watchdog: Get rid of MODULE_ALIAS_MISCDEV statements
[sfrench/cifs-2.6.git] / drivers / watchdog / pcwd_usb.c
1 /*
2  *      Berkshire USB-PC Watchdog Card Driver
3  *
4  *      (c) Copyright 2004-2007 Wim Van Sebroeck <wim@iguana.be>.
5  *
6  *      Based on source code of the following authors:
7  *        Ken Hollis <kenji@bitgate.com>,
8  *        Alan Cox <alan@lxorguk.ukuu.org.uk>,
9  *        Matt Domsch <Matt_Domsch@dell.com>,
10  *        Rob Radez <rob@osinvestor.com>,
11  *        Greg Kroah-Hartman <greg@kroah.com>
12  *
13  *      This program is free software; you can redistribute it and/or
14  *      modify it under the terms of the GNU General Public License
15  *      as published by the Free Software Foundation; either version
16  *      2 of the License, or (at your option) any later version.
17  *
18  *      Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
19  *      provide warranty for any of this software. This material is
20  *      provided "AS-IS" and at no charge.
21  *
22  *      Thanks also to Simon Machell at Berkshire Products Inc. for
23  *      providing the test hardware. More info is available at
24  *      http://www.berkprod.com/ or http://www.pcwatchdog.com/
25  */
26
27 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
28
29 #include <linux/module.h>       /* For module specific items */
30 #include <linux/moduleparam.h>  /* For new moduleparam's */
31 #include <linux/types.h>        /* For standard types (like size_t) */
32 #include <linux/errno.h>        /* For the -ENODEV/... values */
33 #include <linux/kernel.h>       /* For printk/panic/... */
34 #include <linux/delay.h>        /* For mdelay function */
35 #include <linux/miscdevice.h>   /* For struct miscdevice */
36 #include <linux/watchdog.h>     /* For the watchdog specific items */
37 #include <linux/notifier.h>     /* For notifier support */
38 #include <linux/reboot.h>       /* For reboot_notifier stuff */
39 #include <linux/init.h>         /* For __init/__exit/... */
40 #include <linux/fs.h>           /* For file operations */
41 #include <linux/usb.h>          /* For USB functions */
42 #include <linux/slab.h>         /* For kmalloc, ... */
43 #include <linux/mutex.h>        /* For mutex locking */
44 #include <linux/hid.h>          /* For HID_REQ_SET_REPORT & HID_DT_REPORT */
45 #include <linux/uaccess.h>      /* For copy_to_user/put_user/... */
46
47 #ifdef CONFIG_USB_DEBUG
48 static int debug = 1;
49 #else
50 static int debug;
51 #endif
52
53 /* Use our own dbg macro */
54
55 #undef dbg
56 #ifndef DEBUG
57 #define DEBUG
58 #endif
59 #define dbg(format, ...)                                \
60 do {                                                    \
61         if (debug)                                      \
62                 pr_debug(format "\n", ##__VA_ARGS__);   \
63 } while (0)
64
65 /* Module and Version Information */
66 #define DRIVER_VERSION "1.02"
67 #define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
68 #define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
69 #define DRIVER_LICENSE "GPL"
70 #define DRIVER_NAME "pcwd_usb"
71
72 MODULE_AUTHOR(DRIVER_AUTHOR);
73 MODULE_DESCRIPTION(DRIVER_DESC);
74 MODULE_LICENSE(DRIVER_LICENSE);
75
76 /* Module Parameters */
77 module_param(debug, int, 0);
78 MODULE_PARM_DESC(debug, "Debug enabled or not");
79
80 #define WATCHDOG_HEARTBEAT 0    /* default heartbeat =
81                                                 delay-time from dip-switches */
82 static int heartbeat = WATCHDOG_HEARTBEAT;
83 module_param(heartbeat, int, 0);
84 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. "
85         "(0<heartbeat<65536 or 0=delay-time from dip-switches, default="
86                                 __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
87
88 static bool nowayout = WATCHDOG_NOWAYOUT;
89 module_param(nowayout, bool, 0);
90 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
91                                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
92
93 /* The vendor and product id's for the USB-PC Watchdog card */
94 #define USB_PCWD_VENDOR_ID      0x0c98
95 #define USB_PCWD_PRODUCT_ID     0x1140
96
97 /* table of devices that work with this driver */
98 static struct usb_device_id usb_pcwd_table[] = {
99         { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
100         { }                                     /* Terminating entry */
101 };
102 MODULE_DEVICE_TABLE(usb, usb_pcwd_table);
103
104 /* according to documentation max. time to process a command for the USB
105  * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */
106 #define USB_COMMAND_TIMEOUT     250
107
108 /* Watchdog's internal commands */
109 #define CMD_READ_TEMP                   0x02    /* Read Temperature;
110                                                         Re-trigger Watchdog */
111 #define CMD_TRIGGER                     CMD_READ_TEMP
112 #define CMD_GET_STATUS                  0x04    /* Get Status Information */
113 #define CMD_GET_FIRMWARE_VERSION        0x08    /* Get Firmware Version */
114 #define CMD_GET_DIP_SWITCH_SETTINGS     0x0c    /* Get Dip Switch Settings */
115 #define CMD_READ_WATCHDOG_TIMEOUT       0x18    /* Read Current Watchdog Time */
116 #define CMD_WRITE_WATCHDOG_TIMEOUT      0x19    /* Write Current WatchdogTime */
117 #define CMD_ENABLE_WATCHDOG             0x30    /* Enable / Disable Watchdog */
118 #define CMD_DISABLE_WATCHDOG            CMD_ENABLE_WATCHDOG
119
120 /* Watchdog's Dip Switch heartbeat values */
121 static const int heartbeat_tbl[] = {
122         5,      /* OFF-OFF-OFF  =  5 Sec  */
123         10,     /* OFF-OFF-ON   = 10 Sec  */
124         30,     /* OFF-ON-OFF   = 30 Sec  */
125         60,     /* OFF-ON-ON    =  1 Min  */
126         300,    /* ON-OFF-OFF   =  5 Min  */
127         600,    /* ON-OFF-ON    = 10 Min  */
128         1800,   /* ON-ON-OFF    = 30 Min  */
129         3600,   /* ON-ON-ON     =  1 hour */
130 };
131
132 /* We can only use 1 card due to the /dev/watchdog restriction */
133 static int cards_found;
134
135 /* some internal variables */
136 static unsigned long is_active;
137 static char expect_release;
138
139 /* Structure to hold all of our device specific stuff */
140 struct usb_pcwd_private {
141         /* save off the usb device pointer */
142         struct usb_device       *udev;
143         /* the interface for this device */
144         struct usb_interface    *interface;
145
146         /* the interface number used for cmd's */
147         unsigned int            interface_number;
148
149         /* the buffer to intr data */
150         unsigned char           *intr_buffer;
151         /* the dma address for the intr buffer */
152         dma_addr_t              intr_dma;
153         /* the size of the intr buffer */
154         size_t                  intr_size;
155         /* the urb used for the intr pipe */
156         struct urb              *intr_urb;
157
158         /* The command that is reported back */
159         unsigned char           cmd_command;
160         /* The data MSB that is reported back */
161         unsigned char           cmd_data_msb;
162         /* The data LSB that is reported back */
163         unsigned char           cmd_data_lsb;
164         /* true if we received a report after a command */
165         atomic_t                cmd_received;
166
167         /* Wether or not the device exists */
168         int                     exists;
169         /* locks this structure */
170         struct mutex            mtx;
171 };
172 static struct usb_pcwd_private *usb_pcwd_device;
173
174 /* prevent races between open() and disconnect() */
175 static DEFINE_MUTEX(disconnect_mutex);
176
177 /* local function prototypes */
178 static int usb_pcwd_probe(struct usb_interface *interface,
179                                                 const struct usb_device_id *id);
180 static void usb_pcwd_disconnect(struct usb_interface *interface);
181
182 /* usb specific object needed to register this driver with the usb subsystem */
183 static struct usb_driver usb_pcwd_driver = {
184         .name =         DRIVER_NAME,
185         .probe =        usb_pcwd_probe,
186         .disconnect =   usb_pcwd_disconnect,
187         .id_table =     usb_pcwd_table,
188 };
189
190
191 static void usb_pcwd_intr_done(struct urb *urb)
192 {
193         struct usb_pcwd_private *usb_pcwd =
194                                 (struct usb_pcwd_private *)urb->context;
195         unsigned char *data = usb_pcwd->intr_buffer;
196         int retval;
197
198         switch (urb->status) {
199         case 0:                 /* success */
200                 break;
201         case -ECONNRESET:       /* unlink */
202         case -ENOENT:
203         case -ESHUTDOWN:
204                 /* this urb is terminated, clean up */
205                 dbg("%s - urb shutting down with status: %d", __func__,
206                                                                 urb->status);
207                 return;
208         /* -EPIPE:  should clear the halt */
209         default:                /* error */
210                 dbg("%s - nonzero urb status received: %d", __func__,
211                                                                 urb->status);
212                 goto resubmit;
213         }
214
215         dbg("received following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
216                 data[0], data[1], data[2]);
217
218         usb_pcwd->cmd_command  = data[0];
219         usb_pcwd->cmd_data_msb = data[1];
220         usb_pcwd->cmd_data_lsb = data[2];
221
222         /* notify anyone waiting that the cmd has finished */
223         atomic_set(&usb_pcwd->cmd_received, 1);
224
225 resubmit:
226         retval = usb_submit_urb(urb, GFP_ATOMIC);
227         if (retval)
228                 pr_err("can't resubmit intr, usb_submit_urb failed with result %d\n",
229                        retval);
230 }
231
232 static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd,
233                 unsigned char cmd, unsigned char *msb, unsigned char *lsb)
234 {
235         int got_response, count;
236         unsigned char *buf;
237
238         /* We will not send any commands if the USB PCWD device does
239          * not exist */
240         if ((!usb_pcwd) || (!usb_pcwd->exists))
241                 return -1;
242
243         buf = kmalloc(6, GFP_KERNEL);
244         if (buf == NULL)
245                 return 0;
246
247         /* The USB PC Watchdog uses a 6 byte report format.
248          * The board currently uses only 3 of the six bytes of the report. */
249         buf[0] = cmd;                   /* Byte 0 = CMD */
250         buf[1] = *msb;                  /* Byte 1 = Data MSB */
251         buf[2] = *lsb;                  /* Byte 2 = Data LSB */
252         buf[3] = buf[4] = buf[5] = 0;   /* All other bytes not used */
253
254         dbg("sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
255                 buf[0], buf[1], buf[2]);
256
257         atomic_set(&usb_pcwd->cmd_received, 0);
258
259         if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
260                         HID_REQ_SET_REPORT, HID_DT_REPORT,
261                         0x0200, usb_pcwd->interface_number, buf, sizeof(buf),
262                         USB_COMMAND_TIMEOUT) != sizeof(buf)) {
263                 dbg("usb_pcwd_send_command: error in usb_control_msg for "
264                                 "cmd 0x%x 0x%x 0x%x\n", cmd, *msb, *lsb);
265         }
266         /* wait till the usb card processed the command,
267          * with a max. timeout of USB_COMMAND_TIMEOUT */
268         got_response = 0;
269         for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response);
270                                                                 count++) {
271                 mdelay(1);
272                 if (atomic_read(&usb_pcwd->cmd_received))
273                         got_response = 1;
274         }
275
276         if ((got_response) && (cmd == usb_pcwd->cmd_command)) {
277                 /* read back response */
278                 *msb = usb_pcwd->cmd_data_msb;
279                 *lsb = usb_pcwd->cmd_data_lsb;
280         }
281
282         kfree(buf);
283
284         return got_response;
285 }
286
287 static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd)
288 {
289         unsigned char msb = 0x00;
290         unsigned char lsb = 0x00;
291         int retval;
292
293         /* Enable Watchdog */
294         retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG,
295                                                                 &msb, &lsb);
296
297         if ((retval == 0) || (lsb == 0)) {
298                 pr_err("Card did not acknowledge enable attempt\n");
299                 return -1;
300         }
301
302         return 0;
303 }
304
305 static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd)
306 {
307         unsigned char msb = 0xA5;
308         unsigned char lsb = 0xC3;
309         int retval;
310
311         /* Disable Watchdog */
312         retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG,
313                                                                 &msb, &lsb);
314
315         if ((retval == 0) || (lsb != 0)) {
316                 pr_err("Card did not acknowledge disable attempt\n");
317                 return -1;
318         }
319
320         return 0;
321 }
322
323 static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd)
324 {
325         unsigned char dummy;
326
327         /* Re-trigger Watchdog */
328         usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy);
329
330         return 0;
331 }
332
333 static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t)
334 {
335         unsigned char msb = t / 256;
336         unsigned char lsb = t % 256;
337
338         if ((t < 0x0001) || (t > 0xFFFF))
339                 return -EINVAL;
340
341         /* Write new heartbeat to watchdog */
342         usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb);
343
344         heartbeat = t;
345         return 0;
346 }
347
348 static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd,
349                                                         int *temperature)
350 {
351         unsigned char msb, lsb;
352
353         usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
354
355         /*
356          * Convert celsius to fahrenheit, since this was
357          * the decided 'standard' for this return value.
358          */
359         *temperature = (lsb * 9 / 5) + 32;
360
361         return 0;
362 }
363
364 static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd,
365                                                                 int *time_left)
366 {
367         unsigned char msb, lsb;
368
369         /* Read the time that's left before rebooting */
370         /* Note: if the board is not yet armed then we will read 0xFFFF */
371         usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
372
373         *time_left = (msb << 8) + lsb;
374
375         return 0;
376 }
377
378 /*
379  *      /dev/watchdog handling
380  */
381
382 static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
383                                                 size_t len, loff_t *ppos)
384 {
385         /* See if we got the magic character 'V' and reload the timer */
386         if (len) {
387                 if (!nowayout) {
388                         size_t i;
389
390                         /* note: just in case someone wrote the magic character
391                          * five months ago... */
392                         expect_release = 0;
393
394                         /* scan to see whether or not we got the
395                          * magic character */
396                         for (i = 0; i != len; i++) {
397                                 char c;
398                                 if (get_user(c, data + i))
399                                         return -EFAULT;
400                                 if (c == 'V')
401                                         expect_release = 42;
402                         }
403                 }
404
405                 /* someone wrote to us, we should reload the timer */
406                 usb_pcwd_keepalive(usb_pcwd_device);
407         }
408         return len;
409 }
410
411 static long usb_pcwd_ioctl(struct file *file, unsigned int cmd,
412                                                 unsigned long arg)
413 {
414         void __user *argp = (void __user *)arg;
415         int __user *p = argp;
416         static const struct watchdog_info ident = {
417                 .options =              WDIOF_KEEPALIVEPING |
418                                         WDIOF_SETTIMEOUT |
419                                         WDIOF_MAGICCLOSE,
420                 .firmware_version =     1,
421                 .identity =             DRIVER_NAME,
422         };
423
424         switch (cmd) {
425         case WDIOC_GETSUPPORT:
426                 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
427
428         case WDIOC_GETSTATUS:
429         case WDIOC_GETBOOTSTATUS:
430                 return put_user(0, p);
431
432         case WDIOC_GETTEMP:
433         {
434                 int temperature;
435
436                 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
437                         return -EFAULT;
438
439                 return put_user(temperature, p);
440         }
441
442         case WDIOC_SETOPTIONS:
443         {
444                 int new_options, retval = -EINVAL;
445
446                 if (get_user(new_options, p))
447                         return -EFAULT;
448
449                 if (new_options & WDIOS_DISABLECARD) {
450                         usb_pcwd_stop(usb_pcwd_device);
451                         retval = 0;
452                 }
453
454                 if (new_options & WDIOS_ENABLECARD) {
455                         usb_pcwd_start(usb_pcwd_device);
456                         retval = 0;
457                 }
458
459                 return retval;
460         }
461
462         case WDIOC_KEEPALIVE:
463                 usb_pcwd_keepalive(usb_pcwd_device);
464                 return 0;
465
466         case WDIOC_SETTIMEOUT:
467         {
468                 int new_heartbeat;
469
470                 if (get_user(new_heartbeat, p))
471                         return -EFAULT;
472
473                 if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
474                         return -EINVAL;
475
476                 usb_pcwd_keepalive(usb_pcwd_device);
477                 /* Fall */
478         }
479
480         case WDIOC_GETTIMEOUT:
481                 return put_user(heartbeat, p);
482
483         case WDIOC_GETTIMELEFT:
484         {
485                 int time_left;
486
487                 if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left))
488                         return -EFAULT;
489
490                 return put_user(time_left, p);
491         }
492
493         default:
494                 return -ENOTTY;
495         }
496 }
497
498 static int usb_pcwd_open(struct inode *inode, struct file *file)
499 {
500         /* /dev/watchdog can only be opened once */
501         if (test_and_set_bit(0, &is_active))
502                 return -EBUSY;
503
504         /* Activate */
505         usb_pcwd_start(usb_pcwd_device);
506         usb_pcwd_keepalive(usb_pcwd_device);
507         return nonseekable_open(inode, file);
508 }
509
510 static int usb_pcwd_release(struct inode *inode, struct file *file)
511 {
512         /*
513          *      Shut off the timer.
514          */
515         if (expect_release == 42) {
516                 usb_pcwd_stop(usb_pcwd_device);
517         } else {
518                 pr_crit("Unexpected close, not stopping watchdog!\n");
519                 usb_pcwd_keepalive(usb_pcwd_device);
520         }
521         expect_release = 0;
522         clear_bit(0, &is_active);
523         return 0;
524 }
525
526 /*
527  *      /dev/temperature handling
528  */
529
530 static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
531                                 size_t len, loff_t *ppos)
532 {
533         int temperature;
534
535         if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
536                 return -EFAULT;
537
538         if (copy_to_user(data, &temperature, 1))
539                 return -EFAULT;
540
541         return 1;
542 }
543
544 static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
545 {
546         return nonseekable_open(inode, file);
547 }
548
549 static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
550 {
551         return 0;
552 }
553
554 /*
555  *      Notify system
556  */
557
558 static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code,
559                                                                 void *unused)
560 {
561         if (code == SYS_DOWN || code == SYS_HALT)
562                 usb_pcwd_stop(usb_pcwd_device); /* Turn the WDT off */
563
564         return NOTIFY_DONE;
565 }
566
567 /*
568  *      Kernel Interfaces
569  */
570
571 static const struct file_operations usb_pcwd_fops = {
572         .owner =        THIS_MODULE,
573         .llseek =       no_llseek,
574         .write =        usb_pcwd_write,
575         .unlocked_ioctl = usb_pcwd_ioctl,
576         .open =         usb_pcwd_open,
577         .release =      usb_pcwd_release,
578 };
579
580 static struct miscdevice usb_pcwd_miscdev = {
581         .minor =        WATCHDOG_MINOR,
582         .name =         "watchdog",
583         .fops =         &usb_pcwd_fops,
584 };
585
586 static const struct file_operations usb_pcwd_temperature_fops = {
587         .owner =        THIS_MODULE,
588         .llseek =       no_llseek,
589         .read =         usb_pcwd_temperature_read,
590         .open =         usb_pcwd_temperature_open,
591         .release =      usb_pcwd_temperature_release,
592 };
593
594 static struct miscdevice usb_pcwd_temperature_miscdev = {
595         .minor =        TEMP_MINOR,
596         .name =         "temperature",
597         .fops =         &usb_pcwd_temperature_fops,
598 };
599
600 static struct notifier_block usb_pcwd_notifier = {
601         .notifier_call =        usb_pcwd_notify_sys,
602 };
603
604 /**
605  *      usb_pcwd_delete
606  */
607 static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd)
608 {
609         usb_free_urb(usb_pcwd->intr_urb);
610         if (usb_pcwd->intr_buffer != NULL)
611                 usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size,
612                                   usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
613         kfree(usb_pcwd);
614 }
615
616 /**
617  *      usb_pcwd_probe
618  *
619  *      Called by the usb core when a new device is connected that it thinks
620  *      this driver might be interested in.
621  */
622 static int usb_pcwd_probe(struct usb_interface *interface,
623                                                 const struct usb_device_id *id)
624 {
625         struct usb_device *udev = interface_to_usbdev(interface);
626         struct usb_host_interface *iface_desc;
627         struct usb_endpoint_descriptor *endpoint;
628         struct usb_pcwd_private *usb_pcwd = NULL;
629         int pipe, maxp;
630         int retval = -ENOMEM;
631         int got_fw_rev;
632         unsigned char fw_rev_major, fw_rev_minor;
633         char fw_ver_str[20];
634         unsigned char option_switches, dummy;
635
636         cards_found++;
637         if (cards_found > 1) {
638                 pr_err("This driver only supports 1 device\n");
639                 return -ENODEV;
640         }
641
642         /* get the active interface descriptor */
643         iface_desc = interface->cur_altsetting;
644
645         /* check out that we have a HID device */
646         if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
647                 pr_err("The device isn't a Human Interface Device\n");
648                 return -ENODEV;
649         }
650
651         /* check out the endpoint: it has to be Interrupt & IN */
652         endpoint = &iface_desc->endpoint[0].desc;
653
654         if (!usb_endpoint_is_int_in(endpoint)) {
655                 /* we didn't find a Interrupt endpoint with direction IN */
656                 pr_err("Couldn't find an INTR & IN endpoint\n");
657                 return -ENODEV;
658         }
659
660         /* get a handle to the interrupt data pipe */
661         pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
662         maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
663
664         /* allocate memory for our device and initialize it */
665         usb_pcwd = kzalloc(sizeof(struct usb_pcwd_private), GFP_KERNEL);
666         if (usb_pcwd == NULL) {
667                 pr_err("Out of memory\n");
668                 goto error;
669         }
670
671         usb_pcwd_device = usb_pcwd;
672
673         mutex_init(&usb_pcwd->mtx);
674         usb_pcwd->udev = udev;
675         usb_pcwd->interface = interface;
676         usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
677         usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ?
678                                 le16_to_cpu(endpoint->wMaxPacketSize) : 8);
679
680         /* set up the memory buffer's */
681         usb_pcwd->intr_buffer = usb_alloc_coherent(udev, usb_pcwd->intr_size,
682                                         GFP_ATOMIC, &usb_pcwd->intr_dma);
683         if (!usb_pcwd->intr_buffer) {
684                 pr_err("Out of memory\n");
685                 goto error;
686         }
687
688         /* allocate the urb's */
689         usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
690         if (!usb_pcwd->intr_urb) {
691                 pr_err("Out of memory\n");
692                 goto error;
693         }
694
695         /* initialise the intr urb's */
696         usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
697                         usb_pcwd->intr_buffer, usb_pcwd->intr_size,
698                         usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
699         usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
700         usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
701
702         /* register our interrupt URB with the USB system */
703         if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
704                 pr_err("Problem registering interrupt URB\n");
705                 retval = -EIO; /* failure */
706                 goto error;
707         }
708
709         /* The device exists and can be communicated with */
710         usb_pcwd->exists = 1;
711
712         /* disable card */
713         usb_pcwd_stop(usb_pcwd);
714
715         /* Get the Firmware Version */
716         got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION,
717                                                 &fw_rev_major, &fw_rev_minor);
718         if (got_fw_rev)
719                 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
720         else
721                 sprintf(fw_ver_str, "<card no answer>");
722
723         pr_info("Found card (Firmware: %s) with temp option\n", fw_ver_str);
724
725         /* Get switch settings */
726         usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy,
727                                                         &option_switches);
728
729         pr_info("Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
730                 option_switches,
731                 ((option_switches & 0x10) ? "ON" : "OFF"),
732                 ((option_switches & 0x08) ? "ON" : "OFF"));
733
734         /* If heartbeat = 0 then we use the heartbeat from the dip-switches */
735         if (heartbeat == 0)
736                 heartbeat = heartbeat_tbl[(option_switches & 0x07)];
737
738         /* Check that the heartbeat value is within it's range ;
739          * if not reset to the default */
740         if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
741                 usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
742                 pr_info("heartbeat value must be 0<heartbeat<65536, using %d\n",
743                         WATCHDOG_HEARTBEAT);
744         }
745
746         retval = register_reboot_notifier(&usb_pcwd_notifier);
747         if (retval != 0) {
748                 pr_err("cannot register reboot notifier (err=%d)\n", retval);
749                 goto error;
750         }
751
752         retval = misc_register(&usb_pcwd_temperature_miscdev);
753         if (retval != 0) {
754                 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
755                        TEMP_MINOR, retval);
756                 goto err_out_unregister_reboot;
757         }
758
759         retval = misc_register(&usb_pcwd_miscdev);
760         if (retval != 0) {
761                 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
762                        WATCHDOG_MINOR, retval);
763                 goto err_out_misc_deregister;
764         }
765
766         /* we can register the device now, as it is ready */
767         usb_set_intfdata(interface, usb_pcwd);
768
769         pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
770                 heartbeat, nowayout);
771
772         return 0;
773
774 err_out_misc_deregister:
775         misc_deregister(&usb_pcwd_temperature_miscdev);
776 err_out_unregister_reboot:
777         unregister_reboot_notifier(&usb_pcwd_notifier);
778 error:
779         if (usb_pcwd)
780                 usb_pcwd_delete(usb_pcwd);
781         usb_pcwd_device = NULL;
782         return retval;
783 }
784
785
786 /**
787  *      usb_pcwd_disconnect
788  *
789  *      Called by the usb core when the device is removed from the system.
790  *
791  *      This routine guarantees that the driver will not submit any more urbs
792  *      by clearing dev->udev.
793  */
794 static void usb_pcwd_disconnect(struct usb_interface *interface)
795 {
796         struct usb_pcwd_private *usb_pcwd;
797
798         /* prevent races with open() */
799         mutex_lock(&disconnect_mutex);
800
801         usb_pcwd = usb_get_intfdata(interface);
802         usb_set_intfdata(interface, NULL);
803
804         mutex_lock(&usb_pcwd->mtx);
805
806         /* Stop the timer before we leave */
807         if (!nowayout)
808                 usb_pcwd_stop(usb_pcwd);
809
810         /* We should now stop communicating with the USB PCWD device */
811         usb_pcwd->exists = 0;
812
813         /* Deregister */
814         misc_deregister(&usb_pcwd_miscdev);
815         misc_deregister(&usb_pcwd_temperature_miscdev);
816         unregister_reboot_notifier(&usb_pcwd_notifier);
817
818         mutex_unlock(&usb_pcwd->mtx);
819
820         /* Delete the USB PCWD device */
821         usb_pcwd_delete(usb_pcwd);
822
823         cards_found--;
824
825         mutex_unlock(&disconnect_mutex);
826
827         pr_info("USB PC Watchdog disconnected\n");
828 }
829
830 module_usb_driver(usb_pcwd_driver);