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1 /* 1
2 * Berkshire USB-PC Watchdog Card Driver
3 *
4 * (c) Copyright 2004 Wim Van Sebroeck <w
5 *
6 * Based on source code of the following
7 * Ken Hollis <kenji@bitgate.com>,
8 * Alan Cox <alan@redhat.com>,
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
14 * modify it under the terms of the GNU G
15 * as published by the Free Software Foun
16 * 2 of the License, or (at your option)
17 *
18 * Neither Wim Van Sebroeck nor Iguana vz
19 * provide warranty for any of this softw
20 * provided "AS-IS" and at no charge.
21 *
22 * Thanks also to Simon Machell at Berksh
23 * providing the test hardware. More info
24 * http://www.berkprod.com/ or http://www
25 */
26
27 #include <linux/config.h>
28 #include <linux/kernel.h>
29 #include <linux/errno.h>
30 #include <linux/init.h>
31 #include <linux/slab.h>
32 #include <linux/module.h>
33 #include <linux/moduleparam.h>
34 #include <linux/types.h>
35 #include <linux/delay.h>
36 #include <linux/miscdevice.h>
37 #include <linux/watchdog.h>
38 #include <linux/notifier.h>
39 #include <linux/reboot.h>
40 #include <linux/fs.h>
41 #include <linux/smp_lock.h>
42 #include <linux/completion.h>
43 #include <asm/uaccess.h>
44 #include <linux/usb.h>
45
46
47 #ifdef CONFIG_USB_DEBUG
48 static int debug = 1;
49 #else
50 static int debug;
51 #endif
52
53 /* Use our own dbg macro */
54 #undef dbg
55 #define dbg(format, arg...) do { if (debug) pr
56
57
58 /* Module and Version Information */
59 #define DRIVER_VERSION "1.00"
60 #define DRIVER_DATE "12 Jun 2004"
61 #define DRIVER_AUTHOR "Wim Van Sebroeck <wim@i
62 #define DRIVER_DESC "Berkshire USB-PC Watchdog
63 #define DRIVER_LICENSE "GPL"
64 #define DRIVER_NAME "pcwd_usb"
65 #define PFX DRIVER_NAME ": "
66
67 MODULE_AUTHOR(DRIVER_AUTHOR);
68 MODULE_DESCRIPTION(DRIVER_DESC);
69 MODULE_LICENSE(DRIVER_LICENSE);
70 MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
71 MODULE_ALIAS_MISCDEV(TEMP_MINOR);
72
73 /* Module Parameters */
74 module_param(debug, int, 0);
75 MODULE_PARM_DESC(debug, "Debug enabled or not"
76
77 #define WATCHDOG_HEARTBEAT 2 /* 2 sec defau
78 static int heartbeat = WATCHDOG_HEARTBEAT;
79 module_param(heartbeat, int, 0);
80 MODULE_PARM_DESC(heartbeat, "Watchdog heartbea
81
82 #ifdef CONFIG_WATCHDOG_NOWAYOUT
83 static int nowayout = 1;
84 #else
85 static int nowayout = 0;
86 #endif
87
88 module_param(nowayout, int, 0);
89 MODULE_PARM_DESC(nowayout, "Watchdog cannot be
90
91 /* The vendor and product id's for the USB-PC
92 #define USB_PCWD_VENDOR_ID 0x0c98
93 #define USB_PCWD_PRODUCT_ID 0x1140
94
95 /* table of devices that work with this driver
96 static struct usb_device_id usb_pcwd_table []
97 { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_P
98 { }
99 };
100 MODULE_DEVICE_TABLE (usb, usb_pcwd_table);
101
102 /* according to documentation max. time to pro
103 * watchdog card is 100 or 200 ms, so we give
104 #define USB_COMMAND_TIMEOUT 250
105
106 /* Watchdog's internal commands */
107 #define CMD_READ_TEMP 0x02
108 #define CMD_TRIGGER CMD_RE
109 #define CMD_GET_STATUS 0x04
110 #define CMD_GET_FIRMWARE_VERSION 0x08
111 #define CMD_GET_DIP_SWITCH_SETTINGS 0x0c
112 #define CMD_READ_WATCHDOG_TIMEOUT 0x18
113 #define CMD_WRITE_WATCHDOG_TIMEOUT 0x19
114 #define CMD_ENABLE_WATCHDOG 0x30
115 #define CMD_DISABLE_WATCHDOG CMD_EN
116
117 /* Some defines that I like to be somewhere el
118 #define HID_REQ_SET_REPORT 0x09
119 #define HID_DT_REPORT (USB_T
120
121 /* We can only use 1 card due to the /dev/watc
122 static int cards_found;
123
124 /* some internal variables */
125 static unsigned long is_active;
126 static char expect_release;
127
128 /* Structure to hold all of our device specifi
129 struct usb_pcwd_private {
130 struct usb_device * udev;
131 struct usb_interface * interface;
132
133 unsigned int interface_numb
134
135 unsigned char * intr_buffer;
136 dma_addr_t intr_dma;
137 size_t intr_size;
138 struct urb * intr_urb;
139
140 unsigned char cmd_command;
141 unsigned char cmd_data_msb;
142 unsigned char cmd_data_lsb;
143 atomic_t cmd_received;
144
145 int exists;
146 struct semaphore sem;
147 };
148 static struct usb_pcwd_private *usb_pcwd_devic
149
150 /* prevent races between open() and disconnect
151 static DECLARE_MUTEX (disconnect_sem);
152
153 /* local function prototypes */
154 static int usb_pcwd_probe (struct usb_in
155 static void usb_pcwd_disconnect (struct usb_in
156
157 /* usb specific object needed to register this
158 static struct usb_driver usb_pcwd_driver = {
159 .owner = THIS_MODULE,
160 .name = DRIVER_NAME,
161 .probe = usb_pcwd_probe,
162 .disconnect = usb_pcwd_disconnect,
163 .id_table = usb_pcwd_table,
164 };
165
166
167 static void usb_pcwd_intr_done(struct urb *urb
168 {
169 struct usb_pcwd_private *usb_pcwd = (s
170 unsigned char *data = usb_pcwd->intr_b
171 int retval;
172
173 switch (urb->status) {
174 case 0: /* success */
175 break;
176 case -ECONNRESET: /* unlink */
177 case -ENOENT:
178 case -ESHUTDOWN:
179 /* this urb is terminated, cle
180 dbg("%s - urb shutting down wi
181 return;
182 /* -EPIPE: should clear the halt */
183 default: /* error */
184 dbg("%s - nonzero urb status r
185 goto resubmit;
186 }
187
188 dbg("received following data cmd=0x%02
189 data[0], data[1], data[2]);
190
191 usb_pcwd->cmd_command = data[0];
192 usb_pcwd->cmd_data_msb = data[1];
193 usb_pcwd->cmd_data_lsb = data[2];
194
195 /* notify anyone waiting that the cmd
196 atomic_set (&usb_pcwd->cmd_received, 1
197
198 resubmit:
199 retval = usb_submit_urb (urb, GFP_ATOM
200 if (retval)
201 printk(KERN_ERR PFX "can't res
202 retval);
203 }
204
205 static int usb_pcwd_send_command(struct usb_pc
206 unsigned char *msb, unsigned char *lsb
207 {
208 int got_response, count;
209 unsigned char buf[6];
210
211 /* We will not send any commands if th
212 if ((!usb_pcwd) || (!usb_pcwd->exists)
213 return -1;
214
215 /* The USB PC Watchdog uses a 6 byte r
216 * only 3 of the six bytes of the repo
217 buf[0] = cmd; /* Byt
218 buf[1] = *msb; /* Byt
219 buf[2] = *lsb; /* Byt
220 buf[3] = buf[4] = buf[5] = 0; /* All
221
222 dbg("sending following data cmd=0x%02x
223 buf[0], buf[1], buf[2]);
224
225 atomic_set (&usb_pcwd->cmd_received, 0
226
227 if (usb_control_msg(usb_pcwd->udev, us
228 HID_REQ_SET_REPORT, HI
229 0x0200, usb_pcwd->inte
230 HZ) != sizeof(buf)) {
231 dbg("usb_pcwd_send_command: er
232 }
233 /* wait till the usb card processed th
234 * with a max. timeout of USB_COMMAND_
235 got_response = 0;
236 for (count = 0; (count < USB_COMMAND_T
237 mdelay(1);
238 if (atomic_read (&usb_pcwd->cm
239 got_response = 1;
240 }
241
242 if ((got_response) && (cmd == usb_pcwd
243 /* read back response */
244 *msb = usb_pcwd->cmd_data_msb;
245 *lsb = usb_pcwd->cmd_data_lsb;
246 }
247
248 return got_response;
249 }
250
251 static int usb_pcwd_start(struct usb_pcwd_priv
252 {
253 unsigned char msb = 0x00;
254 unsigned char lsb = 0x00;
255 int retval;
256
257 /* Enable Watchdog */
258 retval = usb_pcwd_send_command(usb_pcw
259
260 if ((retval == 0) || (lsb == 0)) {
261 printk(KERN_ERR PFX "Card did
262 return -1;
263 }
264
265 return 0;
266 }
267
268 static int usb_pcwd_stop(struct usb_pcwd_priva
269 {
270 unsigned char msb = 0xA5;
271 unsigned char lsb = 0xC3;
272 int retval;
273
274 /* Disable Watchdog */
275 retval = usb_pcwd_send_command(usb_pcw
276
277 if ((retval == 0) || (lsb != 0)) {
278 printk(KERN_ERR PFX "Card did
279 return -1;
280 }
281
282 return 0;
283 }
284
285 static int usb_pcwd_keepalive(struct usb_pcwd_
286 {
287 unsigned char dummy;
288
289 /* Re-trigger Watchdog */
290 usb_pcwd_send_command(usb_pcwd, CMD_TR
291
292 return 0;
293 }
294
295 static int usb_pcwd_set_heartbeat(struct usb_p
296 {
297 unsigned char msb = t / 256;
298 unsigned char lsb = t % 256;
299
300 if ((t < 0x0001) || (t > 0xFFFF))
301 return -EINVAL;
302
303 /* Write new heartbeat to watchdog */
304 usb_pcwd_send_command(usb_pcwd, CMD_WR
305
306 heartbeat = t;
307 return 0;
308 }
309
310 static int usb_pcwd_get_temperature(struct usb
311 {
312 unsigned char msb, lsb;
313
314 usb_pcwd_send_command(usb_pcwd, CMD_RE
315
316 /*
317 * Convert celsius to fahrenheit, sinc
318 * the decided 'standard' for this ret
319 */
320 *temperature = (lsb * 9 / 5) + 32;
321
322 return 0;
323 }
324
325 /*
326 * /dev/watchdog handling
327 */
328
329 static ssize_t usb_pcwd_write(struct file *fil
330 size_t len, loff
331 {
332 /* See if we got the magic character '
333 if (len) {
334 if (!nowayout) {
335 size_t i;
336
337 /* note: just in case
338 * five months ago...
339 expect_release = 0;
340
341 /* scan to see whether
342 for (i = 0; i != len;
343 char c;
344 if(get_user(c,
345 return
346 if (c == 'V')
347 expect
348 }
349 }
350
351 /* someone wrote to us, we sho
352 usb_pcwd_keepalive(usb_pcwd_de
353 }
354 return len;
355 }
356
357 static int usb_pcwd_ioctl(struct inode *inode,
358 unsigned int cmd, un
359 {
360 void __user *argp = (void __user *)arg
361 int __user *p = argp;
362 static struct watchdog_info ident = {
363 .options = WDIOF_
364 WDIOF_
365 WDIOF_
366 .firmware_version = 1,
367 .identity = DRIVER
368 };
369
370 switch (cmd) {
371 case WDIOC_GETSUPPORT:
372 return copy_to_user(ar
373 sizeof (ident)
374
375 case WDIOC_GETSTATUS:
376 case WDIOC_GETBOOTSTATUS:
377 return put_user(0, p);
378
379 case WDIOC_GETTEMP:
380 {
381 int temperature;
382
383 if (usb_pcwd_get_tempe
384 return -EFAULT
385
386 return put_user(temper
387 }
388
389 case WDIOC_KEEPALIVE:
390 usb_pcwd_keepalive(usb
391 return 0;
392
393 case WDIOC_SETOPTIONS:
394 {
395 int new_options, retva
396
397 if (get_user (new_opti
398 return -EFAULT
399
400 if (new_options & WDIO
401 usb_pcwd_stop(
402 retval = 0;
403 }
404
405 if (new_options & WDIO
406 usb_pcwd_start
407 retval = 0;
408 }
409
410 return retval;
411 }
412
413 case WDIOC_SETTIMEOUT:
414 {
415 int new_heartbeat;
416
417 if (get_user(new_heart
418 return -EFAULT
419
420 if (usb_pcwd_set_heart
421 return -EINVAL;
422
423 usb_pcwd_keepalive(usb
424 /* Fall */
425 }
426
427 case WDIOC_GETTIMEOUT:
428 return put_user(heartb
429
430 default:
431 return -ENOIOCTLCMD;
432 }
433 }
434
435 static int usb_pcwd_open(struct inode *inode,
436 {
437 /* /dev/watchdog can only be opened on
438 if (test_and_set_bit(0, &is_active))
439 return -EBUSY;
440
441 /* Activate */
442 usb_pcwd_start(usb_pcwd_device);
443 usb_pcwd_keepalive(usb_pcwd_device);
444 return nonseekable_open(inode, file);
445 }
446
447 static int usb_pcwd_release(struct inode *inod
448 {
449 /*
450 * Shut off the timer.
451 */
452 if (expect_release == 42) {
453 usb_pcwd_stop(usb_pcwd_device)
454 } else {
455 printk(KERN_CRIT PFX "Unexpect
456 usb_pcwd_keepalive(usb_pcwd_de
457 }
458 expect_release = 0;
459 clear_bit(0, &is_active);
460 return 0;
461 }
462
463 /*
464 * /dev/temperature handling
465 */
466
467 static ssize_t usb_pcwd_temperature_read(struc
468 size_t len, lo
469 {
470 int temperature;
471
472 if (usb_pcwd_get_temperature(usb_pcwd_
473 return -EFAULT;
474
475 if (copy_to_user(data, &temperature, 1
476 return -EFAULT;
477
478 return 1;
479 }
480
481 static int usb_pcwd_temperature_open(struct in
482 {
483 return nonseekable_open(inode, file);
484 }
485
486 static int usb_pcwd_temperature_release(struct
487 {
488 return 0;
489 }
490
491 /*
492 * Notify system
493 */
494
495 static int usb_pcwd_notify_sys(struct notifier
496 {
497 if (code==SYS_DOWN || code==SYS_HALT)
498 /* Turn the WDT off */
499 usb_pcwd_stop(usb_pcwd_device)
500 }
501
502 return NOTIFY_DONE;
503 }
504
505 /*
506 * Kernel Interfaces
507 */
508
509 static struct file_operations usb_pcwd_fops =
510 .owner = THIS_MODULE,
511 .llseek = no_llseek,
512 .write = usb_pcwd_write,
513 .ioctl = usb_pcwd_ioctl,
514 .open = usb_pcwd_open,
515 .release = usb_pcwd_release,
516 };
517
518 static struct miscdevice usb_pcwd_miscdev = {
519 .minor = WATCHDOG_MINOR,
520 .name = "watchdog",
521 .fops = &usb_pcwd_fops,
522 };
523
524 static struct file_operations usb_pcwd_tempera
525 .owner = THIS_MODULE,
526 .llseek = no_llseek,
527 .read = usb_pcwd_temperature_r
528 .open = usb_pcwd_temperature_o
529 .release = usb_pcwd_temperature_r
530 };
531
532 static struct miscdevice usb_pcwd_temperature_
533 .minor = TEMP_MINOR,
534 .name = "temperature",
535 .fops = &usb_pcwd_temperature_
536 };
537
538 static struct notifier_block usb_pcwd_notifier
539 .notifier_call = usb_pcwd_notif
540 };
541
542 /**
543 * usb_pcwd_delete
544 */
545 static inline void usb_pcwd_delete (struct usb
546 {
547 if (usb_pcwd->intr_urb != NULL)
548 usb_free_urb (usb_pcwd->intr_u
549 if (usb_pcwd->intr_buffer != NULL)
550 usb_buffer_free(usb_pcwd->udev
551 usb_pcwd->intr
552 kfree (usb_pcwd);
553 }
554
555 /**
556 * usb_pcwd_probe
557 *
558 * Called by the usb core when a new devi
559 * this driver might be interested in.
560 */
561 static int usb_pcwd_probe(struct usb_interface
562 {
563 struct usb_device *udev = interface_to
564 struct usb_host_interface *iface_desc;
565 struct usb_endpoint_descriptor *endpoi
566 struct usb_pcwd_private *usb_pcwd = NU
567 int pipe, maxp;
568 int retval = -ENOMEM;
569 int got_fw_rev;
570 unsigned char fw_rev_major, fw_rev_min
571 char fw_ver_str[20];
572 unsigned char option_switches, dummy;
573
574 cards_found++;
575 if (cards_found > 1) {
576 printk(KERN_ERR PFX "This driv
577 return -ENODEV;
578 }
579
580 /* get the active interface descriptor
581 iface_desc = interface->cur_altsetting
582
583 /* check out that we have a HID device
584 if (!(iface_desc->desc.bInterfaceClass
585 printk(KERN_ERR PFX "The devic
586 return -ENODEV;
587 }
588
589 /* check out the endpoint: it has to b
590 endpoint = &iface_desc->endpoint[0].de
591
592 if (!((endpoint->bEndpointAddress & US
593 ((endpoint->bmAttributes & USB_EN
594 == USB_ENDPOIN
595 /* we didn't find a Interrupt
596 printk(KERN_ERR PFX "Couldn't
597 return -ENODEV;
598 }
599
600 /* get a handle to the interrupt data
601 pipe = usb_rcvintpipe(udev, endpoint->
602 maxp = usb_maxpacket(udev, pipe, usb_p
603
604 /* allocate memory for our device and
605 usb_pcwd = kmalloc (sizeof(struct usb_
606 if (usb_pcwd == NULL) {
607 printk(KERN_ERR PFX "Out of me
608 goto error;
609 }
610 memset (usb_pcwd, 0x00, sizeof (*usb_p
611
612 usb_pcwd_device = usb_pcwd;
613
614 init_MUTEX (&usb_pcwd->sem);
615 usb_pcwd->udev = udev;
616 usb_pcwd->interface = interface;
617 usb_pcwd->interface_number = iface_des
618 usb_pcwd->intr_size = (le16_to_cpu(end
619
620 /* set up the memory buffer's */
621 if (!(usb_pcwd->intr_buffer = usb_buff
622 printk(KERN_ERR PFX "Out of me
623 goto error;
624 }
625
626 /* allocate the urb's */
627 usb_pcwd->intr_urb = usb_alloc_urb(0,
628 if (!usb_pcwd->intr_urb) {
629 printk(KERN_ERR PFX "Out of me
630 goto error;
631 }
632
633 /* initialise the intr urb's */
634 usb_fill_int_urb(usb_pcwd->intr_urb, u
635 usb_pcwd->intr_buffer,
636 usb_pcwd_intr_done, us
637 usb_pcwd->intr_urb->transfer_dma = usb
638 usb_pcwd->intr_urb->transfer_flags |=
639
640 /* register our interrupt URB with the
641 if (usb_submit_urb(usb_pcwd->intr_urb,
642 printk(KERN_ERR PFX "Problem r
643 retval = -EIO; /* failure */
644 goto error;
645 }
646
647 /* The device exists and can be commun
648 usb_pcwd->exists = 1;
649
650 /* disable card */
651 usb_pcwd_stop(usb_pcwd);
652
653 /* Get the Firmware Version */
654 got_fw_rev = usb_pcwd_send_command(usb
655 if (got_fw_rev) {
656 sprintf(fw_ver_str, "%u.%02u",
657 } else {
658 sprintf(fw_ver_str, "<card no
659 }
660
661 printk(KERN_INFO PFX "Found card (Firm
662 fw_ver_str);
663
664 /* Get switch settings */
665 usb_pcwd_send_command(usb_pcwd, CMD_GE
666
667 printk(KERN_INFO PFX "Option switches
668 option_switches,
669 ((option_switches & 0x10) ? "O
670 ((option_switches & 0x08) ? "O
671
672 /* Check that the heartbeat value is w
673 if (usb_pcwd_set_heartbeat(usb_pcwd, h
674 usb_pcwd_set_heartbeat(usb_pcw
675 printk(KERN_INFO PFX "heartbea
676 WATCHDOG_HEARTBEAT);
677 }
678
679 retval = register_reboot_notifier(&usb
680 if (retval != 0) {
681 printk(KERN_ERR PFX "cannot re
682 retval);
683 goto error;
684 }
685
686 retval = misc_register(&usb_pcwd_tempe
687 if (retval != 0) {
688 printk(KERN_ERR PFX "cannot re
689 TEMP_MINOR, retval);
690 goto err_out_unregister_reboot
691 }
692
693 retval = misc_register(&usb_pcwd_miscd
694 if (retval != 0) {
695 printk(KERN_ERR PFX "cannot re
696 WATCHDOG_MINOR, retval
697 goto err_out_misc_deregister;
698 }
699
700 /* we can register the device now, as
701 usb_set_intfdata (interface, usb_pcwd)
702
703 printk(KERN_INFO PFX "initialized. hea
704 heartbeat, nowayout);
705
706 return 0;
707
708 err_out_misc_deregister:
709 misc_deregister(&usb_pcwd_temperature_
710 err_out_unregister_reboot:
711 unregister_reboot_notifier(&usb_pcwd_n
712 error:
713 usb_pcwd_delete (usb_pcwd);
714 usb_pcwd_device = NULL;
715 return retval;
716 }
717
718
719 /**
720 * usb_pcwd_disconnect
721 *
722 * Called by the usb core when the device
723 *
724 * This routine guarantees that the drive
725 * by clearing dev->udev.
726 */
727 static void usb_pcwd_disconnect(struct usb_int
728 {
729 struct usb_pcwd_private *usb_pcwd;
730
731 /* prevent races with open() */
732 down (&disconnect_sem);
733
734 usb_pcwd = usb_get_intfdata (interface
735 usb_set_intfdata (interface, NULL);
736
737 down (&usb_pcwd->sem);
738
739 /* Stop the timer before we leave */
740 if (!nowayout)
741 usb_pcwd_stop(usb_pcwd);
742
743 /* We should now stop communicating wi
744 usb_pcwd->exists = 0;
745
746 /* Deregister */
747 misc_deregister(&usb_pcwd_miscdev);
748 misc_deregister(&usb_pcwd_temperature_
749 unregister_reboot_notifier(&usb_pcwd_n
750
751 up (&usb_pcwd->sem);
752
753 /* Delete the USB PCWD device */
754 usb_pcwd_delete(usb_pcwd);
755
756 cards_found--;
757
758 up (&disconnect_sem);
759
760 printk(KERN_INFO PFX "USB PC Watchdog
761 }
762
763
764
765 /**
766 * usb_pcwd_init
767 */
768 static int __init usb_pcwd_init(void)
769 {
770 int result;
771
772 /* register this driver with the USB s
773 result = usb_register(&usb_pcwd_driver
774 if (result) {
775 printk(KERN_ERR PFX "usb_regis
776 result);
777 return result;
778 }
779
780 printk(KERN_INFO PFX DRIVER_DESC " v"
781 return 0;
782 }
783
784
785 /**
786 * usb_pcwd_exit
787 */
788 static void __exit usb_pcwd_exit(void)
789 {
790 /* deregister this driver with the USB
791 usb_deregister(&usb_pcwd_driver);
792 }
793
794
795 module_init (usb_pcwd_init);
796 module_exit (usb_pcwd_exit);
797
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