Commit | Line | Data |
---|---|---|
2874c5fd | 1 | // SPDX-License-Identifier: GPL-2.0-or-later |
1da177e4 LT |
2 | /* |
3 | * National Semiconductor PC87307/PC97307 (ala SC1200) WDT driver | |
4 | * (c) Copyright 2002 Zwane Mwaikambo <zwane@commfireservices.com>, | |
5 | * All Rights Reserved. | |
6 | * Based on wdt.c and wdt977.c by Alan Cox and Woody Suwalski respectively. | |
7 | * | |
1da177e4 LT |
8 | * The author(s) of this software shall not be held liable for damages |
9 | * of any nature resulting due to the use of this software. This | |
10 | * software is provided AS-IS with no warranties. | |
11 | * | |
12 | * Changelog: | |
13 | * 20020220 Zwane Mwaikambo Code based on datasheet, no hardware. | |
103a1d5c AC |
14 | * 20020221 Zwane Mwaikambo Cleanups as suggested by Jeff Garzik |
15 | * and Alan Cox. | |
1da177e4 LT |
16 | * 20020222 Zwane Mwaikambo Added probing. |
17 | * 20020225 Zwane Mwaikambo Added ISAPNP support. | |
18 | * 20020412 Rob Radez Broke out start/stop functions | |
103a1d5c AC |
19 | * <rob@osinvestor.com> Return proper status instead of |
20 | * temperature warning | |
21 | * Add WDIOC_GETBOOTSTATUS and | |
22 | * WDIOC_SETOPTIONS ioctls | |
1da177e4 | 23 | * Fix CONFIG_WATCHDOG_NOWAYOUT |
103a1d5c AC |
24 | * 20020530 Joel Becker Add Matt Domsch's nowayout module |
25 | * option | |
1da177e4 | 26 | * 20030116 Adam Belay Updated to the latest pnp code |
1da177e4 LT |
27 | */ |
28 | ||
27c766aa JP |
29 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
30 | ||
1da177e4 LT |
31 | #include <linux/module.h> |
32 | #include <linux/moduleparam.h> | |
33 | #include <linux/miscdevice.h> | |
34 | #include <linux/watchdog.h> | |
35 | #include <linux/ioport.h> | |
36 | #include <linux/spinlock.h> | |
37 | #include <linux/notifier.h> | |
38 | #include <linux/reboot.h> | |
39 | #include <linux/init.h> | |
40 | #include <linux/pnp.h> | |
41 | #include <linux/fs.h> | |
6188e10d | 42 | #include <linux/semaphore.h> |
103a1d5c AC |
43 | #include <linux/io.h> |
44 | #include <linux/uaccess.h> | |
1da177e4 LT |
45 | |
46 | #define SC1200_MODULE_VER "build 20020303" | |
47 | #define SC1200_MODULE_NAME "sc1200wdt" | |
1da177e4 LT |
48 | |
49 | #define MAX_TIMEOUT 255 /* 255 minutes */ | |
50 | #define PMIR (io) /* Power Management Index Register */ | |
51 | #define PMDR (io+1) /* Power Management Data Register */ | |
52 | ||
53 | /* Data Register indexes */ | |
54 | #define FER1 0x00 /* Function enable register 1 */ | |
55 | #define FER2 0x01 /* Function enable register 2 */ | |
56 | #define PMC1 0x02 /* Power Management Ctrl 1 */ | |
57 | #define PMC2 0x03 /* Power Management Ctrl 2 */ | |
58 | #define PMC3 0x04 /* Power Management Ctrl 3 */ | |
59 | #define WDTO 0x05 /* Watchdog timeout register */ | |
60 | #define WDCF 0x06 /* Watchdog config register */ | |
61 | #define WDST 0x07 /* Watchdog status register */ | |
62 | ||
63 | /* WDCF bitfields - which devices assert WDO */ | |
64 | #define KBC_IRQ 0x01 /* Keyboard Controller */ | |
65 | #define MSE_IRQ 0x02 /* Mouse */ | |
66 | #define UART1_IRQ 0x03 /* Serial0 */ | |
67 | #define UART2_IRQ 0x04 /* Serial1 */ | |
68 | /* 5 -7 are reserved */ | |
69 | ||
1da177e4 LT |
70 | static int timeout = 1; |
71 | static int io = -1; | |
72 | static int io_len = 2; /* for non plug and play */ | |
103a1d5c | 73 | static unsigned long open_flag; |
1da177e4 | 74 | static char expect_close; |
c7dfd0cc | 75 | static DEFINE_SPINLOCK(sc1200wdt_lock); /* io port access serialisation */ |
1da177e4 LT |
76 | |
77 | #if defined CONFIG_PNP | |
78 | static int isapnp = 1; | |
79 | static struct pnp_dev *wdt_dev; | |
80 | ||
81 | module_param(isapnp, int, 0); | |
103a1d5c AC |
82 | MODULE_PARM_DESC(isapnp, |
83 | "When set to 0 driver ISA PnP support will be disabled"); | |
1da177e4 LT |
84 | #endif |
85 | ||
5d1c93ce | 86 | module_param_hw(io, int, ioport, 0); |
1da177e4 LT |
87 | MODULE_PARM_DESC(io, "io port"); |
88 | module_param(timeout, int, 0); | |
89 | MODULE_PARM_DESC(timeout, "range is 0-255 minutes, default is 1"); | |
90 | ||
86a1e189 WVS |
91 | static bool nowayout = WATCHDOG_NOWAYOUT; |
92 | module_param(nowayout, bool, 0); | |
103a1d5c AC |
93 | MODULE_PARM_DESC(nowayout, |
94 | "Watchdog cannot be stopped once started (default=" | |
95 | __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); | |
1da177e4 LT |
96 | |
97 | ||
98 | ||
99 | /* Read from Data Register */ | |
103a1d5c AC |
100 | static inline void __sc1200wdt_read_data(unsigned char index, |
101 | unsigned char *data) | |
1da177e4 | 102 | { |
1da177e4 LT |
103 | outb_p(index, PMIR); |
104 | *data = inb(PMDR); | |
1da177e4 LT |
105 | } |
106 | ||
103a1d5c AC |
107 | static void sc1200wdt_read_data(unsigned char index, unsigned char *data) |
108 | { | |
109 | spin_lock(&sc1200wdt_lock); | |
110 | __sc1200wdt_read_data(index, data); | |
111 | spin_unlock(&sc1200wdt_lock); | |
112 | } | |
1da177e4 LT |
113 | |
114 | /* Write to Data Register */ | |
103a1d5c AC |
115 | static inline void __sc1200wdt_write_data(unsigned char index, |
116 | unsigned char data) | |
1da177e4 | 117 | { |
1da177e4 LT |
118 | outb_p(index, PMIR); |
119 | outb(data, PMDR); | |
103a1d5c AC |
120 | } |
121 | ||
122 | static inline void sc1200wdt_write_data(unsigned char index, | |
123 | unsigned char data) | |
124 | { | |
125 | spin_lock(&sc1200wdt_lock); | |
126 | __sc1200wdt_write_data(index, data); | |
1da177e4 LT |
127 | spin_unlock(&sc1200wdt_lock); |
128 | } | |
129 | ||
130 | ||
131 | static void sc1200wdt_start(void) | |
132 | { | |
133 | unsigned char reg; | |
103a1d5c | 134 | spin_lock(&sc1200wdt_lock); |
1da177e4 | 135 | |
103a1d5c | 136 | __sc1200wdt_read_data(WDCF, ®); |
1da177e4 LT |
137 | /* assert WDO when any of the following interrupts are triggered too */ |
138 | reg |= (KBC_IRQ | MSE_IRQ | UART1_IRQ | UART2_IRQ); | |
103a1d5c | 139 | __sc1200wdt_write_data(WDCF, reg); |
1da177e4 | 140 | /* set the timeout and get the ball rolling */ |
103a1d5c | 141 | __sc1200wdt_write_data(WDTO, timeout); |
1da177e4 | 142 | |
103a1d5c AC |
143 | spin_unlock(&sc1200wdt_lock); |
144 | } | |
1da177e4 LT |
145 | |
146 | static void sc1200wdt_stop(void) | |
147 | { | |
148 | sc1200wdt_write_data(WDTO, 0); | |
149 | } | |
150 | ||
1da177e4 LT |
151 | /* This returns the status of the WDO signal, inactive high. */ |
152 | static inline int sc1200wdt_status(void) | |
153 | { | |
154 | unsigned char ret; | |
155 | ||
156 | sc1200wdt_read_data(WDST, &ret); | |
157 | /* If the bit is inactive, the watchdog is enabled, so return | |
158 | * KEEPALIVEPING which is a bit of a kludge because there's nothing | |
159 | * else for enabled/disabled status | |
160 | */ | |
103a1d5c | 161 | return (ret & 0x01) ? 0 : WDIOF_KEEPALIVEPING; |
1da177e4 LT |
162 | } |
163 | ||
1da177e4 LT |
164 | static int sc1200wdt_open(struct inode *inode, struct file *file) |
165 | { | |
1da177e4 | 166 | /* allow one at a time */ |
103a1d5c | 167 | if (test_and_set_bit(0, &open_flag)) |
1da177e4 LT |
168 | return -EBUSY; |
169 | ||
170 | if (timeout > MAX_TIMEOUT) | |
171 | timeout = MAX_TIMEOUT; | |
172 | ||
173 | sc1200wdt_start(); | |
27c766aa | 174 | pr_info("Watchdog enabled, timeout = %d min(s)", timeout); |
1da177e4 | 175 | |
c5bf68fe | 176 | return stream_open(inode, file); |
1da177e4 LT |
177 | } |
178 | ||
179 | ||
103a1d5c AC |
180 | static long sc1200wdt_ioctl(struct file *file, unsigned int cmd, |
181 | unsigned long arg) | |
1da177e4 LT |
182 | { |
183 | int new_timeout; | |
184 | void __user *argp = (void __user *)arg; | |
185 | int __user *p = argp; | |
103a1d5c AC |
186 | static const struct watchdog_info ident = { |
187 | .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | | |
188 | WDIOF_MAGICCLOSE, | |
1da177e4 LT |
189 | .firmware_version = 0, |
190 | .identity = "PC87307/PC97307", | |
191 | }; | |
192 | ||
193 | switch (cmd) { | |
103a1d5c | 194 | case WDIOC_GETSUPPORT: |
e04ab958 | 195 | if (copy_to_user(argp, &ident, sizeof(ident))) |
103a1d5c AC |
196 | return -EFAULT; |
197 | return 0; | |
1da177e4 | 198 | |
103a1d5c AC |
199 | case WDIOC_GETSTATUS: |
200 | return put_user(sc1200wdt_status(), p); | |
1da177e4 | 201 | |
103a1d5c AC |
202 | case WDIOC_GETBOOTSTATUS: |
203 | return put_user(0, p); | |
1da177e4 | 204 | |
103a1d5c AC |
205 | case WDIOC_SETOPTIONS: |
206 | { | |
207 | int options, retval = -EINVAL; | |
1da177e4 | 208 | |
103a1d5c AC |
209 | if (get_user(options, p)) |
210 | return -EFAULT; | |
1da177e4 | 211 | |
103a1d5c AC |
212 | if (options & WDIOS_DISABLECARD) { |
213 | sc1200wdt_stop(); | |
214 | retval = 0; | |
215 | } | |
1da177e4 | 216 | |
103a1d5c AC |
217 | if (options & WDIOS_ENABLECARD) { |
218 | sc1200wdt_start(); | |
219 | retval = 0; | |
1da177e4 | 220 | } |
103a1d5c AC |
221 | |
222 | return retval; | |
223 | } | |
0c06090c WVS |
224 | case WDIOC_KEEPALIVE: |
225 | sc1200wdt_write_data(WDTO, timeout); | |
226 | return 0; | |
227 | ||
228 | case WDIOC_SETTIMEOUT: | |
229 | if (get_user(new_timeout, p)) | |
230 | return -EFAULT; | |
231 | /* the API states this is given in secs */ | |
232 | new_timeout /= 60; | |
233 | if (new_timeout < 0 || new_timeout > MAX_TIMEOUT) | |
234 | return -EINVAL; | |
235 | timeout = new_timeout; | |
236 | sc1200wdt_write_data(WDTO, timeout); | |
51c802f5 | 237 | /* fall through - and return the new timeout */ |
0c06090c WVS |
238 | |
239 | case WDIOC_GETTIMEOUT: | |
240 | return put_user(timeout * 60, p); | |
241 | ||
103a1d5c AC |
242 | default: |
243 | return -ENOTTY; | |
1da177e4 LT |
244 | } |
245 | } | |
246 | ||
247 | ||
248 | static int sc1200wdt_release(struct inode *inode, struct file *file) | |
249 | { | |
250 | if (expect_close == 42) { | |
251 | sc1200wdt_stop(); | |
27c766aa | 252 | pr_info("Watchdog disabled\n"); |
1da177e4 LT |
253 | } else { |
254 | sc1200wdt_write_data(WDTO, timeout); | |
27c766aa | 255 | pr_crit("Unexpected close!, timeout = %d min(s)\n", timeout); |
1da177e4 | 256 | } |
103a1d5c | 257 | clear_bit(0, &open_flag); |
1da177e4 LT |
258 | expect_close = 0; |
259 | ||
260 | return 0; | |
261 | } | |
262 | ||
263 | ||
103a1d5c AC |
264 | static ssize_t sc1200wdt_write(struct file *file, const char __user *data, |
265 | size_t len, loff_t *ppos) | |
1da177e4 LT |
266 | { |
267 | if (len) { | |
268 | if (!nowayout) { | |
269 | size_t i; | |
270 | ||
271 | expect_close = 0; | |
272 | ||
273 | for (i = 0; i != len; i++) { | |
274 | char c; | |
275 | ||
7944d3a5 | 276 | if (get_user(c, data + i)) |
1da177e4 LT |
277 | return -EFAULT; |
278 | if (c == 'V') | |
279 | expect_close = 42; | |
280 | } | |
281 | } | |
282 | ||
283 | sc1200wdt_write_data(WDTO, timeout); | |
284 | return len; | |
285 | } | |
286 | ||
287 | return 0; | |
288 | } | |
289 | ||
290 | ||
103a1d5c AC |
291 | static int sc1200wdt_notify_sys(struct notifier_block *this, |
292 | unsigned long code, void *unused) | |
1da177e4 LT |
293 | { |
294 | if (code == SYS_DOWN || code == SYS_HALT) | |
295 | sc1200wdt_stop(); | |
296 | ||
297 | return NOTIFY_DONE; | |
298 | } | |
299 | ||
300 | ||
103a1d5c | 301 | static struct notifier_block sc1200wdt_notifier = { |
1da177e4 LT |
302 | .notifier_call = sc1200wdt_notify_sys, |
303 | }; | |
304 | ||
103a1d5c | 305 | static const struct file_operations sc1200wdt_fops = { |
1da177e4 LT |
306 | .owner = THIS_MODULE, |
307 | .llseek = no_llseek, | |
308 | .write = sc1200wdt_write, | |
103a1d5c | 309 | .unlocked_ioctl = sc1200wdt_ioctl, |
1da177e4 LT |
310 | .open = sc1200wdt_open, |
311 | .release = sc1200wdt_release, | |
312 | }; | |
313 | ||
103a1d5c | 314 | static struct miscdevice sc1200wdt_miscdev = { |
1da177e4 LT |
315 | .minor = WATCHDOG_MINOR, |
316 | .name = "watchdog", | |
317 | .fops = &sc1200wdt_fops, | |
318 | }; | |
319 | ||
320 | ||
321 | static int __init sc1200wdt_probe(void) | |
322 | { | |
323 | /* The probe works by reading the PMC3 register's default value of 0x0e | |
324 | * there is one caveat, if the device disables the parallel port or any | |
325 | * of the UARTs we won't be able to detect it. | |
103a1d5c AC |
326 | * NB. This could be done with accuracy by reading the SID registers, |
327 | * but we don't have access to those io regions. | |
1da177e4 LT |
328 | */ |
329 | ||
330 | unsigned char reg; | |
331 | ||
332 | sc1200wdt_read_data(PMC3, ®); | |
103a1d5c | 333 | reg &= 0x0f; /* we don't want the UART busy bits */ |
1da177e4 LT |
334 | return (reg == 0x0e) ? 0 : -ENODEV; |
335 | } | |
336 | ||
337 | ||
338 | #if defined CONFIG_PNP | |
339 | ||
39ad8089 | 340 | static const struct pnp_device_id scl200wdt_pnp_devices[] = { |
1da177e4 LT |
341 | /* National Semiconductor PC87307/PC97307 watchdog component */ |
342 | {.id = "NSC0800", .driver_data = 0}, | |
343 | {.id = ""}, | |
344 | }; | |
345 | ||
103a1d5c AC |
346 | static int scl200wdt_pnp_probe(struct pnp_dev *dev, |
347 | const struct pnp_device_id *dev_id) | |
1da177e4 LT |
348 | { |
349 | /* this driver only supports one card at a time */ | |
350 | if (wdt_dev || !isapnp) | |
351 | return -EBUSY; | |
352 | ||
353 | wdt_dev = dev; | |
354 | io = pnp_port_start(wdt_dev, 0); | |
355 | io_len = pnp_port_len(wdt_dev, 0); | |
356 | ||
357 | if (!request_region(io, io_len, SC1200_MODULE_NAME)) { | |
27c766aa | 358 | pr_err("Unable to register IO port %#x\n", io); |
1da177e4 LT |
359 | return -EBUSY; |
360 | } | |
361 | ||
27c766aa | 362 | pr_info("PnP device found at io port %#x/%d\n", io, io_len); |
1da177e4 LT |
363 | return 0; |
364 | } | |
365 | ||
103a1d5c | 366 | static void scl200wdt_pnp_remove(struct pnp_dev *dev) |
1da177e4 | 367 | { |
103a1d5c | 368 | if (wdt_dev) { |
1da177e4 LT |
369 | release_region(io, io_len); |
370 | wdt_dev = NULL; | |
371 | } | |
372 | } | |
373 | ||
374 | static struct pnp_driver scl200wdt_pnp_driver = { | |
375 | .name = "scl200wdt", | |
376 | .id_table = scl200wdt_pnp_devices, | |
377 | .probe = scl200wdt_pnp_probe, | |
378 | .remove = scl200wdt_pnp_remove, | |
379 | }; | |
380 | ||
381 | #endif /* CONFIG_PNP */ | |
382 | ||
383 | ||
384 | static int __init sc1200wdt_init(void) | |
385 | { | |
386 | int ret; | |
387 | ||
27c766aa | 388 | pr_info("%s\n", SC1200_MODULE_VER); |
1da177e4 | 389 | |
1da177e4 LT |
390 | #if defined CONFIG_PNP |
391 | if (isapnp) { | |
392 | ret = pnp_register_driver(&scl200wdt_pnp_driver); | |
393 | if (ret) | |
394 | goto out_clean; | |
395 | } | |
396 | #endif | |
397 | ||
398 | if (io == -1) { | |
27c766aa | 399 | pr_err("io parameter must be specified\n"); |
1da177e4 | 400 | ret = -EINVAL; |
150ed8ed | 401 | goto out_pnp; |
1da177e4 LT |
402 | } |
403 | ||
404 | #if defined CONFIG_PNP | |
405 | /* now that the user has specified an IO port and we haven't detected | |
406 | * any devices, disable pnp support */ | |
dace8bbf A |
407 | if (isapnp) |
408 | pnp_unregister_driver(&scl200wdt_pnp_driver); | |
1da177e4 | 409 | isapnp = 0; |
1da177e4 LT |
410 | #endif |
411 | ||
412 | if (!request_region(io, io_len, SC1200_MODULE_NAME)) { | |
27c766aa | 413 | pr_err("Unable to register IO port %#x\n", io); |
1da177e4 | 414 | ret = -EBUSY; |
150ed8ed | 415 | goto out_pnp; |
1da177e4 LT |
416 | } |
417 | ||
418 | ret = sc1200wdt_probe(); | |
419 | if (ret) | |
420 | goto out_io; | |
421 | ||
422 | ret = register_reboot_notifier(&sc1200wdt_notifier); | |
423 | if (ret) { | |
27c766aa | 424 | pr_err("Unable to register reboot notifier err = %d\n", ret); |
1da177e4 LT |
425 | goto out_io; |
426 | } | |
427 | ||
428 | ret = misc_register(&sc1200wdt_miscdev); | |
429 | if (ret) { | |
27c766aa JP |
430 | pr_err("Unable to register miscdev on minor %d\n", |
431 | WATCHDOG_MINOR); | |
1da177e4 LT |
432 | goto out_rbt; |
433 | } | |
434 | ||
435 | /* ret = 0 */ | |
436 | ||
437 | out_clean: | |
438 | return ret; | |
439 | ||
440 | out_rbt: | |
441 | unregister_reboot_notifier(&sc1200wdt_notifier); | |
442 | ||
443 | out_io: | |
444 | release_region(io, io_len); | |
445 | ||
150ed8ed AM |
446 | out_pnp: |
447 | #if defined CONFIG_PNP | |
448 | if (isapnp) | |
449 | pnp_unregister_driver(&scl200wdt_pnp_driver); | |
450 | #endif | |
1da177e4 LT |
451 | goto out_clean; |
452 | } | |
453 | ||
454 | ||
455 | static void __exit sc1200wdt_exit(void) | |
456 | { | |
457 | misc_deregister(&sc1200wdt_miscdev); | |
458 | unregister_reboot_notifier(&sc1200wdt_notifier); | |
459 | ||
460 | #if defined CONFIG_PNP | |
103a1d5c | 461 | if (isapnp) |
1da177e4 LT |
462 | pnp_unregister_driver(&scl200wdt_pnp_driver); |
463 | else | |
464 | #endif | |
465 | release_region(io, io_len); | |
466 | } | |
467 | ||
468 | module_init(sc1200wdt_init); | |
469 | module_exit(sc1200wdt_exit); | |
470 | ||
471 | MODULE_AUTHOR("Zwane Mwaikambo <zwane@commfireservices.com>"); | |
143a2e54 WVS |
472 | MODULE_DESCRIPTION( |
473 | "Driver for National Semiconductor PC87307/PC97307 watchdog component"); | |
1da177e4 | 474 | MODULE_LICENSE("GPL"); |