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