Merge branch 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[firefly-linux-kernel-4.4.55.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
48 /* Module and Version Information */
49 #define DRIVER_VERSION "1.02"
50 #define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
51 #define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
52 #define DRIVER_LICENSE "GPL"
53 #define DRIVER_NAME "pcwd_usb"
54
55 MODULE_AUTHOR(DRIVER_AUTHOR);
56 MODULE_DESCRIPTION(DRIVER_DESC);
57 MODULE_LICENSE(DRIVER_LICENSE);
58
59 #define WATCHDOG_HEARTBEAT 0    /* default heartbeat =
60                                                 delay-time from dip-switches */
61 static int heartbeat = WATCHDOG_HEARTBEAT;
62 module_param(heartbeat, int, 0);
63 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. "
64         "(0<heartbeat<65536 or 0=delay-time from dip-switches, default="
65                                 __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
66
67 static bool nowayout = WATCHDOG_NOWAYOUT;
68 module_param(nowayout, bool, 0);
69 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
70                                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
71
72 /* The vendor and product id's for the USB-PC Watchdog card */
73 #define USB_PCWD_VENDOR_ID      0x0c98
74 #define USB_PCWD_PRODUCT_ID     0x1140
75
76 /* table of devices that work with this driver */
77 static struct usb_device_id usb_pcwd_table[] = {
78         { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
79         { }                                     /* Terminating entry */
80 };
81 MODULE_DEVICE_TABLE(usb, usb_pcwd_table);
82
83 /* according to documentation max. time to process a command for the USB
84  * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */
85 #define USB_COMMAND_TIMEOUT     250
86
87 /* Watchdog's internal commands */
88 #define CMD_READ_TEMP                   0x02    /* Read Temperature;
89                                                         Re-trigger Watchdog */
90 #define CMD_TRIGGER                     CMD_READ_TEMP
91 #define CMD_GET_STATUS                  0x04    /* Get Status Information */
92 #define CMD_GET_FIRMWARE_VERSION        0x08    /* Get Firmware Version */
93 #define CMD_GET_DIP_SWITCH_SETTINGS     0x0c    /* Get Dip Switch Settings */
94 #define CMD_READ_WATCHDOG_TIMEOUT       0x18    /* Read Current Watchdog Time */
95 #define CMD_WRITE_WATCHDOG_TIMEOUT      0x19    /* Write Current WatchdogTime */
96 #define CMD_ENABLE_WATCHDOG             0x30    /* Enable / Disable Watchdog */
97 #define CMD_DISABLE_WATCHDOG            CMD_ENABLE_WATCHDOG
98
99 /* Watchdog's Dip Switch heartbeat values */
100 static const int heartbeat_tbl[] = {
101         5,      /* OFF-OFF-OFF  =  5 Sec  */
102         10,     /* OFF-OFF-ON   = 10 Sec  */
103         30,     /* OFF-ON-OFF   = 30 Sec  */
104         60,     /* OFF-ON-ON    =  1 Min  */
105         300,    /* ON-OFF-OFF   =  5 Min  */
106         600,    /* ON-OFF-ON    = 10 Min  */
107         1800,   /* ON-ON-OFF    = 30 Min  */
108         3600,   /* ON-ON-ON     =  1 hour */
109 };
110
111 /* We can only use 1 card due to the /dev/watchdog restriction */
112 static int cards_found;
113
114 /* some internal variables */
115 static unsigned long is_active;
116 static char expect_release;
117
118 /* Structure to hold all of our device specific stuff */
119 struct usb_pcwd_private {
120         /* save off the usb device pointer */
121         struct usb_device       *udev;
122         /* the interface for this device */
123         struct usb_interface    *interface;
124
125         /* the interface number used for cmd's */
126         unsigned int            interface_number;
127
128         /* the buffer to intr data */
129         unsigned char           *intr_buffer;
130         /* the dma address for the intr buffer */
131         dma_addr_t              intr_dma;
132         /* the size of the intr buffer */
133         size_t                  intr_size;
134         /* the urb used for the intr pipe */
135         struct urb              *intr_urb;
136
137         /* The command that is reported back */
138         unsigned char           cmd_command;
139         /* The data MSB that is reported back */
140         unsigned char           cmd_data_msb;
141         /* The data LSB that is reported back */
142         unsigned char           cmd_data_lsb;
143         /* true if we received a report after a command */
144         atomic_t                cmd_received;
145
146         /* Wether or not the device exists */
147         int                     exists;
148         /* locks this structure */
149         struct mutex            mtx;
150 };
151 static struct usb_pcwd_private *usb_pcwd_device;
152
153 /* prevent races between open() and disconnect() */
154 static DEFINE_MUTEX(disconnect_mutex);
155
156 /* local function prototypes */
157 static int usb_pcwd_probe(struct usb_interface *interface,
158                                                 const struct usb_device_id *id);
159 static void usb_pcwd_disconnect(struct usb_interface *interface);
160
161 /* usb specific object needed to register this driver with the usb subsystem */
162 static struct usb_driver usb_pcwd_driver = {
163         .name =         DRIVER_NAME,
164         .probe =        usb_pcwd_probe,
165         .disconnect =   usb_pcwd_disconnect,
166         .id_table =     usb_pcwd_table,
167 };
168
169
170 static void usb_pcwd_intr_done(struct urb *urb)
171 {
172         struct usb_pcwd_private *usb_pcwd =
173                                 (struct usb_pcwd_private *)urb->context;
174         unsigned char *data = usb_pcwd->intr_buffer;
175         struct device *dev = &usb_pcwd->interface->dev;
176         int retval;
177
178         switch (urb->status) {
179         case 0:                 /* success */
180                 break;
181         case -ECONNRESET:       /* unlink */
182         case -ENOENT:
183         case -ESHUTDOWN:
184                 /* this urb is terminated, clean up */
185                 dev_dbg(dev, "%s - urb shutting down with status: %d",
186                         __func__, urb->status);
187                 return;
188         /* -EPIPE:  should clear the halt */
189         default:                /* error */
190                 dev_dbg(dev, "%s - nonzero urb status received: %d",
191                         __func__, urb->status);
192                 goto resubmit;
193         }
194
195         dev_dbg(dev, "received following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
196                 data[0], data[1], data[2]);
197
198         usb_pcwd->cmd_command  = data[0];
199         usb_pcwd->cmd_data_msb = data[1];
200         usb_pcwd->cmd_data_lsb = data[2];
201
202         /* notify anyone waiting that the cmd has finished */
203         atomic_set(&usb_pcwd->cmd_received, 1);
204
205 resubmit:
206         retval = usb_submit_urb(urb, GFP_ATOMIC);
207         if (retval)
208                 pr_err("can't resubmit intr, usb_submit_urb failed with result %d\n",
209                        retval);
210 }
211
212 static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd,
213                 unsigned char cmd, unsigned char *msb, unsigned char *lsb)
214 {
215         int got_response, count;
216         unsigned char *buf;
217
218         /* We will not send any commands if the USB PCWD device does
219          * not exist */
220         if ((!usb_pcwd) || (!usb_pcwd->exists))
221                 return -1;
222
223         buf = kmalloc(6, GFP_KERNEL);
224         if (buf == NULL)
225                 return 0;
226
227         /* The USB PC Watchdog uses a 6 byte report format.
228          * The board currently uses only 3 of the six bytes of the report. */
229         buf[0] = cmd;                   /* Byte 0 = CMD */
230         buf[1] = *msb;                  /* Byte 1 = Data MSB */
231         buf[2] = *lsb;                  /* Byte 2 = Data LSB */
232         buf[3] = buf[4] = buf[5] = 0;   /* All other bytes not used */
233
234         dev_dbg(&usb_pcwd->interface->dev,
235                 "sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
236                 buf[0], buf[1], buf[2]);
237
238         atomic_set(&usb_pcwd->cmd_received, 0);
239
240         if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
241                         HID_REQ_SET_REPORT, HID_DT_REPORT,
242                         0x0200, usb_pcwd->interface_number, buf, 6,
243                         USB_COMMAND_TIMEOUT) != 6) {
244                 dev_dbg(&usb_pcwd->interface->dev,
245                         "usb_pcwd_send_command: error in usb_control_msg for cmd 0x%x 0x%x 0x%x\n",
246                         cmd, *msb, *lsb);
247         }
248         /* wait till the usb card processed the command,
249          * with a max. timeout of USB_COMMAND_TIMEOUT */
250         got_response = 0;
251         for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response);
252                                                                 count++) {
253                 mdelay(1);
254                 if (atomic_read(&usb_pcwd->cmd_received))
255                         got_response = 1;
256         }
257
258         if ((got_response) && (cmd == usb_pcwd->cmd_command)) {
259                 /* read back response */
260                 *msb = usb_pcwd->cmd_data_msb;
261                 *lsb = usb_pcwd->cmd_data_lsb;
262         }
263
264         kfree(buf);
265
266         return got_response;
267 }
268
269 static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd)
270 {
271         unsigned char msb = 0x00;
272         unsigned char lsb = 0x00;
273         int retval;
274
275         /* Enable Watchdog */
276         retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG,
277                                                                 &msb, &lsb);
278
279         if ((retval == 0) || (lsb == 0)) {
280                 pr_err("Card did not acknowledge enable attempt\n");
281                 return -1;
282         }
283
284         return 0;
285 }
286
287 static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd)
288 {
289         unsigned char msb = 0xA5;
290         unsigned char lsb = 0xC3;
291         int retval;
292
293         /* Disable Watchdog */
294         retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG,
295                                                                 &msb, &lsb);
296
297         if ((retval == 0) || (lsb != 0)) {
298                 pr_err("Card did not acknowledge disable attempt\n");
299                 return -1;
300         }
301
302         return 0;
303 }
304
305 static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd)
306 {
307         unsigned char dummy;
308
309         /* Re-trigger Watchdog */
310         usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy);
311
312         return 0;
313 }
314
315 static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t)
316 {
317         unsigned char msb = t / 256;
318         unsigned char lsb = t % 256;
319
320         if ((t < 0x0001) || (t > 0xFFFF))
321                 return -EINVAL;
322
323         /* Write new heartbeat to watchdog */
324         usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb);
325
326         heartbeat = t;
327         return 0;
328 }
329
330 static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd,
331                                                         int *temperature)
332 {
333         unsigned char msb, lsb;
334
335         usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
336
337         /*
338          * Convert celsius to fahrenheit, since this was
339          * the decided 'standard' for this return value.
340          */
341         *temperature = (lsb * 9 / 5) + 32;
342
343         return 0;
344 }
345
346 static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd,
347                                                                 int *time_left)
348 {
349         unsigned char msb, lsb;
350
351         /* Read the time that's left before rebooting */
352         /* Note: if the board is not yet armed then we will read 0xFFFF */
353         usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
354
355         *time_left = (msb << 8) + lsb;
356
357         return 0;
358 }
359
360 /*
361  *      /dev/watchdog handling
362  */
363
364 static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
365                                                 size_t len, loff_t *ppos)
366 {
367         /* See if we got the magic character 'V' and reload the timer */
368         if (len) {
369                 if (!nowayout) {
370                         size_t i;
371
372                         /* note: just in case someone wrote the magic character
373                          * five months ago... */
374                         expect_release = 0;
375
376                         /* scan to see whether or not we got the
377                          * magic character */
378                         for (i = 0; i != len; i++) {
379                                 char c;
380                                 if (get_user(c, data + i))
381                                         return -EFAULT;
382                                 if (c == 'V')
383                                         expect_release = 42;
384                         }
385                 }
386
387                 /* someone wrote to us, we should reload the timer */
388                 usb_pcwd_keepalive(usb_pcwd_device);
389         }
390         return len;
391 }
392
393 static long usb_pcwd_ioctl(struct file *file, unsigned int cmd,
394                                                 unsigned long arg)
395 {
396         void __user *argp = (void __user *)arg;
397         int __user *p = argp;
398         static const struct watchdog_info ident = {
399                 .options =              WDIOF_KEEPALIVEPING |
400                                         WDIOF_SETTIMEOUT |
401                                         WDIOF_MAGICCLOSE,
402                 .firmware_version =     1,
403                 .identity =             DRIVER_NAME,
404         };
405
406         switch (cmd) {
407         case WDIOC_GETSUPPORT:
408                 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
409
410         case WDIOC_GETSTATUS:
411         case WDIOC_GETBOOTSTATUS:
412                 return put_user(0, p);
413
414         case WDIOC_GETTEMP:
415         {
416                 int temperature;
417
418                 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
419                         return -EFAULT;
420
421                 return put_user(temperature, p);
422         }
423
424         case WDIOC_SETOPTIONS:
425         {
426                 int new_options, retval = -EINVAL;
427
428                 if (get_user(new_options, p))
429                         return -EFAULT;
430
431                 if (new_options & WDIOS_DISABLECARD) {
432                         usb_pcwd_stop(usb_pcwd_device);
433                         retval = 0;
434                 }
435
436                 if (new_options & WDIOS_ENABLECARD) {
437                         usb_pcwd_start(usb_pcwd_device);
438                         retval = 0;
439                 }
440
441                 return retval;
442         }
443
444         case WDIOC_KEEPALIVE:
445                 usb_pcwd_keepalive(usb_pcwd_device);
446                 return 0;
447
448         case WDIOC_SETTIMEOUT:
449         {
450                 int new_heartbeat;
451
452                 if (get_user(new_heartbeat, p))
453                         return -EFAULT;
454
455                 if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
456                         return -EINVAL;
457
458                 usb_pcwd_keepalive(usb_pcwd_device);
459                 /* Fall */
460         }
461
462         case WDIOC_GETTIMEOUT:
463                 return put_user(heartbeat, p);
464
465         case WDIOC_GETTIMELEFT:
466         {
467                 int time_left;
468
469                 if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left))
470                         return -EFAULT;
471
472                 return put_user(time_left, p);
473         }
474
475         default:
476                 return -ENOTTY;
477         }
478 }
479
480 static int usb_pcwd_open(struct inode *inode, struct file *file)
481 {
482         /* /dev/watchdog can only be opened once */
483         if (test_and_set_bit(0, &is_active))
484                 return -EBUSY;
485
486         /* Activate */
487         usb_pcwd_start(usb_pcwd_device);
488         usb_pcwd_keepalive(usb_pcwd_device);
489         return nonseekable_open(inode, file);
490 }
491
492 static int usb_pcwd_release(struct inode *inode, struct file *file)
493 {
494         /*
495          *      Shut off the timer.
496          */
497         if (expect_release == 42) {
498                 usb_pcwd_stop(usb_pcwd_device);
499         } else {
500                 pr_crit("Unexpected close, not stopping watchdog!\n");
501                 usb_pcwd_keepalive(usb_pcwd_device);
502         }
503         expect_release = 0;
504         clear_bit(0, &is_active);
505         return 0;
506 }
507
508 /*
509  *      /dev/temperature handling
510  */
511
512 static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
513                                 size_t len, loff_t *ppos)
514 {
515         int temperature;
516
517         if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
518                 return -EFAULT;
519
520         if (copy_to_user(data, &temperature, 1))
521                 return -EFAULT;
522
523         return 1;
524 }
525
526 static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
527 {
528         return nonseekable_open(inode, file);
529 }
530
531 static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
532 {
533         return 0;
534 }
535
536 /*
537  *      Notify system
538  */
539
540 static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code,
541                                                                 void *unused)
542 {
543         if (code == SYS_DOWN || code == SYS_HALT)
544                 usb_pcwd_stop(usb_pcwd_device); /* Turn the WDT off */
545
546         return NOTIFY_DONE;
547 }
548
549 /*
550  *      Kernel Interfaces
551  */
552
553 static const struct file_operations usb_pcwd_fops = {
554         .owner =        THIS_MODULE,
555         .llseek =       no_llseek,
556         .write =        usb_pcwd_write,
557         .unlocked_ioctl = usb_pcwd_ioctl,
558         .open =         usb_pcwd_open,
559         .release =      usb_pcwd_release,
560 };
561
562 static struct miscdevice usb_pcwd_miscdev = {
563         .minor =        WATCHDOG_MINOR,
564         .name =         "watchdog",
565         .fops =         &usb_pcwd_fops,
566 };
567
568 static const struct file_operations usb_pcwd_temperature_fops = {
569         .owner =        THIS_MODULE,
570         .llseek =       no_llseek,
571         .read =         usb_pcwd_temperature_read,
572         .open =         usb_pcwd_temperature_open,
573         .release =      usb_pcwd_temperature_release,
574 };
575
576 static struct miscdevice usb_pcwd_temperature_miscdev = {
577         .minor =        TEMP_MINOR,
578         .name =         "temperature",
579         .fops =         &usb_pcwd_temperature_fops,
580 };
581
582 static struct notifier_block usb_pcwd_notifier = {
583         .notifier_call =        usb_pcwd_notify_sys,
584 };
585
586 /**
587  *      usb_pcwd_delete
588  */
589 static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd)
590 {
591         usb_free_urb(usb_pcwd->intr_urb);
592         if (usb_pcwd->intr_buffer != NULL)
593                 usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size,
594                                   usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
595         kfree(usb_pcwd);
596 }
597
598 /**
599  *      usb_pcwd_probe
600  *
601  *      Called by the usb core when a new device is connected that it thinks
602  *      this driver might be interested in.
603  */
604 static int usb_pcwd_probe(struct usb_interface *interface,
605                                                 const struct usb_device_id *id)
606 {
607         struct usb_device *udev = interface_to_usbdev(interface);
608         struct usb_host_interface *iface_desc;
609         struct usb_endpoint_descriptor *endpoint;
610         struct usb_pcwd_private *usb_pcwd = NULL;
611         int pipe, maxp;
612         int retval = -ENOMEM;
613         int got_fw_rev;
614         unsigned char fw_rev_major, fw_rev_minor;
615         char fw_ver_str[20];
616         unsigned char option_switches, dummy;
617
618         cards_found++;
619         if (cards_found > 1) {
620                 pr_err("This driver only supports 1 device\n");
621                 return -ENODEV;
622         }
623
624         /* get the active interface descriptor */
625         iface_desc = interface->cur_altsetting;
626
627         /* check out that we have a HID device */
628         if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
629                 pr_err("The device isn't a Human Interface Device\n");
630                 return -ENODEV;
631         }
632
633         /* check out the endpoint: it has to be Interrupt & IN */
634         endpoint = &iface_desc->endpoint[0].desc;
635
636         if (!usb_endpoint_is_int_in(endpoint)) {
637                 /* we didn't find a Interrupt endpoint with direction IN */
638                 pr_err("Couldn't find an INTR & IN endpoint\n");
639                 return -ENODEV;
640         }
641
642         /* get a handle to the interrupt data pipe */
643         pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
644         maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
645
646         /* allocate memory for our device and initialize it */
647         usb_pcwd = kzalloc(sizeof(struct usb_pcwd_private), GFP_KERNEL);
648         if (usb_pcwd == NULL)
649                 goto error;
650
651         usb_pcwd_device = usb_pcwd;
652
653         mutex_init(&usb_pcwd->mtx);
654         usb_pcwd->udev = udev;
655         usb_pcwd->interface = interface;
656         usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
657         usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ?
658                                 le16_to_cpu(endpoint->wMaxPacketSize) : 8);
659
660         /* set up the memory buffer's */
661         usb_pcwd->intr_buffer = usb_alloc_coherent(udev, usb_pcwd->intr_size,
662                                         GFP_ATOMIC, &usb_pcwd->intr_dma);
663         if (!usb_pcwd->intr_buffer) {
664                 pr_err("Out of memory\n");
665                 goto error;
666         }
667
668         /* allocate the urb's */
669         usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
670         if (!usb_pcwd->intr_urb) {
671                 pr_err("Out of memory\n");
672                 goto error;
673         }
674
675         /* initialise the intr urb's */
676         usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
677                         usb_pcwd->intr_buffer, usb_pcwd->intr_size,
678                         usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
679         usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
680         usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
681
682         /* register our interrupt URB with the USB system */
683         if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
684                 pr_err("Problem registering interrupt URB\n");
685                 retval = -EIO; /* failure */
686                 goto error;
687         }
688
689         /* The device exists and can be communicated with */
690         usb_pcwd->exists = 1;
691
692         /* disable card */
693         usb_pcwd_stop(usb_pcwd);
694
695         /* Get the Firmware Version */
696         got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION,
697                                                 &fw_rev_major, &fw_rev_minor);
698         if (got_fw_rev)
699                 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
700         else
701                 sprintf(fw_ver_str, "<card no answer>");
702
703         pr_info("Found card (Firmware: %s) with temp option\n", fw_ver_str);
704
705         /* Get switch settings */
706         usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy,
707                                                         &option_switches);
708
709         pr_info("Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
710                 option_switches,
711                 ((option_switches & 0x10) ? "ON" : "OFF"),
712                 ((option_switches & 0x08) ? "ON" : "OFF"));
713
714         /* If heartbeat = 0 then we use the heartbeat from the dip-switches */
715         if (heartbeat == 0)
716                 heartbeat = heartbeat_tbl[(option_switches & 0x07)];
717
718         /* Check that the heartbeat value is within it's range ;
719          * if not reset to the default */
720         if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
721                 usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
722                 pr_info("heartbeat value must be 0<heartbeat<65536, using %d\n",
723                         WATCHDOG_HEARTBEAT);
724         }
725
726         retval = register_reboot_notifier(&usb_pcwd_notifier);
727         if (retval != 0) {
728                 pr_err("cannot register reboot notifier (err=%d)\n", retval);
729                 goto error;
730         }
731
732         retval = misc_register(&usb_pcwd_temperature_miscdev);
733         if (retval != 0) {
734                 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
735                        TEMP_MINOR, retval);
736                 goto err_out_unregister_reboot;
737         }
738
739         retval = misc_register(&usb_pcwd_miscdev);
740         if (retval != 0) {
741                 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
742                        WATCHDOG_MINOR, retval);
743                 goto err_out_misc_deregister;
744         }
745
746         /* we can register the device now, as it is ready */
747         usb_set_intfdata(interface, usb_pcwd);
748
749         pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
750                 heartbeat, nowayout);
751
752         return 0;
753
754 err_out_misc_deregister:
755         misc_deregister(&usb_pcwd_temperature_miscdev);
756 err_out_unregister_reboot:
757         unregister_reboot_notifier(&usb_pcwd_notifier);
758 error:
759         if (usb_pcwd)
760                 usb_pcwd_delete(usb_pcwd);
761         usb_pcwd_device = NULL;
762         return retval;
763 }
764
765
766 /**
767  *      usb_pcwd_disconnect
768  *
769  *      Called by the usb core when the device is removed from the system.
770  *
771  *      This routine guarantees that the driver will not submit any more urbs
772  *      by clearing dev->udev.
773  */
774 static void usb_pcwd_disconnect(struct usb_interface *interface)
775 {
776         struct usb_pcwd_private *usb_pcwd;
777
778         /* prevent races with open() */
779         mutex_lock(&disconnect_mutex);
780
781         usb_pcwd = usb_get_intfdata(interface);
782         usb_set_intfdata(interface, NULL);
783
784         mutex_lock(&usb_pcwd->mtx);
785
786         /* Stop the timer before we leave */
787         if (!nowayout)
788                 usb_pcwd_stop(usb_pcwd);
789
790         /* We should now stop communicating with the USB PCWD device */
791         usb_pcwd->exists = 0;
792
793         /* Deregister */
794         misc_deregister(&usb_pcwd_miscdev);
795         misc_deregister(&usb_pcwd_temperature_miscdev);
796         unregister_reboot_notifier(&usb_pcwd_notifier);
797
798         mutex_unlock(&usb_pcwd->mtx);
799
800         /* Delete the USB PCWD device */
801         usb_pcwd_delete(usb_pcwd);
802
803         cards_found--;
804
805         mutex_unlock(&disconnect_mutex);
806
807         pr_info("USB PC Watchdog disconnected\n");
808 }
809
810 module_usb_driver(usb_pcwd_driver);