switch lookup_mnt()
[linux-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 #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...) \
55         do { if (debug) printk(KERN_DEBUG PFX format "\n" , ## arg); } while (0)
56
57 /* Module and Version Information */
58 #define DRIVER_VERSION "1.02"
59 #define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
60 #define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
61 #define DRIVER_LICENSE "GPL"
62 #define DRIVER_NAME "pcwd_usb"
63 #define PFX DRIVER_NAME ": "
64
65 MODULE_AUTHOR(DRIVER_AUTHOR);
66 MODULE_DESCRIPTION(DRIVER_DESC);
67 MODULE_LICENSE(DRIVER_LICENSE);
68 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
69 MODULE_ALIAS_MISCDEV(TEMP_MINOR);
70
71 /* Module Parameters */
72 module_param(debug, int, 0);
73 MODULE_PARM_DESC(debug, "Debug enabled or not");
74
75 #define WATCHDOG_HEARTBEAT 0    /* default heartbeat =
76                                                 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. "
80         "(0<heartbeat<65536 or 0=delay-time from dip-switches, default="
81                                 __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
82
83 static int nowayout = WATCHDOG_NOWAYOUT;
84 module_param(nowayout, int, 0);
85 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
86                                 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
87
88 /* The vendor and product id's for the USB-PC Watchdog card */
89 #define USB_PCWD_VENDOR_ID      0x0c98
90 #define USB_PCWD_PRODUCT_ID     0x1140
91
92 /* table of devices that work with this driver */
93 static struct usb_device_id usb_pcwd_table[] = {
94         { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
95         { }                                     /* Terminating entry */
96 };
97 MODULE_DEVICE_TABLE(usb, usb_pcwd_table);
98
99 /* according to documentation max. time to process a command for the USB
100  * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */
101 #define USB_COMMAND_TIMEOUT     250
102
103 /* Watchdog's internal commands */
104 #define CMD_READ_TEMP                   0x02    /* Read Temperature;
105                                                         Re-trigger Watchdog */
106 #define CMD_TRIGGER                     CMD_READ_TEMP
107 #define CMD_GET_STATUS                  0x04    /* Get Status Information */
108 #define CMD_GET_FIRMWARE_VERSION        0x08    /* Get Firmware Version */
109 #define CMD_GET_DIP_SWITCH_SETTINGS     0x0c    /* Get Dip Switch Settings */
110 #define CMD_READ_WATCHDOG_TIMEOUT       0x18    /* Read Current Watchdog Time */
111 #define CMD_WRITE_WATCHDOG_TIMEOUT      0x19    /* Write Current WatchdogTime */
112 #define CMD_ENABLE_WATCHDOG             0x30    /* Enable / Disable Watchdog */
113 #define CMD_DISABLE_WATCHDOG            CMD_ENABLE_WATCHDOG
114
115 /* Watchdog's Dip Switch heartbeat values */
116 static const int heartbeat_tbl[] = {
117         5,      /* OFF-OFF-OFF  =  5 Sec  */
118         10,     /* OFF-OFF-ON   = 10 Sec  */
119         30,     /* OFF-ON-OFF   = 30 Sec  */
120         60,     /* OFF-ON-ON    =  1 Min  */
121         300,    /* ON-OFF-OFF   =  5 Min  */
122         600,    /* ON-OFF-ON    = 10 Min  */
123         1800,   /* ON-ON-OFF    = 30 Min  */
124         3600,   /* ON-ON-ON     =  1 hour */
125 };
126
127 /* We can only use 1 card due to the /dev/watchdog restriction */
128 static int cards_found;
129
130 /* some internal variables */
131 static unsigned long is_active;
132 static char expect_release;
133
134 /* Structure to hold all of our device specific stuff */
135 struct usb_pcwd_private {
136         /* save off the usb device pointer */
137         struct usb_device       *udev;
138         /* the interface for this device */
139         struct usb_interface    *interface;
140
141         /* the interface number used for cmd's */
142         unsigned int            interface_number;
143
144         /* the buffer to intr data */
145         unsigned char           *intr_buffer;
146         /* the dma address for the intr buffer */
147         dma_addr_t              intr_dma;
148         /* the size of the intr buffer */
149         size_t                  intr_size;
150         /* the urb used for the intr pipe */
151         struct urb              *intr_urb;
152
153         /* The command that is reported back */
154         unsigned char           cmd_command;
155         /* The data MSB that is reported back */
156         unsigned char           cmd_data_msb;
157         /* The data LSB that is reported back */
158         unsigned char           cmd_data_lsb;
159         /* true if we received a report after a command */
160         atomic_t                cmd_received;
161
162         /* Wether or not the device exists */
163         int                     exists;
164         /* locks this structure */
165         struct mutex            mtx;
166 };
167 static struct usb_pcwd_private *usb_pcwd_device;
168
169 /* prevent races between open() and disconnect() */
170 static DEFINE_MUTEX(disconnect_mutex);
171
172 /* local function prototypes */
173 static int usb_pcwd_probe(struct usb_interface *interface,
174                                                 const struct usb_device_id *id);
175 static void usb_pcwd_disconnect(struct usb_interface *interface);
176
177 /* usb specific object needed to register this driver with the usb subsystem */
178 static struct usb_driver usb_pcwd_driver = {
179         .name =         DRIVER_NAME,
180         .probe =        usb_pcwd_probe,
181         .disconnect =   usb_pcwd_disconnect,
182         .id_table =     usb_pcwd_table,
183 };
184
185
186 static void usb_pcwd_intr_done(struct urb *urb)
187 {
188         struct usb_pcwd_private *usb_pcwd =
189                                 (struct usb_pcwd_private *)urb->context;
190         unsigned char *data = usb_pcwd->intr_buffer;
191         int retval;
192
193         switch (urb->status) {
194         case 0:                 /* success */
195                 break;
196         case -ECONNRESET:       /* unlink */
197         case -ENOENT:
198         case -ESHUTDOWN:
199                 /* this urb is terminated, clean up */
200                 dbg("%s - urb shutting down with status: %d", __func__,
201                                                                 urb->status);
202                 return;
203         /* -EPIPE:  should clear the halt */
204         default:                /* error */
205                 dbg("%s - nonzero urb status received: %d", __func__,
206                                                                 urb->status);
207                 goto resubmit;
208         }
209
210         dbg("received following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
211                 data[0], data[1], data[2]);
212
213         usb_pcwd->cmd_command  = data[0];
214         usb_pcwd->cmd_data_msb = data[1];
215         usb_pcwd->cmd_data_lsb = data[2];
216
217         /* notify anyone waiting that the cmd has finished */
218         atomic_set(&usb_pcwd->cmd_received, 1);
219
220 resubmit:
221         retval = usb_submit_urb(urb, GFP_ATOMIC);
222         if (retval)
223                 printk(KERN_ERR PFX "can't resubmit intr, "
224                         "usb_submit_urb failed with result %d\n", retval);
225 }
226
227 static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd,
228                 unsigned char cmd, unsigned char *msb, unsigned char *lsb)
229 {
230         int got_response, count;
231         unsigned char buf[6];
232
233         /* We will not send any commands if the USB PCWD device does
234          * not exist */
235         if ((!usb_pcwd) || (!usb_pcwd->exists))
236                 return -1;
237
238         /* The USB PC Watchdog uses a 6 byte report format.
239          * The board currently uses only 3 of the six bytes of the report. */
240         buf[0] = cmd;                   /* Byte 0 = CMD */
241         buf[1] = *msb;                  /* Byte 1 = Data MSB */
242         buf[2] = *lsb;                  /* Byte 2 = Data LSB */
243         buf[3] = buf[4] = buf[5] = 0;   /* All other bytes not used */
244
245         dbg("sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
246                 buf[0], buf[1], buf[2]);
247
248         atomic_set(&usb_pcwd->cmd_received, 0);
249
250         if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
251                         HID_REQ_SET_REPORT, HID_DT_REPORT,
252                         0x0200, usb_pcwd->interface_number, buf, sizeof(buf),
253                         USB_COMMAND_TIMEOUT) != sizeof(buf)) {
254                 dbg("usb_pcwd_send_command: error in usb_control_msg for "
255                                 "cmd 0x%x 0x%x 0x%x\n", cmd, *msb, *lsb);
256         }
257         /* wait till the usb card processed the command,
258          * with a max. timeout of USB_COMMAND_TIMEOUT */
259         got_response = 0;
260         for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response);
261                                                                 count++) {
262                 mdelay(1);
263                 if (atomic_read(&usb_pcwd->cmd_received))
264                         got_response = 1;
265         }
266
267         if ((got_response) && (cmd == usb_pcwd->cmd_command)) {
268                 /* read back response */
269                 *msb = usb_pcwd->cmd_data_msb;
270                 *lsb = usb_pcwd->cmd_data_lsb;
271         }
272
273         return got_response;
274 }
275
276 static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd)
277 {
278         unsigned char msb = 0x00;
279         unsigned char lsb = 0x00;
280         int retval;
281
282         /* Enable Watchdog */
283         retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG,
284                                                                 &msb, &lsb);
285
286         if ((retval == 0) || (lsb == 0)) {
287                 printk(KERN_ERR PFX
288                                 "Card did not acknowledge enable attempt\n");
289                 return -1;
290         }
291
292         return 0;
293 }
294
295 static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd)
296 {
297         unsigned char msb = 0xA5;
298         unsigned char lsb = 0xC3;
299         int retval;
300
301         /* Disable Watchdog */
302         retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG,
303                                                                 &msb, &lsb);
304
305         if ((retval == 0) || (lsb != 0)) {
306                 printk(KERN_ERR PFX
307                         "Card did not acknowledge disable attempt\n");
308                 return -1;
309         }
310
311         return 0;
312 }
313
314 static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd)
315 {
316         unsigned char dummy;
317
318         /* Re-trigger Watchdog */
319         usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy);
320
321         return 0;
322 }
323
324 static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t)
325 {
326         unsigned char msb = t / 256;
327         unsigned char lsb = t % 256;
328
329         if ((t < 0x0001) || (t > 0xFFFF))
330                 return -EINVAL;
331
332         /* Write new heartbeat to watchdog */
333         usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb);
334
335         heartbeat = t;
336         return 0;
337 }
338
339 static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd,
340                                                         int *temperature)
341 {
342         unsigned char msb, lsb;
343
344         usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
345
346         /*
347          * Convert celsius to fahrenheit, since this was
348          * the decided 'standard' for this return value.
349          */
350         *temperature = (lsb * 9 / 5) + 32;
351
352         return 0;
353 }
354
355 static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd,
356                                                                 int *time_left)
357 {
358         unsigned char msb, lsb;
359
360         /* Read the time that's left before rebooting */
361         /* Note: if the board is not yet armed then we will read 0xFFFF */
362         usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
363
364         *time_left = (msb << 8) + lsb;
365
366         return 0;
367 }
368
369 /*
370  *      /dev/watchdog handling
371  */
372
373 static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
374                                                 size_t len, loff_t *ppos)
375 {
376         /* See if we got the magic character 'V' and reload the timer */
377         if (len) {
378                 if (!nowayout) {
379                         size_t i;
380
381                         /* note: just in case someone wrote the magic character
382                          * five months ago... */
383                         expect_release = 0;
384
385                         /* scan to see whether or not we got the
386                          * magic character */
387                         for (i = 0; i != len; i++) {
388                                 char c;
389                                 if (get_user(c, data + i))
390                                         return -EFAULT;
391                                 if (c == 'V')
392                                         expect_release = 42;
393                         }
394                 }
395
396                 /* someone wrote to us, we should reload the timer */
397                 usb_pcwd_keepalive(usb_pcwd_device);
398         }
399         return len;
400 }
401
402 static long usb_pcwd_ioctl(struct file *file, unsigned int cmd,
403                                                 unsigned long arg)
404 {
405         void __user *argp = (void __user *)arg;
406         int __user *p = argp;
407         static struct watchdog_info ident = {
408                 .options =              WDIOF_KEEPALIVEPING |
409                                         WDIOF_SETTIMEOUT |
410                                         WDIOF_MAGICCLOSE,
411                 .firmware_version =     1,
412                 .identity =             DRIVER_NAME,
413         };
414
415         switch (cmd) {
416         case WDIOC_GETSUPPORT:
417                 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
418
419         case WDIOC_GETSTATUS:
420         case WDIOC_GETBOOTSTATUS:
421                 return put_user(0, p);
422
423         case WDIOC_GETTEMP:
424         {
425                 int temperature;
426
427                 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
428                         return -EFAULT;
429
430                 return put_user(temperature, p);
431         }
432
433         case WDIOC_SETOPTIONS:
434         {
435                 int new_options, retval = -EINVAL;
436
437                 if (get_user(new_options, p))
438                         return -EFAULT;
439
440                 if (new_options & WDIOS_DISABLECARD) {
441                         usb_pcwd_stop(usb_pcwd_device);
442                         retval = 0;
443                 }
444
445                 if (new_options & WDIOS_ENABLECARD) {
446                         usb_pcwd_start(usb_pcwd_device);
447                         retval = 0;
448                 }
449
450                 return retval;
451         }
452
453         case WDIOC_KEEPALIVE:
454                 usb_pcwd_keepalive(usb_pcwd_device);
455                 return 0;
456
457         case WDIOC_SETTIMEOUT:
458         {
459                 int new_heartbeat;
460
461                 if (get_user(new_heartbeat, p))
462                         return -EFAULT;
463
464                 if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
465                         return -EINVAL;
466
467                 usb_pcwd_keepalive(usb_pcwd_device);
468                 /* Fall */
469         }
470
471         case WDIOC_GETTIMEOUT:
472                 return put_user(heartbeat, p);
473
474         case WDIOC_GETTIMELEFT:
475         {
476                 int time_left;
477
478                 if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left))
479                         return -EFAULT;
480
481                 return put_user(time_left, p);
482         }
483
484         default:
485                 return -ENOTTY;
486         }
487 }
488
489 static int usb_pcwd_open(struct inode *inode, struct file *file)
490 {
491         /* /dev/watchdog can only be opened once */
492         if (test_and_set_bit(0, &is_active))
493                 return -EBUSY;
494
495         /* Activate */
496         usb_pcwd_start(usb_pcwd_device);
497         usb_pcwd_keepalive(usb_pcwd_device);
498         return nonseekable_open(inode, file);
499 }
500
501 static int usb_pcwd_release(struct inode *inode, struct file *file)
502 {
503         /*
504          *      Shut off the timer.
505          */
506         if (expect_release == 42) {
507                 usb_pcwd_stop(usb_pcwd_device);
508         } else {
509                 printk(KERN_CRIT PFX
510                         "Unexpected close, not stopping watchdog!\n");
511                 usb_pcwd_keepalive(usb_pcwd_device);
512         }
513         expect_release = 0;
514         clear_bit(0, &is_active);
515         return 0;
516 }
517
518 /*
519  *      /dev/temperature handling
520  */
521
522 static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
523                                 size_t len, loff_t *ppos)
524 {
525         int temperature;
526
527         if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
528                 return -EFAULT;
529
530         if (copy_to_user(data, &temperature, 1))
531                 return -EFAULT;
532
533         return 1;
534 }
535
536 static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
537 {
538         return nonseekable_open(inode, file);
539 }
540
541 static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
542 {
543         return 0;
544 }
545
546 /*
547  *      Notify system
548  */
549
550 static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code,
551                                                                 void *unused)
552 {
553         if (code == SYS_DOWN || code == SYS_HALT)
554                 usb_pcwd_stop(usb_pcwd_device); /* Turn the WDT off */
555
556         return NOTIFY_DONE;
557 }
558
559 /*
560  *      Kernel Interfaces
561  */
562
563 static const struct file_operations usb_pcwd_fops = {
564         .owner =        THIS_MODULE,
565         .llseek =       no_llseek,
566         .write =        usb_pcwd_write,
567         .unlocked_ioctl = usb_pcwd_ioctl,
568         .open =         usb_pcwd_open,
569         .release =      usb_pcwd_release,
570 };
571
572 static struct miscdevice usb_pcwd_miscdev = {
573         .minor =        WATCHDOG_MINOR,
574         .name =         "watchdog",
575         .fops =         &usb_pcwd_fops,
576 };
577
578 static const struct file_operations usb_pcwd_temperature_fops = {
579         .owner =        THIS_MODULE,
580         .llseek =       no_llseek,
581         .read =         usb_pcwd_temperature_read,
582         .open =         usb_pcwd_temperature_open,
583         .release =      usb_pcwd_temperature_release,
584 };
585
586 static struct miscdevice usb_pcwd_temperature_miscdev = {
587         .minor =        TEMP_MINOR,
588         .name =         "temperature",
589         .fops =         &usb_pcwd_temperature_fops,
590 };
591
592 static struct notifier_block usb_pcwd_notifier = {
593         .notifier_call =        usb_pcwd_notify_sys,
594 };
595
596 /**
597  *      usb_pcwd_delete
598  */
599 static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd)
600 {
601         usb_free_urb(usb_pcwd->intr_urb);
602         if (usb_pcwd->intr_buffer != NULL)
603                 usb_buffer_free(usb_pcwd->udev, usb_pcwd->intr_size,
604                                 usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
605         kfree(usb_pcwd);
606 }
607
608 /**
609  *      usb_pcwd_probe
610  *
611  *      Called by the usb core when a new device is connected that it thinks
612  *      this driver might be interested in.
613  */
614 static int usb_pcwd_probe(struct usb_interface *interface,
615                                                 const struct usb_device_id *id)
616 {
617         struct usb_device *udev = interface_to_usbdev(interface);
618         struct usb_host_interface *iface_desc;
619         struct usb_endpoint_descriptor *endpoint;
620         struct usb_pcwd_private *usb_pcwd = NULL;
621         int pipe, maxp;
622         int retval = -ENOMEM;
623         int got_fw_rev;
624         unsigned char fw_rev_major, fw_rev_minor;
625         char fw_ver_str[20];
626         unsigned char option_switches, dummy;
627
628         cards_found++;
629         if (cards_found > 1) {
630                 printk(KERN_ERR PFX "This driver only supports 1 device\n");
631                 return -ENODEV;
632         }
633
634         /* get the active interface descriptor */
635         iface_desc = interface->cur_altsetting;
636
637         /* check out that we have a HID device */
638         if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
639                 printk(KERN_ERR PFX
640                         "The device isn't a Human Interface Device\n");
641                 return -ENODEV;
642         }
643
644         /* check out the endpoint: it has to be Interrupt & IN */
645         endpoint = &iface_desc->endpoint[0].desc;
646
647         if (!usb_endpoint_is_int_in(endpoint)) {
648                 /* we didn't find a Interrupt endpoint with direction IN */
649                 printk(KERN_ERR PFX "Couldn't find an INTR & IN endpoint\n");
650                 return -ENODEV;
651         }
652
653         /* get a handle to the interrupt data pipe */
654         pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
655         maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
656
657         /* allocate memory for our device and initialize it */
658         usb_pcwd = kzalloc(sizeof(struct usb_pcwd_private), GFP_KERNEL);
659         if (usb_pcwd == NULL) {
660                 printk(KERN_ERR PFX "Out of memory\n");
661                 goto error;
662         }
663
664         usb_pcwd_device = usb_pcwd;
665
666         mutex_init(&usb_pcwd->mtx);
667         usb_pcwd->udev = udev;
668         usb_pcwd->interface = interface;
669         usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
670         usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ?
671                                 le16_to_cpu(endpoint->wMaxPacketSize) : 8);
672
673         /* set up the memory buffer's */
674         usb_pcwd->intr_buffer = usb_buffer_alloc(udev, usb_pcwd->intr_size,
675                                         GFP_ATOMIC, &usb_pcwd->intr_dma);
676         if (!usb_pcwd->intr_buffer) {
677                 printk(KERN_ERR PFX "Out of memory\n");
678                 goto error;
679         }
680
681         /* allocate the urb's */
682         usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
683         if (!usb_pcwd->intr_urb) {
684                 printk(KERN_ERR PFX "Out of memory\n");
685                 goto error;
686         }
687
688         /* initialise the intr urb's */
689         usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
690                         usb_pcwd->intr_buffer, usb_pcwd->intr_size,
691                         usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
692         usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
693         usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
694
695         /* register our interrupt URB with the USB system */
696         if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
697                 printk(KERN_ERR PFX "Problem registering interrupt URB\n");
698                 retval = -EIO; /* failure */
699                 goto error;
700         }
701
702         /* The device exists and can be communicated with */
703         usb_pcwd->exists = 1;
704
705         /* disable card */
706         usb_pcwd_stop(usb_pcwd);
707
708         /* Get the Firmware Version */
709         got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION,
710                                                 &fw_rev_major, &fw_rev_minor);
711         if (got_fw_rev)
712                 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
713         else
714                 sprintf(fw_ver_str, "<card no answer>");
715
716         printk(KERN_INFO PFX "Found card (Firmware: %s) with temp option\n",
717                 fw_ver_str);
718
719         /* Get switch settings */
720         usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy,
721                                                         &option_switches);
722
723         printk(KERN_INFO PFX "Option switches (0x%02x): "
724                 "Temperature Reset Enable=%s, Power On Delay=%s\n",
725                 option_switches,
726                 ((option_switches & 0x10) ? "ON" : "OFF"),
727                 ((option_switches & 0x08) ? "ON" : "OFF"));
728
729         /* If heartbeat = 0 then we use the heartbeat from the dip-switches */
730         if (heartbeat == 0)
731                 heartbeat = heartbeat_tbl[(option_switches & 0x07)];
732
733         /* Check that the heartbeat value is within it's range ;
734          * if not reset to the default */
735         if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
736                 usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
737                 printk(KERN_INFO PFX
738                         "heartbeat value must be 0<heartbeat<65536, using %d\n",
739                         WATCHDOG_HEARTBEAT);
740         }
741
742         retval = register_reboot_notifier(&usb_pcwd_notifier);
743         if (retval != 0) {
744                 printk(KERN_ERR PFX
745                         "cannot register reboot notifier (err=%d)\n",
746                         retval);
747                 goto error;
748         }
749
750         retval = misc_register(&usb_pcwd_temperature_miscdev);
751         if (retval != 0) {
752                 printk(KERN_ERR PFX
753                         "cannot register miscdev on minor=%d (err=%d)\n",
754                         TEMP_MINOR, retval);
755                 goto err_out_unregister_reboot;
756         }
757
758         retval = misc_register(&usb_pcwd_miscdev);
759         if (retval != 0) {
760                 printk(KERN_ERR PFX
761                         "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         printk(KERN_INFO PFX "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         printk(KERN_INFO PFX "USB PC Watchdog disconnected\n");
828 }
829
830
831
832 /**
833  *      usb_pcwd_init
834  */
835 static int __init usb_pcwd_init(void)
836 {
837         int result;
838
839         /* register this driver with the USB subsystem */
840         result = usb_register(&usb_pcwd_driver);
841         if (result) {
842                 printk(KERN_ERR PFX "usb_register failed. Error number %d\n",
843                     result);
844                 return result;
845         }
846
847         printk(KERN_INFO PFX DRIVER_DESC " v" DRIVER_VERSION "\n");
848         return 0;
849 }
850
851
852 /**
853  *      usb_pcwd_exit
854  */
855 static void __exit usb_pcwd_exit(void)
856 {
857         /* deregister this driver with the USB subsystem */
858         usb_deregister(&usb_pcwd_driver);
859 }
860
861
862 module_init(usb_pcwd_init);
863 module_exit(usb_pcwd_exit);