Commit | Line | Data |
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2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
485ae77d SA |
2 | /* |
3 | * SMsC 37B787 Watchdog Timer driver for Linux 2.6.x.x | |
4 | * | |
29fa0586 | 5 | * Based on acquirewdt.c by Alan Cox <alan@lxorguk.ukuu.org.uk> |
143a2e54 | 6 | * and some other existing drivers |
485ae77d | 7 | * |
485ae77d SA |
8 | * The authors do NOT admit liability nor provide warranty for |
9 | * any of this software. This material is provided "AS-IS" in | |
143a2e54 | 10 | * the hope that it may be useful for others. |
485ae77d SA |
11 | * |
12 | * (C) Copyright 2003-2006 Sven Anders <anders@anduras.de> | |
13 | * | |
14 | * History: | |
15 | * 2003 - Created version 1.0 for Linux 2.4.x. | |
16 | * 2006 - Ported to Linux 2.6, added nowayout and MAGICCLOSE | |
59846793 | 17 | * features. Released version 1.1 |
485ae77d SA |
18 | * |
19 | * Theory of operation: | |
20 | * | |
143a2e54 WVS |
21 | * A Watchdog Timer (WDT) is a hardware circuit that can |
22 | * reset the computer system in case of a software fault. | |
23 | * You probably knew that already. | |
485ae77d | 24 | * |
143a2e54 WVS |
25 | * Usually a userspace daemon will notify the kernel WDT driver |
26 | * via the /dev/watchdog special device file that userspace is | |
27 | * still alive, at regular intervals. When such a notification | |
28 | * occurs, the driver will usually tell the hardware watchdog | |
29 | * that everything is in order, and that the watchdog should wait | |
30 | * for yet another little while to reset the system. | |
31 | * If userspace fails (RAM error, kernel bug, whatever), the | |
32 | * notifications cease to occur, and the hardware watchdog will | |
33 | * reset the system (causing a reboot) after the timeout occurs. | |
485ae77d SA |
34 | * |
35 | * Create device with: | |
36 | * mknod /dev/watchdog c 10 130 | |
37 | * | |
38 | * For an example userspace keep-alive daemon, see: | |
395cf969 | 39 | * Documentation/watchdog/wdt.txt |
485ae77d SA |
40 | */ |
41 | ||
27c766aa JP |
42 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
43 | ||
485ae77d SA |
44 | #include <linux/module.h> |
45 | #include <linux/moduleparam.h> | |
46 | #include <linux/types.h> | |
47 | #include <linux/miscdevice.h> | |
48 | #include <linux/watchdog.h> | |
49 | #include <linux/delay.h> | |
50 | #include <linux/fs.h> | |
51 | #include <linux/ioport.h> | |
52 | #include <linux/notifier.h> | |
53 | #include <linux/reboot.h> | |
54 | #include <linux/init.h> | |
aa1fd4d7 | 55 | #include <linux/spinlock.h> |
59846793 AC |
56 | #include <linux/io.h> |
57 | #include <linux/uaccess.h> | |
485ae77d | 58 | |
485ae77d SA |
59 | |
60 | /* enable support for minutes as units? */ | |
61 | /* (does not always work correctly, so disabled by default!) */ | |
62 | #define SMSC_SUPPORT_MINUTES | |
63 | #undef SMSC_SUPPORT_MINUTES | |
64 | ||
65 | #define MAX_TIMEOUT 255 | |
66 | ||
67 | #define UNIT_SECOND 0 | |
68 | #define UNIT_MINUTE 1 | |
69 | ||
59846793 | 70 | #define VERSION "1.1" |
485ae77d | 71 | |
59846793 | 72 | #define IOPORT 0x3F0 |
485ae77d | 73 | #define IOPORT_SIZE 2 |
59846793 | 74 | #define IODEV_NO 8 |
485ae77d | 75 | |
59846793 AC |
76 | static int unit = UNIT_SECOND; /* timer's unit */ |
77 | static int timeout = 60; /* timeout value: default is 60 "units" */ | |
78 | static unsigned long timer_enabled; /* is the timer enabled? */ | |
485ae77d SA |
79 | |
80 | static char expect_close; /* is the close expected? */ | |
81 | ||
c7dfd0cc | 82 | static DEFINE_SPINLOCK(io_lock);/* to guard the watchdog from io races */ |
aa1fd4d7 | 83 | |
86a1e189 | 84 | static bool nowayout = WATCHDOG_NOWAYOUT; |
485ae77d SA |
85 | |
86 | /* -- Low level function ----------------------------------------*/ | |
87 | ||
88 | /* unlock the IO chip */ | |
89 | ||
90 | static inline void open_io_config(void) | |
91 | { | |
59846793 | 92 | outb(0x55, IOPORT); |
485ae77d | 93 | mdelay(1); |
59846793 | 94 | outb(0x55, IOPORT); |
485ae77d SA |
95 | } |
96 | ||
97 | /* lock the IO chip */ | |
98 | static inline void close_io_config(void) | |
99 | { | |
59846793 | 100 | outb(0xAA, IOPORT); |
485ae77d SA |
101 | } |
102 | ||
103 | /* select the IO device */ | |
104 | static inline void select_io_device(unsigned char devno) | |
105 | { | |
59846793 AC |
106 | outb(0x07, IOPORT); |
107 | outb(devno, IOPORT+1); | |
485ae77d SA |
108 | } |
109 | ||
110 | /* write to the control register */ | |
111 | static inline void write_io_cr(unsigned char reg, unsigned char data) | |
112 | { | |
59846793 AC |
113 | outb(reg, IOPORT); |
114 | outb(data, IOPORT+1); | |
485ae77d SA |
115 | } |
116 | ||
117 | /* read from the control register */ | |
118 | static inline char read_io_cr(unsigned char reg) | |
119 | { | |
59846793 AC |
120 | outb(reg, IOPORT); |
121 | return inb(IOPORT+1); | |
485ae77d SA |
122 | } |
123 | ||
124 | /* -- Medium level functions ------------------------------------*/ | |
125 | ||
126 | static inline void gpio_bit12(unsigned char reg) | |
127 | { | |
59846793 AC |
128 | /* -- General Purpose I/O Bit 1.2 -- |
129 | * Bit 0, In/Out: 0 = Output, 1 = Input | |
130 | * Bit 1, Polarity: 0 = No Invert, 1 = Invert | |
131 | * Bit 2, Group Enable Intr.: 0 = Disable, 1 = Enable | |
132 | * Bit 3/4, Function select: 00 = GPI/O, 01 = WDT, 10 = P17, | |
133 | * 11 = Either Edge Triggered Intr. 2 | |
134 | * Bit 5/6 (Reserved) | |
135 | * Bit 7, Output Type: 0 = Push Pull Bit, 1 = Open Drain | |
136 | */ | |
137 | write_io_cr(0xE2, reg); | |
485ae77d SA |
138 | } |
139 | ||
140 | static inline void gpio_bit13(unsigned char reg) | |
141 | { | |
59846793 AC |
142 | /* -- General Purpose I/O Bit 1.3 -- |
143 | * Bit 0, In/Out: 0 = Output, 1 = Input | |
144 | * Bit 1, Polarity: 0 = No Invert, 1 = Invert | |
145 | * Bit 2, Group Enable Intr.: 0 = Disable, 1 = Enable | |
146 | * Bit 3, Function select: 0 = GPI/O, 1 = LED | |
147 | * Bit 4-6 (Reserved) | |
148 | * Bit 7, Output Type: 0 = Push Pull Bit, 1 = Open Drain | |
149 | */ | |
150 | write_io_cr(0xE3, reg); | |
485ae77d SA |
151 | } |
152 | ||
153 | static inline void wdt_timer_units(unsigned char new_units) | |
154 | { | |
59846793 AC |
155 | /* -- Watchdog timer units -- |
156 | * Bit 0-6 (Reserved) | |
157 | * Bit 7, WDT Time-out Value Units Select | |
158 | * (0 = Minutes, 1 = Seconds) | |
159 | */ | |
160 | write_io_cr(0xF1, new_units); | |
485ae77d SA |
161 | } |
162 | ||
163 | static inline void wdt_timeout_value(unsigned char new_timeout) | |
164 | { | |
59846793 AC |
165 | /* -- Watchdog Timer Time-out Value -- |
166 | * Bit 0-7 Binary coded units (0=Disabled, 1..255) | |
167 | */ | |
168 | write_io_cr(0xF2, new_timeout); | |
485ae77d SA |
169 | } |
170 | ||
171 | static inline void wdt_timer_conf(unsigned char conf) | |
172 | { | |
59846793 AC |
173 | /* -- Watchdog timer configuration -- |
174 | * Bit 0 Joystick enable: 0* = No Reset, 1 = Reset WDT upon | |
175 | * Gameport I/O | |
176 | * Bit 1 Keyboard enable: 0* = No Reset, 1 = Reset WDT upon KBD Intr. | |
177 | * Bit 2 Mouse enable: 0* = No Reset, 1 = Reset WDT upon Mouse Intr | |
178 | * Bit 3 Reset the timer | |
179 | * (Wrong in SMsC documentation? Given as: PowerLED Timout | |
180 | * Enabled) | |
181 | * Bit 4-7 WDT Interrupt Mapping: (0000* = Disabled, | |
182 | * 0001=IRQ1, 0010=(Invalid), 0011=IRQ3 to 1111=IRQ15) | |
183 | */ | |
184 | write_io_cr(0xF3, conf); | |
485ae77d SA |
185 | } |
186 | ||
187 | static inline void wdt_timer_ctrl(unsigned char reg) | |
188 | { | |
59846793 | 189 | /* -- Watchdog timer control -- |
25985edc | 190 | * Bit 0 Status Bit: 0 = Timer counting, 1 = Timeout occurred |
59846793 AC |
191 | * Bit 1 Power LED Toggle: 0 = Disable Toggle, 1 = Toggle at 1 Hz |
192 | * Bit 2 Force Timeout: 1 = Forces WD timeout event (self-cleaning) | |
193 | * Bit 3 P20 Force Timeout enabled: | |
194 | * 0 = P20 activity does not generate the WD timeout event | |
195 | * 1 = P20 Allows rising edge of P20, from the keyboard | |
196 | * controller, to force the WD timeout event. | |
197 | * Bit 4 (Reserved) | |
198 | * -- Soft power management -- | |
199 | * Bit 5 Stop Counter: 1 = Stop software power down counter | |
200 | * set via register 0xB8, (self-cleaning) | |
201 | * (Upon read: 0 = Counter running, 1 = Counter stopped) | |
202 | * Bit 6 Restart Counter: 1 = Restart software power down counter | |
203 | * set via register 0xB8, (self-cleaning) | |
204 | * Bit 7 SPOFF: 1 = Force software power down (self-cleaning) | |
205 | */ | |
206 | write_io_cr(0xF4, reg); | |
485ae77d SA |
207 | } |
208 | ||
209 | /* -- Higher level functions ------------------------------------*/ | |
210 | ||
211 | /* initialize watchdog */ | |
212 | ||
213 | static void wb_smsc_wdt_initialize(void) | |
214 | { | |
59846793 | 215 | unsigned char old; |
485ae77d | 216 | |
aa1fd4d7 | 217 | spin_lock(&io_lock); |
59846793 AC |
218 | open_io_config(); |
219 | select_io_device(IODEV_NO); | |
485ae77d | 220 | |
59846793 AC |
221 | /* enable the watchdog */ |
222 | gpio_bit13(0x08); /* Select pin 80 = LED not GPIO */ | |
223 | gpio_bit12(0x0A); /* Set pin 79 = WDT not | |
224 | GPIO/Output/Polarity=Invert */ | |
225 | /* disable the timeout */ | |
226 | wdt_timeout_value(0); | |
485ae77d | 227 | |
59846793 AC |
228 | /* reset control register */ |
229 | wdt_timer_ctrl(0x00); | |
485ae77d | 230 | |
59846793 | 231 | /* reset configuration register */ |
485ae77d SA |
232 | wdt_timer_conf(0x00); |
233 | ||
59846793 AC |
234 | /* read old (timer units) register */ |
235 | old = read_io_cr(0xF1) & 0x7F; | |
236 | if (unit == UNIT_SECOND) | |
237 | old |= 0x80; /* set to seconds */ | |
485ae77d | 238 | |
59846793 AC |
239 | /* set the watchdog timer units */ |
240 | wdt_timer_units(old); | |
485ae77d | 241 | |
59846793 | 242 | close_io_config(); |
aa1fd4d7 | 243 | spin_unlock(&io_lock); |
485ae77d SA |
244 | } |
245 | ||
246 | /* shutdown the watchdog */ | |
247 | ||
248 | static void wb_smsc_wdt_shutdown(void) | |
249 | { | |
aa1fd4d7 | 250 | spin_lock(&io_lock); |
59846793 AC |
251 | open_io_config(); |
252 | select_io_device(IODEV_NO); | |
485ae77d | 253 | |
59846793 AC |
254 | /* disable the watchdog */ |
255 | gpio_bit13(0x09); | |
256 | gpio_bit12(0x09); | |
485ae77d | 257 | |
59846793 | 258 | /* reset watchdog config register */ |
485ae77d SA |
259 | wdt_timer_conf(0x00); |
260 | ||
59846793 AC |
261 | /* reset watchdog control register */ |
262 | wdt_timer_ctrl(0x00); | |
485ae77d | 263 | |
59846793 AC |
264 | /* disable timeout */ |
265 | wdt_timeout_value(0x00); | |
485ae77d | 266 | |
59846793 | 267 | close_io_config(); |
aa1fd4d7 | 268 | spin_unlock(&io_lock); |
485ae77d SA |
269 | } |
270 | ||
271 | /* set timeout => enable watchdog */ | |
272 | ||
273 | static void wb_smsc_wdt_set_timeout(unsigned char new_timeout) | |
274 | { | |
aa1fd4d7 | 275 | spin_lock(&io_lock); |
59846793 AC |
276 | open_io_config(); |
277 | select_io_device(IODEV_NO); | |
485ae77d | 278 | |
59846793 AC |
279 | /* set Power LED to blink, if we enable the timeout */ |
280 | wdt_timer_ctrl((new_timeout == 0) ? 0x00 : 0x02); | |
485ae77d | 281 | |
59846793 AC |
282 | /* set timeout value */ |
283 | wdt_timeout_value(new_timeout); | |
485ae77d | 284 | |
59846793 | 285 | close_io_config(); |
aa1fd4d7 | 286 | spin_unlock(&io_lock); |
485ae77d SA |
287 | } |
288 | ||
289 | /* get timeout */ | |
290 | ||
291 | static unsigned char wb_smsc_wdt_get_timeout(void) | |
292 | { | |
59846793 | 293 | unsigned char set_timeout; |
485ae77d | 294 | |
aa1fd4d7 | 295 | spin_lock(&io_lock); |
59846793 AC |
296 | open_io_config(); |
297 | select_io_device(IODEV_NO); | |
298 | set_timeout = read_io_cr(0xF2); | |
299 | close_io_config(); | |
aa1fd4d7 | 300 | spin_unlock(&io_lock); |
485ae77d | 301 | |
59846793 | 302 | return set_timeout; |
485ae77d SA |
303 | } |
304 | ||
305 | /* disable watchdog */ | |
306 | ||
307 | static void wb_smsc_wdt_disable(void) | |
308 | { | |
59846793 AC |
309 | /* set the timeout to 0 to disable the watchdog */ |
310 | wb_smsc_wdt_set_timeout(0); | |
485ae77d SA |
311 | } |
312 | ||
313 | /* enable watchdog by setting the current timeout */ | |
314 | ||
315 | static void wb_smsc_wdt_enable(void) | |
316 | { | |
59846793 AC |
317 | /* set the current timeout... */ |
318 | wb_smsc_wdt_set_timeout(timeout); | |
485ae77d SA |
319 | } |
320 | ||
321 | /* reset the timer */ | |
322 | ||
323 | static void wb_smsc_wdt_reset_timer(void) | |
324 | { | |
aa1fd4d7 | 325 | spin_lock(&io_lock); |
59846793 AC |
326 | open_io_config(); |
327 | select_io_device(IODEV_NO); | |
485ae77d | 328 | |
59846793 | 329 | /* reset the timer */ |
485ae77d SA |
330 | wdt_timeout_value(timeout); |
331 | wdt_timer_conf(0x08); | |
332 | ||
59846793 | 333 | close_io_config(); |
aa1fd4d7 | 334 | spin_unlock(&io_lock); |
485ae77d SA |
335 | } |
336 | ||
337 | /* return, if the watchdog is enabled (timeout is set...) */ | |
338 | ||
339 | static int wb_smsc_wdt_status(void) | |
340 | { | |
341 | return (wb_smsc_wdt_get_timeout() == 0) ? 0 : WDIOF_KEEPALIVEPING; | |
342 | } | |
343 | ||
344 | ||
345 | /* -- File operations -------------------------------------------*/ | |
346 | ||
347 | /* open => enable watchdog and set initial timeout */ | |
348 | ||
349 | static int wb_smsc_wdt_open(struct inode *inode, struct file *file) | |
350 | { | |
351 | /* /dev/watchdog can only be opened once */ | |
352 | ||
aa1fd4d7 | 353 | if (test_and_set_bit(0, &timer_enabled)) |
485ae77d SA |
354 | return -EBUSY; |
355 | ||
356 | if (nowayout) | |
357 | __module_get(THIS_MODULE); | |
358 | ||
359 | /* Reload and activate timer */ | |
485ae77d SA |
360 | wb_smsc_wdt_enable(); |
361 | ||
27c766aa | 362 | pr_info("Watchdog enabled. Timeout set to %d %s\n", |
59846793 | 363 | timeout, (unit == UNIT_SECOND) ? "second(s)" : "minute(s)"); |
485ae77d | 364 | |
c5bf68fe | 365 | return stream_open(inode, file); |
485ae77d SA |
366 | } |
367 | ||
368 | /* close => shut off the timer */ | |
369 | ||
370 | static int wb_smsc_wdt_release(struct inode *inode, struct file *file) | |
371 | { | |
372 | /* Shut off the timer. */ | |
373 | ||
374 | if (expect_close == 42) { | |
59846793 | 375 | wb_smsc_wdt_disable(); |
27c766aa | 376 | pr_info("Watchdog disabled, sleeping again...\n"); |
485ae77d | 377 | } else { |
27c766aa | 378 | pr_crit("Unexpected close, not stopping watchdog!\n"); |
485ae77d SA |
379 | wb_smsc_wdt_reset_timer(); |
380 | } | |
381 | ||
aa1fd4d7 | 382 | clear_bit(0, &timer_enabled); |
485ae77d SA |
383 | expect_close = 0; |
384 | return 0; | |
385 | } | |
386 | ||
387 | /* write => update the timer to keep the machine alive */ | |
388 | ||
389 | static ssize_t wb_smsc_wdt_write(struct file *file, const char __user *data, | |
390 | size_t len, loff_t *ppos) | |
391 | { | |
392 | /* See if we got the magic character 'V' and reload the timer */ | |
393 | if (len) { | |
394 | if (!nowayout) { | |
395 | size_t i; | |
396 | ||
397 | /* reset expect flag */ | |
398 | expect_close = 0; | |
399 | ||
59846793 AC |
400 | /* scan to see whether or not we got the |
401 | magic character */ | |
485ae77d SA |
402 | for (i = 0; i != len; i++) { |
403 | char c; | |
7944d3a5 | 404 | if (get_user(c, data + i)) |
485ae77d SA |
405 | return -EFAULT; |
406 | if (c == 'V') | |
407 | expect_close = 42; | |
408 | } | |
409 | } | |
410 | ||
411 | /* someone wrote to us, we should reload the timer */ | |
412 | wb_smsc_wdt_reset_timer(); | |
413 | } | |
414 | return len; | |
415 | } | |
416 | ||
417 | /* ioctl => control interface */ | |
418 | ||
59846793 AC |
419 | static long wb_smsc_wdt_ioctl(struct file *file, |
420 | unsigned int cmd, unsigned long arg) | |
485ae77d SA |
421 | { |
422 | int new_timeout; | |
423 | ||
424 | union { | |
425 | struct watchdog_info __user *ident; | |
426 | int __user *i; | |
427 | } uarg; | |
428 | ||
59846793 | 429 | static const struct watchdog_info ident = { |
5f3b2756 | 430 | .options = WDIOF_KEEPALIVEPING | |
59846793 | 431 | WDIOF_SETTIMEOUT | |
485ae77d SA |
432 | WDIOF_MAGICCLOSE, |
433 | .firmware_version = 0, | |
5f3b2756 | 434 | .identity = "SMsC 37B787 Watchdog", |
485ae77d SA |
435 | }; |
436 | ||
437 | uarg.i = (int __user *)arg; | |
438 | ||
439 | switch (cmd) { | |
59846793 AC |
440 | case WDIOC_GETSUPPORT: |
441 | return copy_to_user(uarg.ident, &ident, sizeof(ident)) | |
442 | ? -EFAULT : 0; | |
443 | case WDIOC_GETSTATUS: | |
444 | return put_user(wb_smsc_wdt_status(), uarg.i); | |
445 | case WDIOC_GETBOOTSTATUS: | |
446 | return put_user(0, uarg.i); | |
0c06090c WVS |
447 | case WDIOC_SETOPTIONS: |
448 | { | |
449 | int options, retval = -EINVAL; | |
450 | ||
451 | if (get_user(options, uarg.i)) | |
452 | return -EFAULT; | |
453 | ||
454 | if (options & WDIOS_DISABLECARD) { | |
455 | wb_smsc_wdt_disable(); | |
456 | retval = 0; | |
457 | } | |
458 | if (options & WDIOS_ENABLECARD) { | |
459 | wb_smsc_wdt_enable(); | |
460 | retval = 0; | |
461 | } | |
462 | return retval; | |
463 | } | |
59846793 AC |
464 | case WDIOC_KEEPALIVE: |
465 | wb_smsc_wdt_reset_timer(); | |
466 | return 0; | |
467 | case WDIOC_SETTIMEOUT: | |
468 | if (get_user(new_timeout, uarg.i)) | |
469 | return -EFAULT; | |
470 | /* the API states this is given in secs */ | |
471 | if (unit == UNIT_MINUTE) | |
472 | new_timeout /= 60; | |
473 | if (new_timeout < 0 || new_timeout > MAX_TIMEOUT) | |
474 | return -EINVAL; | |
475 | timeout = new_timeout; | |
476 | wb_smsc_wdt_set_timeout(timeout); | |
4a1b1161 | 477 | /* fall through - and return the new timeout... */ |
59846793 AC |
478 | case WDIOC_GETTIMEOUT: |
479 | new_timeout = timeout; | |
480 | if (unit == UNIT_MINUTE) | |
143a2e54 | 481 | new_timeout *= 60; |
59846793 | 482 | return put_user(new_timeout, uarg.i); |
59846793 AC |
483 | default: |
484 | return -ENOTTY; | |
485ae77d SA |
485 | } |
486 | } | |
487 | ||
488 | /* -- Notifier funtions -----------------------------------------*/ | |
489 | ||
59846793 AC |
490 | static int wb_smsc_wdt_notify_sys(struct notifier_block *this, |
491 | unsigned long code, void *unused) | |
485ae77d | 492 | { |
59846793 AC |
493 | if (code == SYS_DOWN || code == SYS_HALT) { |
494 | /* set timeout to 0, to avoid possible race-condition */ | |
495 | timeout = 0; | |
485ae77d SA |
496 | wb_smsc_wdt_disable(); |
497 | } | |
498 | return NOTIFY_DONE; | |
499 | } | |
500 | ||
501 | /* -- Module's structures ---------------------------------------*/ | |
502 | ||
59846793 AC |
503 | static const struct file_operations wb_smsc_wdt_fops = { |
504 | .owner = THIS_MODULE, | |
485ae77d SA |
505 | .llseek = no_llseek, |
506 | .write = wb_smsc_wdt_write, | |
59846793 | 507 | .unlocked_ioctl = wb_smsc_wdt_ioctl, |
485ae77d | 508 | .open = wb_smsc_wdt_open, |
aa1fd4d7 | 509 | .release = wb_smsc_wdt_release, |
485ae77d SA |
510 | }; |
511 | ||
59846793 | 512 | static struct notifier_block wb_smsc_wdt_notifier = { |
aa1fd4d7 | 513 | .notifier_call = wb_smsc_wdt_notify_sys, |
485ae77d SA |
514 | }; |
515 | ||
59846793 | 516 | static struct miscdevice wb_smsc_wdt_miscdev = { |
485ae77d SA |
517 | .minor = WATCHDOG_MINOR, |
518 | .name = "watchdog", | |
519 | .fops = &wb_smsc_wdt_fops, | |
520 | }; | |
521 | ||
522 | /* -- Module init functions -------------------------------------*/ | |
523 | ||
524 | /* module's "constructor" */ | |
525 | ||
526 | static int __init wb_smsc_wdt_init(void) | |
527 | { | |
528 | int ret; | |
529 | ||
27c766aa JP |
530 | pr_info("SMsC 37B787 watchdog component driver " |
531 | VERSION " initialising...\n"); | |
485ae77d SA |
532 | |
533 | if (!request_region(IOPORT, IOPORT_SIZE, "SMsC 37B787 watchdog")) { | |
27c766aa | 534 | pr_err("Unable to register IO port %#x\n", IOPORT); |
485ae77d SA |
535 | ret = -EBUSY; |
536 | goto out_pnp; | |
537 | } | |
538 | ||
59846793 AC |
539 | /* set new maximum, if it's too big */ |
540 | if (timeout > MAX_TIMEOUT) | |
541 | timeout = MAX_TIMEOUT; | |
aa1fd4d7 | 542 | |
59846793 AC |
543 | /* init the watchdog timer */ |
544 | wb_smsc_wdt_initialize(); | |
aa1fd4d7 | 545 | |
485ae77d SA |
546 | ret = register_reboot_notifier(&wb_smsc_wdt_notifier); |
547 | if (ret) { | |
27c766aa | 548 | pr_err("Unable to register reboot notifier err = %d\n", ret); |
485ae77d SA |
549 | goto out_io; |
550 | } | |
551 | ||
552 | ret = misc_register(&wb_smsc_wdt_miscdev); | |
553 | if (ret) { | |
27c766aa JP |
554 | pr_err("Unable to register miscdev on minor %d\n", |
555 | WATCHDOG_MINOR); | |
485ae77d SA |
556 | goto out_rbt; |
557 | } | |
558 | ||
59846793 | 559 | /* output info */ |
27c766aa | 560 | pr_info("Timeout set to %d %s\n", |
59846793 | 561 | timeout, (unit == UNIT_SECOND) ? "second(s)" : "minute(s)"); |
27c766aa JP |
562 | pr_info("Watchdog initialized and sleeping (nowayout=%d)...\n", |
563 | nowayout); | |
485ae77d SA |
564 | out_clean: |
565 | return ret; | |
566 | ||
567 | out_rbt: | |
568 | unregister_reboot_notifier(&wb_smsc_wdt_notifier); | |
569 | ||
570 | out_io: | |
571 | release_region(IOPORT, IOPORT_SIZE); | |
572 | ||
573 | out_pnp: | |
574 | goto out_clean; | |
8386c8cf | 575 | } |
485ae77d SA |
576 | |
577 | /* module's "destructor" */ | |
578 | ||
579 | static void __exit wb_smsc_wdt_exit(void) | |
580 | { | |
581 | /* Stop the timer before we leave */ | |
59846793 | 582 | if (!nowayout) { |
485ae77d | 583 | wb_smsc_wdt_shutdown(); |
27c766aa | 584 | pr_info("Watchdog disabled\n"); |
485ae77d SA |
585 | } |
586 | ||
587 | misc_deregister(&wb_smsc_wdt_miscdev); | |
588 | unregister_reboot_notifier(&wb_smsc_wdt_notifier); | |
589 | release_region(IOPORT, IOPORT_SIZE); | |
590 | ||
27c766aa | 591 | pr_info("SMsC 37B787 watchdog component driver removed\n"); |
485ae77d SA |
592 | } |
593 | ||
594 | module_init(wb_smsc_wdt_init); | |
595 | module_exit(wb_smsc_wdt_exit); | |
596 | ||
597 | MODULE_AUTHOR("Sven Anders <anders@anduras.de>"); | |
59846793 AC |
598 | MODULE_DESCRIPTION("Driver for SMsC 37B787 watchdog component (Version " |
599 | VERSION ")"); | |
485ae77d SA |
600 | MODULE_LICENSE("GPL"); |
601 | ||
485ae77d SA |
602 | #ifdef SMSC_SUPPORT_MINUTES |
603 | module_param(unit, int, 0); | |
59846793 AC |
604 | MODULE_PARM_DESC(unit, |
605 | "set unit to use, 0=seconds or 1=minutes, default is 0"); | |
485ae77d SA |
606 | #endif |
607 | ||
aa1fd4d7 | 608 | module_param(timeout, int, 0); |
485ae77d SA |
609 | MODULE_PARM_DESC(timeout, "range is 1-255 units, default is 60"); |
610 | ||
86a1e189 | 611 | module_param(nowayout, bool, 0); |
59846793 AC |
612 | MODULE_PARM_DESC(nowayout, |
613 | "Watchdog cannot be stopped once started (default=" | |
614 | __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); |