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 | |
50 | MODULE_AUTHOR(DRIVER_AUTHOR); |
51 | MODULE_DESCRIPTION(DRIVER_DESC); |
52 | MODULE_LICENSE("GPL" ); |
53 | |
54 | #define WATCHDOG_HEARTBEAT 0 /* default heartbeat = |
55 | delay-time from dip-switches */ |
56 | static int heartbeat = WATCHDOG_HEARTBEAT; |
57 | module_param(heartbeat, int, 0); |
58 | MODULE_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 | |
62 | static bool nowayout = WATCHDOG_NOWAYOUT; |
63 | module_param(nowayout, bool, 0); |
64 | MODULE_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 */ |
72 | static const struct usb_device_id usb_pcwd_table[] = { |
73 | { USB_DEVICE(USB_PCWD_VENDOR_ID, USB_PCWD_PRODUCT_ID) }, |
74 | { } /* Terminating entry */ |
75 | }; |
76 | MODULE_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 */ |
95 | static 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 */ |
107 | static int cards_found; |
108 | |
109 | /* some internal variables */ |
110 | static unsigned long is_active; |
111 | static char expect_release; |
112 | |
113 | /* Structure to hold all of our device specific stuff */ |
114 | struct 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 | }; |
146 | static struct usb_pcwd_private *usb_pcwd_device; |
147 | |
148 | /* prevent races between open() and disconnect() */ |
149 | static DEFINE_MUTEX(disconnect_mutex); |
150 | |
151 | /* local function prototypes */ |
152 | static int usb_pcwd_probe(struct usb_interface *interface, |
153 | const struct usb_device_id *id); |
154 | static void usb_pcwd_disconnect(struct usb_interface *interface); |
155 | |
156 | /* usb specific object needed to register this driver with the usb subsystem */ |
157 | static 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 | |
165 | static 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(v: &usb_pcwd->cmd_received, i: 1); |
199 | |
200 | resubmit: |
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 | |
207 | static 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(size: 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(v: &usb_pcwd->cmd_received, i: 0); |
234 | |
235 | if (usb_control_msg(dev: usb_pcwd->udev, usb_sndctrlpipe(usb_pcwd->udev, 0), |
236 | request: HID_REQ_SET_REPORT, HID_DT_REPORT, |
237 | value: 0x0200, index: usb_pcwd->interface_number, data: buf, size: 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(v: &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(objp: buf); |
260 | |
261 | return got_response; |
262 | } |
263 | |
264 | static 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: &msb, lsb: &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 | |
282 | static 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: &msb, lsb: &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 | |
300 | static 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, msb: &dummy, lsb: &dummy); |
306 | |
307 | return 0; |
308 | } |
309 | |
310 | static 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: &msb, lsb: &lsb); |
320 | |
321 | heartbeat = t; |
322 | return 0; |
323 | } |
324 | |
325 | static 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: &msb, lsb: &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 | |
342 | static 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: &msb, lsb: &lsb); |
351 | |
352 | *time_left = (msb << 8) + lsb; |
353 | |
354 | return 0; |
355 | } |
356 | |
357 | /* |
358 | * /dev/watchdog handling |
359 | */ |
360 | |
361 | static 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: usb_pcwd_device); |
386 | } |
387 | return len; |
388 | } |
389 | |
390 | static 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(to: argp, from: &ident, n: 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: usb_pcwd_device, temperature: &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: usb_pcwd_device); |
430 | retval = 0; |
431 | } |
432 | |
433 | if (new_options & WDIOS_ENABLECARD) { |
434 | usb_pcwd_start(usb_pcwd: usb_pcwd_device); |
435 | retval = 0; |
436 | } |
437 | |
438 | return retval; |
439 | } |
440 | |
441 | case WDIOC_KEEPALIVE: |
442 | usb_pcwd_keepalive(usb_pcwd: 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: usb_pcwd_device, t: new_heartbeat)) |
453 | return -EINVAL; |
454 | |
455 | usb_pcwd_keepalive(usb_pcwd: 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: usb_pcwd_device, time_left: &time_left)) |
467 | return -EFAULT; |
468 | |
469 | return put_user(time_left, p); |
470 | } |
471 | |
472 | default: |
473 | return -ENOTTY; |
474 | } |
475 | } |
476 | |
477 | static 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(nr: 0, addr: &is_active)) |
481 | return -EBUSY; |
482 | |
483 | /* Activate */ |
484 | usb_pcwd_start(usb_pcwd: usb_pcwd_device); |
485 | usb_pcwd_keepalive(usb_pcwd: usb_pcwd_device); |
486 | return stream_open(inode, filp: file); |
487 | } |
488 | |
489 | static 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: usb_pcwd_device); |
496 | } else { |
497 | pr_crit("Unexpected close, not stopping watchdog!\n" ); |
498 | usb_pcwd_keepalive(usb_pcwd: usb_pcwd_device); |
499 | } |
500 | expect_release = 0; |
501 | clear_bit(nr: 0, addr: &is_active); |
502 | return 0; |
503 | } |
504 | |
505 | /* |
506 | * /dev/temperature handling |
507 | */ |
508 | |
509 | static 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: usb_pcwd_device, temperature: &temperature)) |
515 | return -EFAULT; |
516 | |
517 | if (copy_to_user(to: data, from: &temperature, n: 1)) |
518 | return -EFAULT; |
519 | |
520 | return 1; |
521 | } |
522 | |
523 | static int usb_pcwd_temperature_open(struct inode *inode, struct file *file) |
524 | { |
525 | return stream_open(inode, filp: file); |
526 | } |
527 | |
528 | static int usb_pcwd_temperature_release(struct inode *inode, struct file *file) |
529 | { |
530 | return 0; |
531 | } |
532 | |
533 | /* |
534 | * Notify system |
535 | */ |
536 | |
537 | static 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: usb_pcwd_device); /* Turn the WDT off */ |
542 | |
543 | return NOTIFY_DONE; |
544 | } |
545 | |
546 | /* |
547 | * Kernel Interfaces |
548 | */ |
549 | |
550 | static 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 | |
560 | static struct miscdevice usb_pcwd_miscdev = { |
561 | .minor = WATCHDOG_MINOR, |
562 | .name = "watchdog" , |
563 | .fops = &usb_pcwd_fops, |
564 | }; |
565 | |
566 | static 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 | |
574 | static struct miscdevice usb_pcwd_temperature_miscdev = { |
575 | .minor = TEMP_MINOR, |
576 | .name = "temperature" , |
577 | .fops = &usb_pcwd_temperature_fops, |
578 | }; |
579 | |
580 | static struct notifier_block usb_pcwd_notifier = { |
581 | .notifier_call = usb_pcwd_notify_sys, |
582 | }; |
583 | |
584 | /** |
585 | * usb_pcwd_delete |
586 | */ |
587 | static inline void usb_pcwd_delete(struct usb_pcwd_private *usb_pcwd) |
588 | { |
589 | usb_free_urb(urb: usb_pcwd->intr_urb); |
590 | usb_free_coherent(dev: usb_pcwd->udev, size: usb_pcwd->intr_size, |
591 | addr: usb_pcwd->intr_buffer, dma: usb_pcwd->intr_dma); |
592 | kfree(objp: 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 | */ |
601 | static 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(epd: 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(size: 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(dev: udev, size: usb_pcwd->intr_size, |
661 | GFP_KERNEL, dma: &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(iso_packets: 0, GFP_KERNEL); |
669 | if (!usb_pcwd->intr_urb) |
670 | goto error; |
671 | |
672 | /* initialise the intr urb's */ |
673 | usb_fill_int_urb(urb: usb_pcwd->intr_urb, dev: udev, pipe, |
674 | transfer_buffer: usb_pcwd->intr_buffer, buffer_length: usb_pcwd->intr_size, |
675 | complete_fn: usb_pcwd_intr_done, context: usb_pcwd, interval: 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(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 | msb: &fw_rev_major, lsb: &fw_rev_minor); |
695 | if (got_fw_rev) |
696 | sprintf(buf: fw_ver_str, fmt: "%u.%02u" , fw_rev_major, fw_rev_minor); |
697 | else |
698 | sprintf(buf: fw_ver_str, fmt: "<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, msb: &dummy, |
704 | lsb: &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, t: 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(misc: &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(misc: &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(intf: interface, data: usb_pcwd); |
745 | |
746 | pr_info("initialized. heartbeat=%d sec (nowayout=%d)\n" , |
747 | heartbeat, nowayout); |
748 | |
749 | return 0; |
750 | |
751 | err_out_misc_deregister: |
752 | misc_deregister(misc: &usb_pcwd_temperature_miscdev); |
753 | err_out_unregister_reboot: |
754 | unregister_reboot_notifier(&usb_pcwd_notifier); |
755 | error: |
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 | */ |
771 | static 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(intf: interface); |
779 | usb_set_intfdata(intf: 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(misc: &usb_pcwd_miscdev); |
792 | misc_deregister(misc: &usb_pcwd_temperature_miscdev); |
793 | unregister_reboot_notifier(&usb_pcwd_notifier); |
794 | |
795 | mutex_unlock(lock: &usb_pcwd->mtx); |
796 | |
797 | /* Delete the USB PCWD device */ |
798 | usb_pcwd_delete(usb_pcwd); |
799 | |
800 | cards_found--; |
801 | |
802 | mutex_unlock(lock: &disconnect_mutex); |
803 | |
804 | pr_info("USB PC Watchdog disconnected\n" ); |
805 | } |
806 | |
807 | module_usb_driver(usb_pcwd_driver); |
808 | |