V4L/DVB (10013): Convert all sensors to use the unified write sensor function
[linux-2.6] / 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 #include <linux/module.h>       /* For module specific items */
28 #include <linux/moduleparam.h>  /* For new moduleparam's */
29 #include <linux/types.h>        /* For standard types (like size_t) */
30 #include <linux/errno.h>        /* For the -ENODEV/... values */
31 #include <linux/kernel.h>       /* For printk/panic/... */
32 #include <linux/delay.h>        /* For mdelay function */
33 #include <linux/miscdevice.h>   /* For MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR) */
34 #include <linux/watchdog.h>     /* For the watchdog specific items */
35 #include <linux/notifier.h>     /* For notifier support */
36 #include <linux/reboot.h>       /* For reboot_notifier stuff */
37 #include <linux/init.h>         /* For __init/__exit/... */
38 #include <linux/fs.h>           /* For file operations */
39 #include <linux/usb.h>          /* For USB functions */
40 #include <linux/slab.h>         /* For kmalloc, ... */
41 #include <linux/mutex.h>        /* For mutex locking */
42 #include <linux/hid.h>          /* For HID_REQ_SET_REPORT & HID_DT_REPORT */
43 #include <linux/uaccess.h>      /* For copy_to_user/put_user/... */
44
45
46 #ifdef CONFIG_USB_DEBUG
47         static int debug = 1;
48 #else
49         static int debug;
50 #endif
51
52 /* Use our own dbg macro */
53 #undef dbg
54 #define dbg(format, arg...) do { if (debug) printk(KERN_DEBUG PFX format "\n" , ## arg); } while (0)
55
56
57 /* Module and Version Information */
58 #define DRIVER_VERSION "1.02"
59 #define DRIVER_DATE "21 Jan 2007"
60 #define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
61 #define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
62 #define DRIVER_LICENSE "GPL"
63 #define DRIVER_NAME "pcwd_usb"
64 #define PFX DRIVER_NAME ": "
65
66 MODULE_AUTHOR(DRIVER_AUTHOR);
67 MODULE_DESCRIPTION(DRIVER_DESC);
68 MODULE_LICENSE(DRIVER_LICENSE);
69 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
70 MODULE_ALIAS_MISCDEV(TEMP_MINOR);
71
72 /* Module Parameters */
73 module_param(debug, int, 0);
74 MODULE_PARM_DESC(debug, "Debug enabled or not");
75
76 #define WATCHDOG_HEARTBEAT 0    /* default heartbeat = delay-time from dip-switches */
77 static int heartbeat = WATCHDOG_HEARTBEAT;
78 module_param(heartbeat, int, 0);
79 MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. (0<heartbeat<65536 or 0=delay-time from dip-switches, default=" __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
80
81 static int nowayout = WATCHDOG_NOWAYOUT;
82 module_param(nowayout, int, 0);
83 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
84
85 /* The vendor and product id's for the USB-PC Watchdog card */
86 #define USB_PCWD_VENDOR_ID      0x0c98
87 #define USB_PCWD_PRODUCT_ID     0x1140
88
89 /* table of devices that work with this driver */
90 static struct usb_device_id usb_pcwd_table[] = {
91         { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
92         { }                                     /* Terminating entry */
93 };
94 MODULE_DEVICE_TABLE (usb, usb_pcwd_table);
95
96 /* according to documentation max. time to process a command for the USB
97  * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */
98 #define USB_COMMAND_TIMEOUT     250
99
100 /* Watchdog's internal commands */
101 #define CMD_READ_TEMP                   0x02    /* Read Temperature; Re-trigger Watchdog */
102 #define CMD_TRIGGER                     CMD_READ_TEMP
103 #define CMD_GET_STATUS                  0x04    /* Get Status Information */
104 #define CMD_GET_FIRMWARE_VERSION        0x08    /* Get Firmware Version */
105 #define CMD_GET_DIP_SWITCH_SETTINGS     0x0c    /* Get Dip Switch Settings */
106 #define CMD_READ_WATCHDOG_TIMEOUT       0x18    /* Read Current Watchdog Time */
107 #define CMD_WRITE_WATCHDOG_TIMEOUT      0x19    /* Write Current Watchdog Time */
108 #define CMD_ENABLE_WATCHDOG             0x30    /* Enable / Disable Watchdog */
109 #define CMD_DISABLE_WATCHDOG            CMD_ENABLE_WATCHDOG
110
111 /* Watchdog's Dip Switch heartbeat values */
112 static const int heartbeat_tbl[] = {
113         5,      /* OFF-OFF-OFF  =  5 Sec  */
114         10,     /* OFF-OFF-ON   = 10 Sec  */
115         30,     /* OFF-ON-OFF   = 30 Sec  */
116         60,     /* OFF-ON-ON    =  1 Min  */
117         300,    /* ON-OFF-OFF   =  5 Min  */
118         600,    /* ON-OFF-ON    = 10 Min  */
119         1800,   /* ON-ON-OFF    = 30 Min  */
120         3600,   /* ON-ON-ON     =  1 hour */
121 };
122
123 /* We can only use 1 card due to the /dev/watchdog restriction */
124 static int cards_found;
125
126 /* some internal variables */
127 static unsigned long is_active;
128 static char expect_release;
129
130 /* Structure to hold all of our device specific stuff */
131 struct usb_pcwd_private {
132         struct usb_device       *udev;                  /* save off the usb device pointer */
133         struct usb_interface    *interface;             /* the interface for this device */
134
135         unsigned int            interface_number;       /* the interface number used for cmd's */
136
137         unsigned char           *intr_buffer;           /* the buffer to intr data */
138         dma_addr_t              intr_dma;               /* the dma address for the intr buffer */
139         size_t                  intr_size;              /* the size of the intr buffer */
140         struct urb              *intr_urb;              /* the urb used for the intr pipe */
141
142         unsigned char           cmd_command;            /* The command that is reported back */
143         unsigned char           cmd_data_msb;           /* The data MSB that is reported back */
144         unsigned char           cmd_data_lsb;           /* The data LSB that is reported back */
145         atomic_t                cmd_received;           /* true if we received a report after a command */
146
147         int                     exists;                 /* Wether or not the device exists */
148         struct mutex            mtx;                    /* locks this structure */
149 };
150 static struct usb_pcwd_private *usb_pcwd_device;
151
152 /* prevent races between open() and disconnect() */
153 static DEFINE_MUTEX(disconnect_mutex);
154
155 /* local function prototypes */
156 static int usb_pcwd_probe(struct usb_interface *interface, const struct usb_device_id *id);
157 static void usb_pcwd_disconnect(struct usb_interface *interface);
158
159 /* usb specific object needed to register this driver with the usb subsystem */
160 static struct usb_driver usb_pcwd_driver = {
161         .name =         DRIVER_NAME,
162         .probe =        usb_pcwd_probe,
163         .disconnect =   usb_pcwd_disconnect,
164         .id_table =     usb_pcwd_table,
165 };
166
167
168 static void usb_pcwd_intr_done(struct urb *urb)
169 {
170         struct usb_pcwd_private *usb_pcwd = (struct usb_pcwd_private *)urb->context;
171         unsigned char *data = usb_pcwd->intr_buffer;
172         int retval;
173
174         switch (urb->status) {
175         case 0:                 /* success */
176                 break;
177         case -ECONNRESET:       /* unlink */
178         case -ENOENT:
179         case -ESHUTDOWN:
180                 /* this urb is terminated, clean up */
181                 dbg("%s - urb shutting down with status: %d", __func__, urb->status);
182                 return;
183         /* -EPIPE:  should clear the halt */
184         default:                /* error */
185                 dbg("%s - nonzero urb status received: %d", __func__, urb->status);
186                 goto resubmit;
187         }
188
189         dbg("received following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
190                 data[0], data[1], data[2]);
191
192         usb_pcwd->cmd_command  = data[0];
193         usb_pcwd->cmd_data_msb = data[1];
194         usb_pcwd->cmd_data_lsb = data[2];
195
196         /* notify anyone waiting that the cmd has finished */
197         atomic_set(&usb_pcwd->cmd_received, 1);
198
199 resubmit:
200         retval = usb_submit_urb(urb, GFP_ATOMIC);
201         if (retval)
202                 printk(KERN_ERR PFX "can't resubmit intr, usb_submit_urb failed with result %d\n",
203                         retval);
204 }
205
206 static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd, unsigned char cmd,
207         unsigned char *msb, unsigned char *lsb)
208 {
209         int got_response, count;
210         unsigned char buf[6];
211
212         /* We will not send any commands if the USB PCWD device does not exist */
213         if ((!usb_pcwd) || (!usb_pcwd->exists))
214                 return -1;
215
216         /* The USB PC Watchdog uses a 6 byte report format. The board currently uses
217          * only 3 of the six bytes of the report. */
218         buf[0] = cmd;                   /* Byte 0 = CMD */
219         buf[1] = *msb;                  /* Byte 1 = Data MSB */
220         buf[2] = *lsb;                  /* Byte 2 = Data LSB */
221         buf[3] = buf[4] = buf[5] = 0;   /* All other bytes not used */
222
223         dbg("sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
224                 buf[0], buf[1], buf[2]);
225
226         atomic_set(&usb_pcwd->cmd_received, 0);
227
228         if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
229                         HID_REQ_SET_REPORT, HID_DT_REPORT,
230                         0x0200, usb_pcwd->interface_number, buf, sizeof(buf),
231                         USB_COMMAND_TIMEOUT) != sizeof(buf)) {
232                 dbg("usb_pcwd_send_command: error in usb_control_msg for cmd 0x%x 0x%x 0x%x\n", cmd, *msb, *lsb);
233         }
234         /* wait till the usb card processed the command,
235          * with a max. timeout of USB_COMMAND_TIMEOUT */
236         got_response = 0;
237         for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response); count++) {
238                 mdelay(1);
239                 if (atomic_read(&usb_pcwd->cmd_received))
240                         got_response = 1;
241         }
242
243         if ((got_response) && (cmd == usb_pcwd->cmd_command)) {
244                 /* read back response */
245                 *msb = usb_pcwd->cmd_data_msb;
246                 *lsb = usb_pcwd->cmd_data_lsb;
247         }
248
249         return got_response;
250 }
251
252 static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd)
253 {
254         unsigned char msb = 0x00;
255         unsigned char lsb = 0x00;
256         int retval;
257
258         /* Enable Watchdog */
259         retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG, &msb, &lsb);
260
261         if ((retval == 0) || (lsb == 0)) {
262                 printk(KERN_ERR PFX "Card did not acknowledge enable attempt\n");
263                 return -1;
264         }
265
266         return 0;
267 }
268
269 static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd)
270 {
271         unsigned char msb = 0xA5;
272         unsigned char lsb = 0xC3;
273         int retval;
274
275         /* Disable Watchdog */
276         retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG, &msb, &lsb);
277
278         if ((retval == 0) || (lsb != 0)) {
279                 printk(KERN_ERR PFX "Card did not acknowledge disable attempt\n");
280                 return -1;
281         }
282
283         return 0;
284 }
285
286 static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd)
287 {
288         unsigned char dummy;
289
290         /* Re-trigger Watchdog */
291         usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy);
292
293         return 0;
294 }
295
296 static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t)
297 {
298         unsigned char msb = t / 256;
299         unsigned char lsb = t % 256;
300
301         if ((t < 0x0001) || (t > 0xFFFF))
302                 return -EINVAL;
303
304         /* Write new heartbeat to watchdog */
305         usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb);
306
307         heartbeat = t;
308         return 0;
309 }
310
311 static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd, int *temperature)
312 {
313         unsigned char msb, lsb;
314
315         usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
316
317         /*
318          * Convert celsius to fahrenheit, since this was
319          * the decided 'standard' for this return value.
320          */
321         *temperature = (lsb * 9 / 5) + 32;
322
323         return 0;
324 }
325
326 static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd, int *time_left)
327 {
328         unsigned char msb, lsb;
329
330         /* Read the time that's left before rebooting */
331         /* Note: if the board is not yet armed then we will read 0xFFFF */
332         usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
333
334         *time_left = (msb << 8) + lsb;
335
336         return 0;
337 }
338
339 /*
340  *      /dev/watchdog handling
341  */
342
343 static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
344                               size_t len, loff_t *ppos)
345 {
346         /* See if we got the magic character 'V' and reload the timer */
347         if (len) {
348                 if (!nowayout) {
349                         size_t i;
350
351                         /* note: just in case someone wrote the magic character
352                          * five months ago... */
353                         expect_release = 0;
354
355                         /* scan to see whether or not we got the magic character */
356                         for (i = 0; i != len; i++) {
357                                 char c;
358                                 if (get_user(c, data + i))
359                                         return -EFAULT;
360                                 if (c == 'V')
361                                         expect_release = 42;
362                         }
363                 }
364
365                 /* someone wrote to us, we should reload the timer */
366                 usb_pcwd_keepalive(usb_pcwd_device);
367         }
368         return len;
369 }
370
371 static long usb_pcwd_ioctl(struct file *file, unsigned int cmd,
372                                                 unsigned long arg)
373 {
374         void __user *argp = (void __user *)arg;
375         int __user *p = argp;
376         static struct watchdog_info ident = {
377                 .options =              WDIOF_KEEPALIVEPING |
378                                         WDIOF_SETTIMEOUT |
379                                         WDIOF_MAGICCLOSE,
380                 .firmware_version =     1,
381                 .identity =             DRIVER_NAME,
382         };
383
384         switch (cmd) {
385         case WDIOC_GETSUPPORT:
386                 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
387
388         case WDIOC_GETSTATUS:
389         case WDIOC_GETBOOTSTATUS:
390                 return put_user(0, p);
391
392         case WDIOC_GETTEMP:
393         {
394                 int temperature;
395
396                 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
397                         return -EFAULT;
398
399                 return put_user(temperature, p);
400         }
401
402         case WDIOC_SETOPTIONS:
403         {
404                 int new_options, retval = -EINVAL;
405
406                 if (get_user(new_options, p))
407                         return -EFAULT;
408
409                 if (new_options & WDIOS_DISABLECARD) {
410                         usb_pcwd_stop(usb_pcwd_device);
411                         retval = 0;
412                 }
413
414                 if (new_options & WDIOS_ENABLECARD) {
415                         usb_pcwd_start(usb_pcwd_device);
416                         retval = 0;
417                 }
418
419                 return retval;
420         }
421
422         case WDIOC_KEEPALIVE:
423                 usb_pcwd_keepalive(usb_pcwd_device);
424                 return 0;
425
426         case WDIOC_SETTIMEOUT:
427         {
428                 int new_heartbeat;
429
430                 if (get_user(new_heartbeat, p))
431                         return -EFAULT;
432
433                 if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
434                     return -EINVAL;
435
436                 usb_pcwd_keepalive(usb_pcwd_device);
437                 /* Fall */
438         }
439
440         case WDIOC_GETTIMEOUT:
441                 return put_user(heartbeat, p);
442
443         case WDIOC_GETTIMELEFT:
444         {
445                 int time_left;
446
447                 if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left))
448                         return -EFAULT;
449
450                 return put_user(time_left, p);
451         }
452
453         default:
454                 return -ENOTTY;
455         }
456 }
457
458 static int usb_pcwd_open(struct inode *inode, struct file *file)
459 {
460         /* /dev/watchdog can only be opened once */
461         if (test_and_set_bit(0, &is_active))
462                 return -EBUSY;
463
464         /* Activate */
465         usb_pcwd_start(usb_pcwd_device);
466         usb_pcwd_keepalive(usb_pcwd_device);
467         return nonseekable_open(inode, file);
468 }
469
470 static int usb_pcwd_release(struct inode *inode, struct file *file)
471 {
472         /*
473          *      Shut off the timer.
474          */
475         if (expect_release == 42) {
476                 usb_pcwd_stop(usb_pcwd_device);
477         } else {
478                 printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n");
479                 usb_pcwd_keepalive(usb_pcwd_device);
480         }
481         expect_release = 0;
482         clear_bit(0, &is_active);
483         return 0;
484 }
485
486 /*
487  *      /dev/temperature handling
488  */
489
490 static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
491                                 size_t len, loff_t *ppos)
492 {
493         int temperature;
494
495         if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
496                 return -EFAULT;
497
498         if (copy_to_user(data, &temperature, 1))
499                 return -EFAULT;
500
501         return 1;
502 }
503
504 static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
505 {
506         return nonseekable_open(inode, file);
507 }
508
509 static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
510 {
511         return 0;
512 }
513
514 /*
515  *      Notify system
516  */
517
518 static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code, void *unused)
519 {
520         if (code == SYS_DOWN || code == SYS_HALT)
521                 usb_pcwd_stop(usb_pcwd_device); /* Turn the WDT off */
522
523         return NOTIFY_DONE;
524 }
525
526 /*
527  *      Kernel Interfaces
528  */
529
530 static const struct file_operations usb_pcwd_fops = {
531         .owner =        THIS_MODULE,
532         .llseek =       no_llseek,
533         .write =        usb_pcwd_write,
534         .unlocked_ioctl = usb_pcwd_ioctl,
535         .open =         usb_pcwd_open,
536         .release =      usb_pcwd_release,
537 };
538
539 static struct miscdevice usb_pcwd_miscdev = {
540         .minor =        WATCHDOG_MINOR,
541         .name =         "watchdog",
542         .fops =         &usb_pcwd_fops,
543 };
544
545 static const struct file_operations usb_pcwd_temperature_fops = {
546         .owner =        THIS_MODULE,
547         .llseek =       no_llseek,
548         .read =         usb_pcwd_temperature_read,
549         .open =         usb_pcwd_temperature_open,
550         .release =      usb_pcwd_temperature_release,
551 };
552
553 static struct miscdevice usb_pcwd_temperature_miscdev = {
554         .minor =        TEMP_MINOR,
555         .name =         "temperature",
556         .fops =         &usb_pcwd_temperature_fops,
557 };
558
559 static struct notifier_block usb_pcwd_notifier = {
560         .notifier_call =        usb_pcwd_notify_sys,
561 };
562
563 /**
564  *      usb_pcwd_delete
565  */
566 static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd)
567 {
568         usb_free_urb(usb_pcwd->intr_urb);
569         if (usb_pcwd->intr_buffer != NULL)
570                 usb_buffer_free(usb_pcwd->udev, usb_pcwd->intr_size,
571                                 usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
572         kfree(usb_pcwd);
573 }
574
575 /**
576  *      usb_pcwd_probe
577  *
578  *      Called by the usb core when a new device is connected that it thinks
579  *      this driver might be interested in.
580  */
581 static int usb_pcwd_probe(struct usb_interface *interface, const struct usb_device_id *id)
582 {
583         struct usb_device *udev = interface_to_usbdev(interface);
584         struct usb_host_interface *iface_desc;
585         struct usb_endpoint_descriptor *endpoint;
586         struct usb_pcwd_private *usb_pcwd = NULL;
587         int pipe, maxp;
588         int retval = -ENOMEM;
589         int got_fw_rev;
590         unsigned char fw_rev_major, fw_rev_minor;
591         char fw_ver_str[20];
592         unsigned char option_switches, dummy;
593
594         cards_found++;
595         if (cards_found > 1) {
596                 printk(KERN_ERR PFX "This driver only supports 1 device\n");
597                 return -ENODEV;
598         }
599
600         /* get the active interface descriptor */
601         iface_desc = interface->cur_altsetting;
602
603         /* check out that we have a HID device */
604         if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
605                 printk(KERN_ERR PFX "The device isn't a Human Interface Device\n");
606                 return -ENODEV;
607         }
608
609         /* check out the endpoint: it has to be Interrupt & IN */
610         endpoint = &iface_desc->endpoint[0].desc;
611
612         if (!((endpoint->bEndpointAddress & USB_DIR_IN) &&
613              ((endpoint->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK)
614                                 == USB_ENDPOINT_XFER_INT))) {
615                 /* we didn't find a Interrupt endpoint with direction IN */
616                 printk(KERN_ERR PFX "Couldn't find an INTR & IN endpoint\n");
617                 return -ENODEV;
618         }
619
620         /* get a handle to the interrupt data pipe */
621         pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
622         maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
623
624         /* allocate memory for our device and initialize it */
625         usb_pcwd = kzalloc(sizeof(struct usb_pcwd_private), GFP_KERNEL);
626         if (usb_pcwd == NULL) {
627                 printk(KERN_ERR PFX "Out of memory\n");
628                 goto error;
629         }
630
631         usb_pcwd_device = usb_pcwd;
632
633         mutex_init(&usb_pcwd->mtx);
634         usb_pcwd->udev = udev;
635         usb_pcwd->interface = interface;
636         usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
637         usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ? le16_to_cpu(endpoint->wMaxPacketSize) : 8);
638
639         /* set up the memory buffer's */
640         usb_pcwd->intr_buffer = usb_buffer_alloc(udev, usb_pcwd->intr_size, GFP_ATOMIC, &usb_pcwd->intr_dma);
641         if (!usb_pcwd->intr_buffer) {
642                 printk(KERN_ERR PFX "Out of memory\n");
643                 goto error;
644         }
645
646         /* allocate the urb's */
647         usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
648         if (!usb_pcwd->intr_urb) {
649                 printk(KERN_ERR PFX "Out of memory\n");
650                 goto error;
651         }
652
653         /* initialise the intr urb's */
654         usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
655                         usb_pcwd->intr_buffer, usb_pcwd->intr_size,
656                         usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
657         usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
658         usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
659
660         /* register our interrupt URB with the USB system */
661         if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
662                 printk(KERN_ERR PFX "Problem registering interrupt URB\n");
663                 retval = -EIO; /* failure */
664                 goto error;
665         }
666
667         /* The device exists and can be communicated with */
668         usb_pcwd->exists = 1;
669
670         /* disable card */
671         usb_pcwd_stop(usb_pcwd);
672
673         /* Get the Firmware Version */
674         got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION, &fw_rev_major, &fw_rev_minor);
675         if (got_fw_rev)
676                 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
677         else
678                 sprintf(fw_ver_str, "<card no answer>");
679
680         printk(KERN_INFO PFX "Found card (Firmware: %s) with temp option\n",
681                 fw_ver_str);
682
683         /* Get switch settings */
684         usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy, &option_switches);
685
686         printk(KERN_INFO PFX "Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
687                 option_switches,
688                 ((option_switches & 0x10) ? "ON" : "OFF"),
689                 ((option_switches & 0x08) ? "ON" : "OFF"));
690
691         /* If heartbeat = 0 then we use the heartbeat from the dip-switches */
692         if (heartbeat == 0)
693                 heartbeat = heartbeat_tbl[(option_switches & 0x07)];
694
695         /* Check that the heartbeat value is within it's range ; if not reset to the default */
696         if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
697                 usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
698                 printk(KERN_INFO PFX "heartbeat value must be 0<heartbeat<65536, using %d\n",
699                         WATCHDOG_HEARTBEAT);
700         }
701
702         retval = register_reboot_notifier(&usb_pcwd_notifier);
703         if (retval != 0) {
704                 printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n",
705                         retval);
706                 goto error;
707         }
708
709         retval = misc_register(&usb_pcwd_temperature_miscdev);
710         if (retval != 0) {
711                 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
712                         TEMP_MINOR, retval);
713                 goto err_out_unregister_reboot;
714         }
715
716         retval = misc_register(&usb_pcwd_miscdev);
717         if (retval != 0) {
718                 printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n",
719                         WATCHDOG_MINOR, retval);
720                 goto err_out_misc_deregister;
721         }
722
723         /* we can register the device now, as it is ready */
724         usb_set_intfdata(interface, usb_pcwd);
725
726         printk(KERN_INFO PFX "initialized. heartbeat=%d sec (nowayout=%d)\n",
727                 heartbeat, nowayout);
728
729         return 0;
730
731 err_out_misc_deregister:
732         misc_deregister(&usb_pcwd_temperature_miscdev);
733 err_out_unregister_reboot:
734         unregister_reboot_notifier(&usb_pcwd_notifier);
735 error:
736         if (usb_pcwd)
737                 usb_pcwd_delete(usb_pcwd);
738         usb_pcwd_device = NULL;
739         return retval;
740 }
741
742
743 /**
744  *      usb_pcwd_disconnect
745  *
746  *      Called by the usb core when the device is removed from the system.
747  *
748  *      This routine guarantees that the driver will not submit any more urbs
749  *      by clearing dev->udev.
750  */
751 static void usb_pcwd_disconnect(struct usb_interface *interface)
752 {
753         struct usb_pcwd_private *usb_pcwd;
754
755         /* prevent races with open() */
756         mutex_lock(&disconnect_mutex);
757
758         usb_pcwd = usb_get_intfdata(interface);
759         usb_set_intfdata(interface, NULL);
760
761         mutex_lock(&usb_pcwd->mtx);
762
763         /* Stop the timer before we leave */
764         if (!nowayout)
765                 usb_pcwd_stop(usb_pcwd);
766
767         /* We should now stop communicating with the USB PCWD device */
768         usb_pcwd->exists = 0;
769
770         /* Deregister */
771         misc_deregister(&usb_pcwd_miscdev);
772         misc_deregister(&usb_pcwd_temperature_miscdev);
773         unregister_reboot_notifier(&usb_pcwd_notifier);
774
775         mutex_unlock(&usb_pcwd->mtx);
776
777         /* Delete the USB PCWD device */
778         usb_pcwd_delete(usb_pcwd);
779
780         cards_found--;
781
782         mutex_unlock(&disconnect_mutex);
783
784         printk(KERN_INFO PFX "USB PC Watchdog disconnected\n");
785 }
786
787
788
789 /**
790  *      usb_pcwd_init
791  */
792 static int __init usb_pcwd_init(void)
793 {
794         int result;
795
796         /* register this driver with the USB subsystem */
797         result = usb_register(&usb_pcwd_driver);
798         if (result) {
799                 printk(KERN_ERR PFX "usb_register failed. Error number %d\n",
800                     result);
801                 return result;
802         }
803
804         printk(KERN_INFO PFX DRIVER_DESC " v" DRIVER_VERSION " (" DRIVER_DATE ")\n");
805         return 0;
806 }
807
808
809 /**
810  *      usb_pcwd_exit
811  */
812 static void __exit usb_pcwd_exit(void)
813 {
814         /* deregister this driver with the USB subsystem */
815         usb_deregister(&usb_pcwd_driver);
816 }
817
818
819 module_init(usb_pcwd_init);
820 module_exit(usb_pcwd_exit);