Commit | Line | Data |
---|---|---|
38ff6fd2 JBD |
1 | /* |
2 | * IT8712F "Smart Guardian" Watchdog support | |
3 | * | |
4 | * Copyright (c) 2006-2007 Jorge Boncompte - DTI2 <jorge@dti2.net> | |
5 | * | |
6 | * Based on info and code taken from: | |
7 | * | |
8 | * drivers/char/watchdog/scx200_wdt.c | |
9 | * drivers/hwmon/it87.c | |
5e699608 AP |
10 | * IT8712F EC-LPC I/O Preliminary Specification 0.8.2 |
11 | * IT8712F EC-LPC I/O Preliminary Specification 0.9.3 | |
38ff6fd2 JBD |
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 as | |
15 | * published by the Free Software Foundation; either version 2 of the | |
16 | * License, or (at your option) any later version. | |
17 | * | |
18 | * The author(s) of this software shall not be held liable for damages | |
19 | * of any nature resulting due to the use of this software. This | |
20 | * software is provided AS-IS with no warranties. | |
21 | */ | |
22 | ||
27c766aa JP |
23 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
24 | ||
38ff6fd2 JBD |
25 | #include <linux/module.h> |
26 | #include <linux/moduleparam.h> | |
27 | #include <linux/init.h> | |
28 | #include <linux/miscdevice.h> | |
29 | #include <linux/watchdog.h> | |
30 | #include <linux/notifier.h> | |
31 | #include <linux/reboot.h> | |
32 | #include <linux/fs.h> | |
38ff6fd2 | 33 | #include <linux/spinlock.h> |
d6547378 AC |
34 | #include <linux/uaccess.h> |
35 | #include <linux/io.h> | |
22602868 | 36 | #include <linux/ioport.h> |
38ff6fd2 | 37 | |
27c766aa | 38 | #define DEBUG |
38ff6fd2 JBD |
39 | #define NAME "it8712f_wdt" |
40 | ||
41 | MODULE_AUTHOR("Jorge Boncompte - DTI2 <jorge@dti2.net>"); | |
42 | MODULE_DESCRIPTION("IT8712F Watchdog Driver"); | |
43 | MODULE_LICENSE("GPL"); | |
38ff6fd2 | 44 | |
5e699608 | 45 | static int max_units = 255; |
38ff6fd2 JBD |
46 | static int margin = 60; /* in seconds */ |
47 | module_param(margin, int, 0); | |
48 | MODULE_PARM_DESC(margin, "Watchdog margin in seconds"); | |
49 | ||
86a1e189 WVS |
50 | static bool nowayout = WATCHDOG_NOWAYOUT; |
51 | module_param(nowayout, bool, 0); | |
38ff6fd2 JBD |
52 | MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close"); |
53 | ||
d6547378 | 54 | static unsigned long wdt_open; |
38ff6fd2 | 55 | static unsigned expect_close; |
5e699608 | 56 | static unsigned char revision; |
38ff6fd2 JBD |
57 | |
58 | /* Dog Food address - We use the game port address */ | |
59 | static unsigned short address; | |
60 | ||
61 | #define REG 0x2e /* The register to read/write */ | |
62 | #define VAL 0x2f /* The value to read/write */ | |
63 | ||
64 | #define LDN 0x07 /* Register: Logical device select */ | |
65 | #define DEVID 0x20 /* Register: Device ID */ | |
66 | #define DEVREV 0x22 /* Register: Device Revision */ | |
67 | #define ACT_REG 0x30 /* LDN Register: Activation */ | |
68 | #define BASE_REG 0x60 /* LDN Register: Base address */ | |
69 | ||
70 | #define IT8712F_DEVID 0x8712 | |
71 | ||
72 | #define LDN_GPIO 0x07 /* GPIO and Watch Dog Timer */ | |
5f3b2756 | 73 | #define LDN_GAME 0x09 /* Game Port */ |
38ff6fd2 JBD |
74 | |
75 | #define WDT_CONTROL 0x71 /* WDT Register: Control */ | |
76 | #define WDT_CONFIG 0x72 /* WDT Register: Configuration */ | |
77 | #define WDT_TIMEOUT 0x73 /* WDT Register: Timeout Value */ | |
78 | ||
f0fc1074 TJL |
79 | #define WDT_RESET_GAME 0x10 /* Reset timer on read or write to game port */ |
80 | #define WDT_RESET_KBD 0x20 /* Reset timer on keyboard interrupt */ | |
81 | #define WDT_RESET_MOUSE 0x40 /* Reset timer on mouse interrupt */ | |
82 | #define WDT_RESET_CIR 0x80 /* Reset timer on consumer IR interrupt */ | |
38ff6fd2 JBD |
83 | |
84 | #define WDT_UNIT_SEC 0x80 /* If 0 in MINUTES */ | |
85 | ||
f0fc1074 TJL |
86 | #define WDT_OUT_PWROK 0x10 /* Pulse PWROK on timeout */ |
87 | #define WDT_OUT_KRST 0x40 /* Pulse reset on timeout */ | |
38ff6fd2 | 88 | |
a422088d TJL |
89 | static int wdt_control_reg = WDT_RESET_GAME; |
90 | module_param(wdt_control_reg, int, 0); | |
91 | MODULE_PARM_DESC(wdt_control_reg, "Value to write to watchdog control " | |
92 | "register. The default WDT_RESET_GAME resets the timer on " | |
93 | "game port reads that this driver generates. You can also " | |
94 | "use KBD, MOUSE or CIR if you have some external way to " | |
95 | "generate those interrupts."); | |
96 | ||
d6547378 | 97 | static int superio_inb(int reg) |
38ff6fd2 JBD |
98 | { |
99 | outb(reg, REG); | |
100 | return inb(VAL); | |
101 | } | |
102 | ||
d6547378 | 103 | static void superio_outb(int val, int reg) |
38ff6fd2 JBD |
104 | { |
105 | outb(reg, REG); | |
106 | outb(val, VAL); | |
107 | } | |
108 | ||
d6547378 | 109 | static int superio_inw(int reg) |
38ff6fd2 JBD |
110 | { |
111 | int val; | |
112 | outb(reg++, REG); | |
113 | val = inb(VAL) << 8; | |
114 | outb(reg, REG); | |
115 | val |= inb(VAL); | |
116 | return val; | |
117 | } | |
118 | ||
d6547378 | 119 | static inline void superio_select(int ldn) |
38ff6fd2 JBD |
120 | { |
121 | outb(LDN, REG); | |
122 | outb(ldn, VAL); | |
123 | } | |
124 | ||
a134b825 | 125 | static inline int superio_enter(void) |
38ff6fd2 | 126 | { |
a134b825 NG |
127 | /* |
128 | * Try to reserve REG and REG + 1 for exclusive access. | |
129 | */ | |
130 | if (!request_muxed_region(REG, 2, NAME)) | |
131 | return -EBUSY; | |
132 | ||
38ff6fd2 JBD |
133 | outb(0x87, REG); |
134 | outb(0x01, REG); | |
135 | outb(0x55, REG); | |
136 | outb(0x55, REG); | |
a134b825 | 137 | return 0; |
38ff6fd2 JBD |
138 | } |
139 | ||
d6547378 | 140 | static inline void superio_exit(void) |
38ff6fd2 JBD |
141 | { |
142 | outb(0x02, REG); | |
143 | outb(0x02, VAL); | |
a134b825 | 144 | release_region(REG, 2); |
38ff6fd2 JBD |
145 | } |
146 | ||
d6547378 | 147 | static inline void it8712f_wdt_ping(void) |
38ff6fd2 | 148 | { |
a422088d TJL |
149 | if (wdt_control_reg & WDT_RESET_GAME) |
150 | inb(address); | |
38ff6fd2 JBD |
151 | } |
152 | ||
d6547378 | 153 | static void it8712f_wdt_update_margin(void) |
38ff6fd2 JBD |
154 | { |
155 | int config = WDT_OUT_KRST | WDT_OUT_PWROK; | |
5e699608 AP |
156 | int units = margin; |
157 | ||
158 | /* Switch to minutes precision if the configured margin | |
159 | * value does not fit within the register width. | |
160 | */ | |
161 | if (units <= max_units) { | |
162 | config |= WDT_UNIT_SEC; /* else UNIT is MINUTES */ | |
27c766aa | 163 | pr_info("timer margin %d seconds\n", units); |
5e699608 AP |
164 | } else { |
165 | units /= 60; | |
27c766aa | 166 | pr_info("timer margin %d minutes\n", units); |
5e699608 | 167 | } |
38ff6fd2 JBD |
168 | superio_outb(config, WDT_CONFIG); |
169 | ||
5e699608 | 170 | if (revision >= 0x08) |
0e45adb8 OS |
171 | superio_outb(units >> 8, WDT_TIMEOUT + 1); |
172 | superio_outb(units, WDT_TIMEOUT); | |
5e699608 AP |
173 | } |
174 | ||
d6547378 | 175 | static int it8712f_wdt_get_status(void) |
5e699608 AP |
176 | { |
177 | if (superio_inb(WDT_CONTROL) & 0x01) | |
178 | return WDIOF_CARDRESET; | |
179 | else | |
180 | return 0; | |
38ff6fd2 JBD |
181 | } |
182 | ||
a134b825 | 183 | static int it8712f_wdt_enable(void) |
38ff6fd2 | 184 | { |
a134b825 NG |
185 | int ret = superio_enter(); |
186 | if (ret) | |
187 | return ret; | |
188 | ||
27c766aa | 189 | pr_debug("enabling watchdog timer\n"); |
38ff6fd2 JBD |
190 | superio_select(LDN_GPIO); |
191 | ||
a422088d | 192 | superio_outb(wdt_control_reg, WDT_CONTROL); |
38ff6fd2 JBD |
193 | |
194 | it8712f_wdt_update_margin(); | |
195 | ||
196 | superio_exit(); | |
197 | ||
198 | it8712f_wdt_ping(); | |
a134b825 NG |
199 | |
200 | return 0; | |
38ff6fd2 JBD |
201 | } |
202 | ||
a134b825 | 203 | static int it8712f_wdt_disable(void) |
38ff6fd2 | 204 | { |
a134b825 NG |
205 | int ret = superio_enter(); |
206 | if (ret) | |
207 | return ret; | |
38ff6fd2 | 208 | |
27c766aa | 209 | pr_debug("disabling watchdog timer\n"); |
38ff6fd2 JBD |
210 | superio_select(LDN_GPIO); |
211 | ||
212 | superio_outb(0, WDT_CONFIG); | |
213 | superio_outb(0, WDT_CONTROL); | |
cc1020f1 AP |
214 | if (revision >= 0x08) |
215 | superio_outb(0, WDT_TIMEOUT + 1); | |
38ff6fd2 JBD |
216 | superio_outb(0, WDT_TIMEOUT); |
217 | ||
218 | superio_exit(); | |
a134b825 | 219 | return 0; |
38ff6fd2 JBD |
220 | } |
221 | ||
d6547378 | 222 | static int it8712f_wdt_notify(struct notifier_block *this, |
38ff6fd2 JBD |
223 | unsigned long code, void *unused) |
224 | { | |
225 | if (code == SYS_HALT || code == SYS_POWER_OFF) | |
226 | if (!nowayout) | |
227 | it8712f_wdt_disable(); | |
228 | ||
229 | return NOTIFY_DONE; | |
230 | } | |
231 | ||
232 | static struct notifier_block it8712f_wdt_notifier = { | |
233 | .notifier_call = it8712f_wdt_notify, | |
234 | }; | |
235 | ||
d6547378 AC |
236 | static ssize_t it8712f_wdt_write(struct file *file, const char __user *data, |
237 | size_t len, loff_t *ppos) | |
38ff6fd2 JBD |
238 | { |
239 | /* check for a magic close character */ | |
240 | if (len) { | |
241 | size_t i; | |
242 | ||
243 | it8712f_wdt_ping(); | |
244 | ||
245 | expect_close = 0; | |
246 | for (i = 0; i < len; ++i) { | |
247 | char c; | |
7944d3a5 | 248 | if (get_user(c, data + i)) |
38ff6fd2 JBD |
249 | return -EFAULT; |
250 | if (c == 'V') | |
251 | expect_close = 42; | |
252 | } | |
253 | } | |
254 | ||
255 | return len; | |
256 | } | |
257 | ||
d6547378 AC |
258 | static long it8712f_wdt_ioctl(struct file *file, unsigned int cmd, |
259 | unsigned long arg) | |
38ff6fd2 JBD |
260 | { |
261 | void __user *argp = (void __user *)arg; | |
262 | int __user *p = argp; | |
42747d71 | 263 | static const struct watchdog_info ident = { |
38ff6fd2 JBD |
264 | .identity = "IT8712F Watchdog", |
265 | .firmware_version = 1, | |
e73a7802 WVS |
266 | .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | |
267 | WDIOF_MAGICCLOSE, | |
38ff6fd2 | 268 | }; |
5e699608 | 269 | int value; |
a134b825 | 270 | int ret; |
38ff6fd2 JBD |
271 | |
272 | switch (cmd) { | |
38ff6fd2 JBD |
273 | case WDIOC_GETSUPPORT: |
274 | if (copy_to_user(argp, &ident, sizeof(ident))) | |
275 | return -EFAULT; | |
276 | return 0; | |
277 | case WDIOC_GETSTATUS: | |
a134b825 NG |
278 | ret = superio_enter(); |
279 | if (ret) | |
280 | return ret; | |
5e699608 AP |
281 | superio_select(LDN_GPIO); |
282 | ||
283 | value = it8712f_wdt_get_status(); | |
284 | ||
285 | superio_exit(); | |
286 | ||
287 | return put_user(value, p); | |
38ff6fd2 JBD |
288 | case WDIOC_GETBOOTSTATUS: |
289 | return put_user(0, p); | |
290 | case WDIOC_KEEPALIVE: | |
291 | it8712f_wdt_ping(); | |
292 | return 0; | |
293 | case WDIOC_SETTIMEOUT: | |
5e699608 | 294 | if (get_user(value, p)) |
38ff6fd2 | 295 | return -EFAULT; |
5e699608 AP |
296 | if (value < 1) |
297 | return -EINVAL; | |
298 | if (value > (max_units * 60)) | |
38ff6fd2 | 299 | return -EINVAL; |
5e699608 | 300 | margin = value; |
a134b825 NG |
301 | ret = superio_enter(); |
302 | if (ret) | |
303 | return ret; | |
38ff6fd2 JBD |
304 | superio_select(LDN_GPIO); |
305 | ||
306 | it8712f_wdt_update_margin(); | |
307 | ||
308 | superio_exit(); | |
309 | it8712f_wdt_ping(); | |
5e699608 | 310 | /* Fall through */ |
38ff6fd2 JBD |
311 | case WDIOC_GETTIMEOUT: |
312 | if (put_user(margin, p)) | |
313 | return -EFAULT; | |
314 | return 0; | |
0c06090c WVS |
315 | default: |
316 | return -ENOTTY; | |
38ff6fd2 JBD |
317 | } |
318 | } | |
319 | ||
d6547378 | 320 | static int it8712f_wdt_open(struct inode *inode, struct file *file) |
38ff6fd2 | 321 | { |
a134b825 | 322 | int ret; |
38ff6fd2 | 323 | /* only allow one at a time */ |
d6547378 | 324 | if (test_and_set_bit(0, &wdt_open)) |
38ff6fd2 | 325 | return -EBUSY; |
a134b825 NG |
326 | |
327 | ret = it8712f_wdt_enable(); | |
328 | if (ret) | |
329 | return ret; | |
38ff6fd2 JBD |
330 | return nonseekable_open(inode, file); |
331 | } | |
332 | ||
d6547378 | 333 | static int it8712f_wdt_release(struct inode *inode, struct file *file) |
38ff6fd2 JBD |
334 | { |
335 | if (expect_close != 42) { | |
27c766aa | 336 | pr_warn("watchdog device closed unexpectedly, will not disable the watchdog timer\n"); |
38ff6fd2 | 337 | } else if (!nowayout) { |
a134b825 | 338 | if (it8712f_wdt_disable()) |
27c766aa | 339 | pr_warn("Watchdog disable failed\n"); |
38ff6fd2 JBD |
340 | } |
341 | expect_close = 0; | |
d6547378 | 342 | clear_bit(0, &wdt_open); |
38ff6fd2 JBD |
343 | |
344 | return 0; | |
345 | } | |
346 | ||
b47a166e | 347 | static const struct file_operations it8712f_wdt_fops = { |
38ff6fd2 JBD |
348 | .owner = THIS_MODULE, |
349 | .llseek = no_llseek, | |
350 | .write = it8712f_wdt_write, | |
d6547378 | 351 | .unlocked_ioctl = it8712f_wdt_ioctl, |
38ff6fd2 JBD |
352 | .open = it8712f_wdt_open, |
353 | .release = it8712f_wdt_release, | |
354 | }; | |
355 | ||
356 | static struct miscdevice it8712f_wdt_miscdev = { | |
357 | .minor = WATCHDOG_MINOR, | |
358 | .name = "watchdog", | |
359 | .fops = &it8712f_wdt_fops, | |
360 | }; | |
361 | ||
d6547378 | 362 | static int __init it8712f_wdt_find(unsigned short *address) |
38ff6fd2 JBD |
363 | { |
364 | int err = -ENODEV; | |
365 | int chip_type; | |
a134b825 NG |
366 | int ret = superio_enter(); |
367 | if (ret) | |
368 | return ret; | |
38ff6fd2 | 369 | |
38ff6fd2 JBD |
370 | chip_type = superio_inw(DEVID); |
371 | if (chip_type != IT8712F_DEVID) | |
372 | goto exit; | |
373 | ||
374 | superio_select(LDN_GAME); | |
375 | superio_outb(1, ACT_REG); | |
376 | if (!(superio_inb(ACT_REG) & 0x01)) { | |
27c766aa | 377 | pr_err("Device not activated, skipping\n"); |
38ff6fd2 JBD |
378 | goto exit; |
379 | } | |
380 | ||
381 | *address = superio_inw(BASE_REG); | |
382 | if (*address == 0) { | |
27c766aa | 383 | pr_err("Base address not set, skipping\n"); |
38ff6fd2 JBD |
384 | goto exit; |
385 | } | |
386 | ||
387 | err = 0; | |
5e699608 AP |
388 | revision = superio_inb(DEVREV) & 0x0f; |
389 | ||
390 | /* Later revisions have 16-bit values per datasheet 0.9.1 */ | |
391 | if (revision >= 0x08) | |
392 | max_units = 65535; | |
393 | ||
394 | if (margin > (max_units * 60)) | |
395 | margin = (max_units * 60); | |
396 | ||
27c766aa | 397 | pr_info("Found IT%04xF chip revision %d - using DogFood address 0x%x\n", |
5e699608 | 398 | chip_type, revision, *address); |
38ff6fd2 JBD |
399 | |
400 | exit: | |
401 | superio_exit(); | |
402 | return err; | |
403 | } | |
404 | ||
d6547378 | 405 | static int __init it8712f_wdt_init(void) |
38ff6fd2 JBD |
406 | { |
407 | int err = 0; | |
408 | ||
38ff6fd2 JBD |
409 | if (it8712f_wdt_find(&address)) |
410 | return -ENODEV; | |
411 | ||
412 | if (!request_region(address, 1, "IT8712F Watchdog")) { | |
27c766aa | 413 | pr_warn("watchdog I/O region busy\n"); |
38ff6fd2 JBD |
414 | return -EBUSY; |
415 | } | |
416 | ||
a134b825 NG |
417 | err = it8712f_wdt_disable(); |
418 | if (err) { | |
27c766aa | 419 | pr_err("unable to disable watchdog timer\n"); |
a134b825 NG |
420 | goto out; |
421 | } | |
38ff6fd2 | 422 | |
38ff6fd2 JBD |
423 | err = register_reboot_notifier(&it8712f_wdt_notifier); |
424 | if (err) { | |
27c766aa | 425 | pr_err("unable to register reboot notifier\n"); |
38ff6fd2 JBD |
426 | goto out; |
427 | } | |
428 | ||
429 | err = misc_register(&it8712f_wdt_miscdev); | |
430 | if (err) { | |
27c766aa JP |
431 | pr_err("cannot register miscdev on minor=%d (err=%d)\n", |
432 | WATCHDOG_MINOR, err); | |
38ff6fd2 JBD |
433 | goto reboot_out; |
434 | } | |
435 | ||
436 | return 0; | |
437 | ||
438 | ||
439 | reboot_out: | |
440 | unregister_reboot_notifier(&it8712f_wdt_notifier); | |
441 | out: | |
442 | release_region(address, 1); | |
443 | return err; | |
444 | } | |
445 | ||
d6547378 | 446 | static void __exit it8712f_wdt_exit(void) |
38ff6fd2 JBD |
447 | { |
448 | misc_deregister(&it8712f_wdt_miscdev); | |
449 | unregister_reboot_notifier(&it8712f_wdt_notifier); | |
450 | release_region(address, 1); | |
451 | } | |
452 | ||
453 | module_init(it8712f_wdt_init); | |
454 | module_exit(it8712f_wdt_exit); |