drivers/usb/serial/cypress_m8.c

   1 /*
   2  * USB Cypress M8 driver
   3  *
   4  *      Copyright (C) 2004
   5  *          Lonnie Mendez (dignome@gmail.com)
   6  *      Copyright (C) 2003,2004
   7  *          Neil Whelchel (koyama@firstlight.net)
   8  *
   9  *      This program is free software; you can redistribute it and/or modify
  10  *      it under the terms of the GNU General Public License as published by
  11  *      the Free Software Foundation; either version 2 of the License, or
  12  *      (at your option) any later version.
  13  *
  14  * See Documentation/usb/usb-serial.txt for more information on using this driver
  15  *
  16  * See http://geocities.com/i0xox0i for information on this driver and the
  17  * earthmate usb device.
  18  *
  19  *  Lonnie Mendez <dignome@gmail.com>
  20  *  4-29-2005
  21  *      Fixed problem where setting or retreiving the serial config would fail with
  22  *      EPIPE.  Removed CRTS toggling so the driver behaves more like other usbserial
  23  *      adapters.  Issued new interval of 1ms instead of the default 10ms.  As a
  24  *      result, transfer speed has been substantially increased.  From avg. 850bps to
  25  *      avg. 3300bps.  initial termios has also been modified.  Cleaned up code and
  26  *      formatting issues so it is more readable.  Replaced the C++ style comments.
  27  *
  28  *  Lonnie Mendez <dignome@gmail.com>
  29  *  12-15-2004
  30  *      Incorporated write buffering from pl2303 driver.  Fixed bug with line
  31  *      handling so both lines are raised in cypress_open. (was dropping rts)
  32  *      Various code cleanups made as well along with other misc bug fixes.
  33  *
  34  *  Lonnie Mendez <dignome@gmail.com>
  35  *  04-10-2004
  36  *      Driver modified to support dynamic line settings.  Various improvments
  37  *      and features.
  38  *
  39  *  Neil Whelchel
  40  *  10-2003
  41  *      Driver first released.
  42  *
  43  */
  44
  45 /* Thanks to Neil Whelchel for writing the first cypress m8 implementation for linux. */
  46 /* Thanks to cypress for providing references for the hid reports. */
  47 /* Thanks to Jiang Zhang for providing links and for general help. */
  48 /* Code originates and was built up from ftdi_sio, belkin, pl2303 and others. */
  49
  50
  51 #include <linux/kernel.h>
  52 #include <linux/errno.h>
  53 #include <linux/init.h>
  54 #include <linux/slab.h>
  55 #include <linux/tty.h>
  56 #include <linux/tty_driver.h>
  57 #include <linux/tty_flip.h>
  58 #include <linux/module.h>
  59 #include <linux/moduleparam.h>
  60 #include <linux/spinlock.h>
  61 #include <linux/usb.h>
  62 #include <linux/usb/serial.h>
  63 #include <linux/serial.h>
  64 #include <linux/delay.h>
  65 #include <asm/uaccess.h>
  66
  67 #include "cypress_m8.h"
  68
  69
  70 #ifdef CONFIG_USB_SERIAL_DEBUG
  71         static int debug = 1;
  72 #else
  73         static int debug;
  74 #endif
  75 static int stats;
  76 static int interval;
  77
  78 /*
  79  * Version Information
  80  */
  81 #define DRIVER_VERSION "v1.09"
  82 #define DRIVER_AUTHOR "Lonnie Mendez <dignome@gmail.com>, Neil Whelchel <koyama@firstlight.net>"
  83 #define DRIVER_DESC "Cypress USB to Serial Driver"
  84
  85 /* write buffer size defines */
  86 #define CYPRESS_BUF_SIZE        1024
  87 #define CYPRESS_CLOSING_WAIT    (30*HZ)
  88
  89 static struct usb_device_id id_table_earthmate [] = {
  90         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
  91         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
  92         { }                                             /* Terminating entry */
  93 };
  94
  95 static struct usb_device_id id_table_cyphidcomrs232 [] = {
  96         { USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
  97         { USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
  98         { }                                             /* Terminating entry */
  99 };
 100
 101 static struct usb_device_id id_table_nokiaca42v2 [] = {
 102         { USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
 103         { }                                             /* Terminating entry */
 104 };
 105
 106 static struct usb_device_id id_table_combined [] = {
 107         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB) },
 108         { USB_DEVICE(VENDOR_ID_DELORME, PRODUCT_ID_EARTHMATEUSB_LT20) },
 109         { USB_DEVICE(VENDOR_ID_CYPRESS, PRODUCT_ID_CYPHIDCOM) },
 110         { USB_DEVICE(VENDOR_ID_POWERCOM, PRODUCT_ID_UPS) },
 111         { USB_DEVICE(VENDOR_ID_DAZZLE, PRODUCT_ID_CA42) },
 112         { }                                             /* Terminating entry */
 113 };
 114
 115 MODULE_DEVICE_TABLE (usb, id_table_combined);
 116
 117 static struct usb_driver cypress_driver = {
 118         .name =         "cypress",
 119         .probe =        usb_serial_probe,
 120         .disconnect =   usb_serial_disconnect,
 121         .id_table =     id_table_combined,
 122         .no_dynamic_id =        1,
 123 };
 124
 125 enum packet_format {
 126         packet_format_1,  /* b0:status, b1:payload count */
 127         packet_format_2   /* b0[7:3]:status, b0[2:0]:payload count */
 128 };
 129
 130 struct cypress_private {
 131         spinlock_t lock;                   /* private lock */
 132         int chiptype;                      /* identifier of device, for quirks/etc */
 133         int bytes_in;                      /* used for statistics */
 134         int bytes_out;                     /* used for statistics */
 135         int cmd_count;                     /* used for statistics */
 136         int cmd_ctrl;                      /* always set this to 1 before issuing a command */
 137         struct cypress_buf *buf;           /* write buffer */
 138         int write_urb_in_use;              /* write urb in use indicator */
 139         int write_urb_interval;            /* interval to use for write urb */
 140         int read_urb_interval;             /* interval to use for read urb */
 141         int comm_is_ok;                    /* true if communication is (still) ok */
 142         int termios_initialized;
 143         __u8 line_control;                 /* holds dtr / rts value */
 144         __u8 current_status;               /* received from last read - info on dsr,cts,cd,ri,etc */
 145         __u8 current_config;               /* stores the current configuration byte */
 146         __u8 rx_flags;                     /* throttling - used from whiteheat/ftdi_sio */
 147         enum packet_format pkt_fmt;        /* format to use for packet send / receive */
 148         int get_cfg_unsafe;                /* If true, the CYPRESS_GET_CONFIG is unsafe */
 149         int baud_rate;                     /* stores current baud rate in integer form */
 150         int isthrottled;                   /* if throttled, discard reads */
 151         wait_queue_head_t delta_msr_wait;  /* used for TIOCMIWAIT */
 152         char prev_status, diff_status;     /* used for TIOCMIWAIT */
 153         /* we pass a pointer to this as the arguement sent to cypress_set_termios old_termios */
 154         struct ktermios tmp_termios;       /* stores the old termios settings */
 155 };
 156
 157 /* write buffer structure */
 158 struct cypress_buf {
 159         unsigned int    buf_size;
 160         char            *buf_buf;
 161         char            *buf_get;
 162         char            *buf_put;
 163 };
 164
 165 /* function prototypes for the Cypress USB to serial device */
 166 static int  cypress_earthmate_startup   (struct usb_serial *serial);
 167 static int  cypress_hidcom_startup      (struct usb_serial *serial);
 168 static int  cypress_ca42v2_startup      (struct usb_serial *serial);
 169 static void cypress_shutdown            (struct usb_serial *serial);
 170 static int  cypress_open                (struct usb_serial_port *port, struct file *filp);
 171 static void cypress_close               (struct usb_serial_port *port, struct file *filp);
 172 static int  cypress_write               (struct usb_serial_port *port, const unsigned char *buf, int count);
 173 static void cypress_send                (struct usb_serial_port *port);
 174 static int  cypress_write_room          (struct usb_serial_port *port);
 175 static int  cypress_ioctl               (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg);
 176 static void cypress_set_termios         (struct usb_serial_port *port, struct ktermios * old);
 177 static int  cypress_tiocmget            (struct usb_serial_port *port, struct file *file);
 178 static int  cypress_tiocmset            (struct usb_serial_port *port, struct file *file, unsigned int set, unsigned int clear);
 179 static int  cypress_chars_in_buffer     (struct usb_serial_port *port);
 180 static void cypress_throttle            (struct usb_serial_port *port);
 181 static void cypress_unthrottle          (struct usb_serial_port *port);
 182 static void cypress_set_dead            (struct usb_serial_port *port);
 183 static void cypress_read_int_callback   (struct urb *urb);
 184 static void cypress_write_int_callback  (struct urb *urb);
 185 /* write buffer functions */
 186 static struct cypress_buf *cypress_buf_alloc(unsigned int size);
 187 static void               cypress_buf_free(struct cypress_buf *cb);
 188 static void               cypress_buf_clear(struct cypress_buf *cb);
 189 static unsigned int       cypress_buf_data_avail(struct cypress_buf *cb);
 190 static unsigned int       cypress_buf_space_avail(struct cypress_buf *cb);
 191 static unsigned int       cypress_buf_put(struct cypress_buf *cb, const char *buf, unsigned int count);
 192 static unsigned int       cypress_buf_get(struct cypress_buf *cb, char *buf, unsigned int count);
 193
 194
 195 static struct usb_serial_driver cypress_earthmate_device = {
 196         .driver = {
 197                 .owner =                THIS_MODULE,
 198                 .name =                 "earthmate",
 199         },
 200         .description =                  "DeLorme Earthmate USB",
 201         .usb_driver =                   &cypress_driver,
 202         .id_table =                     id_table_earthmate,
 203         .num_ports =                    1,
 204         .attach =                       cypress_earthmate_startup,
 205         .shutdown =                     cypress_shutdown,
 206         .open =                         cypress_open,
 207         .close =                        cypress_close,
 208         .write =                        cypress_write,
 209         .write_room =                   cypress_write_room,
 210         .ioctl =                        cypress_ioctl,
 211         .set_termios =                  cypress_set_termios,
 212         .tiocmget =                     cypress_tiocmget,
 213         .tiocmset =                     cypress_tiocmset,
 214         .chars_in_buffer =              cypress_chars_in_buffer,
 215         .throttle =                     cypress_throttle,
 216         .unthrottle =                   cypress_unthrottle,
 217         .read_int_callback =            cypress_read_int_callback,
 218         .write_int_callback =           cypress_write_int_callback,
 219 };
 220
 221 static struct usb_serial_driver cypress_hidcom_device = {
 222         .driver = {
 223                 .owner =                THIS_MODULE,
 224                 .name =                 "cyphidcom",
 225         },
 226         .description =                  "HID->COM RS232 Adapter",
 227         .usb_driver =                   &cypress_driver,
 228         .id_table =                     id_table_cyphidcomrs232,
 229         .num_ports =                    1,
 230         .attach =                       cypress_hidcom_startup,
 231         .shutdown =                     cypress_shutdown,
 232         .open =                         cypress_open,
 233         .close =                        cypress_close,
 234         .write =                        cypress_write,
 235         .write_room =                   cypress_write_room,
 236         .ioctl =                        cypress_ioctl,
 237         .set_termios =                  cypress_set_termios,
 238         .tiocmget =                     cypress_tiocmget,
 239         .tiocmset =                     cypress_tiocmset,
 240         .chars_in_buffer =              cypress_chars_in_buffer,
 241         .throttle =                     cypress_throttle,
 242         .unthrottle =                   cypress_unthrottle,
 243         .read_int_callback =            cypress_read_int_callback,
 244         .write_int_callback =           cypress_write_int_callback,
 245 };
 246
 247 static struct usb_serial_driver cypress_ca42v2_device = {
 248         .driver = {
 249                 .owner =                THIS_MODULE,
 250                 .name =                 "nokiaca42v2",
 251         },
 252         .description =                  "Nokia CA-42 V2 Adapter",
 253         .usb_driver =                   &cypress_driver,
 254         .id_table =                     id_table_nokiaca42v2,
 255         .num_ports =                    1,
 256         .attach =                       cypress_ca42v2_startup,
 257         .shutdown =                     cypress_shutdown,
 258         .open =                         cypress_open,
 259         .close =                        cypress_close,
 260         .write =                        cypress_write,
 261         .write_room =                   cypress_write_room,
 262         .ioctl =                        cypress_ioctl,
 263         .set_termios =                  cypress_set_termios,
 264         .tiocmget =                     cypress_tiocmget,
 265         .tiocmset =                     cypress_tiocmset,
 266         .chars_in_buffer =              cypress_chars_in_buffer,
 267         .throttle =                     cypress_throttle,
 268         .unthrottle =                   cypress_unthrottle,
 269         .read_int_callback =            cypress_read_int_callback,
 270         .write_int_callback =           cypress_write_int_callback,
 271 };
 272
 273 /*****************************************************************************
 274  * Cypress serial helper functions
 275  *****************************************************************************/
 276
 277
 278 static int analyze_baud_rate(struct usb_serial_port *port, speed_t new_rate)
 279 {
 280         struct cypress_private *priv;
 281         priv = usb_get_serial_port_data(port);
 282
 283         /*
 284          * The general purpose firmware for the Cypress M8 allows for
 285          * a maximum speed of 57600bps (I have no idea whether DeLorme
 286          * chose to use the general purpose firmware or not), if you
 287          * need to modify this speed setting for your own project
 288          * please add your own chiptype and modify the code likewise.
 289          * The Cypress HID->COM device will work successfully up to
 290          * 115200bps (but the actual throughput is around 3kBps).
 291          */
 292         if (port->serial->dev->speed == USB_SPEED_LOW) {
 293                 /*
 294                  * Mike Isely <isely@pobox.com> 2-Feb-2008: The
 295                  * Cypress app note that describes this mechanism
 296                  * states the the low-speed part can't handle more
 297                  * than 800 bytes/sec, in which case 4800 baud is the
 298                  * safest speed for a part like that.
 299                  */
 300                 if (new_rate > 4800) {
 301                         dbg("%s - failed setting baud rate, device incapable "
 302                             "speed %d", __func__, new_rate);
 303                         return -1;
 304                 }
 305         }
 306         switch (priv->chiptype) {
 307         case CT_EARTHMATE:
 308                 if (new_rate <= 600) {
 309                         /* 300 and 600 baud rates are supported under
 310                          * the generic firmware, but are not used with
 311                          * NMEA and SiRF protocols */
 312                         dbg("%s - failed setting baud rate, unsupported speed "
 313                             "of %d on Earthmate GPS", __func__, new_rate);
 314                         return -1;
 315                 }
 316                 break;
 317         default:
 318                 break;
 319         }
 320         return new_rate;
 321 }
 322
 323
 324 /* This function can either set or retrieve the current serial line settings */
 325 static int cypress_serial_control (struct usb_serial_port *port, speed_t baud_rate, int data_bits, int stop_bits,
 326                                    int parity_enable, int parity_type, int reset, int cypress_request_type)
 327 {
 328         int new_baudrate = 0, retval = 0, tries = 0;
 329         struct cypress_private *priv;
 330         __u8 feature_buffer[5];
 331         unsigned long flags;
 332
 333         dbg("%s", __func__);
 334
 335         priv = usb_get_serial_port_data(port);
 336
 337         if (!priv->comm_is_ok)
 338                 return -ENODEV;
 339
 340         switch(cypress_request_type) {
 341                 case CYPRESS_SET_CONFIG:
 342                         new_baudrate = priv->baud_rate;
 343                         /* 0 means 'Hang up' so doesn't change the true bit rate */
 344                         if (baud_rate == 0)
 345                                 new_baudrate = priv->baud_rate;
 346                         /* Change of speed ? */
 347                         else if (baud_rate != priv->baud_rate) {
 348                                 dbg("%s - baud rate is changing", __func__);
 349                                 retval = analyze_baud_rate(port, baud_rate);
 350                                 if (retval >=  0) {
 351                                         new_baudrate = retval;
 352                                         dbg("%s - New baud rate set to %d",
 353                                             __func__, new_baudrate);
 354                                 }
 355                         }
 356                         dbg("%s - baud rate is being sent as %d", __func__, new_baudrate);
 357
 358                         memset(feature_buffer, 0, sizeof(feature_buffer));
 359                         /* fill the feature_buffer with new configuration */
 360                         *((u_int32_t *)feature_buffer) = new_baudrate;
 361
 362                         feature_buffer[4] |= data_bits;   /* assign data bits in 2 bit space ( max 3 ) */
 363                         /* 1 bit gap */
 364                         feature_buffer[4] |= (stop_bits << 3);   /* assign stop bits in 1 bit space */
 365                         feature_buffer[4] |= (parity_enable << 4);   /* assign parity flag in 1 bit space */
 366                         feature_buffer[4] |= (parity_type << 5);   /* assign parity type in 1 bit space */
 367                         /* 1 bit gap */
 368                         feature_buffer[4] |= (reset << 7);   /* assign reset at end of byte, 1 bit space */
 369
 370                         dbg("%s - device is being sent this feature report:", __func__);
 371                         dbg("%s - %02X - %02X - %02X - %02X - %02X", __func__, feature_buffer[0], feature_buffer[1],
 372                             feature_buffer[2], feature_buffer[3], feature_buffer[4]);
 373
 374                         do {
 375                                 retval = usb_control_msg(port->serial->dev,
 376                                                 usb_sndctrlpipe(port->serial->dev, 0),
 377                                                 HID_REQ_SET_REPORT,
 378                                                 USB_DIR_OUT | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
 379                                                 0x0300, 0, feature_buffer,
 380                                                 sizeof(feature_buffer), 500);
 381
 382                                 if (tries++ >= 3)
 383                                         break;
 384
 385                         } while (retval != sizeof(feature_buffer) &&
 386                                  retval != -ENODEV);
 387
 388                         if (retval != sizeof(feature_buffer)) {
 389                                 err("%s - failed sending serial line settings - %d", __func__, retval);
 390                                 cypress_set_dead(port);
 391                         } else {
 392                                 spin_lock_irqsave(&priv->lock, flags);
 393                                 priv->baud_rate = new_baudrate;
 394                                 priv->current_config = feature_buffer[4];
 395                                 spin_unlock_irqrestore(&priv->lock, flags);
 396                                 /* If we asked for a speed change encode it */
 397                                 if (baud_rate)
 398                                         tty_encode_baud_rate(port->tty,
 399                                                         new_baudrate, new_baudrate);
 400                         }
 401                 break;
 402                 case CYPRESS_GET_CONFIG:
 403                         if (priv->get_cfg_unsafe) {
 404                                 /* Not implemented for this device,
 405                                    and if we try to do it we're likely
 406                                    to crash the hardware. */
 407                                 return -ENOTTY;
 408                         }
 409                         dbg("%s - retreiving serial line settings", __func__);
 410                         /* set initial values in feature buffer */
 411                         memset(feature_buffer, 0, sizeof(feature_buffer));
 412
 413                         do {
 414                                 retval = usb_control_msg(port->serial->dev,
 415                                                 usb_rcvctrlpipe(port->serial->dev, 0),
 416                                                 HID_REQ_GET_REPORT,
 417                                                 USB_DIR_IN | USB_RECIP_INTERFACE | USB_TYPE_CLASS,
 418                                                 0x0300, 0, feature_buffer,
 419                                                 sizeof(feature_buffer), 500);
 420
 421                                 if (tries++ >= 3)
 422                                         break;
 423
 424                         } while (retval != sizeof(feature_buffer) &&
 425                                  retval != -ENODEV);
 426
 427                         if (retval != sizeof(feature_buffer)) {
 428                                 err("%s - failed to retrieve serial line settings - %d", __func__, retval);
 429                                 cypress_set_dead(port);
 430                                 return retval;
 431                         } else {
 432                                 spin_lock_irqsave(&priv->lock, flags);
 433
 434                                 /* store the config in one byte, and later use bit masks to check values */
 435                                 priv->current_config = feature_buffer[4];
 436                                 priv->baud_rate = *((u_int32_t *)feature_buffer);
 437                                 spin_unlock_irqrestore(&priv->lock, flags);
 438                         }
 439         }
 440         spin_lock_irqsave(&priv->lock, flags);
 441         ++priv->cmd_count;
 442         spin_unlock_irqrestore(&priv->lock, flags);
 443
 444         return retval;
 445 } /* cypress_serial_control */
 446
 447
 448 static void cypress_set_dead(struct usb_serial_port *port)
 449 {
 450         struct cypress_private *priv = usb_get_serial_port_data(port);
 451         unsigned long flags;
 452
 453         spin_lock_irqsave(&priv->lock, flags);
 454         if (!priv->comm_is_ok) {
 455                 spin_unlock_irqrestore(&priv->lock, flags);
 456                 return;
 457         }
 458         priv->comm_is_ok = 0;
 459         spin_unlock_irqrestore(&priv->lock, flags);
 460
 461         err("cypress_m8 suspending failing port %d - interval might be too short",
 462             port->number);
 463 }
 464
 465
 466 /*****************************************************************************
 467  * Cypress serial driver functions
 468  *****************************************************************************/
 469
 470
 471 static int generic_startup (struct usb_serial *serial)
 472 {
 473         struct cypress_private *priv;
 474         struct usb_serial_port *port = serial->port[0];
 475
 476         dbg("%s - port %d", __func__, port->number);
 477
 478         priv = kzalloc(sizeof (struct cypress_private), GFP_KERNEL);
 479         if (!priv)
 480                 return -ENOMEM;
 481
 482         priv->comm_is_ok = !0;
 483         spin_lock_init(&priv->lock);
 484         priv->buf = cypress_buf_alloc(CYPRESS_BUF_SIZE);
 485         if (priv->buf == NULL) {
 486                 kfree(priv);
 487                 return -ENOMEM;
 488         }
 489         init_waitqueue_head(&priv->delta_msr_wait);
 490
 491         usb_reset_configuration (serial->dev);
 492
 493         priv->cmd_ctrl = 0;
 494         priv->line_control = 0;
 495         priv->termios_initialized = 0;
 496         priv->rx_flags = 0;
 497         /* Default packet format setting is determined by packet size.
 498            Anything with a size larger then 9 must have a separate
 499            count field since the 3 bit count field is otherwise too
 500            small.  Otherwise we can use the slightly more compact
 501            format.  This is in accordance with the cypress_m8 serial
 502            converter app note. */
 503         if (port->interrupt_out_size > 9) {
 504                 priv->pkt_fmt = packet_format_1;
 505         } else {
 506                 priv->pkt_fmt = packet_format_2;
 507         }
 508         if (interval > 0) {
 509                 priv->write_urb_interval = interval;
 510                 priv->read_urb_interval = interval;
 511                 dbg("%s - port %d read & write intervals forced to %d",
 512                     __func__,port->number,interval);
 513         } else {
 514                 priv->write_urb_interval = port->interrupt_out_urb->interval;
 515                 priv->read_urb_interval = port->interrupt_in_urb->interval;
 516                 dbg("%s - port %d intervals: read=%d write=%d",
 517                     __func__,port->number,
 518                     priv->read_urb_interval,priv->write_urb_interval);
 519         }
 520         usb_set_serial_port_data(port, priv);
 521
 522         return 0;
 523 }
 524
 525
 526 static int cypress_earthmate_startup (struct usb_serial *serial)
 527 {
 528         struct cypress_private *priv;
 529         struct usb_serial_port *port = serial->port[0];
 530
 531         dbg("%s", __func__);
 532
 533         if (generic_startup(serial)) {
 534                 dbg("%s - Failed setting up port %d", __func__,
 535                                 port->number);
 536                 return 1;
 537         }
 538
 539         priv = usb_get_serial_port_data(port);
 540         priv->chiptype = CT_EARTHMATE;
 541         /* All Earthmate devices use the separated-count packet
 542            format!  Idiotic. */
 543         priv->pkt_fmt = packet_format_1;
 544         if (serial->dev->descriptor.idProduct != cpu_to_le16(PRODUCT_ID_EARTHMATEUSB)) {
 545                 /* The old original USB Earthmate seemed able to
 546                    handle GET_CONFIG requests; everything they've
 547                    produced since that time crashes if this command is
 548                    attempted :-( */
 549                 dbg("%s - Marking this device as unsafe for GET_CONFIG "
 550                     "commands", __func__);
 551                 priv->get_cfg_unsafe = !0;
 552         }
 553
 554         return 0;
 555 } /* cypress_earthmate_startup */
 556
 557
 558 static int cypress_hidcom_startup (struct usb_serial *serial)
 559 {
 560         struct cypress_private *priv;
 561
 562         dbg("%s", __func__);
 563
 564         if (generic_startup(serial)) {
 565                 dbg("%s - Failed setting up port %d", __func__,
 566                                 serial->port[0]->number);
 567                 return 1;
 568         }
 569
 570         priv = usb_get_serial_port_data(serial->port[0]);
 571         priv->chiptype = CT_CYPHIDCOM;
 572
 573         return 0;
 574 } /* cypress_hidcom_startup */
 575
 576
 577 static int cypress_ca42v2_startup (struct usb_serial *serial)
 578 {
 579         struct cypress_private *priv;
 580
 581         dbg("%s", __func__);
 582
 583         if (generic_startup(serial)) {
 584                 dbg("%s - Failed setting up port %d", __func__,
 585                                 serial->port[0]->number);
 586                 return 1;
 587         }
 588
 589         priv = usb_get_serial_port_data(serial->port[0]);
 590         priv->chiptype = CT_CA42V2;
 591
 592         return 0;
 593 } /* cypress_ca42v2_startup */
 594
 595
 596 static void cypress_shutdown (struct usb_serial *serial)
 597 {
 598         struct cypress_private *priv;
 599
 600         dbg ("%s - port %d", __func__, serial->port[0]->number);
 601
 602         /* all open ports are closed at this point */
 603
 604         priv = usb_get_serial_port_data(serial->port[0]);
 605
 606         if (priv) {
 607                 cypress_buf_free(priv->buf);
 608                 kfree(priv);
 609                 usb_set_serial_port_data(serial->port[0], NULL);
 610         }
 611 }
 612
 613
 614 static int cypress_open (struct usb_serial_port *port, struct file *filp)
 615 {
 616         struct cypress_private *priv = usb_get_serial_port_data(port);
 617         struct usb_serial *serial = port->serial;
 618         unsigned long flags;
 619         int result = 0;
 620
 621         dbg("%s - port %d", __func__, port->number);
 622
 623         if (!priv->comm_is_ok)
 624                 return -EIO;
 625
 626         /* clear halts before open */
 627         usb_clear_halt(serial->dev, 0x81);
 628         usb_clear_halt(serial->dev, 0x02);
 629
 630         spin_lock_irqsave(&priv->lock, flags);
 631         /* reset read/write statistics */
 632         priv->bytes_in = 0;
 633         priv->bytes_out = 0;
 634         priv->cmd_count = 0;
 635         priv->rx_flags = 0;
 636         spin_unlock_irqrestore(&priv->lock, flags);
 637
 638         /* setting to zero could cause data loss */
 639         port->tty->low_latency = 1;
 640
 641         /* raise both lines and set termios */
 642         spin_lock_irqsave(&priv->lock, flags);
 643         priv->line_control = CONTROL_DTR | CONTROL_RTS;
 644         priv->cmd_ctrl = 1;
 645         spin_unlock_irqrestore(&priv->lock, flags);
 646         result = cypress_write(port, NULL, 0);
 647
 648         if (result) {
 649                 dev_err(&port->dev, "%s - failed setting the control lines - error %d\n", __func__, result);
 650                 return result;
 651         } else
 652                 dbg("%s - success setting the control lines", __func__);
 653
 654         cypress_set_termios(port, &priv->tmp_termios);
 655
 656         /* setup the port and start reading from the device */
 657         if(!port->interrupt_in_urb){
 658                 err("%s - interrupt_in_urb is empty!", __func__);
 659                 return(-1);
 660         }
 661
 662         usb_fill_int_urb(port->interrupt_in_urb, serial->dev,
 663                 usb_rcvintpipe(serial->dev, port->interrupt_in_endpointAddress),
 664                 port->interrupt_in_urb->transfer_buffer, port->interrupt_in_urb->transfer_buffer_length,
 665                 cypress_read_int_callback, port, priv->read_urb_interval);
 666         result = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL);
 667
 668         if (result){
 669                 dev_err(&port->dev, "%s - failed submitting read urb, error %d\n", __func__, result);
 670                 cypress_set_dead(port);
 671         }
 672
 673         return result;
 674 } /* cypress_open */
 675
 676
 677 static void cypress_close(struct usb_serial_port *port, struct file * filp)
 678 {
 679         struct cypress_private *priv = usb_get_serial_port_data(port);
 680         unsigned int c_cflag;
 681         int bps;
 682         long timeout;
 683         wait_queue_t wait;
 684
 685         dbg("%s - port %d", __func__, port->number);
 686
 687         /* wait for data to drain from buffer */
 688         spin_lock_irq(&priv->lock);
 689         timeout = CYPRESS_CLOSING_WAIT;
 690         init_waitqueue_entry(&wait, current);
 691         add_wait_queue(&port->tty->write_wait, &wait);
 692         for (;;) {
 693                 set_current_state(TASK_INTERRUPTIBLE);
 694                 if (cypress_buf_data_avail(priv->buf) == 0
 695                 || timeout == 0 || signal_pending(current)
 696                 /* without mutex, allowed due to harmless failure mode */
 697                 || port->serial->disconnected)
 698                         break;
 699                 spin_unlock_irq(&priv->lock);
 700                 timeout = schedule_timeout(timeout);
 701                 spin_lock_irq(&priv->lock);
 702         }
 703         set_current_state(TASK_RUNNING);
 704         remove_wait_queue(&port->tty->write_wait, &wait);
 705         /* clear out any remaining data in the buffer */
 706         cypress_buf_clear(priv->buf);
 707         spin_unlock_irq(&priv->lock);
 708
 709         /* writing is potentially harmful, lock must be taken */
 710         mutex_lock(&port->serial->disc_mutex);
 711         if (port->serial->disconnected) {
 712                 mutex_unlock(&port->serial->disc_mutex);
 713                 return;
 714         }
 715         /* wait for characters to drain from device */
 716         bps = tty_get_baud_rate(port->tty);
 717         if (bps > 1200)
 718                 timeout = max((HZ*2560)/bps,HZ/10);
 719         else
 720                 timeout = 2*HZ;
 721         schedule_timeout_interruptible(timeout);
 722
 723         dbg("%s - stopping urbs", __func__);
 724         usb_kill_urb (port->interrupt_in_urb);
 725         usb_kill_urb (port->interrupt_out_urb);
 726
 727         if (port->tty) {
 728                 c_cflag = port->tty->termios->c_cflag;
 729                 if (c_cflag & HUPCL) {
 730                         /* drop dtr and rts */
 731                         priv = usb_get_serial_port_data(port);
 732                         spin_lock_irq(&priv->lock);
 733                         priv->line_control = 0;
 734                         priv->cmd_ctrl = 1;
 735                         spin_unlock_irq(&priv->lock);
 736                         cypress_write(port, NULL, 0);
 737                 }
 738         }
 739
 740         if (stats)
 741                 dev_info (&port->dev, "Statistics: %d Bytes In | %d Bytes Out | %d Commands Issued\n",
 742                           priv->bytes_in, priv->bytes_out, priv->cmd_count);
 743         mutex_unlock(&port->serial->disc_mutex);
 744 } /* cypress_close */
 745
 746
 747 static int cypress_write(struct usb_serial_port *port, const unsigned char *buf, int count)
 748 {
 749         struct cypress_private *priv = usb_get_serial_port_data(port);
 750         unsigned long flags;
 751
 752         dbg("%s - port %d, %d bytes", __func__, port->number, count);
 753
 754         /* line control commands, which need to be executed immediately,
 755            are not put into the buffer for obvious reasons.
 756          */
 757         if (priv->cmd_ctrl) {
 758                 count = 0;
 759                 goto finish;
 760         }
 761
 762         if (!count)
 763                 return count;
 764
 765         spin_lock_irqsave(&priv->lock, flags);
 766         count = cypress_buf_put(priv->buf, buf, count);
 767         spin_unlock_irqrestore(&priv->lock, flags);
 768
 769 finish:
 770         cypress_send(port);
 771
 772         return count;
 773 } /* cypress_write */
 774
 775
 776 static void cypress_send(struct usb_serial_port *port)
 777 {
 778         int count = 0, result, offset, actual_size;
 779         struct cypress_private *priv = usb_get_serial_port_data(port);
 780         unsigned long flags;
 781
 782         if (!priv->comm_is_ok)
 783                 return;
 784
 785         dbg("%s - port %d", __func__, port->number);
 786         dbg("%s - interrupt out size is %d", __func__, port->interrupt_out_size);
 787
 788         spin_lock_irqsave(&priv->lock, flags);
 789         if (priv->write_urb_in_use) {
 790                 dbg("%s - can't write, urb in use", __func__);
 791                 spin_unlock_irqrestore(&priv->lock, flags);
 792                 return;
 793         }
 794         spin_unlock_irqrestore(&priv->lock, flags);
 795
 796         /* clear buffer */
 797         memset(port->interrupt_out_urb->transfer_buffer, 0, port->interrupt_out_size);
 798
 799         spin_lock_irqsave(&priv->lock, flags);
 800         switch (priv->pkt_fmt) {
 801         default:
 802         case packet_format_1:
 803                 /* this is for the CY7C64013... */
 804                 offset = 2;
 805                 port->interrupt_out_buffer[0] = priv->line_control;
 806                 break;
 807         case packet_format_2:
 808                 /* this is for the CY7C63743... */
 809                 offset = 1;
 810                 port->interrupt_out_buffer[0] = priv->line_control;
 811                 break;
 812         }
 813
 814         if (priv->line_control & CONTROL_RESET)
 815                 priv->line_control &= ~CONTROL_RESET;
 816
 817         if (priv->cmd_ctrl) {
 818                 priv->cmd_count++;
 819                 dbg("%s - line control command being issued", __func__);
 820                 spin_unlock_irqrestore(&priv->lock, flags);
 821                 goto send;
 822         } else
 823                 spin_unlock_irqrestore(&priv->lock, flags);
 824
 825         count = cypress_buf_get(priv->buf, &port->interrupt_out_buffer[offset],
 826                                 port->interrupt_out_size-offset);
 827
 828         if (count == 0) {
 829                 return;
 830         }
 831
 832         switch (priv->pkt_fmt) {
 833         default:
 834         case packet_format_1:
 835                 port->interrupt_out_buffer[1] = count;
 836                 break;
 837         case packet_format_2:
 838                 port->interrupt_out_buffer[0] |= count;
 839         }
 840
 841         dbg("%s - count is %d", __func__, count);
 842
 843 send:
 844         spin_lock_irqsave(&priv->lock, flags);
 845         priv->write_urb_in_use = 1;
 846         spin_unlock_irqrestore(&priv->lock, flags);
 847
 848         if (priv->cmd_ctrl)
 849                 actual_size = 1;
 850         else
 851                 actual_size = count +
 852                               (priv->pkt_fmt == packet_format_1 ? 2 : 1);
 853
 854         usb_serial_debug_data(debug, &port->dev, __func__, port->interrupt_out_size,
 855                               port->interrupt_out_urb->transfer_buffer);
 856
 857         usb_fill_int_urb(port->interrupt_out_urb, port->serial->dev,
 858                 usb_sndintpipe(port->serial->dev, port->interrupt_out_endpointAddress),
 859                 port->interrupt_out_buffer, port->interrupt_out_size,
 860                 cypress_write_int_callback, port, priv->write_urb_interval);
 861         result = usb_submit_urb (port->interrupt_out_urb, GFP_ATOMIC);
 862         if (result) {
 863                 dev_err(&port->dev, "%s - failed submitting write urb, error %d\n", __func__,
 864                         result);
 865                 priv->write_urb_in_use = 0;
 866                 cypress_set_dead(port);
 867         }
 868
 869         spin_lock_irqsave(&priv->lock, flags);
 870         if (priv->cmd_ctrl) {
 871                 priv->cmd_ctrl = 0;
 872         }
 873         priv->bytes_out += count; /* do not count the line control and size bytes */
 874         spin_unlock_irqrestore(&priv->lock, flags);
 875
 876         usb_serial_port_softint(port);
 877 } /* cypress_send */
 878
 879
 880 /* returns how much space is available in the soft buffer */
 881 static int cypress_write_room(struct usb_serial_port *port)
 882 {
 883         struct cypress_private *priv = usb_get_serial_port_data(port);
 884         int room = 0;
 885         unsigned long flags;
 886
 887         dbg("%s - port %d", __func__, port->number);
 888
 889         spin_lock_irqsave(&priv->lock, flags);
 890         room = cypress_buf_space_avail(priv->buf);
 891         spin_unlock_irqrestore(&priv->lock, flags);
 892
 893         dbg("%s - returns %d", __func__, room);
 894         return room;
 895 }
 896
 897
 898 static int cypress_tiocmget (struct usb_serial_port *port, struct file *file)
 899 {
 900         struct cypress_private *priv = usb_get_serial_port_data(port);
 901         __u8 status, control;
 902         unsigned int result = 0;
 903         unsigned long flags;
 904
 905         dbg("%s - port %d", __func__, port->number);
 906
 907         spin_lock_irqsave(&priv->lock, flags);
 908         control = priv->line_control;
 909         status = priv->current_status;
 910         spin_unlock_irqrestore(&priv->lock, flags);
 911
 912         result = ((control & CONTROL_DTR)        ? TIOCM_DTR : 0)
 913                 | ((control & CONTROL_RTS)       ? TIOCM_RTS : 0)
 914                 | ((status & UART_CTS)        ? TIOCM_CTS : 0)
 915                 | ((status & UART_DSR)        ? TIOCM_DSR : 0)
 916                 | ((status & UART_RI)         ? TIOCM_RI  : 0)
 917                 | ((status & UART_CD)         ? TIOCM_CD  : 0);
 918
 919         dbg("%s - result = %x", __func__, result);
 920
 921         return result;
 922 }
 923
 924
 925 static int cypress_tiocmset (struct usb_serial_port *port, struct file *file,
 926                                unsigned int set, unsigned int clear)
 927 {
 928         struct cypress_private *priv = usb_get_serial_port_data(port);
 929         unsigned long flags;
 930
 931         dbg("%s - port %d", __func__, port->number);
 932
 933         spin_lock_irqsave(&priv->lock, flags);
 934         if (set & TIOCM_RTS)
 935                 priv->line_control |= CONTROL_RTS;
 936         if (set & TIOCM_DTR)
 937                 priv->line_control |= CONTROL_DTR;
 938         if (clear & TIOCM_RTS)
 939                 priv->line_control &= ~CONTROL_RTS;
 940         if (clear & TIOCM_DTR)
 941                 priv->line_control &= ~CONTROL_DTR;
 942         priv->cmd_ctrl = 1;
 943         spin_unlock_irqrestore(&priv->lock, flags);
 944
 945         return cypress_write(port, NULL, 0);
 946 }
 947
 948
 949 static int cypress_ioctl (struct usb_serial_port *port, struct file * file, unsigned int cmd, unsigned long arg)
 950 {
 951         struct cypress_private *priv = usb_get_serial_port_data(port);
 952
 953         dbg("%s - port %d, cmd 0x%.4x", __func__, port->number, cmd);
 954
 955         switch (cmd) {
 956                 /* This code comes from drivers/char/serial.c and ftdi_sio.c */
 957                 case TIOCMIWAIT:
 958                         while (priv != NULL) {
 959                                 interruptible_sleep_on(&priv->delta_msr_wait);
 960                                 /* see if a signal did it */
 961                                 if (signal_pending(current))
 962                                         return -ERESTARTSYS;
 963                                 else {
 964                                         char diff = priv->diff_status;
 965
 966                                         if (diff == 0) {
 967                                                 return -EIO; /* no change => error */
 968                                         }
 969
 970                                         /* consume all events */
 971                                         priv->diff_status = 0;
 972
 973                                         /* return 0 if caller wanted to know about these bits */
 974                                         if ( ((arg & TIOCM_RNG) && (diff & UART_RI)) ||
 975                                              ((arg & TIOCM_DSR) && (diff & UART_DSR)) ||
 976                                              ((arg & TIOCM_CD) && (diff & UART_CD)) ||
 977                                              ((arg & TIOCM_CTS) && (diff & UART_CTS)) ) {
 978                                                 return 0;
 979                                         }
 980                                         /* otherwise caller can't care less about what happened,
 981                                          * and so we continue to wait for more events.
 982                                          */
 983                                 }
 984                         }
 985                         return 0;
 986                         break;
 987                 default:
 988                         break;
 989         }
 990
 991         dbg("%s - arg not supported - it was 0x%04x - check include/asm/ioctls.h", __func__, cmd);
 992
 993         return -ENOIOCTLCMD;
 994 } /* cypress_ioctl */
 995
 996
 997 static void cypress_set_termios (struct usb_serial_port *port,
 998                 struct ktermios *old_termios)
 999 {
1000         struct cypress_private *priv = usb_get_serial_port_data(port);
1001         struct tty_struct *tty;
1002         int data_bits, stop_bits, parity_type, parity_enable;
1003         unsigned cflag, iflag;
1004         unsigned long flags;
1005         __u8 oldlines;
1006         int linechange = 0;
1007
1008         dbg("%s - port %d", __func__, port->number);
1009
1010         tty = port->tty;
1011
1012         spin_lock_irqsave(&priv->lock, flags);
1013         if (!priv->termios_initialized) {
1014                 if (priv->chiptype == CT_EARTHMATE) {
1015                         *(tty->termios) = tty_std_termios;
1016                         tty->termios->c_cflag = B4800 | CS8 | CREAD | HUPCL |
1017                                 CLOCAL;
1018                         tty->termios->c_ispeed = 4800;
1019                         tty->termios->c_ospeed = 4800;
1020                 } else if (priv->chiptype == CT_CYPHIDCOM) {
1021                         *(tty->termios) = tty_std_termios;
1022                         tty->termios->c_cflag = B9600 | CS8 | CREAD | HUPCL |
1023                                 CLOCAL;
1024                         tty->termios->c_ispeed = 9600;
1025                         tty->termios->c_ospeed = 9600;
1026                 } else if (priv->chiptype == CT_CA42V2) {
1027                         *(tty->termios) = tty_std_termios;
1028                         tty->termios->c_cflag = B9600 | CS8 | CREAD | HUPCL |
1029                                 CLOCAL;
1030                         tty->termios->c_ispeed = 9600;
1031                         tty->termios->c_ospeed = 9600;
1032                 }
1033                 priv->termios_initialized = 1;
1034         }
1035         spin_unlock_irqrestore(&priv->lock, flags);
1036
1037         /* Unsupported features need clearing */
1038         tty->termios->c_cflag &= ~(CMSPAR|CRTSCTS);
1039
1040         cflag = tty->termios->c_cflag;
1041         iflag = tty->termios->c_iflag;
1042
1043         /* check if there are new settings */
1044         if (old_termios) {
1045                 spin_lock_irqsave(&priv->lock, flags);
1046                 priv->tmp_termios = *(tty->termios);
1047                 spin_unlock_irqrestore(&priv->lock, flags);
1048         }
1049
1050         /* set number of data bits, parity, stop bits */
1051         /* when parity is disabled the parity type bit is ignored */
1052
1053         /* 1 means 2 stop bits, 0 means 1 stop bit */
1054         stop_bits = cflag & CSTOPB ? 1 : 0;
1055
1056         if (cflag & PARENB) {
1057                 parity_enable = 1;
1058                 /* 1 means odd parity, 0 means even parity */
1059                 parity_type = cflag & PARODD ? 1 : 0;
1060         } else
1061                 parity_enable = parity_type = 0;
1062
1063         if (cflag & CSIZE) {
1064                 switch (cflag & CSIZE) {
1065                         case CS5:
1066                                 data_bits = 0;
1067                                 break;
1068                         case CS6:
1069                                 data_bits = 1;
1070                                 break;
1071                         case CS7:
1072                                 data_bits = 2;
1073                                 break;
1074                         case CS8:
1075                                 data_bits = 3;
1076                                 break;
1077                         default:
1078                                 err("%s - CSIZE was set, but not CS5-CS8",
1079                                                 __func__);
1080                                 data_bits = 3;
1081                 }
1082         } else
1083                 data_bits = 3;
1084
1085         spin_lock_irqsave(&priv->lock, flags);
1086         oldlines = priv->line_control;
1087         if ((cflag & CBAUD) == B0) {
1088                 /* drop dtr and rts */
1089                 dbg("%s - dropping the lines, baud rate 0bps", __func__);
1090                 priv->line_control &= ~(CONTROL_DTR | CONTROL_RTS);
1091         } else
1092                 priv->line_control = (CONTROL_DTR | CONTROL_RTS);
1093         spin_unlock_irqrestore(&priv->lock, flags);
1094
1095         dbg("%s - sending %d stop_bits, %d parity_enable, %d parity_type, "
1096                         "%d data_bits (+5)", __func__, stop_bits,
1097                         parity_enable, parity_type, data_bits);
1098
1099         cypress_serial_control(port, tty_get_baud_rate(tty), data_bits, stop_bits,
1100                         parity_enable, parity_type, 0, CYPRESS_SET_CONFIG);
1101
1102         /* we perform a CYPRESS_GET_CONFIG so that the current settings are
1103          * filled into the private structure this should confirm that all is
1104          * working if it returns what we just set */
1105         cypress_serial_control(port, 0, 0, 0, 0, 0, 0, CYPRESS_GET_CONFIG);
1106
1107         /* Here we can define custom tty settings for devices; the main tty
1108          * termios flag base comes from empeg.c */
1109
1110         spin_lock_irqsave(&priv->lock, flags);
1111         if ( (priv->chiptype == CT_EARTHMATE) && (priv->baud_rate == 4800) ) {
1112                 dbg("Using custom termios settings for a baud rate of "
1113                                 "4800bps.");
1114                 /* define custom termios settings for NMEA protocol */
1115
1116                 tty->termios->c_iflag /* input modes - */
1117                         &= ~(IGNBRK  /* disable ignore break */
1118                         | BRKINT     /* disable break causes interrupt */
1119                         | PARMRK     /* disable mark parity errors */
1120                         | ISTRIP     /* disable clear high bit of input char */
1121                         | INLCR      /* disable translate NL to CR */
1122                         | IGNCR      /* disable ignore CR */
1123                         | ICRNL      /* disable translate CR to NL */
1124                         | IXON);     /* disable enable XON/XOFF flow control */
1125
1126                 tty->termios->c_oflag /* output modes */
1127                         &= ~OPOST;    /* disable postprocess output char */
1128
1129                 tty->termios->c_lflag /* line discipline modes */
1130                         &= ~(ECHO     /* disable echo input characters */
1131                         | ECHONL      /* disable echo new line */
1132                         | ICANON      /* disable erase, kill, werase, and rprnt
1133                                          special characters */
1134                         | ISIG        /* disable interrupt, quit, and suspend
1135                                          special characters */
1136                         | IEXTEN);    /* disable non-POSIX special characters */
1137         } /* CT_CYPHIDCOM: Application should handle this for device */
1138
1139         linechange = (priv->line_control != oldlines);
1140         spin_unlock_irqrestore(&priv->lock, flags);
1141
1142         /* if necessary, set lines */
1143         if (linechange) {
1144                 priv->cmd_ctrl = 1;
1145                 cypress_write(port, NULL, 0);
1146         }
1147 } /* cypress_set_termios */
1148
1149
1150 /* returns amount of data still left in soft buffer */
1151 static int cypress_chars_in_buffer(struct usb_serial_port *port)
1152 {
1153         struct cypress_private *priv = usb_get_serial_port_data(port);
1154         int chars = 0;
1155         unsigned long flags;
1156
1157         dbg("%s - port %d", __func__, port->number);
1158
1159         spin_lock_irqsave(&priv->lock, flags);
1160         chars = cypress_buf_data_avail(priv->buf);
1161         spin_unlock_irqrestore(&priv->lock, flags);
1162
1163         dbg("%s - returns %d", __func__, chars);
1164         return chars;
1165 }
1166
1167
1168 static void cypress_throttle (struct usb_serial_port *port)
1169 {
1170         struct cypress_private *priv = usb_get_serial_port_data(port);
1171         unsigned long flags;
1172
1173         dbg("%s - port %d", __func__, port->number);
1174
1175         spin_lock_irqsave(&priv->lock, flags);
1176         priv->rx_flags = THROTTLED;
1177         spin_unlock_irqrestore(&priv->lock, flags);
1178 }
1179
1180
1181 static void cypress_unthrottle (struct usb_serial_port *port)
1182 {
1183         struct cypress_private *priv = usb_get_serial_port_data(port);
1184         int actually_throttled, result;
1185         unsigned long flags;
1186
1187         dbg("%s - port %d", __func__, port->number);
1188
1189         spin_lock_irqsave(&priv->lock, flags);
1190         actually_throttled = priv->rx_flags & ACTUALLY_THROTTLED;
1191         priv->rx_flags = 0;
1192         spin_unlock_irqrestore(&priv->lock, flags);
1193
1194         if (!priv->comm_is_ok)
1195                 return;
1196
1197         if (actually_throttled) {
1198                 port->interrupt_in_urb->dev = port->serial->dev;
1199
1200                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1201                 if (result) {
1202                         dev_err(&port->dev, "%s - failed submitting read urb, "
1203                                         "error %d\n", __func__, result);
1204                         cypress_set_dead(port);
1205                 }
1206         }
1207 }
1208
1209
1210 static void cypress_read_int_callback(struct urb *urb)
1211 {
1212         struct usb_serial_port *port = urb->context;
1213         struct cypress_private *priv = usb_get_serial_port_data(port);
1214         struct tty_struct *tty;
1215         unsigned char *data = urb->transfer_buffer;
1216         unsigned long flags;
1217         char tty_flag = TTY_NORMAL;
1218         int havedata = 0;
1219         int bytes = 0;
1220         int result;
1221         int i = 0;
1222         int status = urb->status;
1223
1224         dbg("%s - port %d", __func__, port->number);
1225
1226         switch (status) {
1227         case 0: /* success */
1228                 break;
1229         case -ECONNRESET:
1230         case -ENOENT:
1231         case -ESHUTDOWN:
1232                 /* precursor to disconnect so just go away */
1233                 return;
1234         case -EPIPE:
1235                 usb_clear_halt(port->serial->dev,0x81);
1236                 break;
1237         default:
1238                 /* something ugly is going on... */
1239                 dev_err(&urb->dev->dev,"%s - unexpected nonzero read status received: %d\n",
1240                         __func__, status);
1241                 cypress_set_dead(port);
1242                 return;
1243         }
1244
1245         spin_lock_irqsave(&priv->lock, flags);
1246         if (priv->rx_flags & THROTTLED) {
1247                 dbg("%s - now throttling", __func__);
1248                 priv->rx_flags |= ACTUALLY_THROTTLED;
1249                 spin_unlock_irqrestore(&priv->lock, flags);
1250                 return;
1251         }
1252         spin_unlock_irqrestore(&priv->lock, flags);
1253
1254         tty = port->tty;
1255         if (!tty) {
1256                 dbg("%s - bad tty pointer - exiting", __func__);
1257                 return;
1258         }
1259
1260         spin_lock_irqsave(&priv->lock, flags);
1261         result = urb->actual_length;
1262         switch (priv->pkt_fmt) {
1263         default:
1264         case packet_format_1:
1265                 /* This is for the CY7C64013... */
1266                 priv->current_status = data[0] & 0xF8;
1267                 bytes = data[1] + 2;
1268                 i = 2;
1269                 if (bytes > 2)
1270                         havedata = 1;
1271                 break;
1272         case packet_format_2:
1273                 /* This is for the CY7C63743... */
1274                 priv->current_status = data[0] & 0xF8;
1275                 bytes = (data[0] & 0x07) + 1;
1276                 i = 1;
1277                 if (bytes > 1)
1278                         havedata = 1;
1279                 break;
1280         }
1281         spin_unlock_irqrestore(&priv->lock, flags);
1282         if (result < bytes) {
1283                 dbg("%s - wrong packet size - received %d bytes but packet "
1284                     "said %d bytes", __func__, result, bytes);
1285                 goto continue_read;
1286         }
1287
1288         usb_serial_debug_data (debug, &port->dev, __func__,
1289                         urb->actual_length, data);
1290
1291         spin_lock_irqsave(&priv->lock, flags);
1292         /* check to see if status has changed */
1293         if (priv->current_status != priv->prev_status) {
1294                 priv->diff_status |= priv->current_status ^
1295                         priv->prev_status;
1296                 wake_up_interruptible(&priv->delta_msr_wait);
1297                 priv->prev_status = priv->current_status;
1298         }
1299         spin_unlock_irqrestore(&priv->lock, flags);
1300
1301         /* hangup, as defined in acm.c... this might be a bad place for it
1302          * though */
1303         if (tty && !(tty->termios->c_cflag & CLOCAL) &&
1304                         !(priv->current_status & UART_CD)) {
1305                 dbg("%s - calling hangup", __func__);
1306                 tty_hangup(tty);
1307                 goto continue_read;
1308         }
1309
1310         /* There is one error bit... I'm assuming it is a parity error
1311          * indicator as the generic firmware will set this bit to 1 if a
1312          * parity error occurs.
1313          * I can not find reference to any other error events. */
1314         spin_lock_irqsave(&priv->lock, flags);
1315         if (priv->current_status & CYP_ERROR) {
1316                 spin_unlock_irqrestore(&priv->lock, flags);
1317                 tty_flag = TTY_PARITY;
1318                 dbg("%s - Parity Error detected", __func__);
1319         } else
1320                 spin_unlock_irqrestore(&priv->lock, flags);
1321
1322         /* process read if there is data other than line status */
1323         if (tty && (bytes > i)) {
1324                 bytes = tty_buffer_request_room(tty, bytes);
1325                 for (; i < bytes ; ++i) {
1326                         dbg("pushing byte number %d - %d - %c", i, data[i],
1327                                         data[i]);
1328                         tty_insert_flip_char(tty, data[i], tty_flag);
1329                 }
1330                 tty_flip_buffer_push(port->tty);
1331         }
1332
1333         spin_lock_irqsave(&priv->lock, flags);
1334         /* control and status byte(s) are also counted */
1335         priv->bytes_in += bytes;
1336         spin_unlock_irqrestore(&priv->lock, flags);
1337
1338 continue_read:
1339
1340         /* Continue trying to always read... unless the port has closed. */
1341
1342         if (port->open_count > 0 && priv->comm_is_ok) {
1343                 usb_fill_int_urb(port->interrupt_in_urb, port->serial->dev,
1344                                 usb_rcvintpipe(port->serial->dev,
1345                                         port->interrupt_in_endpointAddress),
1346                                 port->interrupt_in_urb->transfer_buffer,
1347                                 port->interrupt_in_urb->transfer_buffer_length,
1348                                 cypress_read_int_callback, port, priv->read_urb_interval);
1349                 result = usb_submit_urb(port->interrupt_in_urb, GFP_ATOMIC);
1350                 if (result) {
1351                         dev_err(&urb->dev->dev, "%s - failed resubmitting "
1352                                         "read urb, error %d\n", __func__,
1353                                         result);
1354                         cypress_set_dead(port);
1355                 }
1356         }
1357
1358         return;
1359 } /* cypress_read_int_callback */
1360
1361
1362 static void cypress_write_int_callback(struct urb *urb)
1363 {
1364         struct usb_serial_port *port = urb->context;
1365         struct cypress_private *priv = usb_get_serial_port_data(port);
1366         int result;
1367         int status = urb->status;
1368
1369         dbg("%s - port %d", __func__, port->number);
1370
1371         switch (status) {
1372                 case 0:
1373                         /* success */
1374                         break;
1375                 case -ECONNRESET:
1376                 case -ENOENT:
1377                 case -ESHUTDOWN:
1378                         /* this urb is terminated, clean up */
1379                         dbg("%s - urb shutting down with status: %d",
1380                             __func__, status);
1381                         priv->write_urb_in_use = 0;
1382                         return;
1383                 case -EPIPE: /* no break needed; clear halt and resubmit */
1384                         if (!priv->comm_is_ok)
1385                                 break;
1386                         usb_clear_halt(port->serial->dev, 0x02);
1387                         /* error in the urb, so we have to resubmit it */
1388                         dbg("%s - nonzero write bulk status received: %d",
1389                             __func__, status);
1390                         port->interrupt_out_urb->transfer_buffer_length = 1;
1391                         port->interrupt_out_urb->dev = port->serial->dev;
1392                         result = usb_submit_urb(port->interrupt_out_urb, GFP_ATOMIC);
1393                         if (!result)
1394                                 return;
1395                         dev_err(&urb->dev->dev, "%s - failed resubmitting write urb, error %d\n",
1396                                 __func__, result);
1397                         cypress_set_dead(port);
1398                         break;
1399                 default:
1400                         dev_err(&urb->dev->dev,"%s - unexpected nonzero write status received: %d\n",
1401                                 __func__, status);
1402                         cypress_set_dead(port);
1403                         break;
1404         }
1405
1406         priv->write_urb_in_use = 0;
1407
1408         /* send any buffered data */
1409         cypress_send(port);
1410 }
1411
1412
1413 /*****************************************************************************
1414  * Write buffer functions - buffering code from pl2303 used
1415  *****************************************************************************/
1416
1417 /*
1418  * cypress_buf_alloc
1419  *
1420  * Allocate a circular buffer and all associated memory.
1421  */
1422
1423 static struct cypress_buf *cypress_buf_alloc(unsigned int size)
1424 {
1425
1426         struct cypress_buf *cb;
1427
1428
1429         if (size == 0)
1430                 return NULL;
1431
1432         cb = kmalloc(sizeof(struct cypress_buf), GFP_KERNEL);
1433         if (cb == NULL)
1434                 return NULL;
1435
1436         cb->buf_buf = kmalloc(size, GFP_KERNEL);
1437         if (cb->buf_buf == NULL) {
1438                 kfree(cb);
1439                 return NULL;
1440         }
1441
1442         cb->buf_size = size;
1443         cb->buf_get = cb->buf_put = cb->buf_buf;
1444
1445         return cb;
1446
1447 }
1448
1449
1450 /*
1451  * cypress_buf_free
1452  *
1453  * Free the buffer and all associated memory.
1454  */
1455
1456 static void cypress_buf_free(struct cypress_buf *cb)
1457 {
1458         if (cb) {
1459                 kfree(cb->buf_buf);
1460                 kfree(cb);
1461         }
1462 }
1463
1464
1465 /*
1466  * cypress_buf_clear
1467  *
1468  * Clear out all data in the circular buffer.
1469  */
1470
1471 static void cypress_buf_clear(struct cypress_buf *cb)
1472 {
1473         if (cb != NULL)
1474                 cb->buf_get = cb->buf_put;
1475                 /* equivalent to a get of all data available */
1476 }
1477
1478
1479 /*
1480  * cypress_buf_data_avail
1481  *
1482  * Return the number of bytes of data available in the circular
1483  * buffer.
1484  */
1485
1486 static unsigned int cypress_buf_data_avail(struct cypress_buf *cb)
1487 {
1488         if (cb != NULL)
1489                 return ((cb->buf_size + cb->buf_put - cb->buf_get) % cb->buf_size);
1490         else
1491                 return 0;
1492 }
1493
1494
1495 /*
1496  * cypress_buf_space_avail
1497  *
1498  * Return the number of bytes of space available in the circular
1499  * buffer.
1500  */
1501
1502 static unsigned int cypress_buf_space_avail(struct cypress_buf *cb)
1503 {
1504         if (cb != NULL)
1505                 return ((cb->buf_size + cb->buf_get - cb->buf_put - 1) % cb->buf_size);
1506         else
1507                 return 0;
1508 }
1509
1510
1511 /*
1512  * cypress_buf_put
1513  *
1514  * Copy data data from a user buffer and put it into the circular buffer.
1515  * Restrict to the amount of space available.
1516  *
1517  * Return the number of bytes copied.
1518  */
1519
1520 static unsigned int cypress_buf_put(struct cypress_buf *cb, const char *buf,
1521         unsigned int count)
1522 {
1523
1524         unsigned int len;
1525
1526
1527         if (cb == NULL)
1528                 return 0;
1529
1530         len  = cypress_buf_space_avail(cb);
1531         if (count > len)
1532                 count = len;
1533
1534         if (count == 0)
1535                 return 0;
1536
1537         len = cb->buf_buf + cb->buf_size - cb->buf_put;
1538         if (count > len) {
1539                 memcpy(cb->buf_put, buf, len);
1540                 memcpy(cb->buf_buf, buf+len, count - len);
1541                 cb->buf_put = cb->buf_buf + count - len;
1542         } else {
1543                 memcpy(cb->buf_put, buf, count);
1544                 if (count < len)
1545                         cb->buf_put += count;
1546                 else /* count == len */
1547                         cb->buf_put = cb->buf_buf;
1548         }
1549
1550         return count;
1551
1552 }
1553
1554
1555 /*
1556  * cypress_buf_get
1557  *
1558  * Get data from the circular buffer and copy to the given buffer.
1559  * Restrict to the amount of data available.
1560  *
1561  * Return the number of bytes copied.
1562  */
1563
1564 static unsigned int cypress_buf_get(struct cypress_buf *cb, char *buf,
1565         unsigned int count)
1566 {
1567
1568         unsigned int len;
1569
1570
1571         if (cb == NULL)
1572                 return 0;
1573
1574         len = cypress_buf_data_avail(cb);
1575         if (count > len)
1576                 count = len;
1577
1578         if (count == 0)
1579                 return 0;
1580
1581         len = cb->buf_buf + cb->buf_size - cb->buf_get;
1582         if (count > len) {
1583                 memcpy(buf, cb->buf_get, len);
1584                 memcpy(buf+len, cb->buf_buf, count - len);
1585                 cb->buf_get = cb->buf_buf + count - len;
1586         } else {
1587                 memcpy(buf, cb->buf_get, count);
1588                 if (count < len)
1589                         cb->buf_get += count;
1590                 else /* count == len */
1591                         cb->buf_get = cb->buf_buf;
1592         }
1593
1594         return count;
1595
1596 }
1597
1598 /*****************************************************************************
1599  * Module functions
1600  *****************************************************************************/
1601
1602 static int __init cypress_init(void)
1603 {
1604         int retval;
1605
1606         dbg("%s", __func__);
1607
1608         retval = usb_serial_register(&cypress_earthmate_device);
1609         if (retval)
1610                 goto failed_em_register;
1611         retval = usb_serial_register(&cypress_hidcom_device);
1612         if (retval)
1613                 goto failed_hidcom_register;
1614         retval = usb_serial_register(&cypress_ca42v2_device);
1615         if (retval)
1616                 goto failed_ca42v2_register;
1617         retval = usb_register(&cypress_driver);
1618         if (retval)
1619                 goto failed_usb_register;
1620
1621         info(DRIVER_DESC " " DRIVER_VERSION);
1622         return 0;
1623
1624 failed_usb_register:
1625         usb_serial_deregister(&cypress_ca42v2_device);
1626 failed_ca42v2_register:
1627         usb_serial_deregister(&cypress_hidcom_device);
1628 failed_hidcom_register:
1629         usb_serial_deregister(&cypress_earthmate_device);
1630 failed_em_register:
1631         return retval;
1632 }
1633
1634
1635 static void __exit cypress_exit (void)
1636 {
1637         dbg("%s", __func__);
1638
1639         usb_deregister (&cypress_driver);
1640         usb_serial_deregister (&cypress_earthmate_device);
1641         usb_serial_deregister (&cypress_hidcom_device);
1642         usb_serial_deregister (&cypress_ca42v2_device);
1643 }
1644
1645
1646 module_init(cypress_init);
1647 module_exit(cypress_exit);
1648
1649 MODULE_AUTHOR( DRIVER_AUTHOR );
1650 MODULE_DESCRIPTION( DRIVER_DESC );
1651 MODULE_VERSION( DRIVER_VERSION );
1652 MODULE_LICENSE("GPL");
1653
1654 module_param(debug, bool, S_IRUGO | S_IWUSR);
1655 MODULE_PARM_DESC(debug, "Debug enabled or not");
1656 module_param(stats, bool, S_IRUGO | S_IWUSR);
1657 MODULE_PARM_DESC(stats, "Enable statistics or not");
1658 module_param(interval, int, S_IRUGO | S_IWUSR);
1659 MODULE_PARM_DESC(interval, "Overrides interrupt interval");