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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
65MODULE_AUTHOR(DRIVER_AUTHOR);
66MODULE_DESCRIPTION(DRIVER_DESC);
67MODULE_LICENSE(DRIVER_LICENSE);
68MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
69MODULE_ALIAS_MISCDEV(TEMP_MINOR);
70
71/* Module Parameters */
72module_param(debug, int, 0);
73MODULE_PARM_DESC(debug, "Debug enabled or not");
74
75#define WATCHDOG_HEARTBEAT 0 /* default heartbeat =
76 delay-time from dip-switches */
77static int heartbeat = WATCHDOG_HEARTBEAT;
78module_param(heartbeat, int, 0);
79MODULE_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
83static int nowayout = WATCHDOG_NOWAYOUT;
84module_param(nowayout, int, 0);
85MODULE_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 */
93static struct usb_device_id usb_pcwd_table[] = {
94 { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
95 { } /* Terminating entry */
96};
97MODULE_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 */
116static 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 */
128static int cards_found;
129
130/* some internal variables */
131static unsigned long is_active;
132static char expect_release;
133
134/* Structure to hold all of our device specific stuff */
135struct 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};
167static struct usb_pcwd_private *usb_pcwd_device;
168
169/* prevent races between open() and disconnect() */
170static DEFINE_MUTEX(disconnect_mutex);
171
172/* local function prototypes */
173static int usb_pcwd_probe(struct usb_interface *interface,
174 const struct usb_device_id *id);
175static void usb_pcwd_disconnect(struct usb_interface *interface);
176
177/* usb specific object needed to register this driver with the usb subsystem */
178static 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
186static 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
220resubmit:
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
227static 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
276static 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
295static 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
314static 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
324static 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
339static 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
355static 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
373static 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
402static 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 const 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
489static 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
501static 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
522static 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
536static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
537{
538 return nonseekable_open(inode, file);
539}
540
541static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
542{
543 return 0;
544}
545
546/*
547 * Notify system
548 */
549
550static 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
563static 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
572static struct miscdevice usb_pcwd_miscdev = {
573 .minor = WATCHDOG_MINOR,
574 .name = "watchdog",
575 .fops = &usb_pcwd_fops,
576};
577
578static 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
586static struct miscdevice usb_pcwd_temperature_miscdev = {
587 .minor = TEMP_MINOR,
588 .name = "temperature",
589 .fops = &usb_pcwd_temperature_fops,
590};
591
592static struct notifier_block usb_pcwd_notifier = {
593 .notifier_call = usb_pcwd_notify_sys,
594};
595
596/**
597 * usb_pcwd_delete
598 */
599static 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_free_coherent(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 */
614static 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_alloc_coherent(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
774err_out_misc_deregister:
775 misc_deregister(&usb_pcwd_temperature_miscdev);
776err_out_unregister_reboot:
777 unregister_reboot_notifier(&usb_pcwd_notifier);
778error:
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 */
794static 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 */
835static 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 */
855static void __exit usb_pcwd_exit(void)
856{
857 /* deregister this driver with the USB subsystem */
858 usb_deregister(&usb_pcwd_driver);
859}
860
861
862module_init(usb_pcwd_init);
863module_exit(usb_pcwd_exit);
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Berkshire USB-PC Watchdog Card Driver
4 *
5 * (c) Copyright 2004-2007 Wim Van Sebroeck <wim@iguana.be>.
6 *
7 * Based on source code of the following authors:
8 * Ken Hollis <kenji@bitgate.com>,
9 * Alan Cox <alan@lxorguk.ukuu.org.uk>,
10 * Matt Domsch <Matt_Domsch@dell.com>,
11 * Rob Radez <rob@osinvestor.com>,
12 * Greg Kroah-Hartman <greg@kroah.com>
13 *
14 * Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
15 * provide warranty for any of this software. This material is
16 * provided "AS-IS" and at no charge.
17 *
18 * Thanks also to Simon Machell at Berkshire Products Inc. for
19 * providing the test hardware. More info is available at
20 * http://www.berkprod.com/ or http://www.pcwatchdog.com/
21 */
22
23#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
24
25#include <linux/module.h> /* For module specific items */
26#include <linux/moduleparam.h> /* For new moduleparam's */
27#include <linux/types.h> /* For standard types (like size_t) */
28#include <linux/errno.h> /* For the -ENODEV/... values */
29#include <linux/kernel.h> /* For printk/panic/... */
30#include <linux/delay.h> /* For mdelay function */
31#include <linux/miscdevice.h> /* For struct miscdevice */
32#include <linux/watchdog.h> /* For the watchdog specific items */
33#include <linux/notifier.h> /* For notifier support */
34#include <linux/reboot.h> /* For reboot_notifier stuff */
35#include <linux/init.h> /* For __init/__exit/... */
36#include <linux/fs.h> /* For file operations */
37#include <linux/usb.h> /* For USB functions */
38#include <linux/slab.h> /* For kmalloc, ... */
39#include <linux/mutex.h> /* For mutex locking */
40#include <linux/hid.h> /* For HID_REQ_SET_REPORT & HID_DT_REPORT */
41#include <linux/uaccess.h> /* For copy_to_user/put_user/... */
42
43
44/* Module and Version Information */
45#define DRIVER_VERSION "1.02"
46#define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
47#define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
48#define DRIVER_NAME "pcwd_usb"
49
50MODULE_AUTHOR(DRIVER_AUTHOR);
51MODULE_DESCRIPTION(DRIVER_DESC);
52MODULE_LICENSE("GPL");
53
54#define WATCHDOG_HEARTBEAT 0 /* default heartbeat =
55 delay-time from dip-switches */
56static int heartbeat = WATCHDOG_HEARTBEAT;
57module_param(heartbeat, int, 0);
58MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. "
59 "(0<heartbeat<65536 or 0=delay-time from dip-switches, default="
60 __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
61
62static bool nowayout = WATCHDOG_NOWAYOUT;
63module_param(nowayout, bool, 0);
64MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
65 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
66
67/* The vendor and product id's for the USB-PC Watchdog card */
68#define USB_PCWD_VENDOR_ID 0x0c98
69#define USB_PCWD_PRODUCT_ID 0x1140
70
71/* table of devices that work with this driver */
72static const struct usb_device_id usb_pcwd_table[] = {
73 { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
74 { } /* Terminating entry */
75};
76MODULE_DEVICE_TABLE(usb, usb_pcwd_table);
77
78/* according to documentation max. time to process a command for the USB
79 * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */
80#define USB_COMMAND_TIMEOUT 250
81
82/* Watchdog's internal commands */
83#define CMD_READ_TEMP 0x02 /* Read Temperature;
84 Re-trigger Watchdog */
85#define CMD_TRIGGER CMD_READ_TEMP
86#define CMD_GET_STATUS 0x04 /* Get Status Information */
87#define CMD_GET_FIRMWARE_VERSION 0x08 /* Get Firmware Version */
88#define CMD_GET_DIP_SWITCH_SETTINGS 0x0c /* Get Dip Switch Settings */
89#define CMD_READ_WATCHDOG_TIMEOUT 0x18 /* Read Current Watchdog Time */
90#define CMD_WRITE_WATCHDOG_TIMEOUT 0x19 /* Write Current WatchdogTime */
91#define CMD_ENABLE_WATCHDOG 0x30 /* Enable / Disable Watchdog */
92#define CMD_DISABLE_WATCHDOG CMD_ENABLE_WATCHDOG
93
94/* Watchdog's Dip Switch heartbeat values */
95static const int heartbeat_tbl[] = {
96 5, /* OFF-OFF-OFF = 5 Sec */
97 10, /* OFF-OFF-ON = 10 Sec */
98 30, /* OFF-ON-OFF = 30 Sec */
99 60, /* OFF-ON-ON = 1 Min */
100 300, /* ON-OFF-OFF = 5 Min */
101 600, /* ON-OFF-ON = 10 Min */
102 1800, /* ON-ON-OFF = 30 Min */
103 3600, /* ON-ON-ON = 1 hour */
104};
105
106/* We can only use 1 card due to the /dev/watchdog restriction */
107static int cards_found;
108
109/* some internal variables */
110static unsigned long is_active;
111static char expect_release;
112
113/* Structure to hold all of our device specific stuff */
114struct usb_pcwd_private {
115 /* save off the usb device pointer */
116 struct usb_device *udev;
117 /* the interface for this device */
118 struct usb_interface *interface;
119
120 /* the interface number used for cmd's */
121 unsigned int interface_number;
122
123 /* the buffer to intr data */
124 unsigned char *intr_buffer;
125 /* the dma address for the intr buffer */
126 dma_addr_t intr_dma;
127 /* the size of the intr buffer */
128 size_t intr_size;
129 /* the urb used for the intr pipe */
130 struct urb *intr_urb;
131
132 /* The command that is reported back */
133 unsigned char cmd_command;
134 /* The data MSB that is reported back */
135 unsigned char cmd_data_msb;
136 /* The data LSB that is reported back */
137 unsigned char cmd_data_lsb;
138 /* true if we received a report after a command */
139 atomic_t cmd_received;
140
141 /* Wether or not the device exists */
142 int exists;
143 /* locks this structure */
144 struct mutex mtx;
145};
146static struct usb_pcwd_private *usb_pcwd_device;
147
148/* prevent races between open() and disconnect() */
149static DEFINE_MUTEX(disconnect_mutex);
150
151/* local function prototypes */
152static int usb_pcwd_probe(struct usb_interface *interface,
153 const struct usb_device_id *id);
154static void usb_pcwd_disconnect(struct usb_interface *interface);
155
156/* usb specific object needed to register this driver with the usb subsystem */
157static struct usb_driver usb_pcwd_driver = {
158 .name = DRIVER_NAME,
159 .probe = usb_pcwd_probe,
160 .disconnect = usb_pcwd_disconnect,
161 .id_table = usb_pcwd_table,
162};
163
164
165static void usb_pcwd_intr_done(struct urb *urb)
166{
167 struct usb_pcwd_private *usb_pcwd =
168 (struct usb_pcwd_private *)urb->context;
169 unsigned char *data = usb_pcwd->intr_buffer;
170 struct device *dev = &usb_pcwd->interface->dev;
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, clean up */
180 dev_dbg(dev, "%s - urb shutting down with status: %d",
181 __func__, urb->status);
182 return;
183 /* -EPIPE: should clear the halt */
184 default: /* error */
185 dev_dbg(dev, "%s - nonzero urb status received: %d",
186 __func__, urb->status);
187 goto resubmit;
188 }
189
190 dev_dbg(dev, "received following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
191 data[0], data[1], data[2]);
192
193 usb_pcwd->cmd_command = data[0];
194 usb_pcwd->cmd_data_msb = data[1];
195 usb_pcwd->cmd_data_lsb = data[2];
196
197 /* notify anyone waiting that the cmd has finished */
198 atomic_set(&usb_pcwd->cmd_received, 1);
199
200resubmit:
201 retval = usb_submit_urb(urb, GFP_ATOMIC);
202 if (retval)
203 pr_err("can't resubmit intr, usb_submit_urb failed with result %d\n",
204 retval);
205}
206
207static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd,
208 unsigned char cmd, unsigned char *msb, unsigned char *lsb)
209{
210 int got_response, count;
211 unsigned char *buf;
212
213 /* We will not send any commands if the USB PCWD device does
214 * not exist */
215 if ((!usb_pcwd) || (!usb_pcwd->exists))
216 return -1;
217
218 buf = kmalloc(6, GFP_KERNEL);
219 if (buf == NULL)
220 return 0;
221
222 /* The USB PC Watchdog uses a 6 byte report format.
223 * The board currently uses only 3 of the six bytes of the report. */
224 buf[0] = cmd; /* Byte 0 = CMD */
225 buf[1] = *msb; /* Byte 1 = Data MSB */
226 buf[2] = *lsb; /* Byte 2 = Data LSB */
227 buf[3] = buf[4] = buf[5] = 0; /* All other bytes not used */
228
229 dev_dbg(&usb_pcwd->interface->dev,
230 "sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
231 buf[0], buf[1], buf[2]);
232
233 atomic_set(&usb_pcwd->cmd_received, 0);
234
235 if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
236 HID_REQ_SET_REPORT, HID_DT_REPORT,
237 0x0200, usb_pcwd->interface_number, buf, 6,
238 USB_COMMAND_TIMEOUT) != 6) {
239 dev_dbg(&usb_pcwd->interface->dev,
240 "usb_pcwd_send_command: error in usb_control_msg for cmd 0x%x 0x%x 0x%x\n",
241 cmd, *msb, *lsb);
242 }
243 /* wait till the usb card processed the command,
244 * with a max. timeout of USB_COMMAND_TIMEOUT */
245 got_response = 0;
246 for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response);
247 count++) {
248 mdelay(1);
249 if (atomic_read(&usb_pcwd->cmd_received))
250 got_response = 1;
251 }
252
253 if ((got_response) && (cmd == usb_pcwd->cmd_command)) {
254 /* read back response */
255 *msb = usb_pcwd->cmd_data_msb;
256 *lsb = usb_pcwd->cmd_data_lsb;
257 }
258
259 kfree(buf);
260
261 return got_response;
262}
263
264static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd)
265{
266 unsigned char msb = 0x00;
267 unsigned char lsb = 0x00;
268 int retval;
269
270 /* Enable Watchdog */
271 retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG,
272 &msb, &lsb);
273
274 if ((retval == 0) || (lsb == 0)) {
275 pr_err("Card did not acknowledge enable attempt\n");
276 return -1;
277 }
278
279 return 0;
280}
281
282static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd)
283{
284 unsigned char msb = 0xA5;
285 unsigned char lsb = 0xC3;
286 int retval;
287
288 /* Disable Watchdog */
289 retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG,
290 &msb, &lsb);
291
292 if ((retval == 0) || (lsb != 0)) {
293 pr_err("Card did not acknowledge disable attempt\n");
294 return -1;
295 }
296
297 return 0;
298}
299
300static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd)
301{
302 unsigned char dummy;
303
304 /* Re-trigger Watchdog */
305 usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy);
306
307 return 0;
308}
309
310static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t)
311{
312 unsigned char msb = t / 256;
313 unsigned char lsb = t % 256;
314
315 if ((t < 0x0001) || (t > 0xFFFF))
316 return -EINVAL;
317
318 /* Write new heartbeat to watchdog */
319 usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb);
320
321 heartbeat = t;
322 return 0;
323}
324
325static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd,
326 int *temperature)
327{
328 unsigned char msb, lsb;
329
330 usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
331
332 /*
333 * Convert celsius to fahrenheit, since this was
334 * the decided 'standard' for this return value.
335 */
336 *temperature = (lsb * 9 / 5) + 32;
337
338 return 0;
339}
340
341static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd,
342 int *time_left)
343{
344 unsigned char msb, lsb;
345
346 /* Read the time that's left before rebooting */
347 /* Note: if the board is not yet armed then we will read 0xFFFF */
348 usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
349
350 *time_left = (msb << 8) + lsb;
351
352 return 0;
353}
354
355/*
356 * /dev/watchdog handling
357 */
358
359static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
360 size_t len, loff_t *ppos)
361{
362 /* See if we got the magic character 'V' and reload the timer */
363 if (len) {
364 if (!nowayout) {
365 size_t i;
366
367 /* note: just in case someone wrote the magic character
368 * five months ago... */
369 expect_release = 0;
370
371 /* scan to see whether or not we got the
372 * magic character */
373 for (i = 0; i != len; i++) {
374 char c;
375 if (get_user(c, data + i))
376 return -EFAULT;
377 if (c == 'V')
378 expect_release = 42;
379 }
380 }
381
382 /* someone wrote to us, we should reload the timer */
383 usb_pcwd_keepalive(usb_pcwd_device);
384 }
385 return len;
386}
387
388static long usb_pcwd_ioctl(struct file *file, unsigned int cmd,
389 unsigned long arg)
390{
391 void __user *argp = (void __user *)arg;
392 int __user *p = argp;
393 static const struct watchdog_info ident = {
394 .options = WDIOF_KEEPALIVEPING |
395 WDIOF_SETTIMEOUT |
396 WDIOF_MAGICCLOSE,
397 .firmware_version = 1,
398 .identity = DRIVER_NAME,
399 };
400
401 switch (cmd) {
402 case WDIOC_GETSUPPORT:
403 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
404
405 case WDIOC_GETSTATUS:
406 case WDIOC_GETBOOTSTATUS:
407 return put_user(0, p);
408
409 case WDIOC_GETTEMP:
410 {
411 int temperature;
412
413 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
414 return -EFAULT;
415
416 return put_user(temperature, p);
417 }
418
419 case WDIOC_SETOPTIONS:
420 {
421 int new_options, retval = -EINVAL;
422
423 if (get_user(new_options, p))
424 return -EFAULT;
425
426 if (new_options & WDIOS_DISABLECARD) {
427 usb_pcwd_stop(usb_pcwd_device);
428 retval = 0;
429 }
430
431 if (new_options & WDIOS_ENABLECARD) {
432 usb_pcwd_start(usb_pcwd_device);
433 retval = 0;
434 }
435
436 return retval;
437 }
438
439 case WDIOC_KEEPALIVE:
440 usb_pcwd_keepalive(usb_pcwd_device);
441 return 0;
442
443 case WDIOC_SETTIMEOUT:
444 {
445 int new_heartbeat;
446
447 if (get_user(new_heartbeat, p))
448 return -EFAULT;
449
450 if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
451 return -EINVAL;
452
453 usb_pcwd_keepalive(usb_pcwd_device);
454 }
455 fallthrough;
456
457 case WDIOC_GETTIMEOUT:
458 return put_user(heartbeat, p);
459
460 case WDIOC_GETTIMELEFT:
461 {
462 int time_left;
463
464 if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left))
465 return -EFAULT;
466
467 return put_user(time_left, p);
468 }
469
470 default:
471 return -ENOTTY;
472 }
473}
474
475static int usb_pcwd_open(struct inode *inode, struct file *file)
476{
477 /* /dev/watchdog can only be opened once */
478 if (test_and_set_bit(0, &is_active))
479 return -EBUSY;
480
481 /* Activate */
482 usb_pcwd_start(usb_pcwd_device);
483 usb_pcwd_keepalive(usb_pcwd_device);
484 return stream_open(inode, file);
485}
486
487static int usb_pcwd_release(struct inode *inode, struct file *file)
488{
489 /*
490 * Shut off the timer.
491 */
492 if (expect_release == 42) {
493 usb_pcwd_stop(usb_pcwd_device);
494 } else {
495 pr_crit("Unexpected close, not stopping watchdog!\n");
496 usb_pcwd_keepalive(usb_pcwd_device);
497 }
498 expect_release = 0;
499 clear_bit(0, &is_active);
500 return 0;
501}
502
503/*
504 * /dev/temperature handling
505 */
506
507static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
508 size_t len, loff_t *ppos)
509{
510 int temperature;
511
512 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
513 return -EFAULT;
514
515 if (copy_to_user(data, &temperature, 1))
516 return -EFAULT;
517
518 return 1;
519}
520
521static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
522{
523 return stream_open(inode, file);
524}
525
526static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
527{
528 return 0;
529}
530
531/*
532 * Notify system
533 */
534
535static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code,
536 void *unused)
537{
538 if (code == SYS_DOWN || code == SYS_HALT)
539 usb_pcwd_stop(usb_pcwd_device); /* Turn the WDT off */
540
541 return NOTIFY_DONE;
542}
543
544/*
545 * Kernel Interfaces
546 */
547
548static const struct file_operations usb_pcwd_fops = {
549 .owner = THIS_MODULE,
550 .llseek = no_llseek,
551 .write = usb_pcwd_write,
552 .unlocked_ioctl = usb_pcwd_ioctl,
553 .compat_ioctl = compat_ptr_ioctl,
554 .open = usb_pcwd_open,
555 .release = usb_pcwd_release,
556};
557
558static struct miscdevice usb_pcwd_miscdev = {
559 .minor = WATCHDOG_MINOR,
560 .name = "watchdog",
561 .fops = &usb_pcwd_fops,
562};
563
564static const struct file_operations usb_pcwd_temperature_fops = {
565 .owner = THIS_MODULE,
566 .llseek = no_llseek,
567 .read = usb_pcwd_temperature_read,
568 .open = usb_pcwd_temperature_open,
569 .release = usb_pcwd_temperature_release,
570};
571
572static struct miscdevice usb_pcwd_temperature_miscdev = {
573 .minor = TEMP_MINOR,
574 .name = "temperature",
575 .fops = &usb_pcwd_temperature_fops,
576};
577
578static struct notifier_block usb_pcwd_notifier = {
579 .notifier_call = usb_pcwd_notify_sys,
580};
581
582/**
583 * usb_pcwd_delete
584 */
585static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd)
586{
587 usb_free_urb(usb_pcwd->intr_urb);
588 usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size,
589 usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
590 kfree(usb_pcwd);
591}
592
593/**
594 * usb_pcwd_probe
595 *
596 * Called by the usb core when a new device is connected that it thinks
597 * this driver might be interested in.
598 */
599static int usb_pcwd_probe(struct usb_interface *interface,
600 const struct usb_device_id *id)
601{
602 struct usb_device *udev = interface_to_usbdev(interface);
603 struct usb_host_interface *iface_desc;
604 struct usb_endpoint_descriptor *endpoint;
605 struct usb_pcwd_private *usb_pcwd = NULL;
606 int pipe;
607 int retval = -ENOMEM;
608 int got_fw_rev;
609 unsigned char fw_rev_major, fw_rev_minor;
610 char fw_ver_str[20];
611 unsigned char option_switches, dummy;
612
613 cards_found++;
614 if (cards_found > 1) {
615 pr_err("This driver only supports 1 device\n");
616 return -ENODEV;
617 }
618
619 /* get the active interface descriptor */
620 iface_desc = interface->cur_altsetting;
621
622 /* check out that we have a HID device */
623 if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
624 pr_err("The device isn't a Human Interface Device\n");
625 return -ENODEV;
626 }
627
628 if (iface_desc->desc.bNumEndpoints < 1)
629 return -ENODEV;
630
631 /* check out the endpoint: it has to be Interrupt & IN */
632 endpoint = &iface_desc->endpoint[0].desc;
633
634 if (!usb_endpoint_is_int_in(endpoint)) {
635 /* we didn't find a Interrupt endpoint with direction IN */
636 pr_err("Couldn't find an INTR & IN endpoint\n");
637 return -ENODEV;
638 }
639
640 /* get a handle to the interrupt data pipe */
641 pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
642
643 /* allocate memory for our device and initialize it */
644 usb_pcwd = kzalloc(sizeof(struct usb_pcwd_private), GFP_KERNEL);
645 if (usb_pcwd == NULL)
646 goto error;
647
648 usb_pcwd_device = usb_pcwd;
649
650 mutex_init(&usb_pcwd->mtx);
651 usb_pcwd->udev = udev;
652 usb_pcwd->interface = interface;
653 usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
654 usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ?
655 le16_to_cpu(endpoint->wMaxPacketSize) : 8);
656
657 /* set up the memory buffer's */
658 usb_pcwd->intr_buffer = usb_alloc_coherent(udev, usb_pcwd->intr_size,
659 GFP_ATOMIC, &usb_pcwd->intr_dma);
660 if (!usb_pcwd->intr_buffer) {
661 pr_err("Out of memory\n");
662 goto error;
663 }
664
665 /* allocate the urb's */
666 usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
667 if (!usb_pcwd->intr_urb)
668 goto error;
669
670 /* initialise the intr urb's */
671 usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
672 usb_pcwd->intr_buffer, usb_pcwd->intr_size,
673 usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
674 usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
675 usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
676
677 /* register our interrupt URB with the USB system */
678 if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
679 pr_err("Problem registering interrupt URB\n");
680 retval = -EIO; /* failure */
681 goto error;
682 }
683
684 /* The device exists and can be communicated with */
685 usb_pcwd->exists = 1;
686
687 /* disable card */
688 usb_pcwd_stop(usb_pcwd);
689
690 /* Get the Firmware Version */
691 got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION,
692 &fw_rev_major, &fw_rev_minor);
693 if (got_fw_rev)
694 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
695 else
696 sprintf(fw_ver_str, "<card no answer>");
697
698 pr_info("Found card (Firmware: %s) with temp option\n", fw_ver_str);
699
700 /* Get switch settings */
701 usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy,
702 &option_switches);
703
704 pr_info("Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
705 option_switches,
706 ((option_switches & 0x10) ? "ON" : "OFF"),
707 ((option_switches & 0x08) ? "ON" : "OFF"));
708
709 /* If heartbeat = 0 then we use the heartbeat from the dip-switches */
710 if (heartbeat == 0)
711 heartbeat = heartbeat_tbl[(option_switches & 0x07)];
712
713 /* Check that the heartbeat value is within it's range ;
714 * if not reset to the default */
715 if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
716 usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
717 pr_info("heartbeat value must be 0<heartbeat<65536, using %d\n",
718 WATCHDOG_HEARTBEAT);
719 }
720
721 retval = register_reboot_notifier(&usb_pcwd_notifier);
722 if (retval != 0) {
723 pr_err("cannot register reboot notifier (err=%d)\n", retval);
724 goto error;
725 }
726
727 retval = misc_register(&usb_pcwd_temperature_miscdev);
728 if (retval != 0) {
729 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
730 TEMP_MINOR, retval);
731 goto err_out_unregister_reboot;
732 }
733
734 retval = misc_register(&usb_pcwd_miscdev);
735 if (retval != 0) {
736 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
737 WATCHDOG_MINOR, retval);
738 goto err_out_misc_deregister;
739 }
740
741 /* we can register the device now, as it is ready */
742 usb_set_intfdata(interface, usb_pcwd);
743
744 pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
745 heartbeat, nowayout);
746
747 return 0;
748
749err_out_misc_deregister:
750 misc_deregister(&usb_pcwd_temperature_miscdev);
751err_out_unregister_reboot:
752 unregister_reboot_notifier(&usb_pcwd_notifier);
753error:
754 if (usb_pcwd)
755 usb_pcwd_delete(usb_pcwd);
756 usb_pcwd_device = NULL;
757 return retval;
758}
759
760
761/**
762 * usb_pcwd_disconnect
763 *
764 * Called by the usb core when the device is removed from the system.
765 *
766 * This routine guarantees that the driver will not submit any more urbs
767 * by clearing dev->udev.
768 */
769static void usb_pcwd_disconnect(struct usb_interface *interface)
770{
771 struct usb_pcwd_private *usb_pcwd;
772
773 /* prevent races with open() */
774 mutex_lock(&disconnect_mutex);
775
776 usb_pcwd = usb_get_intfdata(interface);
777 usb_set_intfdata(interface, NULL);
778
779 mutex_lock(&usb_pcwd->mtx);
780
781 /* Stop the timer before we leave */
782 if (!nowayout)
783 usb_pcwd_stop(usb_pcwd);
784
785 /* We should now stop communicating with the USB PCWD device */
786 usb_pcwd->exists = 0;
787
788 /* Deregister */
789 misc_deregister(&usb_pcwd_miscdev);
790 misc_deregister(&usb_pcwd_temperature_miscdev);
791 unregister_reboot_notifier(&usb_pcwd_notifier);
792
793 mutex_unlock(&usb_pcwd->mtx);
794
795 /* Delete the USB PCWD device */
796 usb_pcwd_delete(usb_pcwd);
797
798 cards_found--;
799
800 mutex_unlock(&disconnect_mutex);
801
802 pr_info("USB PC Watchdog disconnected\n");
803}
804
805module_usb_driver(usb_pcwd_driver);