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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 = 0x00;
329 unsigned char lsb = 0x00;
330
331 usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
332
333 /*
334 * Convert celsius to fahrenheit, since this was
335 * the decided 'standard' for this return value.
336 */
337 *temperature = (lsb * 9 / 5) + 32;
338
339 return 0;
340}
341
342static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd,
343 int *time_left)
344{
345 unsigned char msb = 0x00;
346 unsigned char lsb = 0x00;
347
348 /* Read the time that's left before rebooting */
349 /* Note: if the board is not yet armed then we will read 0xFFFF */
350 usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
351
352 *time_left = (msb << 8) + lsb;
353
354 return 0;
355}
356
357/*
358 * /dev/watchdog handling
359 */
360
361static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
362 size_t len, loff_t *ppos)
363{
364 /* See if we got the magic character 'V' and reload the timer */
365 if (len) {
366 if (!nowayout) {
367 size_t i;
368
369 /* note: just in case someone wrote the magic character
370 * five months ago... */
371 expect_release = 0;
372
373 /* scan to see whether or not we got the
374 * magic character */
375 for (i = 0; i != len; i++) {
376 char c;
377 if (get_user(c, data + i))
378 return -EFAULT;
379 if (c == 'V')
380 expect_release = 42;
381 }
382 }
383
384 /* someone wrote to us, we should reload the timer */
385 usb_pcwd_keepalive(usb_pcwd_device);
386 }
387 return len;
388}
389
390static long usb_pcwd_ioctl(struct file *file, unsigned int cmd,
391 unsigned long arg)
392{
393 void __user *argp = (void __user *)arg;
394 int __user *p = argp;
395 static const struct watchdog_info ident = {
396 .options = WDIOF_KEEPALIVEPING |
397 WDIOF_SETTIMEOUT |
398 WDIOF_MAGICCLOSE,
399 .firmware_version = 1,
400 .identity = DRIVER_NAME,
401 };
402
403 switch (cmd) {
404 case WDIOC_GETSUPPORT:
405 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
406
407 case WDIOC_GETSTATUS:
408 case WDIOC_GETBOOTSTATUS:
409 return put_user(0, p);
410
411 case WDIOC_GETTEMP:
412 {
413 int temperature;
414
415 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
416 return -EFAULT;
417
418 return put_user(temperature, p);
419 }
420
421 case WDIOC_SETOPTIONS:
422 {
423 int new_options, retval = -EINVAL;
424
425 if (get_user(new_options, p))
426 return -EFAULT;
427
428 if (new_options & WDIOS_DISABLECARD) {
429 usb_pcwd_stop(usb_pcwd_device);
430 retval = 0;
431 }
432
433 if (new_options & WDIOS_ENABLECARD) {
434 usb_pcwd_start(usb_pcwd_device);
435 retval = 0;
436 }
437
438 return retval;
439 }
440
441 case WDIOC_KEEPALIVE:
442 usb_pcwd_keepalive(usb_pcwd_device);
443 return 0;
444
445 case WDIOC_SETTIMEOUT:
446 {
447 int new_heartbeat;
448
449 if (get_user(new_heartbeat, p))
450 return -EFAULT;
451
452 if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
453 return -EINVAL;
454
455 usb_pcwd_keepalive(usb_pcwd_device);
456 }
457 fallthrough;
458
459 case WDIOC_GETTIMEOUT:
460 return put_user(heartbeat, p);
461
462 case WDIOC_GETTIMELEFT:
463 {
464 int time_left;
465
466 if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left))
467 return -EFAULT;
468
469 return put_user(time_left, p);
470 }
471
472 default:
473 return -ENOTTY;
474 }
475}
476
477static int usb_pcwd_open(struct inode *inode, struct file *file)
478{
479 /* /dev/watchdog can only be opened once */
480 if (test_and_set_bit(0, &is_active))
481 return -EBUSY;
482
483 /* Activate */
484 usb_pcwd_start(usb_pcwd_device);
485 usb_pcwd_keepalive(usb_pcwd_device);
486 return stream_open(inode, file);
487}
488
489static int usb_pcwd_release(struct inode *inode, struct file *file)
490{
491 /*
492 * Shut off the timer.
493 */
494 if (expect_release == 42) {
495 usb_pcwd_stop(usb_pcwd_device);
496 } else {
497 pr_crit("Unexpected close, not stopping watchdog!\n");
498 usb_pcwd_keepalive(usb_pcwd_device);
499 }
500 expect_release = 0;
501 clear_bit(0, &is_active);
502 return 0;
503}
504
505/*
506 * /dev/temperature handling
507 */
508
509static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
510 size_t len, loff_t *ppos)
511{
512 int temperature;
513
514 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
515 return -EFAULT;
516
517 if (copy_to_user(data, &temperature, 1))
518 return -EFAULT;
519
520 return 1;
521}
522
523static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
524{
525 return stream_open(inode, file);
526}
527
528static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
529{
530 return 0;
531}
532
533/*
534 * Notify system
535 */
536
537static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code,
538 void *unused)
539{
540 if (code == SYS_DOWN || code == SYS_HALT)
541 usb_pcwd_stop(usb_pcwd_device); /* Turn the WDT off */
542
543 return NOTIFY_DONE;
544}
545
546/*
547 * Kernel Interfaces
548 */
549
550static const struct file_operations usb_pcwd_fops = {
551 .owner = THIS_MODULE,
552 .llseek = no_llseek,
553 .write = usb_pcwd_write,
554 .unlocked_ioctl = usb_pcwd_ioctl,
555 .compat_ioctl = compat_ptr_ioctl,
556 .open = usb_pcwd_open,
557 .release = usb_pcwd_release,
558};
559
560static struct miscdevice usb_pcwd_miscdev = {
561 .minor = WATCHDOG_MINOR,
562 .name = "watchdog",
563 .fops = &usb_pcwd_fops,
564};
565
566static const struct file_operations usb_pcwd_temperature_fops = {
567 .owner = THIS_MODULE,
568 .llseek = no_llseek,
569 .read = usb_pcwd_temperature_read,
570 .open = usb_pcwd_temperature_open,
571 .release = usb_pcwd_temperature_release,
572};
573
574static struct miscdevice usb_pcwd_temperature_miscdev = {
575 .minor = TEMP_MINOR,
576 .name = "temperature",
577 .fops = &usb_pcwd_temperature_fops,
578};
579
580static struct notifier_block usb_pcwd_notifier = {
581 .notifier_call = usb_pcwd_notify_sys,
582};
583
584/**
585 * usb_pcwd_delete
586 */
587static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd)
588{
589 usb_free_urb(usb_pcwd->intr_urb);
590 usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size,
591 usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
592 kfree(usb_pcwd);
593}
594
595/**
596 * usb_pcwd_probe
597 *
598 * Called by the usb core when a new device is connected that it thinks
599 * this driver might be interested in.
600 */
601static int usb_pcwd_probe(struct usb_interface *interface,
602 const struct usb_device_id *id)
603{
604 struct usb_device *udev = interface_to_usbdev(interface);
605 struct usb_host_interface *iface_desc;
606 struct usb_endpoint_descriptor *endpoint;
607 struct usb_pcwd_private *usb_pcwd = NULL;
608 int pipe;
609 int retval = -ENOMEM;
610 int got_fw_rev;
611 unsigned char fw_rev_major, fw_rev_minor;
612 char fw_ver_str[20];
613 unsigned char option_switches, dummy;
614
615 cards_found++;
616 if (cards_found > 1) {
617 pr_err("This driver only supports 1 device\n");
618 return -ENODEV;
619 }
620
621 /* get the active interface descriptor */
622 iface_desc = interface->cur_altsetting;
623
624 /* check out that we have a HID device */
625 if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
626 pr_err("The device isn't a Human Interface Device\n");
627 return -ENODEV;
628 }
629
630 if (iface_desc->desc.bNumEndpoints < 1)
631 return -ENODEV;
632
633 /* check out the endpoint: it has to be Interrupt & IN */
634 endpoint = &iface_desc->endpoint[0].desc;
635
636 if (!usb_endpoint_is_int_in(endpoint)) {
637 /* we didn't find a Interrupt endpoint with direction IN */
638 pr_err("Couldn't find an INTR & IN endpoint\n");
639 return -ENODEV;
640 }
641
642 /* get a handle to the interrupt data pipe */
643 pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
644
645 /* allocate memory for our device and initialize it */
646 usb_pcwd = kzalloc(sizeof(struct usb_pcwd_private), GFP_KERNEL);
647 if (usb_pcwd == NULL)
648 goto error;
649
650 usb_pcwd_device = usb_pcwd;
651
652 mutex_init(&usb_pcwd->mtx);
653 usb_pcwd->udev = udev;
654 usb_pcwd->interface = interface;
655 usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
656 usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ?
657 le16_to_cpu(endpoint->wMaxPacketSize) : 8);
658
659 /* set up the memory buffer's */
660 usb_pcwd->intr_buffer = usb_alloc_coherent(udev, usb_pcwd->intr_size,
661 GFP_KERNEL, &usb_pcwd->intr_dma);
662 if (!usb_pcwd->intr_buffer) {
663 pr_err("Out of memory\n");
664 goto error;
665 }
666
667 /* allocate the urb's */
668 usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
669 if (!usb_pcwd->intr_urb)
670 goto error;
671
672 /* initialise the intr urb's */
673 usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
674 usb_pcwd->intr_buffer, usb_pcwd->intr_size,
675 usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
676 usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
677 usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
678
679 /* register our interrupt URB with the USB system */
680 if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
681 pr_err("Problem registering interrupt URB\n");
682 retval = -EIO; /* failure */
683 goto error;
684 }
685
686 /* The device exists and can be communicated with */
687 usb_pcwd->exists = 1;
688
689 /* disable card */
690 usb_pcwd_stop(usb_pcwd);
691
692 /* Get the Firmware Version */
693 got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION,
694 &fw_rev_major, &fw_rev_minor);
695 if (got_fw_rev)
696 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
697 else
698 sprintf(fw_ver_str, "<card no answer>");
699
700 pr_info("Found card (Firmware: %s) with temp option\n", fw_ver_str);
701
702 /* Get switch settings */
703 usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy,
704 &option_switches);
705
706 pr_info("Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
707 option_switches,
708 ((option_switches & 0x10) ? "ON" : "OFF"),
709 ((option_switches & 0x08) ? "ON" : "OFF"));
710
711 /* If heartbeat = 0 then we use the heartbeat from the dip-switches */
712 if (heartbeat == 0)
713 heartbeat = heartbeat_tbl[(option_switches & 0x07)];
714
715 /* Check that the heartbeat value is within it's range ;
716 * if not reset to the default */
717 if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
718 usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
719 pr_info("heartbeat value must be 0<heartbeat<65536, using %d\n",
720 WATCHDOG_HEARTBEAT);
721 }
722
723 retval = register_reboot_notifier(&usb_pcwd_notifier);
724 if (retval != 0) {
725 pr_err("cannot register reboot notifier (err=%d)\n", retval);
726 goto error;
727 }
728
729 retval = misc_register(&usb_pcwd_temperature_miscdev);
730 if (retval != 0) {
731 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
732 TEMP_MINOR, retval);
733 goto err_out_unregister_reboot;
734 }
735
736 retval = misc_register(&usb_pcwd_miscdev);
737 if (retval != 0) {
738 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
739 WATCHDOG_MINOR, retval);
740 goto err_out_misc_deregister;
741 }
742
743 /* we can register the device now, as it is ready */
744 usb_set_intfdata(interface, usb_pcwd);
745
746 pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
747 heartbeat, nowayout);
748
749 return 0;
750
751err_out_misc_deregister:
752 misc_deregister(&usb_pcwd_temperature_miscdev);
753err_out_unregister_reboot:
754 unregister_reboot_notifier(&usb_pcwd_notifier);
755error:
756 if (usb_pcwd)
757 usb_pcwd_delete(usb_pcwd);
758 usb_pcwd_device = NULL;
759 return retval;
760}
761
762
763/**
764 * usb_pcwd_disconnect
765 *
766 * Called by the usb core when the device is removed from the system.
767 *
768 * This routine guarantees that the driver will not submit any more urbs
769 * by clearing dev->udev.
770 */
771static void usb_pcwd_disconnect(struct usb_interface *interface)
772{
773 struct usb_pcwd_private *usb_pcwd;
774
775 /* prevent races with open() */
776 mutex_lock(&disconnect_mutex);
777
778 usb_pcwd = usb_get_intfdata(interface);
779 usb_set_intfdata(interface, NULL);
780
781 mutex_lock(&usb_pcwd->mtx);
782
783 /* Stop the timer before we leave */
784 if (!nowayout)
785 usb_pcwd_stop(usb_pcwd);
786
787 /* We should now stop communicating with the USB PCWD device */
788 usb_pcwd->exists = 0;
789
790 /* Deregister */
791 misc_deregister(&usb_pcwd_miscdev);
792 misc_deregister(&usb_pcwd_temperature_miscdev);
793 unregister_reboot_notifier(&usb_pcwd_notifier);
794
795 mutex_unlock(&usb_pcwd->mtx);
796
797 /* Delete the USB PCWD device */
798 usb_pcwd_delete(usb_pcwd);
799
800 cards_found--;
801
802 mutex_unlock(&disconnect_mutex);
803
804 pr_info("USB PC Watchdog disconnected\n");
805}
806
807module_usb_driver(usb_pcwd_driver);
1/*
2 * Berkshire USB-PC Watchdog Card Driver
3 *
4 * (c) Copyright 2004-2007 Wim Van Sebroeck <wim@iguana.be>.
5 *
6 * Based on source code of the following authors:
7 * Ken Hollis <kenji@bitgate.com>,
8 * Alan Cox <alan@lxorguk.ukuu.org.uk>,
9 * Matt Domsch <Matt_Domsch@dell.com>,
10 * Rob Radez <rob@osinvestor.com>,
11 * Greg Kroah-Hartman <greg@kroah.com>
12 *
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version
16 * 2 of the License, or (at your option) any later version.
17 *
18 * Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
19 * provide warranty for any of this software. This material is
20 * provided "AS-IS" and at no charge.
21 *
22 * Thanks also to Simon Machell at Berkshire Products Inc. for
23 * providing the test hardware. More info is available at
24 * http://www.berkprod.com/ or http://www.pcwatchdog.com/
25 */
26
27#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
28
29#include <linux/module.h> /* For module specific items */
30#include <linux/moduleparam.h> /* For new moduleparam's */
31#include <linux/types.h> /* For standard types (like size_t) */
32#include <linux/errno.h> /* For the -ENODEV/... values */
33#include <linux/kernel.h> /* For printk/panic/... */
34#include <linux/delay.h> /* For mdelay function */
35#include <linux/miscdevice.h> /* For MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR) */
36#include <linux/watchdog.h> /* For the watchdog specific items */
37#include <linux/notifier.h> /* For notifier support */
38#include <linux/reboot.h> /* For reboot_notifier stuff */
39#include <linux/init.h> /* For __init/__exit/... */
40#include <linux/fs.h> /* For file operations */
41#include <linux/usb.h> /* For USB functions */
42#include <linux/slab.h> /* For kmalloc, ... */
43#include <linux/mutex.h> /* For mutex locking */
44#include <linux/hid.h> /* For HID_REQ_SET_REPORT & HID_DT_REPORT */
45#include <linux/uaccess.h> /* For copy_to_user/put_user/... */
46
47#ifdef CONFIG_USB_DEBUG
48static int debug = 1;
49#else
50static int debug;
51#endif
52
53/* Use our own dbg macro */
54
55#undef dbg
56#ifndef DEBUG
57#define DEBUG
58#endif
59#define dbg(format, ...) \
60do { \
61 if (debug) \
62 pr_debug(format "\n", ##__VA_ARGS__); \
63} while (0)
64
65/* Module and Version Information */
66#define DRIVER_VERSION "1.02"
67#define DRIVER_AUTHOR "Wim Van Sebroeck <wim@iguana.be>"
68#define DRIVER_DESC "Berkshire USB-PC Watchdog driver"
69#define DRIVER_LICENSE "GPL"
70#define DRIVER_NAME "pcwd_usb"
71
72MODULE_AUTHOR(DRIVER_AUTHOR);
73MODULE_DESCRIPTION(DRIVER_DESC);
74MODULE_LICENSE(DRIVER_LICENSE);
75MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
76MODULE_ALIAS_MISCDEV(TEMP_MINOR);
77
78/* Module Parameters */
79module_param(debug, int, 0);
80MODULE_PARM_DESC(debug, "Debug enabled or not");
81
82#define WATCHDOG_HEARTBEAT 0 /* default heartbeat =
83 delay-time from dip-switches */
84static int heartbeat = WATCHDOG_HEARTBEAT;
85module_param(heartbeat, int, 0);
86MODULE_PARM_DESC(heartbeat, "Watchdog heartbeat in seconds. "
87 "(0<heartbeat<65536 or 0=delay-time from dip-switches, default="
88 __MODULE_STRING(WATCHDOG_HEARTBEAT) ")");
89
90static bool nowayout = WATCHDOG_NOWAYOUT;
91module_param(nowayout, bool, 0);
92MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
93 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
94
95/* The vendor and product id's for the USB-PC Watchdog card */
96#define USB_PCWD_VENDOR_ID 0x0c98
97#define USB_PCWD_PRODUCT_ID 0x1140
98
99/* table of devices that work with this driver */
100static struct usb_device_id usb_pcwd_table[] = {
101 { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) },
102 { } /* Terminating entry */
103};
104MODULE_DEVICE_TABLE(usb, usb_pcwd_table);
105
106/* according to documentation max. time to process a command for the USB
107 * watchdog card is 100 or 200 ms, so we give it 250 ms to do it's job */
108#define USB_COMMAND_TIMEOUT 250
109
110/* Watchdog's internal commands */
111#define CMD_READ_TEMP 0x02 /* Read Temperature;
112 Re-trigger Watchdog */
113#define CMD_TRIGGER CMD_READ_TEMP
114#define CMD_GET_STATUS 0x04 /* Get Status Information */
115#define CMD_GET_FIRMWARE_VERSION 0x08 /* Get Firmware Version */
116#define CMD_GET_DIP_SWITCH_SETTINGS 0x0c /* Get Dip Switch Settings */
117#define CMD_READ_WATCHDOG_TIMEOUT 0x18 /* Read Current Watchdog Time */
118#define CMD_WRITE_WATCHDOG_TIMEOUT 0x19 /* Write Current WatchdogTime */
119#define CMD_ENABLE_WATCHDOG 0x30 /* Enable / Disable Watchdog */
120#define CMD_DISABLE_WATCHDOG CMD_ENABLE_WATCHDOG
121
122/* Watchdog's Dip Switch heartbeat values */
123static const int heartbeat_tbl[] = {
124 5, /* OFF-OFF-OFF = 5 Sec */
125 10, /* OFF-OFF-ON = 10 Sec */
126 30, /* OFF-ON-OFF = 30 Sec */
127 60, /* OFF-ON-ON = 1 Min */
128 300, /* ON-OFF-OFF = 5 Min */
129 600, /* ON-OFF-ON = 10 Min */
130 1800, /* ON-ON-OFF = 30 Min */
131 3600, /* ON-ON-ON = 1 hour */
132};
133
134/* We can only use 1 card due to the /dev/watchdog restriction */
135static int cards_found;
136
137/* some internal variables */
138static unsigned long is_active;
139static char expect_release;
140
141/* Structure to hold all of our device specific stuff */
142struct usb_pcwd_private {
143 /* save off the usb device pointer */
144 struct usb_device *udev;
145 /* the interface for this device */
146 struct usb_interface *interface;
147
148 /* the interface number used for cmd's */
149 unsigned int interface_number;
150
151 /* the buffer to intr data */
152 unsigned char *intr_buffer;
153 /* the dma address for the intr buffer */
154 dma_addr_t intr_dma;
155 /* the size of the intr buffer */
156 size_t intr_size;
157 /* the urb used for the intr pipe */
158 struct urb *intr_urb;
159
160 /* The command that is reported back */
161 unsigned char cmd_command;
162 /* The data MSB that is reported back */
163 unsigned char cmd_data_msb;
164 /* The data LSB that is reported back */
165 unsigned char cmd_data_lsb;
166 /* true if we received a report after a command */
167 atomic_t cmd_received;
168
169 /* Wether or not the device exists */
170 int exists;
171 /* locks this structure */
172 struct mutex mtx;
173};
174static struct usb_pcwd_private *usb_pcwd_device;
175
176/* prevent races between open() and disconnect() */
177static DEFINE_MUTEX(disconnect_mutex);
178
179/* local function prototypes */
180static int usb_pcwd_probe(struct usb_interface *interface,
181 const struct usb_device_id *id);
182static void usb_pcwd_disconnect(struct usb_interface *interface);
183
184/* usb specific object needed to register this driver with the usb subsystem */
185static struct usb_driver usb_pcwd_driver = {
186 .name = DRIVER_NAME,
187 .probe = usb_pcwd_probe,
188 .disconnect = usb_pcwd_disconnect,
189 .id_table = usb_pcwd_table,
190};
191
192
193static void usb_pcwd_intr_done(struct urb *urb)
194{
195 struct usb_pcwd_private *usb_pcwd =
196 (struct usb_pcwd_private *)urb->context;
197 unsigned char *data = usb_pcwd->intr_buffer;
198 int retval;
199
200 switch (urb->status) {
201 case 0: /* success */
202 break;
203 case -ECONNRESET: /* unlink */
204 case -ENOENT:
205 case -ESHUTDOWN:
206 /* this urb is terminated, clean up */
207 dbg("%s - urb shutting down with status: %d", __func__,
208 urb->status);
209 return;
210 /* -EPIPE: should clear the halt */
211 default: /* error */
212 dbg("%s - nonzero urb status received: %d", __func__,
213 urb->status);
214 goto resubmit;
215 }
216
217 dbg("received following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
218 data[0], data[1], data[2]);
219
220 usb_pcwd->cmd_command = data[0];
221 usb_pcwd->cmd_data_msb = data[1];
222 usb_pcwd->cmd_data_lsb = data[2];
223
224 /* notify anyone waiting that the cmd has finished */
225 atomic_set(&usb_pcwd->cmd_received, 1);
226
227resubmit:
228 retval = usb_submit_urb(urb, GFP_ATOMIC);
229 if (retval)
230 pr_err("can't resubmit intr, usb_submit_urb failed with result %d\n",
231 retval);
232}
233
234static int usb_pcwd_send_command(struct usb_pcwd_private *usb_pcwd,
235 unsigned char cmd, unsigned char *msb, unsigned char *lsb)
236{
237 int got_response, count;
238 unsigned char buf[6];
239
240 /* We will not send any commands if the USB PCWD device does
241 * not exist */
242 if ((!usb_pcwd) || (!usb_pcwd->exists))
243 return -1;
244
245 /* The USB PC Watchdog uses a 6 byte report format.
246 * The board currently uses only 3 of the six bytes of the report. */
247 buf[0] = cmd; /* Byte 0 = CMD */
248 buf[1] = *msb; /* Byte 1 = Data MSB */
249 buf[2] = *lsb; /* Byte 2 = Data LSB */
250 buf[3] = buf[4] = buf[5] = 0; /* All other bytes not used */
251
252 dbg("sending following data cmd=0x%02x msb=0x%02x lsb=0x%02x",
253 buf[0], buf[1], buf[2]);
254
255 atomic_set(&usb_pcwd->cmd_received, 0);
256
257 if (usb_control_msg(usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0),
258 HID_REQ_SET_REPORT, HID_DT_REPORT,
259 0x0200, usb_pcwd->interface_number, buf, sizeof(buf),
260 USB_COMMAND_TIMEOUT) != sizeof(buf)) {
261 dbg("usb_pcwd_send_command: error in usb_control_msg for "
262 "cmd 0x%x 0x%x 0x%x\n", cmd, *msb, *lsb);
263 }
264 /* wait till the usb card processed the command,
265 * with a max. timeout of USB_COMMAND_TIMEOUT */
266 got_response = 0;
267 for (count = 0; (count < USB_COMMAND_TIMEOUT) && (!got_response);
268 count++) {
269 mdelay(1);
270 if (atomic_read(&usb_pcwd->cmd_received))
271 got_response = 1;
272 }
273
274 if ((got_response) && (cmd == usb_pcwd->cmd_command)) {
275 /* read back response */
276 *msb = usb_pcwd->cmd_data_msb;
277 *lsb = usb_pcwd->cmd_data_lsb;
278 }
279
280 return got_response;
281}
282
283static int usb_pcwd_start(struct usb_pcwd_private *usb_pcwd)
284{
285 unsigned char msb = 0x00;
286 unsigned char lsb = 0x00;
287 int retval;
288
289 /* Enable Watchdog */
290 retval = usb_pcwd_send_command(usb_pcwd, CMD_ENABLE_WATCHDOG,
291 &msb, &lsb);
292
293 if ((retval == 0) || (lsb == 0)) {
294 pr_err("Card did not acknowledge enable attempt\n");
295 return -1;
296 }
297
298 return 0;
299}
300
301static int usb_pcwd_stop(struct usb_pcwd_private *usb_pcwd)
302{
303 unsigned char msb = 0xA5;
304 unsigned char lsb = 0xC3;
305 int retval;
306
307 /* Disable Watchdog */
308 retval = usb_pcwd_send_command(usb_pcwd, CMD_DISABLE_WATCHDOG,
309 &msb, &lsb);
310
311 if ((retval == 0) || (lsb != 0)) {
312 pr_err("Card did not acknowledge disable attempt\n");
313 return -1;
314 }
315
316 return 0;
317}
318
319static int usb_pcwd_keepalive(struct usb_pcwd_private *usb_pcwd)
320{
321 unsigned char dummy;
322
323 /* Re-trigger Watchdog */
324 usb_pcwd_send_command(usb_pcwd, CMD_TRIGGER, &dummy, &dummy);
325
326 return 0;
327}
328
329static int usb_pcwd_set_heartbeat(struct usb_pcwd_private *usb_pcwd, int t)
330{
331 unsigned char msb = t / 256;
332 unsigned char lsb = t % 256;
333
334 if ((t < 0x0001) || (t > 0xFFFF))
335 return -EINVAL;
336
337 /* Write new heartbeat to watchdog */
338 usb_pcwd_send_command(usb_pcwd, CMD_WRITE_WATCHDOG_TIMEOUT, &msb, &lsb);
339
340 heartbeat = t;
341 return 0;
342}
343
344static int usb_pcwd_get_temperature(struct usb_pcwd_private *usb_pcwd,
345 int *temperature)
346{
347 unsigned char msb, lsb;
348
349 usb_pcwd_send_command(usb_pcwd, CMD_READ_TEMP, &msb, &lsb);
350
351 /*
352 * Convert celsius to fahrenheit, since this was
353 * the decided 'standard' for this return value.
354 */
355 *temperature = (lsb * 9 / 5) + 32;
356
357 return 0;
358}
359
360static int usb_pcwd_get_timeleft(struct usb_pcwd_private *usb_pcwd,
361 int *time_left)
362{
363 unsigned char msb, lsb;
364
365 /* Read the time that's left before rebooting */
366 /* Note: if the board is not yet armed then we will read 0xFFFF */
367 usb_pcwd_send_command(usb_pcwd, CMD_READ_WATCHDOG_TIMEOUT, &msb, &lsb);
368
369 *time_left = (msb << 8) + lsb;
370
371 return 0;
372}
373
374/*
375 * /dev/watchdog handling
376 */
377
378static ssize_t usb_pcwd_write(struct file *file, const char __user *data,
379 size_t len, loff_t *ppos)
380{
381 /* See if we got the magic character 'V' and reload the timer */
382 if (len) {
383 if (!nowayout) {
384 size_t i;
385
386 /* note: just in case someone wrote the magic character
387 * five months ago... */
388 expect_release = 0;
389
390 /* scan to see whether or not we got the
391 * magic character */
392 for (i = 0; i != len; i++) {
393 char c;
394 if (get_user(c, data + i))
395 return -EFAULT;
396 if (c == 'V')
397 expect_release = 42;
398 }
399 }
400
401 /* someone wrote to us, we should reload the timer */
402 usb_pcwd_keepalive(usb_pcwd_device);
403 }
404 return len;
405}
406
407static long usb_pcwd_ioctl(struct file *file, unsigned int cmd,
408 unsigned long arg)
409{
410 void __user *argp = (void __user *)arg;
411 int __user *p = argp;
412 static const struct watchdog_info ident = {
413 .options = WDIOF_KEEPALIVEPING |
414 WDIOF_SETTIMEOUT |
415 WDIOF_MAGICCLOSE,
416 .firmware_version = 1,
417 .identity = DRIVER_NAME,
418 };
419
420 switch (cmd) {
421 case WDIOC_GETSUPPORT:
422 return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0;
423
424 case WDIOC_GETSTATUS:
425 case WDIOC_GETBOOTSTATUS:
426 return put_user(0, p);
427
428 case WDIOC_GETTEMP:
429 {
430 int temperature;
431
432 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
433 return -EFAULT;
434
435 return put_user(temperature, p);
436 }
437
438 case WDIOC_SETOPTIONS:
439 {
440 int new_options, retval = -EINVAL;
441
442 if (get_user(new_options, p))
443 return -EFAULT;
444
445 if (new_options & WDIOS_DISABLECARD) {
446 usb_pcwd_stop(usb_pcwd_device);
447 retval = 0;
448 }
449
450 if (new_options & WDIOS_ENABLECARD) {
451 usb_pcwd_start(usb_pcwd_device);
452 retval = 0;
453 }
454
455 return retval;
456 }
457
458 case WDIOC_KEEPALIVE:
459 usb_pcwd_keepalive(usb_pcwd_device);
460 return 0;
461
462 case WDIOC_SETTIMEOUT:
463 {
464 int new_heartbeat;
465
466 if (get_user(new_heartbeat, p))
467 return -EFAULT;
468
469 if (usb_pcwd_set_heartbeat(usb_pcwd_device, new_heartbeat))
470 return -EINVAL;
471
472 usb_pcwd_keepalive(usb_pcwd_device);
473 /* Fall */
474 }
475
476 case WDIOC_GETTIMEOUT:
477 return put_user(heartbeat, p);
478
479 case WDIOC_GETTIMELEFT:
480 {
481 int time_left;
482
483 if (usb_pcwd_get_timeleft(usb_pcwd_device, &time_left))
484 return -EFAULT;
485
486 return put_user(time_left, p);
487 }
488
489 default:
490 return -ENOTTY;
491 }
492}
493
494static int usb_pcwd_open(struct inode *inode, struct file *file)
495{
496 /* /dev/watchdog can only be opened once */
497 if (test_and_set_bit(0, &is_active))
498 return -EBUSY;
499
500 /* Activate */
501 usb_pcwd_start(usb_pcwd_device);
502 usb_pcwd_keepalive(usb_pcwd_device);
503 return nonseekable_open(inode, file);
504}
505
506static int usb_pcwd_release(struct inode *inode, struct file *file)
507{
508 /*
509 * Shut off the timer.
510 */
511 if (expect_release == 42) {
512 usb_pcwd_stop(usb_pcwd_device);
513 } else {
514 pr_crit("Unexpected close, not stopping watchdog!\n");
515 usb_pcwd_keepalive(usb_pcwd_device);
516 }
517 expect_release = 0;
518 clear_bit(0, &is_active);
519 return 0;
520}
521
522/*
523 * /dev/temperature handling
524 */
525
526static ssize_t usb_pcwd_temperature_read(struct file *file, char __user *data,
527 size_t len, loff_t *ppos)
528{
529 int temperature;
530
531 if (usb_pcwd_get_temperature(usb_pcwd_device, &temperature))
532 return -EFAULT;
533
534 if (copy_to_user(data, &temperature, 1))
535 return -EFAULT;
536
537 return 1;
538}
539
540static int usb_pcwd_temperature_open(struct inode *inode, struct file *file)
541{
542 return nonseekable_open(inode, file);
543}
544
545static int usb_pcwd_temperature_release(struct inode *inode, struct file *file)
546{
547 return 0;
548}
549
550/*
551 * Notify system
552 */
553
554static int usb_pcwd_notify_sys(struct notifier_block *this, unsigned long code,
555 void *unused)
556{
557 if (code == SYS_DOWN || code == SYS_HALT)
558 usb_pcwd_stop(usb_pcwd_device); /* Turn the WDT off */
559
560 return NOTIFY_DONE;
561}
562
563/*
564 * Kernel Interfaces
565 */
566
567static const struct file_operations usb_pcwd_fops = {
568 .owner = THIS_MODULE,
569 .llseek = no_llseek,
570 .write = usb_pcwd_write,
571 .unlocked_ioctl = usb_pcwd_ioctl,
572 .open = usb_pcwd_open,
573 .release = usb_pcwd_release,
574};
575
576static struct miscdevice usb_pcwd_miscdev = {
577 .minor = WATCHDOG_MINOR,
578 .name = "watchdog",
579 .fops = &usb_pcwd_fops,
580};
581
582static const struct file_operations usb_pcwd_temperature_fops = {
583 .owner = THIS_MODULE,
584 .llseek = no_llseek,
585 .read = usb_pcwd_temperature_read,
586 .open = usb_pcwd_temperature_open,
587 .release = usb_pcwd_temperature_release,
588};
589
590static struct miscdevice usb_pcwd_temperature_miscdev = {
591 .minor = TEMP_MINOR,
592 .name = "temperature",
593 .fops = &usb_pcwd_temperature_fops,
594};
595
596static struct notifier_block usb_pcwd_notifier = {
597 .notifier_call = usb_pcwd_notify_sys,
598};
599
600/**
601 * usb_pcwd_delete
602 */
603static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd)
604{
605 usb_free_urb(usb_pcwd->intr_urb);
606 if (usb_pcwd->intr_buffer != NULL)
607 usb_free_coherent(usb_pcwd->udev, usb_pcwd->intr_size,
608 usb_pcwd->intr_buffer, usb_pcwd->intr_dma);
609 kfree(usb_pcwd);
610}
611
612/**
613 * usb_pcwd_probe
614 *
615 * Called by the usb core when a new device is connected that it thinks
616 * this driver might be interested in.
617 */
618static int usb_pcwd_probe(struct usb_interface *interface,
619 const struct usb_device_id *id)
620{
621 struct usb_device *udev = interface_to_usbdev(interface);
622 struct usb_host_interface *iface_desc;
623 struct usb_endpoint_descriptor *endpoint;
624 struct usb_pcwd_private *usb_pcwd = NULL;
625 int pipe, maxp;
626 int retval = -ENOMEM;
627 int got_fw_rev;
628 unsigned char fw_rev_major, fw_rev_minor;
629 char fw_ver_str[20];
630 unsigned char option_switches, dummy;
631
632 cards_found++;
633 if (cards_found > 1) {
634 pr_err("This driver only supports 1 device\n");
635 return -ENODEV;
636 }
637
638 /* get the active interface descriptor */
639 iface_desc = interface->cur_altsetting;
640
641 /* check out that we have a HID device */
642 if (!(iface_desc->desc.bInterfaceClass == USB_CLASS_HID)) {
643 pr_err("The device isn't a Human Interface Device\n");
644 return -ENODEV;
645 }
646
647 /* check out the endpoint: it has to be Interrupt & IN */
648 endpoint = &iface_desc->endpoint[0].desc;
649
650 if (!usb_endpoint_is_int_in(endpoint)) {
651 /* we didn't find a Interrupt endpoint with direction IN */
652 pr_err("Couldn't find an INTR & IN endpoint\n");
653 return -ENODEV;
654 }
655
656 /* get a handle to the interrupt data pipe */
657 pipe = usb_rcvintpipe(udev, endpoint->bEndpointAddress);
658 maxp = usb_maxpacket(udev, pipe, usb_pipeout(pipe));
659
660 /* allocate memory for our device and initialize it */
661 usb_pcwd = kzalloc(sizeof(struct usb_pcwd_private), GFP_KERNEL);
662 if (usb_pcwd == NULL) {
663 pr_err("Out of memory\n");
664 goto error;
665 }
666
667 usb_pcwd_device = usb_pcwd;
668
669 mutex_init(&usb_pcwd->mtx);
670 usb_pcwd->udev = udev;
671 usb_pcwd->interface = interface;
672 usb_pcwd->interface_number = iface_desc->desc.bInterfaceNumber;
673 usb_pcwd->intr_size = (le16_to_cpu(endpoint->wMaxPacketSize) > 8 ?
674 le16_to_cpu(endpoint->wMaxPacketSize) : 8);
675
676 /* set up the memory buffer's */
677 usb_pcwd->intr_buffer = usb_alloc_coherent(udev, usb_pcwd->intr_size,
678 GFP_ATOMIC, &usb_pcwd->intr_dma);
679 if (!usb_pcwd->intr_buffer) {
680 pr_err("Out of memory\n");
681 goto error;
682 }
683
684 /* allocate the urb's */
685 usb_pcwd->intr_urb = usb_alloc_urb(0, GFP_KERNEL);
686 if (!usb_pcwd->intr_urb) {
687 pr_err("Out of memory\n");
688 goto error;
689 }
690
691 /* initialise the intr urb's */
692 usb_fill_int_urb(usb_pcwd->intr_urb, udev, pipe,
693 usb_pcwd->intr_buffer, usb_pcwd->intr_size,
694 usb_pcwd_intr_done, usb_pcwd, endpoint->bInterval);
695 usb_pcwd->intr_urb->transfer_dma = usb_pcwd->intr_dma;
696 usb_pcwd->intr_urb->transfer_flags |= URB_NO_TRANSFER_DMA_MAP;
697
698 /* register our interrupt URB with the USB system */
699 if (usb_submit_urb(usb_pcwd->intr_urb, GFP_KERNEL)) {
700 pr_err("Problem registering interrupt URB\n");
701 retval = -EIO; /* failure */
702 goto error;
703 }
704
705 /* The device exists and can be communicated with */
706 usb_pcwd->exists = 1;
707
708 /* disable card */
709 usb_pcwd_stop(usb_pcwd);
710
711 /* Get the Firmware Version */
712 got_fw_rev = usb_pcwd_send_command(usb_pcwd, CMD_GET_FIRMWARE_VERSION,
713 &fw_rev_major, &fw_rev_minor);
714 if (got_fw_rev)
715 sprintf(fw_ver_str, "%u.%02u", fw_rev_major, fw_rev_minor);
716 else
717 sprintf(fw_ver_str, "<card no answer>");
718
719 pr_info("Found card (Firmware: %s) with temp option\n", fw_ver_str);
720
721 /* Get switch settings */
722 usb_pcwd_send_command(usb_pcwd, CMD_GET_DIP_SWITCH_SETTINGS, &dummy,
723 &option_switches);
724
725 pr_info("Option switches (0x%02x): Temperature Reset Enable=%s, Power On Delay=%s\n",
726 option_switches,
727 ((option_switches & 0x10) ? "ON" : "OFF"),
728 ((option_switches & 0x08) ? "ON" : "OFF"));
729
730 /* If heartbeat = 0 then we use the heartbeat from the dip-switches */
731 if (heartbeat == 0)
732 heartbeat = heartbeat_tbl[(option_switches & 0x07)];
733
734 /* Check that the heartbeat value is within it's range ;
735 * if not reset to the default */
736 if (usb_pcwd_set_heartbeat(usb_pcwd, heartbeat)) {
737 usb_pcwd_set_heartbeat(usb_pcwd, WATCHDOG_HEARTBEAT);
738 pr_info("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 pr_err("cannot register reboot notifier (err=%d)\n", retval);
745 goto error;
746 }
747
748 retval = misc_register(&usb_pcwd_temperature_miscdev);
749 if (retval != 0) {
750 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
751 TEMP_MINOR, retval);
752 goto err_out_unregister_reboot;
753 }
754
755 retval = misc_register(&usb_pcwd_miscdev);
756 if (retval != 0) {
757 pr_err("cannot register miscdev on minor=%d (err=%d)\n",
758 WATCHDOG_MINOR, retval);
759 goto err_out_misc_deregister;
760 }
761
762 /* we can register the device now, as it is ready */
763 usb_set_intfdata(interface, usb_pcwd);
764
765 pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n",
766 heartbeat, nowayout);
767
768 return 0;
769
770err_out_misc_deregister:
771 misc_deregister(&usb_pcwd_temperature_miscdev);
772err_out_unregister_reboot:
773 unregister_reboot_notifier(&usb_pcwd_notifier);
774error:
775 if (usb_pcwd)
776 usb_pcwd_delete(usb_pcwd);
777 usb_pcwd_device = NULL;
778 return retval;
779}
780
781
782/**
783 * usb_pcwd_disconnect
784 *
785 * Called by the usb core when the device is removed from the system.
786 *
787 * This routine guarantees that the driver will not submit any more urbs
788 * by clearing dev->udev.
789 */
790static void usb_pcwd_disconnect(struct usb_interface *interface)
791{
792 struct usb_pcwd_private *usb_pcwd;
793
794 /* prevent races with open() */
795 mutex_lock(&disconnect_mutex);
796
797 usb_pcwd = usb_get_intfdata(interface);
798 usb_set_intfdata(interface, NULL);
799
800 mutex_lock(&usb_pcwd->mtx);
801
802 /* Stop the timer before we leave */
803 if (!nowayout)
804 usb_pcwd_stop(usb_pcwd);
805
806 /* We should now stop communicating with the USB PCWD device */
807 usb_pcwd->exists = 0;
808
809 /* Deregister */
810 misc_deregister(&usb_pcwd_miscdev);
811 misc_deregister(&usb_pcwd_temperature_miscdev);
812 unregister_reboot_notifier(&usb_pcwd_notifier);
813
814 mutex_unlock(&usb_pcwd->mtx);
815
816 /* Delete the USB PCWD device */
817 usb_pcwd_delete(usb_pcwd);
818
819 cards_found--;
820
821 mutex_unlock(&disconnect_mutex);
822
823 pr_info("USB PC Watchdog disconnected\n");
824}
825
826module_usb_driver(usb_pcwd_driver);