATUS_BREAK_RECEIVED) ) {
1493                         printk("rxerr=%04X\n",status);                                  
1494                         /* update error statistics */
1495                         if ( status & RXSTATUS_BREAK_RECEIVED ) {
1496                                 status &= ~(RXSTATUS_FRAMING_ERROR + RXSTATUS_PARITY_ERROR);
1497                                 icount->brk++;
1498                         } else if (status & RXSTATUS_PARITY_ERROR) 
1499                                 icount->parity++;
1500                         else if (status & RXSTATUS_FRAMING_ERROR)
1501                                 icount->frame++;
1502                         else if (status & RXSTATUS_OVERRUN) {
1503                                 /* must issue purge fifo cmd before */
1504                                 /* 16C32 accepts more receive chars */
1505                                 usc_RTCmd(info,RTCmd_PurgeRxFifo);
1506                                 icount->overrun++;
1507                         }
1508
1509                         /* discard char if tty control flags say so */                                  
1510                         if (status & info->ignore_status_mask)
1511                                 continue;
1512                                 
1513                         status &= info->read_status_mask;
1514                 
1515                         if (status & RXSTATUS_BREAK_RECEIVED) {
1516                                 flag = TTY_BREAK;
1517                                 if (info->flags & ASYNC_SAK)
1518                                         do_SAK(tty);
1519                         } else if (status & RXSTATUS_PARITY_ERROR)
1520                                 flag = TTY_PARITY;
1521                         else if (status & RXSTATUS_FRAMING_ERROR)
1522                                 flag = TTY_FRAME;
1523                 }       /* end of if (error) */
1524                 tty_insert_flip_char(tty, DataByte, flag);
1525                 if (status & RXSTATUS_OVERRUN) {
1526                         /* Overrun is special, since it's
1527                          * reported immediately, and doesn't
1528                          * affect the current character
1529                          */
1530                         work += tty_insert_flip_char(tty, 0, TTY_OVERRUN);
1531                 }
1532         }
1533
1534         if ( debug_level >= DEBUG_LEVEL_ISR ) {
1535                 printk("%s(%d):rx=%d brk=%d parity=%d frame=%d overrun=%d\n",
1536                         __FILE__,__LINE__,icount->rx,icount->brk,
1537                         icount->parity,icount->frame,icount->overrun);
1538         }
1539                         
1540         if(work)
1541                 tty_flip_buffer_push(tty);
1542 }
1543
1544 /* mgsl_isr_misc()
1545  * 
1546  *      Service a miscellaneous interrupt source.
1547  *      
1548  * Arguments:           info            pointer to device extension (instance data)
1549  * Return Value:        None
1550  */
1551 static void mgsl_isr_misc( struct mgsl_struct *info )
1552 {
1553         u16 status = usc_InReg( info, MISR );
1554
1555         if ( debug_level >= DEBUG_LEVEL_ISR )   
1556                 printk("%s(%d):mgsl_isr_misc status=%04X\n",
1557                         __FILE__,__LINE__,status);
1558                         
1559         if ((status & MISCSTATUS_RCC_UNDERRUN) &&
1560             (info->params.mode == MGSL_MODE_HDLC)) {
1561
1562                 /* turn off receiver and rx DMA */
1563                 usc_EnableReceiver(info,DISABLE_UNCONDITIONAL);
1564                 usc_DmaCmd(info, DmaCmd_ResetRxChannel);
1565                 usc_UnlatchRxstatusBits(info, RXSTATUS_ALL);
1566                 usc_ClearIrqPendingBits(info, RECEIVE_DATA + RECEIVE_STATUS);
1567                 usc_DisableInterrupts(info, RECEIVE_DATA + RECEIVE_STATUS);
1568
1569                 /* schedule BH handler to restart receiver */
1570                 info->pending_bh |= BH_RECEIVE;
1571                 info->rx_rcc_underrun = 1;
1572         }
1573
1574         usc_ClearIrqPendingBits( info, MISC );
1575         usc_UnlatchMiscstatusBits( info, status );
1576
1577 }       /* end of mgsl_isr_misc() */
1578
1579 /* mgsl_isr_null()
1580  *
1581  *      Services undefined interrupt vectors from the
1582  *      USC. (hence this function SHOULD never be called)
1583  * 
1584  * Arguments:           info            pointer to device extension (instance data)
1585  * Return Value:        None
1586  */
1587 static void mgsl_isr_null( struct mgsl_struct *info )
1588 {
1589
1590 }       /* end of mgsl_isr_null() */
1591
1592 /* mgsl_isr_receive_dma()
1593  * 
1594  *      Service a receive DMA channel interrupt.
1595  *      For this driver there are two sources of receive DMA interrupts
1596  *      as identified in the Receive DMA mode Register (RDMR):
1597  * 
1598  *      BIT3    EOA/EOL         End of List, all receive buffers in receive
1599  *                              buffer list have been filled (no more free buffers
1600  *                              available). The DMA controller has shut down.
1601  * 
1602  *      BIT2    EOB             End of Buffer. This interrupt occurs when a receive
1603  *                              DMA buffer is terminated in response to completion
1604  *                              of a good frame or a frame with errors. The status
1605  *                              of the frame is stored in the buffer entry in the
1606  *                              list of receive buffer entries.
1607  * 
1608  * Arguments:           info            pointer to device instance data
1609  * Return Value:        None
1610  */
1611 static void mgsl_isr_receive_dma( struct mgsl_struct *info )
1612 {
1613         u16 status;
1614         
1615         /* clear interrupt pending and IUS bit for Rx DMA IRQ */
1616         usc_OutDmaReg( info, CDIR, BIT9+BIT1 );
1617
1618         /* Read the receive DMA status to identify interrupt type. */
1619         /* This also clears the status bits. */
1620         status = usc_InDmaReg( info, RDMR );
1621
1622         if ( debug_level >= DEBUG_LEVEL_ISR )   
1623                 printk("%s(%d):mgsl_isr_receive_dma(%s) status=%04X\n",
1624                         __FILE__,__LINE__,info->device_name,status);
1625                         
1626         info->pending_bh |= BH_RECEIVE;
1627         
1628         if ( status & BIT3 ) {
1629                 info->rx_overflow = 1;
1630                 info->icount.buf_overrun++;
1631         }
1632
1633 }       /* end of mgsl_isr_receive_dma() */
1634
1635 /* mgsl_isr_transmit_dma()
1636  *
1637  *      This function services a transmit DMA channel interrupt.
1638  *
1639  *      For this driver there is one source of transmit DMA interrupts
1640  *      as identified in the Transmit DMA Mode Register (TDMR):
1641  *
1642  *      BIT2  EOB       End of Buffer. This interrupt occurs when a
1643  *                      transmit DMA buffer has been emptied.
1644  *
1645  *      The driver maintains enough transmit DMA buffers to hold at least
1646  *      one max frame size transmit frame. When operating in a buffered
1647  *      transmit mode, there may be enough transmit DMA buffers to hold at
1648  *      least two or more max frame size frames. On an EOB condition,
1649  *      determine if there are any queued transmit buffers and copy into
1650  *      transmit DMA buffers if we have room.
1651  *
1652  * Arguments:           info            pointer to device instance data
1653  * Return Value:        None
1654  */
1655 static void mgsl_isr_transmit_dma( struct mgsl_struct *info )
1656 {
1657         u16 status;
1658
1659         /* clear interrupt pending and IUS bit for Tx DMA IRQ */
1660         usc_OutDmaReg(info, CDIR, BIT8+BIT0 );
1661
1662         /* Read the transmit DMA status to identify interrupt type. */
1663         /* This also clears the status bits. */
1664
1665         status = usc_InDmaReg( info, TDMR );
1666
1667         if ( debug_level >= DEBUG_LEVEL_ISR )
1668                 printk("%s(%d):mgsl_isr_transmit_dma(%s) status=%04X\n",
1669                         __FILE__,__LINE__,info->device_name,status);
1670
1671         if ( status & BIT2 ) {
1672                 --info->tx_dma_buffers_used;
1673
1674                 /* if there are transmit frames queued,
1675                  *  try to load the next one
1676                  */
1677                 if ( load_next_tx_holding_buffer(info) ) {
1678                         /* if call returns non-zero value, we have
1679                          * at least one free tx holding buffer
1680                          */
1681                         info->pending_bh |= BH_TRANSMIT;
1682                 }
1683         }
1684
1685 }       /* end of mgsl_isr_transmit_dma() */
1686
1687 /* mgsl_interrupt()
1688  * 
1689  *      Interrupt service routine entry point.
1690  *      
1691  * Arguments:
1692  * 
1693  *      irq             interrupt number that caused interrupt
1694  *      dev_id          device ID supplied during interrupt registration
1695  *      
1696  * Return Value: None
1697  */
1698 static irqreturn_t mgsl_interrupt(int dummy, void *dev_id)
1699 {
1700         struct mgsl_struct *info = dev_id;
1701         u16 UscVector;
1702         u16 DmaVector;
1703
1704         if ( debug_level >= DEBUG_LEVEL_ISR )   
1705                 printk(KERN_DEBUG "%s(%d):mgsl_interrupt(%d)entry.\n",
1706                         __FILE__, __LINE__, info->irq_level);
1707
1708         spin_lock(&info->irq_spinlock);
1709
1710         for(;;) {
1711                 /* Read the interrupt vectors from hardware. */
1712                 UscVector = usc_InReg(info, IVR) >> 9;
1713                 DmaVector = usc_InDmaReg(info, DIVR);
1714                 
1715                 if ( debug_level >= DEBUG_LEVEL_ISR )   
1716                         printk("%s(%d):%s UscVector=%08X DmaVector=%08X\n",
1717                                 __FILE__,__LINE__,info->device_name,UscVector,DmaVector);
1718                         
1719                 if ( !UscVector && !DmaVector )
1720                         break;
1721                         
1722                 /* Dispatch interrupt vector */
1723                 if ( UscVector )
1724                         (*UscIsrTable[UscVector])(info);
1725                 else if ( (DmaVector&(BIT10|BIT9)) == BIT10)
1726                         mgsl_isr_transmit_dma(info);
1727                 else
1728                         mgsl_isr_receive_dma(info);
1729
1730                 if ( info->isr_overflow ) {
1731                         printk(KERN_ERR "%s(%d):%s isr overflow irq=%d\n",
1732                                 __FILE__, __LINE__, info->device_name, info->irq_level);
1733                         usc_DisableMasterIrqBit(info);
1734                         usc_DisableDmaInterrupts(info,DICR_MASTER);
1735                         break;
1736                 }
1737         }
1738         
1739         /* Request bottom half processing if there's something 
1740          * for it to do and the bh is not already running
1741          */
1742
1743         if ( info->pending_bh && !info->bh_running && !info->bh_requested ) {
1744                 if ( debug_level >= DEBUG_LEVEL_ISR )   
1745                         printk("%s(%d):%s queueing bh task.\n",
1746                                 __FILE__,__LINE__,info->device_name);
1747                 schedule_work(&info->task);
1748                 info->bh_requested = 1;
1749         }
1750
1751         spin_unlock(&info->irq_spinlock);
1752         
1753         if ( debug_level >= DEBUG_LEVEL_ISR )   
1754                 printk(KERN_DEBUG "%s(%d):mgsl_interrupt(%d)exit.\n",
1755                         __FILE__, __LINE__, info->irq_level);
1756
1757         return IRQ_HANDLED;
1758 }       /* end of mgsl_interrupt() */
1759
1760 /* startup()
1761  * 
1762  *      Initialize and start device.
1763  *      
1764  * Arguments:           info    pointer to device instance data
1765  * Return Value:        0 if success, otherwise error code
1766  */
1767 static int startup(struct mgsl_struct * info)
1768 {
1769         int retval = 0;
1770         
1771         if ( debug_level >= DEBUG_LEVEL_INFO )
1772                 printk("%s(%d):mgsl_startup(%s)\n",__FILE__,__LINE__,info->device_name);
1773                 
1774         if (info->flags & ASYNC_INITIALIZED)
1775                 return 0;
1776         
1777         if (!info->xmit_buf) {
1778                 /* allocate a page of memory for a transmit buffer */
1779                 info->xmit_buf = (unsigned char *)get_zeroed_page(GFP_KERNEL);
1780                 if (!info->xmit_buf) {
1781                         printk(KERN_ERR"%s(%d):%s can't allocate transmit buffer\n",
1782                                 __FILE__,__LINE__,info->device_name);
1783                         return -ENOMEM;
1784                 }
1785         }
1786
1787         info->pending_bh = 0;
1788         
1789         memset(&info->icount, 0, sizeof(info->icount));
1790
1791         setup_timer(&info->tx_timer, mgsl_tx_timeout, (unsigned long)info);
1792         
1793         /* Allocate and claim adapter resources */
1794         retval = mgsl_claim_resources(info);
1795         
1796         /* perform existence check and diagnostics */
1797         if ( !retval )
1798                 retval = mgsl_adapter_test(info);
1799                 
1800         if ( retval ) {
1801                 if (capable(CAP_SYS_ADMIN) && info->tty)
1802                         set_bit(TTY_IO_ERROR, &info->tty->flags);
1803                 mgsl_release_resources(info);
1804                 return retval;
1805         }
1806
1807         /* program hardware for current parameters */
1808         mgsl_change_params(info);
1809         
1810         if (info->tty)
1811                 clear_bit(TTY_IO_ERROR, &info->tty->flags);
1812
1813         info->flags |= ASYNC_INITIALIZED;
1814         
1815         return 0;
1816         
1817 }       /* end of startup() */
1818
1819 /* shutdown()
1820  *
1821  * Called by mgsl_close() and mgsl_hangup() to shutdown hardware
1822  *
1823  * Arguments:           info    pointer to device instance data
1824  * Return Value:        None
1825  */
1826 static void shutdown(struct mgsl_struct * info)
1827 {
1828         unsigned long flags;
1829         
1830         if (!(info->flags & ASYNC_INITIALIZED))
1831                 return;
1832
1833         if (debug_level >= DEBUG_LEVEL_INFO)
1834                 printk("%s(%d):mgsl_shutdown(%s)\n",
1835                          __FILE__,__LINE__, info->device_name );
1836
1837         /* clear status wait queue because status changes */
1838         /* can't happen after shutting down the hardware */
1839         wake_up_interruptible(&info->status_event_wait_q);
1840         wake_up_interruptible(&info->event_wait_q);
1841
1842         del_timer_sync(&info->tx_timer);
1843
1844         if (info->xmit_buf) {
1845                 free_page((unsigned long) info->xmit_buf);
1846                 info->xmit_buf = NULL;
1847         }
1848
1849         spin_lock_irqsave(&info->irq_spinlock,flags);
1850         usc_DisableMasterIrqBit(info);
1851         usc_stop_receiver(info);
1852         usc_stop_transmitter(info);
1853         usc_DisableInterrupts(info,RECEIVE_DATA + RECEIVE_STATUS +
1854                 TRANSMIT_DATA + TRANSMIT_STATUS + IO_PIN + MISC );
1855         usc_DisableDmaInterrupts(info,DICR_MASTER + DICR_TRANSMIT + DICR_RECEIVE);
1856         
1857         /* Disable DMAEN (Port 7, Bit 14) */
1858         /* This disconnects the DMA request signal from the ISA bus */
1859         /* on the ISA adapter. This has no effect for the PCI adapter */
1860         usc_OutReg(info, PCR, (u16)((usc_InReg(info, PCR) | BIT15) | BIT14));
1861         
1862         /* Disable INTEN (Port 6, Bit12) */
1863         /* This disconnects the IRQ request signal to the ISA bus */
1864         /* on the ISA adapter. This has no effect for the PCI adapter */
1865         usc_OutReg(info, PCR, (u16)((usc_InReg(info, PCR) | BIT13) | BIT12));
1866         
1867         if (!info->tty || info->tty->termios->c_cflag & HUPCL) {
1868                 info->serial_signals &= ~(SerialSignal_DTR + SerialSignal_RTS);
1869                 usc_set_serial_signals(info);
1870         }
1871         
1872         spin_unlock_irqrestore(&info->irq_spinlock,flags);
1873
1874         mgsl_release_resources(info);   
1875         
1876         if (info->tty)
1877                 set_bit(TTY_IO_ERROR, &info->tty->flags);
1878
1879         info->flags &= ~ASYNC_INITIALIZED;
1880         
1881 }       /* end of shutdown() */
1882
1883 static void mgsl_program_hw(struct mgsl_struct *info)
1884 {
1885         unsigned long flags;
1886
1887         spin_lock_irqsave(&info->irq_spinlock,flags);
1888         
1889         usc_stop_receiver(info);
1890         usc_stop_transmitter(info);
1891         info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
1892         
1893         if (info->params.mode == MGSL_MODE_HDLC ||
1894             info->params.mode == MGSL_MODE_RAW ||
1895             info->netcount)
1896                 usc_set_sync_mode(info);
1897         else
1898                 usc_set_async_mode(info);
1899                 
1900         usc_set_serial_signals(info);
1901         
1902         info->dcd_chkcount = 0;
1903         info->cts_chkcount = 0;
1904         info->ri_chkcount = 0;
1905         info->dsr_chkcount = 0;
1906
1907         usc_EnableStatusIrqs(info,SICR_CTS+SICR_DSR+SICR_DCD+SICR_RI);          
1908         usc_EnableInterrupts(info, IO_PIN);
1909         usc_get_serial_signals(info);
1910                 
1911         if (info->netcount || info->tty->termios->c_cflag & CREAD)
1912                 usc_start_receiver(info);
1913                 
1914         spin_unlock_irqrestore(&info->irq_spinlock,flags);
1915 }
1916
1917 /* Reconfigure adapter based on new parameters
1918  */
1919 static void mgsl_change_params(struct mgsl_struct *info)
1920 {
1921         unsigned cflag;
1922         int bits_per_char;
1923
1924         if (!info->tty || !info->tty->termios)
1925                 return;
1926                 
1927         if (debug_level >= DEBUG_LEVEL_INFO)
1928                 printk("%s(%d):mgsl_change_params(%s)\n",
1929                          __FILE__,__LINE__, info->device_name );
1930                          
1931         cflag = info->tty->termios->c_cflag;
1932
1933         /* if B0 rate (hangup) specified then negate DTR and RTS */
1934         /* otherwise assert DTR and RTS */
1935         if (cflag & CBAUD)
1936                 info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
1937         else
1938                 info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
1939         
1940         /* byte size and parity */
1941         
1942         switch (cflag & CSIZE) {
1943               case CS5: info->params.data_bits = 5; break;
1944               case CS6: info->params.data_bits = 6; break;
1945               case CS7: info->params.data_bits = 7; break;
1946               case CS8: info->params.data_bits = 8; break;
1947               /* Never happens, but GCC is too dumb to figure it out */
1948               default:  info->params.data_bits = 7; break;
1949               }
1950               
1951         if (cflag & CSTOPB)
1952                 info->params.stop_bits = 2;
1953         else
1954                 info->params.stop_bits = 1;
1955
1956         info->params.parity = ASYNC_PARITY_NONE;
1957         if (cflag & PARENB) {
1958                 if (cflag & PARODD)
1959                         info->params.parity = ASYNC_PARITY_ODD;
1960                 else
1961                         info->params.parity = ASYNC_PARITY_EVEN;
1962 #ifdef CMSPAR
1963                 if (cflag & CMSPAR)
1964                         info->params.parity = ASYNC_PARITY_SPACE;
1965 #endif
1966         }
1967
1968         /* calculate number of jiffies to transmit a full
1969          * FIFO (32 bytes) at specified data rate
1970          */
1971         bits_per_char = info->params.data_bits + 
1972                         info->params.stop_bits + 1;
1973
1974         /* if port data rate is set to 460800 or less then
1975          * allow tty settings to override, otherwise keep the
1976          * current data rate.
1977          */
1978         if (info->params.data_rate <= 460800)
1979                 info->params.data_rate = tty_get_baud_rate(info->tty);
1980         
1981         if ( info->params.data_rate ) {
1982                 info->timeout = (32*HZ*bits_per_char) / 
1983                                 info->params.data_rate;
1984         }
1985         info->timeout += HZ/50;         /* Add .02 seconds of slop */
1986
1987         if (cflag & CRTSCTS)
1988                 info->flags |= ASYNC_CTS_FLOW;
1989         else
1990                 info->flags &= ~ASYNC_CTS_FLOW;
1991                 
1992         if (cflag & CLOCAL)
1993                 info->flags &= ~ASYNC_CHECK_CD;
1994         else
1995                 info->flags |= ASYNC_CHECK_CD;
1996
1997         /* process tty input control flags */
1998         
1999         info->read_status_mask = RXSTATUS_OVERRUN;
2000         if (I_INPCK(info->tty))
2001                 info->read_status_mask |= RXSTATUS_PARITY_ERROR | RXSTATUS_FRAMING_ERROR;
2002         if (I_BRKINT(info->tty) || I_PARMRK(info->tty))
2003                 info->read_status_mask |= RXSTATUS_BREAK_RECEIVED;
2004         
2005         if (I_IGNPAR(info->tty))
2006                 info->ignore_status_mask |= RXSTATUS_PARITY_ERROR | RXSTATUS_FRAMING_ERROR;
2007         if (I_IGNBRK(info->tty)) {
2008                 info->ignore_status_mask |= RXSTATUS_BREAK_RECEIVED;
2009                 /* If ignoring parity and break indicators, ignore 
2010                  * overruns too.  (For real raw support).
2011                  */
2012                 if (I_IGNPAR(info->tty))
2013                         info->ignore_status_mask |= RXSTATUS_OVERRUN;
2014         }
2015
2016         mgsl_program_hw(info);
2017
2018 }       /* end of mgsl_change_params() */
2019
2020 /* mgsl_put_char()
2021  * 
2022  *      Add a character to the transmit buffer.
2023  *      
2024  * Arguments:           tty     pointer to tty information structure
2025  *                      ch      character to add to transmit buffer
2026  *              
2027  * Return Value:        None
2028  */
2029 static void mgsl_put_char(struct tty_struct *tty, unsigned char ch)
2030 {
2031         struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
2032         unsigned long flags;
2033
2034         if ( debug_level >= DEBUG_LEVEL_INFO ) {
2035                 printk( "%s(%d):mgsl_put_char(%d) on %s\n",
2036                         __FILE__,__LINE__,ch,info->device_name);
2037         }               
2038         
2039         if (mgsl_paranoia_check(info, tty->name, "mgsl_put_char"))
2040                 return;
2041
2042         if (!tty || !info->xmit_buf)
2043                 return;
2044
2045         spin_lock_irqsave(&info->irq_spinlock,flags);
2046         
2047         if ( (info->params.mode == MGSL_MODE_ASYNC ) || !info->tx_active ) {
2048         
2049                 if (info->xmit_cnt < SERIAL_XMIT_SIZE - 1) {
2050                         info->xmit_buf[info->xmit_head++] = ch;
2051                         info->xmit_head &= SERIAL_XMIT_SIZE-1;
2052                         info->xmit_cnt++;
2053                 }
2054         }
2055         
2056         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2057         
2058 }       /* end of mgsl_put_char() */
2059
2060 /* mgsl_flush_chars()
2061  * 
2062  *      Enable transmitter so remaining characters in the
2063  *      transmit buffer are sent.
2064  *      
2065  * Arguments:           tty     pointer to tty information structure
2066  * Return Value:        None
2067  */
2068 static void mgsl_flush_chars(struct tty_struct *tty)
2069 {
2070         struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
2071         unsigned long flags;
2072                                 
2073         if ( debug_level >= DEBUG_LEVEL_INFO )
2074                 printk( "%s(%d):mgsl_flush_chars() entry on %s xmit_cnt=%d\n",
2075                         __FILE__,__LINE__,info->device_name,info->xmit_cnt);
2076         
2077         if (mgsl_paranoia_check(info, tty->name, "mgsl_flush_chars"))
2078                 return;
2079
2080         if (info->xmit_cnt <= 0 || tty->stopped || tty->hw_stopped ||
2081             !info->xmit_buf)
2082                 return;
2083
2084         if ( debug_level >= DEBUG_LEVEL_INFO )
2085                 printk( "%s(%d):mgsl_flush_chars() entry on %s starting transmitter\n",
2086                         __FILE__,__LINE__,info->device_name );
2087
2088         spin_lock_irqsave(&info->irq_spinlock,flags);
2089         
2090         if (!info->tx_active) {
2091                 if ( (info->params.mode == MGSL_MODE_HDLC ||
2092                         info->params.mode == MGSL_MODE_RAW) && info->xmit_cnt ) {
2093                         /* operating in synchronous (frame oriented) mode */
2094                         /* copy data from circular xmit_buf to */
2095                         /* transmit DMA buffer. */
2096                         mgsl_load_tx_dma_buffer(info,
2097                                  info->xmit_buf,info->xmit_cnt);
2098                 }
2099                 usc_start_transmitter(info);
2100         }
2101         
2102         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2103         
2104 }       /* end of mgsl_flush_chars() */
2105
2106 /* mgsl_write()
2107  * 
2108  *      Send a block of data
2109  *      
2110  * Arguments:
2111  * 
2112  *      tty             pointer to tty information structure
2113  *      buf             pointer to buffer containing send data
2114  *      count           size of send data in bytes
2115  *      
2116  * Return Value:        number of characters written
2117  */
2118 static int mgsl_write(struct tty_struct * tty,
2119                     const unsigned char *buf, int count)
2120 {
2121         int     c, ret = 0;
2122         struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
2123         unsigned long flags;
2124         
2125         if ( debug_level >= DEBUG_LEVEL_INFO )
2126                 printk( "%s(%d):mgsl_write(%s) count=%d\n",
2127                         __FILE__,__LINE__,info->device_name,count);
2128         
2129         if (mgsl_paranoia_check(info, tty->name, "mgsl_write"))
2130                 goto cleanup;
2131
2132         if (!tty || !info->xmit_buf)
2133                 goto cleanup;
2134
2135         if ( info->params.mode == MGSL_MODE_HDLC ||
2136                         info->params.mode == MGSL_MODE_RAW ) {
2137                 /* operating in synchronous (frame oriented) mode */
2138                 /* operating in synchronous (frame oriented) mode */
2139                 if (info->tx_active) {
2140
2141                         if ( info->params.mode == MGSL_MODE_HDLC ) {
2142                                 ret = 0;
2143                                 goto cleanup;
2144                         }
2145                         /* transmitter is actively sending data -
2146                          * if we have multiple transmit dma and
2147                          * holding buffers, attempt to queue this
2148                          * frame for transmission at a later time.
2149                          */
2150                         if (info->tx_holding_count >= info->num_tx_holding_buffers ) {
2151                                 /* no tx holding buffers available */
2152                                 ret = 0;
2153                                 goto cleanup;
2154                         }
2155
2156                         /* queue transmit frame request */
2157                         ret = count;
2158                         save_tx_buffer_request(info,buf,count);
2159
2160                         /* if we have sufficient tx dma buffers,
2161                          * load the next buffered tx request
2162                          */
2163                         spin_lock_irqsave(&info->irq_spinlock,flags);
2164                         load_next_tx_holding_buffer(info);
2165                         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2166                         goto cleanup;
2167                 }
2168         
2169                 /* if operating in HDLC LoopMode and the adapter  */
2170                 /* has yet to be inserted into the loop, we can't */
2171                 /* transmit                                       */
2172
2173                 if ( (info->params.flags & HDLC_FLAG_HDLC_LOOPMODE) &&
2174                         !usc_loopmode_active(info) )
2175                 {
2176                         ret = 0;
2177                         goto cleanup;
2178                 }
2179
2180                 if ( info->xmit_cnt ) {
2181                         /* Send accumulated from send_char() calls */
2182                         /* as frame and wait before accepting more data. */
2183                         ret = 0;
2184                         
2185                         /* copy data from circular xmit_buf to */
2186                         /* transmit DMA buffer. */
2187                         mgsl_load_tx_dma_buffer(info,
2188                                 info->xmit_buf,info->xmit_cnt);
2189                         if ( debug_level >= DEBUG_LEVEL_INFO )
2190                                 printk( "%s(%d):mgsl_write(%s) sync xmit_cnt flushing\n",
2191                                         __FILE__,__LINE__,info->device_name);
2192                 } else {
2193                         if ( debug_level >= DEBUG_LEVEL_INFO )
2194                                 printk( "%s(%d):mgsl_write(%s) sync transmit accepted\n",
2195                                         __FILE__,__LINE__,info->device_name);
2196                         ret = count;
2197                         info->xmit_cnt = count;
2198                         mgsl_load_tx_dma_buffer(info,buf,count);
2199                 }
2200         } else {
2201                 while (1) {
2202                         spin_lock_irqsave(&info->irq_spinlock,flags);
2203                         c = min_t(int, count,
2204                                 min(SERIAL_XMIT_SIZE - info->xmit_cnt - 1,
2205                                     SERIAL_XMIT_SIZE - info->xmit_head));
2206                         if (c <= 0) {
2207                                 spin_unlock_irqrestore(&info->irq_spinlock,flags);
2208                                 break;
2209                         }
2210                         memcpy(info->xmit_buf + info->xmit_head, buf, c);
2211                         info->xmit_head = ((info->xmit_head + c) &
2212                                            (SERIAL_XMIT_SIZE-1));
2213                         info->xmit_cnt += c;
2214                         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2215                         buf += c;
2216                         count -= c;
2217                         ret += c;
2218                 }
2219         }       
2220         
2221         if (info->xmit_cnt && !tty->stopped && !tty->hw_stopped) {
2222                 spin_lock_irqsave(&info->irq_spinlock,flags);
2223                 if (!info->tx_active)
2224                         usc_start_transmitter(info);
2225                 spin_unlock_irqrestore(&info->irq_spinlock,flags);
2226         }
2227 cleanup:        
2228         if ( debug_level >= DEBUG_LEVEL_INFO )
2229                 printk( "%s(%d):mgsl_write(%s) returning=%d\n",
2230                         __FILE__,__LINE__,info->device_name,ret);
2231                         
2232         return ret;
2233         
2234 }       /* end of mgsl_write() */
2235
2236 /* mgsl_write_room()
2237  *
2238  *      Return the count of free bytes in transmit buffer
2239  *      
2240  * Arguments:           tty     pointer to tty info structure
2241  * Return Value:        None
2242  */
2243 static int mgsl_write_room(struct tty_struct *tty)
2244 {
2245         struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
2246         int     ret;
2247                                 
2248         if (mgsl_paranoia_check(info, tty->name, "mgsl_write_room"))
2249                 return 0;
2250         ret = SERIAL_XMIT_SIZE - info->xmit_cnt - 1;
2251         if (ret < 0)
2252                 ret = 0;
2253                 
2254         if (debug_level >= DEBUG_LEVEL_INFO)
2255                 printk("%s(%d):mgsl_write_room(%s)=%d\n",
2256                          __FILE__,__LINE__, info->device_name,ret );
2257                          
2258         if ( info->params.mode == MGSL_MODE_HDLC ||
2259                 info->params.mode == MGSL_MODE_RAW ) {
2260                 /* operating in synchronous (frame oriented) mode */
2261                 if ( info->tx_active )
2262                         return 0;
2263                 else
2264                         return HDLC_MAX_FRAME_SIZE;
2265         }
2266         
2267         return ret;
2268         
2269 }       /* end of mgsl_write_room() */
2270
2271 /* mgsl_chars_in_buffer()
2272  *
2273  *      Return the count of bytes in transmit buffer
2274  *      
2275  * Arguments:           tty     pointer to tty info structure
2276  * Return Value:        None
2277  */
2278 static int mgsl_chars_in_buffer(struct tty_struct *tty)
2279 {
2280         struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
2281                          
2282         if (debug_level >= DEBUG_LEVEL_INFO)
2283                 printk("%s(%d):mgsl_chars_in_buffer(%s)\n",
2284                          __FILE__,__LINE__, info->device_name );
2285                          
2286         if (mgsl_paranoia_check(info, tty->name, "mgsl_chars_in_buffer"))
2287                 return 0;
2288                 
2289         if (debug_level >= DEBUG_LEVEL_INFO)
2290                 printk("%s(%d):mgsl_chars_in_buffer(%s)=%d\n",
2291                          __FILE__,__LINE__, info->device_name,info->xmit_cnt );
2292                          
2293         if ( info->params.mode == MGSL_MODE_HDLC ||
2294                 info->params.mode == MGSL_MODE_RAW ) {
2295                 /* operating in synchronous (frame oriented) mode */
2296                 if ( info->tx_active )
2297                         return info->max_frame_size;
2298                 else
2299                         return 0;
2300         }
2301                          
2302         return info->xmit_cnt;
2303 }       /* end of mgsl_chars_in_buffer() */
2304
2305 /* mgsl_flush_buffer()
2306  *
2307  *      Discard all data in the send buffer
2308  *      
2309  * Arguments:           tty     pointer to tty info structure
2310  * Return Value:        None
2311  */
2312 static void mgsl_flush_buffer(struct tty_struct *tty)
2313 {
2314         struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
2315         unsigned long flags;
2316         
2317         if (debug_level >= DEBUG_LEVEL_INFO)
2318                 printk("%s(%d):mgsl_flush_buffer(%s) entry\n",
2319                          __FILE__,__LINE__, info->device_name );
2320         
2321         if (mgsl_paranoia_check(info, tty->name, "mgsl_flush_buffer"))
2322                 return;
2323                 
2324         spin_lock_irqsave(&info->irq_spinlock,flags); 
2325         info->xmit_cnt = info->xmit_head = info->xmit_tail = 0;
2326         del_timer(&info->tx_timer);     
2327         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2328         
2329         tty_wakeup(tty);
2330 }
2331
2332 /* mgsl_send_xchar()
2333  *
2334  *      Send a high-priority XON/XOFF character
2335  *      
2336  * Arguments:           tty     pointer to tty info structure
2337  *                      ch      character to send
2338  * Return Value:        None
2339  */
2340 static void mgsl_send_xchar(struct tty_struct *tty, char ch)
2341 {
2342         struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
2343         unsigned long flags;
2344
2345         if (debug_level >= DEBUG_LEVEL_INFO)
2346                 printk("%s(%d):mgsl_send_xchar(%s,%d)\n",
2347                          __FILE__,__LINE__, info->device_name, ch );
2348                          
2349         if (mgsl_paranoia_check(info, tty->name, "mgsl_send_xchar"))
2350                 return;
2351
2352         info->x_char = ch;
2353         if (ch) {
2354                 /* Make sure transmit interrupts are on */
2355                 spin_lock_irqsave(&info->irq_spinlock,flags);
2356                 if (!info->tx_enabled)
2357                         usc_start_transmitter(info);
2358                 spin_unlock_irqrestore(&info->irq_spinlock,flags);
2359         }
2360 }       /* end of mgsl_send_xchar() */
2361
2362 /* mgsl_throttle()
2363  * 
2364  *      Signal remote device to throttle send data (our receive data)
2365  *      
2366  * Arguments:           tty     pointer to tty info structure
2367  * Return Value:        None
2368  */
2369 static void mgsl_throttle(struct tty_struct * tty)
2370 {
2371         struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
2372         unsigned long flags;
2373         
2374         if (debug_level >= DEBUG_LEVEL_INFO)
2375                 printk("%s(%d):mgsl_throttle(%s) entry\n",
2376                          __FILE__,__LINE__, info->device_name );
2377
2378         if (mgsl_paranoia_check(info, tty->name, "mgsl_throttle"))
2379                 return;
2380         
2381         if (I_IXOFF(tty))
2382                 mgsl_send_xchar(tty, STOP_CHAR(tty));
2383  
2384         if (tty->termios->c_cflag & CRTSCTS) {
2385                 spin_lock_irqsave(&info->irq_spinlock,flags);
2386                 info->serial_signals &= ~SerialSignal_RTS;
2387                 usc_set_serial_signals(info);
2388                 spin_unlock_irqrestore(&info->irq_spinlock,flags);
2389         }
2390 }       /* end of mgsl_throttle() */
2391
2392 /* mgsl_unthrottle()
2393  * 
2394  *      Signal remote device to stop throttling send data (our receive data)
2395  *      
2396  * Arguments:           tty     pointer to tty info structure
2397  * Return Value:        None
2398  */
2399 static void mgsl_unthrottle(struct tty_struct * tty)
2400 {
2401         struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
2402         unsigned long flags;
2403         
2404         if (debug_level >= DEBUG_LEVEL_INFO)
2405                 printk("%s(%d):mgsl_unthrottle(%s) entry\n",
2406                          __FILE__,__LINE__, info->device_name );
2407
2408         if (mgsl_paranoia_check(info, tty->name, "mgsl_unthrottle"))
2409                 return;
2410         
2411         if (I_IXOFF(tty)) {
2412                 if (info->x_char)
2413                         info->x_char = 0;
2414                 else
2415                         mgsl_send_xchar(tty, START_CHAR(tty));
2416         }
2417         
2418         if (tty->termios->c_cflag & CRTSCTS) {
2419                 spin_lock_irqsave(&info->irq_spinlock,flags);
2420                 info->serial_signals |= SerialSignal_RTS;
2421                 usc_set_serial_signals(info);
2422                 spin_unlock_irqrestore(&info->irq_spinlock,flags);
2423         }
2424         
2425 }       /* end of mgsl_unthrottle() */
2426
2427 /* mgsl_get_stats()
2428  * 
2429  *      get the current serial parameters information
2430  *
2431  * Arguments:   info            pointer to device instance data
2432  *              user_icount     pointer to buffer to hold returned stats
2433  *      
2434  * Return Value:        0 if success, otherwise error code
2435  */
2436 static int mgsl_get_stats(struct mgsl_struct * info, struct mgsl_icount __user *user_icount)
2437 {
2438         int err;
2439         
2440         if (debug_level >= DEBUG_LEVEL_INFO)
2441                 printk("%s(%d):mgsl_get_params(%s)\n",
2442                          __FILE__,__LINE__, info->device_name);
2443                         
2444         if (!user_icount) {
2445                 memset(&info->icount, 0, sizeof(info->icount));
2446         } else {
2447                 COPY_TO_USER(err, user_icount, &info->icount, sizeof(struct mgsl_icount));
2448                 if (err)
2449                         return -EFAULT;
2450         }
2451         
2452         return 0;
2453         
2454 }       /* end of mgsl_get_stats() */
2455
2456 /* mgsl_get_params()
2457  * 
2458  *      get the current serial parameters information
2459  *
2460  * Arguments:   info            pointer to device instance data
2461  *              user_params     pointer to buffer to hold returned params
2462  *      
2463  * Return Value:        0 if success, otherwise error code
2464  */
2465 static int mgsl_get_params(struct mgsl_struct * info, MGSL_PARAMS __user *user_params)
2466 {
2467         int err;
2468         if (debug_level >= DEBUG_LEVEL_INFO)
2469                 printk("%s(%d):mgsl_get_params(%s)\n",
2470                          __FILE__,__LINE__, info->device_name);
2471                         
2472         COPY_TO_USER(err,user_params, &info->params, sizeof(MGSL_PARAMS));
2473         if (err) {
2474                 if ( debug_level >= DEBUG_LEVEL_INFO )
2475                         printk( "%s(%d):mgsl_get_params(%s) user buffer copy failed\n",
2476                                 __FILE__,__LINE__,info->device_name);
2477                 return -EFAULT;
2478         }
2479         
2480         return 0;
2481         
2482 }       /* end of mgsl_get_params() */
2483
2484 /* mgsl_set_params()
2485  * 
2486  *      set the serial parameters
2487  *      
2488  * Arguments:
2489  * 
2490  *      info            pointer to device instance data
2491  *      new_params      user buffer containing new serial params
2492  *
2493  * Return Value:        0 if success, otherwise error code
2494  */
2495 static int mgsl_set_params(struct mgsl_struct * info, MGSL_PARAMS __user *new_params)
2496 {
2497         unsigned long flags;
2498         MGSL_PARAMS tmp_params;
2499         int err;
2500  
2501         if (debug_level >= DEBUG_LEVEL_INFO)
2502                 printk("%s(%d):mgsl_set_params %s\n", __FILE__,__LINE__,
2503                         info->device_name );
2504         COPY_FROM_USER(err,&tmp_params, new_params, sizeof(MGSL_PARAMS));
2505         if (err) {
2506                 if ( debug_level >= DEBUG_LEVEL_INFO )
2507                         printk( "%s(%d):mgsl_set_params(%s) user buffer copy failed\n",
2508                                 __FILE__,__LINE__,info->device_name);
2509                 return -EFAULT;
2510         }
2511         
2512         spin_lock_irqsave(&info->irq_spinlock,flags);
2513         memcpy(&info->params,&tmp_params,sizeof(MGSL_PARAMS));
2514         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2515         
2516         mgsl_change_params(info);
2517         
2518         return 0;
2519         
2520 }       /* end of mgsl_set_params() */
2521
2522 /* mgsl_get_txidle()
2523  * 
2524  *      get the current transmit idle mode
2525  *
2526  * Arguments:   info            pointer to device instance data
2527  *              idle_mode       pointer to buffer to hold returned idle mode
2528  *      
2529  * Return Value:        0 if success, otherwise error code
2530  */
2531 static int mgsl_get_txidle(struct mgsl_struct * info, int __user *idle_mode)
2532 {
2533         int err;
2534         
2535         if (debug_level >= DEBUG_LEVEL_INFO)
2536                 printk("%s(%d):mgsl_get_txidle(%s)=%d\n",
2537                          __FILE__,__LINE__, info->device_name, info->idle_mode);
2538                         
2539         COPY_TO_USER(err,idle_mode, &info->idle_mode, sizeof(int));
2540         if (err) {
2541                 if ( debug_level >= DEBUG_LEVEL_INFO )
2542                         printk( "%s(%d):mgsl_get_txidle(%s) user buffer copy failed\n",
2543                                 __FILE__,__LINE__,info->device_name);
2544                 return -EFAULT;
2545         }
2546         
2547         return 0;
2548         
2549 }       /* end of mgsl_get_txidle() */
2550
2551 /* mgsl_set_txidle()    service ioctl to set transmit idle mode
2552  *      
2553  * Arguments:           info            pointer to device instance data
2554  *                      idle_mode       new idle mode
2555  *
2556  * Return Value:        0 if success, otherwise error code
2557  */
2558 static int mgsl_set_txidle(struct mgsl_struct * info, int idle_mode)
2559 {
2560         unsigned long flags;
2561  
2562         if (debug_level >= DEBUG_LEVEL_INFO)
2563                 printk("%s(%d):mgsl_set_txidle(%s,%d)\n", __FILE__,__LINE__,
2564                         info->device_name, idle_mode );
2565                         
2566         spin_lock_irqsave(&info->irq_spinlock,flags);
2567         info->idle_mode = idle_mode;
2568         usc_set_txidle( info );
2569         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2570         return 0;
2571         
2572 }       /* end of mgsl_set_txidle() */
2573
2574 /* mgsl_txenable()
2575  * 
2576  *      enable or disable the transmitter
2577  *      
2578  * Arguments:
2579  * 
2580  *      info            pointer to device instance data
2581  *      enable          1 = enable, 0 = disable
2582  *
2583  * Return Value:        0 if success, otherwise error code
2584  */
2585 static int mgsl_txenable(struct mgsl_struct * info, int enable)
2586 {
2587         unsigned long flags;
2588  
2589         if (debug_level >= DEBUG_LEVEL_INFO)
2590                 printk("%s(%d):mgsl_txenable(%s,%d)\n", __FILE__,__LINE__,
2591                         info->device_name, enable);
2592                         
2593         spin_lock_irqsave(&info->irq_spinlock,flags);
2594         if ( enable ) {
2595                 if ( !info->tx_enabled ) {
2596
2597                         usc_start_transmitter(info);
2598                         /*--------------------------------------------------
2599                          * if HDLC/SDLC Loop mode, attempt to insert the
2600                          * station in the 'loop' by setting CMR:13. Upon
2601                          * receipt of the next GoAhead (RxAbort) sequence,
2602                          * the OnLoop indicator (CCSR:7) should go active
2603                          * to indicate that we are on the loop
2604                          *--------------------------------------------------*/
2605                         if ( info->params.flags & HDLC_FLAG_HDLC_LOOPMODE )
2606                                 usc_loopmode_insert_request( info );
2607                 }
2608         } else {
2609                 if ( info->tx_enabled )
2610                         usc_stop_transmitter(info);
2611         }
2612         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2613         return 0;
2614         
2615 }       /* end of mgsl_txenable() */
2616
2617 /* mgsl_txabort()       abort send HDLC frame
2618  *      
2619  * Arguments:           info            pointer to device instance data
2620  * Return Value:        0 if success, otherwise error code
2621  */
2622 static int mgsl_txabort(struct mgsl_struct * info)
2623 {
2624         unsigned long flags;
2625  
2626         if (debug_level >= DEBUG_LEVEL_INFO)
2627                 printk("%s(%d):mgsl_txabort(%s)\n", __FILE__,__LINE__,
2628                         info->device_name);
2629                         
2630         spin_lock_irqsave(&info->irq_spinlock,flags);
2631         if ( info->tx_active && info->params.mode == MGSL_MODE_HDLC )
2632         {
2633                 if ( info->params.flags & HDLC_FLAG_HDLC_LOOPMODE )
2634                         usc_loopmode_cancel_transmit( info );
2635                 else
2636                         usc_TCmd(info,TCmd_SendAbort);
2637         }
2638         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2639         return 0;
2640         
2641 }       /* end of mgsl_txabort() */
2642
2643 /* mgsl_rxenable()      enable or disable the receiver
2644  *      
2645  * Arguments:           info            pointer to device instance data
2646  *                      enable          1 = enable, 0 = disable
2647  * Return Value:        0 if success, otherwise error code
2648  */
2649 static int mgsl_rxenable(struct mgsl_struct * info, int enable)
2650 {
2651         unsigned long flags;
2652  
2653         if (debug_level >= DEBUG_LEVEL_INFO)
2654                 printk("%s(%d):mgsl_rxenable(%s,%d)\n", __FILE__,__LINE__,
2655                         info->device_name, enable);
2656                         
2657         spin_lock_irqsave(&info->irq_spinlock,flags);
2658         if ( enable ) {
2659                 if ( !info->rx_enabled )
2660                         usc_start_receiver(info);
2661         } else {
2662                 if ( info->rx_enabled )
2663                         usc_stop_receiver(info);
2664         }
2665         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2666         return 0;
2667         
2668 }       /* end of mgsl_rxenable() */
2669
2670 /* mgsl_wait_event()    wait for specified event to occur
2671  *      
2672  * Arguments:           info    pointer to device instance data
2673  *                      mask    pointer to bitmask of events to wait for
2674  * Return Value:        0       if successful and bit mask updated with
2675  *                              of events triggerred,
2676  *                      otherwise error code
2677  */
2678 static int mgsl_wait_event(struct mgsl_struct * info, int __user * mask_ptr)
2679 {
2680         unsigned long flags;
2681         int s;
2682         int rc=0;
2683         struct mgsl_icount cprev, cnow;
2684         int events;
2685         int mask;
2686         struct  _input_signal_events oldsigs, newsigs;
2687         DECLARE_WAITQUEUE(wait, current);
2688
2689         COPY_FROM_USER(rc,&mask, mask_ptr, sizeof(int));
2690         if (rc) {
2691                 return  -EFAULT;
2692         }
2693                  
2694         if (debug_level >= DEBUG_LEVEL_INFO)
2695                 printk("%s(%d):mgsl_wait_event(%s,%d)\n", __FILE__,__LINE__,
2696                         info->device_name, mask);
2697
2698         spin_lock_irqsave(&info->irq_spinlock,flags);
2699
2700         /* return immediately if state matches requested events */
2701         usc_get_serial_signals(info);
2702         s = info->serial_signals;
2703         events = mask &
2704                 ( ((s & SerialSignal_DSR) ? MgslEvent_DsrActive:MgslEvent_DsrInactive) +
2705                   ((s & SerialSignal_DCD) ? MgslEvent_DcdActive:MgslEvent_DcdInactive) +
2706                   ((s & SerialSignal_CTS) ? MgslEvent_CtsActive:MgslEvent_CtsInactive) +
2707                   ((s & SerialSignal_RI)  ? MgslEvent_RiActive :MgslEvent_RiInactive) );
2708         if (events) {
2709                 spin_unlock_irqrestore(&info->irq_spinlock,flags);
2710                 goto exit;
2711         }
2712
2713         /* save current irq counts */
2714         cprev = info->icount;
2715         oldsigs = info->input_signal_events;
2716         
2717         /* enable hunt and idle irqs if needed */
2718         if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2719                 u16 oldreg = usc_InReg(info,RICR);
2720                 u16 newreg = oldreg +
2721                          (mask & MgslEvent_ExitHuntMode ? RXSTATUS_EXITED_HUNT:0) +
2722                          (mask & MgslEvent_IdleReceived ? RXSTATUS_IDLE_RECEIVED:0);
2723                 if (oldreg != newreg)
2724                         usc_OutReg(info, RICR, newreg);
2725         }
2726         
2727         set_current_state(TASK_INTERRUPTIBLE);
2728         add_wait_queue(&info->event_wait_q, &wait);
2729         
2730         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2731         
2732
2733         for(;;) {
2734                 schedule();
2735                 if (signal_pending(current)) {
2736                         rc = -ERESTARTSYS;
2737                         break;
2738                 }
2739                         
2740                 /* get current irq counts */
2741                 spin_lock_irqsave(&info->irq_spinlock,flags);
2742                 cnow = info->icount;
2743                 newsigs = info->input_signal_events;
2744                 set_current_state(TASK_INTERRUPTIBLE);
2745                 spin_unlock_irqrestore(&info->irq_spinlock,flags);
2746
2747                 /* if no change, wait aborted for some reason */
2748                 if (newsigs.dsr_up   == oldsigs.dsr_up   &&
2749                     newsigs.dsr_down == oldsigs.dsr_down &&
2750                     newsigs.dcd_up   == oldsigs.dcd_up   &&
2751                     newsigs.dcd_down == oldsigs.dcd_down &&
2752                     newsigs.cts_up   == oldsigs.cts_up   &&
2753                     newsigs.cts_down == oldsigs.cts_down &&
2754                     newsigs.ri_up    == oldsigs.ri_up    &&
2755                     newsigs.ri_down  == oldsigs.ri_down  &&
2756                     cnow.exithunt    == cprev.exithunt   &&
2757                     cnow.rxidle      == cprev.rxidle) {
2758                         rc = -EIO;
2759                         break;
2760                 }
2761
2762                 events = mask &
2763                         ( (newsigs.dsr_up   != oldsigs.dsr_up   ? MgslEvent_DsrActive:0)   +
2764                         (newsigs.dsr_down != oldsigs.dsr_down ? MgslEvent_DsrInactive:0) +
2765                         (newsigs.dcd_up   != oldsigs.dcd_up   ? MgslEvent_DcdActive:0)   +
2766                         (newsigs.dcd_down != oldsigs.dcd_down ? MgslEvent_DcdInactive:0) +
2767                         (newsigs.cts_up   != oldsigs.cts_up   ? MgslEvent_CtsActive:0)   +
2768                         (newsigs.cts_down != oldsigs.cts_down ? MgslEvent_CtsInactive:0) +
2769                         (newsigs.ri_up    != oldsigs.ri_up    ? MgslEvent_RiActive:0)    +
2770                         (newsigs.ri_down  != oldsigs.ri_down  ? MgslEvent_RiInactive:0)  +
2771                         (cnow.exithunt    != cprev.exithunt   ? MgslEvent_ExitHuntMode:0) +
2772                           (cnow.rxidle      != cprev.rxidle     ? MgslEvent_IdleReceived:0) );
2773                 if (events)
2774                         break;
2775                 
2776                 cprev = cnow;
2777                 oldsigs = newsigs;
2778         }
2779         
2780         remove_wait_queue(&info->event_wait_q, &wait);
2781         set_current_state(TASK_RUNNING);
2782
2783         if (mask & (MgslEvent_ExitHuntMode + MgslEvent_IdleReceived)) {
2784                 spin_lock_irqsave(&info->irq_spinlock,flags);
2785                 if (!waitqueue_active(&info->event_wait_q)) {
2786                         /* disable enable exit hunt mode/idle rcvd IRQs */
2787                         usc_OutReg(info, RICR, usc_InReg(info,RICR) &
2788                                 ~(RXSTATUS_EXITED_HUNT + RXSTATUS_IDLE_RECEIVED));
2789                 }
2790                 spin_unlock_irqrestore(&info->irq_spinlock,flags);
2791         }
2792 exit:
2793         if ( rc == 0 )
2794                 PUT_USER(rc, events, mask_ptr);
2795                 
2796         return rc;
2797         
2798 }       /* end of mgsl_wait_event() */
2799
2800 static int modem_input_wait(struct mgsl_struct *info,int arg)
2801 {
2802         unsigned long flags;
2803         int rc;
2804         struct mgsl_icount cprev, cnow;
2805         DECLARE_WAITQUEUE(wait, current);
2806
2807         /* save current irq counts */
2808         spin_lock_irqsave(&info->irq_spinlock,flags);
2809         cprev = info->icount;
2810         add_wait_queue(&info->status_event_wait_q, &wait);
2811         set_current_state(TASK_INTERRUPTIBLE);
2812         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2813
2814         for(;;) {
2815                 schedule();
2816                 if (signal_pending(current)) {
2817                         rc = -ERESTARTSYS;
2818                         break;
2819                 }
2820
2821                 /* get new irq counts */
2822                 spin_lock_irqsave(&info->irq_spinlock,flags);
2823                 cnow = info->icount;
2824                 set_current_state(TASK_INTERRUPTIBLE);
2825                 spin_unlock_irqrestore(&info->irq_spinlock,flags);
2826
2827                 /* if no change, wait aborted for some reason */
2828                 if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
2829                     cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) {
2830                         rc = -EIO;
2831                         break;
2832                 }
2833
2834                 /* check for change in caller specified modem input */
2835                 if ((arg & TIOCM_RNG && cnow.rng != cprev.rng) ||
2836                     (arg & TIOCM_DSR && cnow.dsr != cprev.dsr) ||
2837                     (arg & TIOCM_CD  && cnow.dcd != cprev.dcd) ||
2838                     (arg & TIOCM_CTS && cnow.cts != cprev.cts)) {
2839                         rc = 0;
2840                         break;
2841                 }
2842
2843                 cprev = cnow;
2844         }
2845         remove_wait_queue(&info->status_event_wait_q, &wait);
2846         set_current_state(TASK_RUNNING);
2847         return rc;
2848 }
2849
2850 /* return the state of the serial control and status signals
2851  */
2852 static int tiocmget(struct tty_struct *tty, struct file *file)
2853 {
2854         struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
2855         unsigned int result;
2856         unsigned long flags;
2857
2858         spin_lock_irqsave(&info->irq_spinlock,flags);
2859         usc_get_serial_signals(info);
2860         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2861
2862         result = ((info->serial_signals & SerialSignal_RTS) ? TIOCM_RTS:0) +
2863                 ((info->serial_signals & SerialSignal_DTR) ? TIOCM_DTR:0) +
2864                 ((info->serial_signals & SerialSignal_DCD) ? TIOCM_CAR:0) +
2865                 ((info->serial_signals & SerialSignal_RI)  ? TIOCM_RNG:0) +
2866                 ((info->serial_signals & SerialSignal_DSR) ? TIOCM_DSR:0) +
2867                 ((info->serial_signals & SerialSignal_CTS) ? TIOCM_CTS:0);
2868
2869         if (debug_level >= DEBUG_LEVEL_INFO)
2870                 printk("%s(%d):%s tiocmget() value=%08X\n",
2871                          __FILE__,__LINE__, info->device_name, result );
2872         return result;
2873 }
2874
2875 /* set modem control signals (DTR/RTS)
2876  */
2877 static int tiocmset(struct tty_struct *tty, struct file *file,
2878                     unsigned int set, unsigned int clear)
2879 {
2880         struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
2881         unsigned long flags;
2882
2883         if (debug_level >= DEBUG_LEVEL_INFO)
2884                 printk("%s(%d):%s tiocmset(%x,%x)\n",
2885                         __FILE__,__LINE__,info->device_name, set, clear);
2886
2887         if (set & TIOCM_RTS)
2888                 info->serial_signals |= SerialSignal_RTS;
2889         if (set & TIOCM_DTR)
2890                 info->serial_signals |= SerialSignal_DTR;
2891         if (clear & TIOCM_RTS)
2892                 info->serial_signals &= ~SerialSignal_RTS;
2893         if (clear & TIOCM_DTR)
2894                 info->serial_signals &= ~SerialSignal_DTR;
2895
2896         spin_lock_irqsave(&info->irq_spinlock,flags);
2897         usc_set_serial_signals(info);
2898         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2899
2900         return 0;
2901 }
2902
2903 /* mgsl_break()         Set or clear transmit break condition
2904  *
2905  * Arguments:           tty             pointer to tty instance data
2906  *                      break_state     -1=set break condition, 0=clear
2907  * Return Value:        None
2908  */
2909 static void mgsl_break(struct tty_struct *tty, int break_state)
2910 {
2911         struct mgsl_struct * info = (struct mgsl_struct *)tty->driver_data;
2912         unsigned long flags;
2913         
2914         if (debug_level >= DEBUG_LEVEL_INFO)
2915                 printk("%s(%d):mgsl_break(%s,%d)\n",
2916                          __FILE__,__LINE__, info->device_name, break_state);
2917                          
2918         if (mgsl_paranoia_check(info, tty->name, "mgsl_break"))
2919                 return;
2920
2921         spin_lock_irqsave(&info->irq_spinlock,flags);
2922         if (break_state == -1)
2923                 usc_OutReg(info,IOCR,(u16)(usc_InReg(info,IOCR) | BIT7));
2924         else 
2925                 usc_OutReg(info,IOCR,(u16)(usc_InReg(info,IOCR) & ~BIT7));
2926         spin_unlock_irqrestore(&info->irq_spinlock,flags);
2927         
2928 }       /* end of mgsl_break() */
2929
2930 /* mgsl_ioctl() Service an IOCTL request
2931  *      
2932  * Arguments:
2933  * 
2934  *      tty     pointer to tty instance data
2935  *      file    pointer to associated file object for device
2936  *      cmd     IOCTL command code
2937  *      arg     command argument/context
2938  *      
2939  * Return Value:        0 if success, otherwise error code
2940  */
2941 static int mgsl_ioctl(struct tty_struct *tty, struct file * file,
2942                     unsigned int cmd, unsigned long arg)
2943 {
2944         struct mgsl_struct * info = (struct mgsl_struct *)tty->driver_data;
2945         
2946         if (debug_level >= DEBUG_LEVEL_INFO)
2947                 printk("%s(%d):mgsl_ioctl %s cmd=%08X\n", __FILE__,__LINE__,
2948                         info->device_name, cmd );
2949         
2950         if (mgsl_paranoia_check(info, tty->name, "mgsl_ioctl"))
2951                 return -ENODEV;
2952
2953         if ((cmd != TIOCGSERIAL) && (cmd != TIOCSSERIAL) &&
2954             (cmd != TIOCMIWAIT) && (cmd != TIOCGICOUNT)) {
2955                 if (tty->flags & (1 << TTY_IO_ERROR))
2956                     return -EIO;
2957         }
2958
2959         return mgsl_ioctl_common(info, cmd, arg);
2960 }
2961
2962 static int mgsl_ioctl_common(struct mgsl_struct *info, unsigned int cmd, unsigned long arg)
2963 {
2964         int error;
2965         struct mgsl_icount cnow;        /* kernel counter temps */
2966         void __user *argp = (void __user *)arg;
2967         struct serial_icounter_struct __user *p_cuser;  /* user space */
2968         unsigned long flags;
2969         
2970         switch (cmd) {
2971                 case MGSL_IOCGPARAMS:
2972                         return mgsl_get_params(info, argp);
2973                 case MGSL_IOCSPARAMS:
2974                         return mgsl_set_params(info, argp);
2975                 case MGSL_IOCGTXIDLE:
2976                         return mgsl_get_txidle(info, argp);
2977                 case MGSL_IOCSTXIDLE:
2978                         return mgsl_set_txidle(info,(int)arg);
2979                 case MGSL_IOCTXENABLE:
2980                         return mgsl_txenable(info,(int)arg);
2981                 case MGSL_IOCRXENABLE:
2982                         return mgsl_rxenable(info,(int)arg);
2983                 case MGSL_IOCTXABORT:
2984                         return mgsl_txabort(info);
2985                 case MGSL_IOCGSTATS:
2986                         return mgsl_get_stats(info, argp);
2987                 case MGSL_IOCWAITEVENT:
2988                         return mgsl_wait_event(info, argp);
2989                 case MGSL_IOCLOOPTXDONE:
2990                         return mgsl_loopmode_send_done(info);
2991                 /* Wait for modem input (DCD,RI,DSR,CTS) change
2992                  * as specified by mask in arg (TIOCM_RNG/DSR/CD/CTS)
2993                  */
2994                 case TIOCMIWAIT:
2995                         return modem_input_wait(info,(int)arg);
2996
2997                 /* 
2998                  * Get counter of input serial line interrupts (DCD,RI,DSR,CTS)
2999                  * Return: write counters to the user passed counter struct
3000                  * NB: both 1->0 and 0->1 transitions are counted except for
3001                  *     RI where only 0->1 is counted.
3002                  */
3003                 case TIOCGICOUNT:
3004                         spin_lock_irqsave(&info->irq_spinlock,flags);
3005                         cnow = info->icount;
3006                         spin_unlock_irqrestore(&info->irq_spinlock,flags);
3007                         p_cuser = argp;
3008                         PUT_USER(error,cnow.cts, &p_cuser->cts);
3009                         if (error) return error;
3010                         PUT_USER(error,cnow.dsr, &p_cuser->dsr);
3011                         if (error) return error;
3012                         PUT_USER(error,cnow.rng, &p_cuser->rng);
3013                         if (error) return error;
3014                         PUT_USER(error,cnow.dcd, &p_cuser->dcd);
3015                         if (error) return error;
3016                         PUT_USER(error,cnow.rx, &p_cuser->rx);
3017                         if (error) return error;
3018                         PUT_USER(error,cnow.tx, &p_cuser->tx);
3019                         if (error) return error;
3020                         PUT_USER(error,cnow.frame, &p_cuser->frame);
3021                         if (error) return error;
3022                         PUT_USER(error,cnow.overrun, &p_cuser->overrun);
3023                         if (error) return error;
3024                         PUT_USER(error,cnow.parity, &p_cuser->parity);
3025                         if (error) return error;
3026                         PUT_USER(error,cnow.brk, &p_cuser->brk);
3027                         if (error) return error;
3028                         PUT_USER(error,cnow.buf_overrun, &p_cuser->buf_overrun);
3029                         if (error) return error;
3030                         return 0;
3031                 default:
3032                         return -ENOIOCTLCMD;
3033         }
3034         return 0;
3035 }
3036
3037 /* mgsl_set_termios()
3038  * 
3039  *      Set new termios settings
3040  *      
3041  * Arguments:
3042  * 
3043  *      tty             pointer to tty structure
3044  *      termios         pointer to buffer to hold returned old termios
3045  *      
3046  * Return Value:                None
3047  */
3048 static void mgsl_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
3049 {
3050         struct mgsl_struct *info = (struct mgsl_struct *)tty->driver_data;
3051         unsigned long flags;
3052         
3053         if (debug_level >= DEBUG_LEVEL_INFO)
3054                 printk("%s(%d):mgsl_set_termios %s\n", __FILE__,__LINE__,
3055                         tty->driver->name );
3056         
3057         mgsl_change_params(info);
3058
3059         /* Handle transition to B0 status */
3060         if (old_termios->c_cflag & CBAUD &&
3061             !(tty->termios->c_cflag & CBAUD)) {
3062                 info->serial_signals &= ~(SerialSignal_RTS + SerialSignal_DTR);
3063                 spin_lock_irqsave(&info->irq_spinlock,flags);
3064                 usc_set_serial_signals(info);
3065                 spin_unlock_irqrestore(&info->irq_spinlock,flags);
3066         }
3067         
3068         /* Handle transition away from B0 status */
3069         if (!(old_termios->c_cflag & CBAUD) &&
3070             tty->termios->c_cflag & CBAUD) {
3071                 info->serial_signals |= SerialSignal_DTR;
3072                 if (!(tty->termios->c_cflag & CRTSCTS) || 
3073                     !test_bit(TTY_THROTTLED, &tty->flags)) {
3074                         info->serial_signals |= SerialSignal_RTS;
3075                 }
3076                 spin_lock_irqsave(&info->irq_spinlock,flags);
3077                 usc_set_serial_signals(info);
3078                 spin_unlock_irqrestore(&info->irq_spinlock,flags);
3079         }
3080         
3081         /* Handle turning off CRTSCTS */
3082         if (old_termios->c_cflag & CRTSCTS &&
3083             !(tty->termios->c_cflag & CRTSCTS)) {
3084                 tty->hw_stopped = 0;
3085                 mgsl_start(tty);
3086         }
3087
3088 }       /* end of mgsl_set_termios() */
3089
3090 /* mgsl_close()
3091  * 
3092  *      Called when port is closed. Wait for remaining data to be
3093  *      sent. Disable port and free resources.
3094  *      
3095  * Arguments:
3096  * 
3097  *      tty     pointer to open tty structure
3098  *      filp    pointer to open file object
3099  *      
3100  * Return Value:        None
3101  */
3102 static void mgsl_close(struct tty_struct *tty, struct file * filp)
3103 {
3104         struct mgsl_struct * info = (struct mgsl_struct *)tty->driver_data;
3105
3106         if (mgsl_paranoia_check(info, tty->name, "mgsl_close"))
3107                 return;
3108         
3109         if (debug_level >= DEBUG_LEVEL_INFO)
3110                 printk("%s(%d):mgsl_close(%s) entry, count=%d\n",
3111                          __FILE__,__LINE__, info->device_name, info->count);
3112                          
3113         if (!info->count)
3114                 return;
3115
3116         if (tty_hung_up_p(filp))
3117                 goto cleanup;
3118                         
3119         if ((tty->count == 1) && (info->count != 1)) {
3120                 /*
3121                  * tty->count is 1 and the tty structure will be freed.
3122                  * info->count should be one in this case.
3123                  * if it's not, correct it so that the port is shutdown.
3124                  */
3125                 printk("mgsl_close: bad refcount; tty->count is 1, "
3126                        "info->count is %d\n", info->count);
3127                 info->count = 1;
3128         }
3129         
3130         info->count--;
3131         
3132         /* if at least one open remaining, leave hardware active */
3133         if (info->count)
3134                 goto cleanup;
3135         
3136         info->flags |= ASYNC_CLOSING;
3137         
3138         /* set tty->closing to notify line discipline to 
3139          * only process XON/XOFF characters. Only the N_TTY
3140          * discipline appears to use this (ppp does not).
3141          */
3142         tty->closing = 1;
3143         
3144         /* wait for transmit data to clear all layers */
3145         
3146         if (info->closing_wait != ASYNC_CLOSING_WAIT_NONE) {
3147                 if (debug_level >= DEBUG_LEVEL_INFO)
3148                         printk("%s(%d):mgsl_close(%s) calling tty_wait_until_sent\n",
3149                                  __FILE__,__LINE__, info->device_name );
3150                 tty_wait_until_sent(tty, info->closing_wait);
3151         }
3152                 
3153         if (info->flags & ASYNC_INITIALIZED)
3154                 mgsl_wait_until_sent(tty, info->timeout);
3155
3156         if (tty->driver->flush_buffer)
3157                 tty->driver->flush_buffer(tty);
3158
3159         tty_ldisc_flush(tty);
3160                 
3161         shutdown(info);
3162         
3163         tty->closing = 0;
3164         info->tty = NULL;
3165         
3166         if (info->blocked_open) {
3167                 if (info->close_delay) {
3168                         msleep_interruptible(jiffies_to_msecs(info->close_delay));
3169                 }
3170                 wake_up_interruptible(&info->open_wait);
3171         }
3172         
3173         info->flags &= ~(ASYNC_NORMAL_ACTIVE|ASYNC_CLOSING);
3174                          
3175         wake_up_interruptible(&info->close_wait);
3176         
3177 cleanup:                        
3178         if (debug_level >= DEBUG_LEVEL_INFO)
3179                 printk("%s(%d):mgsl_close(%s) exit, count=%d\n", __FILE__,__LINE__,
3180                         tty->driver->name, info->count);
3181                         
3182 }       /* end of mgsl_close() */
3183
3184 /* mgsl_wait_until_sent()
3185  *
3186  *      Wait until the transmitter is empty.
3187  *
3188  * Arguments:
3189  *
3190  *      tty             pointer to tty info structure
3191  *      timeout         time to wait for send completion
3192  *
3193  * Return Value:        None
3194  */
3195 static void mgsl_wait_until_sent(struct tty_struct *tty, int timeout)
3196 {
3197         struct mgsl_struct * info = (struct mgsl_struct *)tty->driver_data;
3198         unsigned long orig_jiffies, char_time;
3199
3200         if (!info )
3201                 return;
3202
3203         if (debug_level >= DEBUG_LEVEL_INFO)
3204                 printk("%s(%d):mgsl_wait_until_sent(%s) entry\n",
3205                          __FILE__,__LINE__, info->device_name );
3206       
3207         if (mgsl_paranoia_check(info, tty->name, "mgsl_wait_until_sent"))
3208                 return;
3209
3210         if (!(info->flags & ASYNC_INITIALIZED))
3211                 goto exit;
3212          
3213         orig_jiffies = jiffies;
3214       
3215         /* Set check interval to 1/5 of estimated time to
3216          * send a character, and make it at least 1. The check
3217          * interval should also be less than the timeout.
3218          * Note: use tight timings here to satisfy the NIST-PCTS.
3219          */ 
3220        
3221         if ( info->params.data_rate ) {
3222                 char_time = info->timeout/(32 * 5);
3223                 if (!char_time)
3224                         char_time++;
3225         } else
3226                 char_time = 1;
3227                 
3228         if (timeout)
3229                 char_time = min_t(unsigned long, char_time, timeout);
3230                 
3231         if ( info->params.mode == MGSL_MODE_HDLC ||
3232                 info->params.mode == MGSL_MODE_RAW ) {
3233                 while (info->tx_active) {
3234                         msleep_interruptible(jiffies_to_msecs(char_time));
3235                         if (signal_pending(current))
3236                                 break;
3237                         if (timeout && time_after(jiffies, orig_jiffies + timeout))
3238                                 break;
3239                 }
3240         } else {
3241                 while (!(usc_InReg(info,TCSR) & TXSTATUS_ALL_SENT) &&
3242                         info->tx_enabled) {
3243                         msleep_interruptible(jiffies_to_msecs(char_time));
3244                         if (signal_pending(current))
3245                                 break;
3246                         if (timeout && time_after(jiffies, orig_jiffies + timeout))
3247                                 break;
3248                 }
3249         }
3250       
3251 exit:
3252         if (debug_level >= DEBUG_LEVEL_INFO)
3253                 printk("%s(%d):mgsl_wait_until_sent(%s) exit\n",
3254                          __FILE__,__LINE__, info->device_name );
3255                          
3256 }       /* end of mgsl_wait_until_sent() */
3257
3258 /* mgsl_hangup()
3259  *
3260  *      Called by tty_hangup() when a hangup is signaled.
3261  *      This is the same as to closing all open files for the port.
3262  *
3263  * Arguments:           tty     pointer to associated tty object
3264  * Return Value:        None
3265  */
3266 static void mgsl_hangup(struct tty_struct *tty)
3267 {
3268         struct mgsl_struct * info = (struct mgsl_struct *)tty->driver_data;
3269         
3270         if (debug_level >= DEBUG_LEVEL_INFO)
3271                 printk("%s(%d):mgsl_hangup(%s)\n",
3272                          __FILE__,__LINE__, info->device_name );
3273                          
3274         if (mgsl_paranoia_check(info, tty->name, "mgsl_hangup"))
3275                 return;
3276
3277         mgsl_flush_buffer(tty);
3278         shutdown(info);
3279         
3280         info->count = 0;        
3281         info->flags &= ~ASYNC_NORMAL_ACTIVE;
3282         info->tty = NULL;
3283
3284         wake_up_interruptible(&info->open_wait);
3285         
3286 }       /* end of mgsl_hangup() */
3287
3288 /* block_til_ready()
3289  * 
3290  *      Block the current process until the specified port
3291  *      is ready to be opened.
3292  *      
3293  * Arguments:
3294  * 
3295  *      tty             pointer to tty info structure
3296  *      filp            pointer to open file object
3297  *      info            pointer to device instance data
3298  *      
3299  * Return Value:        0 if success, otherwise error code
3300  */
3301 static int block_til_ready(struct tty_struct *tty, struct file * filp,
3302                            struct mgsl_struct *info)
3303 {
3304         DECLARE_WAITQUEUE(wait, current);
3305         int             retval;
3306         int             do_clocal = 0, extra_count = 0;
3307         unsigned long   flags;
3308         
3309         if (debug_level >= DEBUG_LEVEL_INFO)
3310                 printk("%s(%d):block_til_ready on %s\n",
3311                          __FILE__,__LINE__, tty->driver->name );
3312
3313         if (filp->f_flags & O_NONBLOCK || tty->flags & (1 << TTY_IO_ERROR)){
3314                 /* nonblock mode is set or port is not enabled */
3315                 info->flags |= ASYNC_NORMAL_ACTIVE;
3316                 return 0;
3317         }
3318
3319         if (tty->termios->c_cflag & CLOCAL)
3320                 do_clocal = 1;
3321
3322         /* Wait for carrier detect and the line to become
3323          * free (i.e., not in use by the callout).  While we are in
3324          * this loop, info->count is dropped by one, so that
3325          * mgsl_close() knows when to free things.  We restore it upon
3326          * exit, either normal or abnormal.
3327          */
3328          
3329         retval = 0;
3330         add_wait_queue(&info->open_wait, &wait);
3331         
3332         if (debug_level >= DEBUG_LEVEL_INFO)
3333                 printk("%s(%d):block_til_ready before block on %s count=%d\n",
3334                          __FILE__,__LINE__, tty->driver->name, info->count );
3335
3336         spin_lock_irqsave(&info->irq_spinlock, flags);
3337         if (!tty_hung_up_p(filp)) {
3338                 extra_count = 1;
3339                 info->count--;
3340         }
3341         spin_unlock_irqrestore(&info->irq_spinlock, flags);
3342         info->blocked_open++;
3343         
3344         while (1) {
3345                 if (tty->termios->c_cflag & CBAUD) {
3346                         spin_lock_irqsave(&info->irq_spinlock,flags);
3347                         info->serial_signals |= SerialSignal_RTS + SerialSignal_DTR;
3348                         usc_set_serial_signals(info);
3349                         spin_unlock_irqrestore(&info->irq_spinlock,flags);
3350                 }
3351                 
3352                 set_current_state(TASK_INTERRUPTIBLE);
3353                 
3354                 if (tty_hung_up_p(filp) || !(info->flags & ASYNC_INITIALIZED)){
3355                         retval = (info->flags & ASYNC_HUP_NOTIFY) ?
3356                                         -EAGAIN : -ERESTARTSYS;
3357                         break;
3358                 }
3359                 
3360                 spin_lock_irqsave(&info->irq_spinlock,flags);
3361                 usc_get_serial_signals(info);
3362                 spin_unlock_irqrestore(&info->irq_spinlock,flags);
3363                 
3364                 if (!(info->flags & ASYNC_CLOSING) &&
3365                     (do_clocal || (info->serial_signals & SerialSignal_DCD)) ) {
3366                         break;
3367                 }
3368                         
3369                 if (signal_pending(current)) {
3370                         retval = -ERESTARTSYS;
3371                         break;
3372                 }
3373                 
3374                 if (debug_level >= DEBUG_LEVEL_INFO)
3375                         printk("%s(%d):block_til_ready blocking on %s count=%d\n",
3376                                  __FILE__,__LINE__, tty->driver->name, info->count );
3377                                  
3378                 schedule();
3379         }
3380         
3381         set_current_state(TASK_RUNNING);
3382         remove_wait_queue(&info->open_wait, &wait);
3383         
3384         if (extra_count)
3385                 info->count++;
3386         info->blocked_open--;
3387         
3388         if (debug_level >= DEBUG_LEVEL_INFO)
3389                 printk("%s(%d):block_til_ready after blocking on %s count=%d\n",
3390                          __FILE__,__LINE__, tty->driver->name, info->count );
3391                          
3392         if (!retval)
3393                 info->flags |= ASYNC_NORMAL_ACTIVE;
3394                 
3395         return retval;
3396         
3397 }       /* end of block_til_ready() */
3398
3399 /* mgsl_open()
3400  *
3401  *      Called when a port is opened.  Init and enable port.
3402  *      Perform serial-specific initialization for the tty structure.
3403  *
3404  * Arguments:           tty     pointer to tty info structure
3405  *                      filp    associated file pointer
3406  *
3407  * Return Value:        0 if success, otherwise error code
3408  */
3409 static int mgsl_open(struct tty_struct *tty, struct file * filp)
3410 {
3411         struct mgsl_struct      *info;
3412         int                     retval, line;
3413         unsigned long flags;
3414
3415         /* verify range of specified line number */     
3416         line = tty->index;
3417         if ((line < 0) || (line >= mgsl_device_count)) {
3418                 printk("%s(%d):mgsl_open with invalid line #%d.\n",
3419                         __FILE__,__LINE__,line);
3420                 return -ENODEV;
3421         }
3422
3423         /* find the info structure for the specified line */
3424         info = mgsl_device_list;
3425         while(info && info->line != line)
3426                 info = info->next_device;
3427         if (mgsl_paranoia_check(info, tty->name, "mgsl_open"))
3428                 return -ENODEV;
3429         
3430         tty->driver_data = info;
3431         info->tty = tty;
3432                 
3433         if (debug_level >= DEBUG_LEVEL_INFO)
3434                 printk("%s(%d):mgsl_open(%s), old ref count = %d\n",
3435                          __FILE__,__LINE__,tty->driver->name, info->count);
3436
3437         /* If port is closing, signal caller to try again */
3438         if (tty_hung_up_p(filp) || info->flags & ASYNC_CLOSING){
3439                 if (info->flags & ASYNC_CLOSING)
3440                         interruptible_sleep_on(&info->close_wait);
3441                 retval = ((info->flags & ASYNC_HUP_NOTIFY) ?
3442                         -EAGAIN : -ERESTARTSYS);
3443                 goto cleanup;
3444         }
3445         
3446         info->tty->low_latency = (info->flags & ASYNC_LOW_LATENCY) ? 1 : 0;
3447
3448         spin_lock_irqsave(&info->netlock, flags);
3449         if (info->netcount) {
3450                 retval = -EBUSY;
3451                 spin_unlock_irqrestore(&info->netlock, flags);
3452                 goto cleanup;
3453         }
3454         info->count++;
3455         spin_unlock_irqrestore(&info->netlock, flags);
3456
3457         if (info->count == 1) {
3458                 /* 1st open on this device, init hardware */
3459                 retval = startup(info);
3460                 if (retval < 0)
3461                         goto cleanup;
3462         }
3463
3464         retval = block_til_ready(tty, filp, info);
3465         if (retval) {
3466                 if (debug_level >= DEBUG_LEVEL_INFO)
3467                         printk("%s(%d):block_til_ready(%s) returned %d\n",
3468                                  __FILE__,__LINE__, info->device_name, retval);
3469                 goto cleanup;
3470         }
3471
3472         if (debug_level >= DEBUG_LEVEL_INFO)
3473                 printk("%s(%d):mgsl_open(%s) success\n",
3474                          __FILE__,__LINE__, info->device_name);
3475         retval = 0;
3476         
3477 cleanup:                        
3478         if (retval) {
3479                 if (tty->count == 1)
3480                         info->tty = NULL; /* tty layer will release tty struct */
3481                 if(info->count)
3482                         info->count--;
3483         }
3484         
3485         return retval;
3486         
3487 }       /* end of mgsl_open() */
3488
3489 /*
3490  * /proc fs routines....
3491  */
3492
3493 static inline int line_info(char *buf, struct mgsl_struct *info)
3494 {
3495         char    stat_buf[30];
3496         int     ret;
3497         unsigned long flags;
3498
3499         if (info->bus_type == MGSL_BUS_TYPE_PCI) {
3500                 ret = sprintf(buf, "%s:PCI io:%04X irq:%d mem:%08X lcr:%08X",
3501                         info->device_name, info->io_base, info->irq_level,
3502                         info->phys_memory_base, info->phys_lcr_base);
3503         } else {
3504                 ret = sprintf(buf, "%s:(E)ISA io:%04X irq:%d dma:%d",
3505                         info->device_name, info->io_base, 
3506                         info->irq_level, info->dma_level);
3507         }
3508
3509         /* output current serial signal states */
3510         spin_lock_irqsave(&info->irq_spinlock,flags);
3511         usc_get_serial_signals(info);
3512         spin_unlock_irqrestore(&info->irq_spinlock,flags);
3513         
3514         stat_buf[0] = 0;
3515         stat_buf[1] = 0;
3516         if (info->serial_signals & SerialSignal_RTS)
3517                 strcat(stat_buf, "|RTS");
3518         if (info->serial_signals & SerialSignal_CTS)
3519                 strcat(stat_buf, "|CTS");
3520         if (info->serial_signals & SerialSignal_DTR)
3521                 strcat(stat_buf, "|DTR");
3522         if (info->serial_signals & SerialSignal_DSR)
3523                 strcat(stat_buf, "|DSR");
3524         if (info->serial_signals & SerialSignal_DCD)
3525                 strcat(stat_buf, "|CD");
3526         if (info->serial_signals & SerialSignal_RI)
3527                 strcat(stat_buf, "|RI");
3528
3529         if (info->params.mode == MGSL_MODE_HDLC ||
3530             info->params.mode == MGSL_MODE_RAW ) {
3531                 ret += sprintf(buf+ret, " HDLC txok:%d rxok:%d",
3532                               info->icount.txok, info->icount.rxok);
3533                 if (info->icount.txunder)
3534                         ret += sprintf(buf+ret, " txunder:%d", info->icount.txunder);
3535                 if (info->icount.txabort)
3536                         ret += sprintf(buf+ret, " txabort:%d", info->icount.txabort);
3537                 if (info->icount.rxshort)
3538                         ret += sprintf(buf+ret, " rxshort:%d", info->icount.rxshort);   
3539                 if (info->icount.rxlong)
3540                         ret += sprintf(buf+ret, " rxlong:%d", info->icount.rxlong);
3541                 if (info->icount.rxover)
3542                         ret += sprintf(buf+ret, " rxover:%d", info->icount.rxover);
3543                 if (info->icount.rxcrc)
3544                         ret += sprintf(buf+ret, " rxcrc:%d", info->icount.rxcrc);
3545         } else {
3546                 ret += sprintf(buf+ret, " ASYNC tx:%d rx:%d",
3547                               info->icount.tx, info->icount.rx);
3548                 if (info->icount.frame)
3549                         ret += sprintf(buf+ret, " fe:%d", info->icount.frame);
3550                 if (info->icount.parity)
3551                         ret += sprintf(buf+ret, " pe:%d", info->icount.parity);
3552                 if (info->icount.brk)
3553                         ret += sprintf(buf+ret, " brk:%d", info->icount.brk);   
3554                 if (info->icount.overrun)
3555                         ret += sprintf(buf+ret, " oe:%d", info->icount.overrun);
3556         }
3557         
3558         /* Append serial signal status to end */
3559         ret += sprintf(buf+ret, " %s\n", stat_buf+1);
3560         
3561         ret += sprintf(buf+ret, "txactive=%d bh_req=%d bh_run=%d pending_bh=%x\n",
3562          info->tx_active,info->bh_requested,info->bh_running,
3563          info->pending_bh);
3564          
3565         spin_lock_irqsave(&info->irq_spinlock,flags);
3566         {       
3567         u16 Tcsr = usc_InReg( info, TCSR );
3568         u16 Tdmr = usc_InDmaReg( info, TDMR );
3569         u16 Ticr = usc_InReg( info, TICR );
3570         u16 Rscr = usc_InReg( info, RCSR );
3571         u16 Rdmr = usc_InDmaReg( info, RDMR );
3572         u16 Ricr = usc_InReg( info, RICR );
3573         u16 Icr = usc_InReg( info, ICR );
3574         u16 Dccr = usc_InReg( info, DCCR );
3575         u16 Tmr = usc_InReg( info, TMR );
3576         u16 Tccr = usc_InReg( info, TCCR );
3577         u16 Ccar = inw( info->io_base + CCAR );
3578         ret += sprintf(buf+ret, "tcsr=%04X tdmr=%04X ticr=%04X rcsr=%04X rdmr=%04X\n"
3579                         "ricr=%04X icr =%04X dccr=%04X tmr=%04X tccr=%04X ccar=%04X\n",
3580                         Tcsr,Tdmr,Ticr,Rscr,Rdmr,Ricr,Icr,Dccr,Tmr,Tccr,Ccar );
3581         }
3582         spin_unlock_irqrestore(&info->irq_spinlock,flags);
3583         
3584         return ret;
3585         
3586 }       /* end of line_info() */
3587
3588 /* mgsl_read_proc()
3589  * 
3590  * Called to print information about devices
3591  * 
3592  * Arguments:
3593  *      page    page of memory to hold returned info
3594  *      start   
3595  *      off
3596  *      count
3597  *      eof
3598  *      data
3599  *      
3600  * Return Value:
3601  */
3602 static int mgsl_read_proc(char *page, char **start, off_t off, int count,
3603                  int *eof, void *data)
3604 {
3605         int len = 0, l;
3606         off_t   begin = 0;
3607         struct mgsl_struct *info;
3608         
3609         len += sprintf(page, "synclink driver:%s\n", driver_version);
3610         
3611         info = mgsl_device_list;
3612         while( info ) {
3613                 l = line_info(page + len, info);
3614                 len += l;
3615                 if (len+begin > off+count)
3616                         goto done;
3617                 if (len+begin < off) {
3618                         begin += len;
3619                         len = 0;
3620                 }
3621                 info = info->next_device;
3622         }
3623
3624         *eof = 1;
3625 done:
3626         if (off >= len+begin)
3627                 return 0;
3628         *start = page + (off-begin);
3629         return ((count < begin+len-off) ? count : begin+len-off);
3630         
3631 }       /* end of mgsl_read_proc() */
3632
3633 /* mgsl_allocate_dma_buffers()
3634  * 
3635  *      Allocate and format DMA buffers (ISA adapter)
3636  *      or format shared memory buffers (PCI adapter).
3637  * 
3638  * Arguments:           info    pointer to device instance data
3639  * Return Value:        0 if success, otherwise error
3640  */
3641 static int mgsl_allocate_dma_buffers(struct mgsl_struct *info)
3642 {
3643         unsigned short BuffersPerFrame;