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1/*
2 * sch311x_wdt.c - Driver for the SCH311x Super-I/O chips
3 * integrated watchdog.
4 *
5 * (c) Copyright 2008 Wim Van Sebroeck <wim@iguana.be>.
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version
10 * 2 of the License, or (at your option) any later version.
11 *
12 * Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
13 * provide warranty for any of this software. This material is
14 * provided "AS-IS" and at no charge.
15 */
16
17/*
18 * Includes, defines, variables, module parameters, ...
19 */
20
21/* Includes */
22#include <linux/module.h> /* For module specific items */
23#include <linux/moduleparam.h> /* For new moduleparam's */
24#include <linux/types.h> /* For standard types (like size_t) */
25#include <linux/errno.h> /* For the -ENODEV/... values */
26#include <linux/kernel.h> /* For printk/... */
27#include <linux/miscdevice.h> /* For MODULE_ALIAS_MISCDEV
28 (WATCHDOG_MINOR) */
29#include <linux/watchdog.h> /* For the watchdog specific items */
30#include <linux/init.h> /* For __init/__exit/... */
31#include <linux/fs.h> /* For file operations */
32#include <linux/platform_device.h> /* For platform_driver framework */
33#include <linux/ioport.h> /* For io-port access */
34#include <linux/spinlock.h> /* For spin_lock/spin_unlock/... */
35#include <linux/uaccess.h> /* For copy_to_user/put_user/... */
36#include <linux/io.h> /* For inb/outb/... */
37
38/* Module and version information */
39#define DRV_NAME "sch311x_wdt"
40#define PFX DRV_NAME ": "
41
42/* Runtime registers */
43#define RESGEN 0x1d
44#define GP60 0x47
45#define WDT_TIME_OUT 0x65
46#define WDT_VAL 0x66
47#define WDT_CFG 0x67
48#define WDT_CTRL 0x68
49
50/* internal variables */
51static unsigned long sch311x_wdt_is_open;
52static char sch311x_wdt_expect_close;
53static struct platform_device *sch311x_wdt_pdev;
54
55static int sch311x_ioports[] = { 0x2e, 0x4e, 0x162e, 0x164e, 0x00 };
56
57static struct { /* The devices private data */
58 /* the Runtime Register base address */
59 unsigned short runtime_reg;
60 /* The card's boot status */
61 int boot_status;
62 /* the lock for io operations */
63 spinlock_t io_lock;
64} sch311x_wdt_data;
65
66/* Module load parameters */
67static unsigned short force_id;
68module_param(force_id, ushort, 0);
69MODULE_PARM_DESC(force_id, "Override the detected device ID");
70
71static unsigned short therm_trip;
72module_param(therm_trip, ushort, 0);
73MODULE_PARM_DESC(therm_trip, "Should a ThermTrip trigger the reset generator");
74
75#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
76static int timeout = WATCHDOG_TIMEOUT; /* in seconds */
77module_param(timeout, int, 0);
78MODULE_PARM_DESC(timeout,
79 "Watchdog timeout in seconds. 1<= timeout <=15300, default="
80 __MODULE_STRING(WATCHDOG_TIMEOUT) ".");
81
82static int nowayout = WATCHDOG_NOWAYOUT;
83module_param(nowayout, int, 0);
84MODULE_PARM_DESC(nowayout,
85 "Watchdog cannot be stopped once started (default="
86 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
87
88/*
89 * Super-IO functions
90 */
91
92static inline void sch311x_sio_enter(int sio_config_port)
93{
94 outb(0x55, sio_config_port);
95}
96
97static inline void sch311x_sio_exit(int sio_config_port)
98{
99 outb(0xaa, sio_config_port);
100}
101
102static inline int sch311x_sio_inb(int sio_config_port, int reg)
103{
104 outb(reg, sio_config_port);
105 return inb(sio_config_port + 1);
106}
107
108static inline void sch311x_sio_outb(int sio_config_port, int reg, int val)
109{
110 outb(reg, sio_config_port);
111 outb(val, sio_config_port + 1);
112}
113
114/*
115 * Watchdog Operations
116 */
117
118static void sch311x_wdt_set_timeout(int t)
119{
120 unsigned char timeout_unit = 0x80;
121
122 /* When new timeout is bigger then 255 seconds, we will use minutes */
123 if (t > 255) {
124 timeout_unit = 0;
125 t /= 60;
126 }
127
128 /* -- Watchdog Timeout --
129 * Bit 0-6 (Reserved)
130 * Bit 7 WDT Time-out Value Units Select
131 * (0 = Minutes, 1 = Seconds)
132 */
133 outb(timeout_unit, sch311x_wdt_data.runtime_reg + WDT_TIME_OUT);
134
135 /* -- Watchdog Timer Time-out Value --
136 * Bit 0-7 Binary coded units (0=Disabled, 1..255)
137 */
138 outb(t, sch311x_wdt_data.runtime_reg + WDT_VAL);
139}
140
141static void sch311x_wdt_start(void)
142{
143 spin_lock(&sch311x_wdt_data.io_lock);
144
145 /* set watchdog's timeout */
146 sch311x_wdt_set_timeout(timeout);
147 /* enable the watchdog */
148 /* -- General Purpose I/O Bit 6.0 --
149 * Bit 0, In/Out: 0 = Output, 1 = Input
150 * Bit 1, Polarity: 0 = No Invert, 1 = Invert
151 * Bit 2-3, Function select: 00 = GPI/O, 01 = LED1, 11 = WDT,
152 * 10 = Either Edge Triggered Intr.4
153 * Bit 4-6 (Reserved)
154 * Bit 7, Output Type: 0 = Push Pull Bit, 1 = Open Drain
155 */
156 outb(0x0e, sch311x_wdt_data.runtime_reg + GP60);
157
158 spin_unlock(&sch311x_wdt_data.io_lock);
159
160}
161
162static void sch311x_wdt_stop(void)
163{
164 spin_lock(&sch311x_wdt_data.io_lock);
165
166 /* stop the watchdog */
167 outb(0x01, sch311x_wdt_data.runtime_reg + GP60);
168 /* disable timeout by setting it to 0 */
169 sch311x_wdt_set_timeout(0);
170
171 spin_unlock(&sch311x_wdt_data.io_lock);
172}
173
174static void sch311x_wdt_keepalive(void)
175{
176 spin_lock(&sch311x_wdt_data.io_lock);
177 sch311x_wdt_set_timeout(timeout);
178 spin_unlock(&sch311x_wdt_data.io_lock);
179}
180
181static int sch311x_wdt_set_heartbeat(int t)
182{
183 if (t < 1 || t > (255*60))
184 return -EINVAL;
185
186 /* When new timeout is bigger then 255 seconds,
187 * we will round up to minutes (with a max of 255) */
188 if (t > 255)
189 t = (((t - 1) / 60) + 1) * 60;
190
191 timeout = t;
192 return 0;
193}
194
195static void sch311x_wdt_get_status(int *status)
196{
197 unsigned char new_status;
198
199 *status = 0;
200
201 spin_lock(&sch311x_wdt_data.io_lock);
202
203 /* -- Watchdog timer control --
204 * Bit 0 Status Bit: 0 = Timer counting, 1 = Timeout occurred
205 * Bit 1 Reserved
206 * Bit 2 Force Timeout: 1 = Forces WD timeout event (self-cleaning)
207 * Bit 3 P20 Force Timeout enabled:
208 * 0 = P20 activity does not generate the WD timeout event
209 * 1 = P20 Allows rising edge of P20, from the keyboard
210 * controller, to force the WD timeout event.
211 * Bit 4-7 Reserved
212 */
213 new_status = inb(sch311x_wdt_data.runtime_reg + WDT_CTRL);
214 if (new_status & 0x01)
215 *status |= WDIOF_CARDRESET;
216
217 spin_unlock(&sch311x_wdt_data.io_lock);
218}
219
220/*
221 * /dev/watchdog handling
222 */
223
224static ssize_t sch311x_wdt_write(struct file *file, const char __user *buf,
225 size_t count, loff_t *ppos)
226{
227 if (count) {
228 if (!nowayout) {
229 size_t i;
230
231 sch311x_wdt_expect_close = 0;
232
233 for (i = 0; i != count; i++) {
234 char c;
235 if (get_user(c, buf + i))
236 return -EFAULT;
237 if (c == 'V')
238 sch311x_wdt_expect_close = 42;
239 }
240 }
241 sch311x_wdt_keepalive();
242 }
243 return count;
244}
245
246static long sch311x_wdt_ioctl(struct file *file, unsigned int cmd,
247 unsigned long arg)
248{
249 int status;
250 int new_timeout;
251 void __user *argp = (void __user *)arg;
252 int __user *p = argp;
253 static const struct watchdog_info ident = {
254 .options = WDIOF_KEEPALIVEPING |
255 WDIOF_SETTIMEOUT |
256 WDIOF_MAGICCLOSE,
257 .firmware_version = 1,
258 .identity = DRV_NAME,
259 };
260
261 switch (cmd) {
262 case WDIOC_GETSUPPORT:
263 if (copy_to_user(argp, &ident, sizeof(ident)))
264 return -EFAULT;
265 break;
266
267 case WDIOC_GETSTATUS:
268 {
269 sch311x_wdt_get_status(&status);
270 return put_user(status, p);
271 }
272 case WDIOC_GETBOOTSTATUS:
273 return put_user(sch311x_wdt_data.boot_status, p);
274
275 case WDIOC_SETOPTIONS:
276 {
277 int options, retval = -EINVAL;
278
279 if (get_user(options, p))
280 return -EFAULT;
281 if (options & WDIOS_DISABLECARD) {
282 sch311x_wdt_stop();
283 retval = 0;
284 }
285 if (options & WDIOS_ENABLECARD) {
286 sch311x_wdt_start();
287 retval = 0;
288 }
289 return retval;
290 }
291 case WDIOC_KEEPALIVE:
292 sch311x_wdt_keepalive();
293 break;
294
295 case WDIOC_SETTIMEOUT:
296 if (get_user(new_timeout, p))
297 return -EFAULT;
298 if (sch311x_wdt_set_heartbeat(new_timeout))
299 return -EINVAL;
300 sch311x_wdt_keepalive();
301 /* Fall */
302 case WDIOC_GETTIMEOUT:
303 return put_user(timeout, p);
304 default:
305 return -ENOTTY;
306 }
307 return 0;
308}
309
310static int sch311x_wdt_open(struct inode *inode, struct file *file)
311{
312 if (test_and_set_bit(0, &sch311x_wdt_is_open))
313 return -EBUSY;
314 /*
315 * Activate
316 */
317 sch311x_wdt_start();
318 return nonseekable_open(inode, file);
319}
320
321static int sch311x_wdt_close(struct inode *inode, struct file *file)
322{
323 if (sch311x_wdt_expect_close == 42) {
324 sch311x_wdt_stop();
325 } else {
326 printk(KERN_CRIT PFX
327 "Unexpected close, not stopping watchdog!\n");
328 sch311x_wdt_keepalive();
329 }
330 clear_bit(0, &sch311x_wdt_is_open);
331 sch311x_wdt_expect_close = 0;
332 return 0;
333}
334
335/*
336 * Kernel Interfaces
337 */
338
339static const struct file_operations sch311x_wdt_fops = {
340 .owner = THIS_MODULE,
341 .llseek = no_llseek,
342 .write = sch311x_wdt_write,
343 .unlocked_ioctl = sch311x_wdt_ioctl,
344 .open = sch311x_wdt_open,
345 .release = sch311x_wdt_close,
346};
347
348static struct miscdevice sch311x_wdt_miscdev = {
349 .minor = WATCHDOG_MINOR,
350 .name = "watchdog",
351 .fops = &sch311x_wdt_fops,
352};
353
354/*
355 * Init & exit routines
356 */
357
358static int __devinit sch311x_wdt_probe(struct platform_device *pdev)
359{
360 struct device *dev = &pdev->dev;
361 unsigned char val;
362 int err;
363
364 spin_lock_init(&sch311x_wdt_data.io_lock);
365
366 if (!request_region(sch311x_wdt_data.runtime_reg + RESGEN, 1,
367 DRV_NAME)) {
368 dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n",
369 sch311x_wdt_data.runtime_reg + RESGEN,
370 sch311x_wdt_data.runtime_reg + RESGEN);
371 err = -EBUSY;
372 goto exit;
373 }
374
375 if (!request_region(sch311x_wdt_data.runtime_reg + GP60, 1, DRV_NAME)) {
376 dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n",
377 sch311x_wdt_data.runtime_reg + GP60,
378 sch311x_wdt_data.runtime_reg + GP60);
379 err = -EBUSY;
380 goto exit_release_region;
381 }
382
383 if (!request_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4,
384 DRV_NAME)) {
385 dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n",
386 sch311x_wdt_data.runtime_reg + WDT_TIME_OUT,
387 sch311x_wdt_data.runtime_reg + WDT_CTRL);
388 err = -EBUSY;
389 goto exit_release_region2;
390 }
391
392 /* Make sure that the watchdog is not running */
393 sch311x_wdt_stop();
394
395 /* Disable keyboard and mouse interaction and interrupt */
396 /* -- Watchdog timer configuration --
397 * Bit 0 Reserved
398 * Bit 1 Keyboard enable: 0* = No Reset, 1 = Reset WDT upon KBD Intr.
399 * Bit 2 Mouse enable: 0* = No Reset, 1 = Reset WDT upon Mouse Intr
400 * Bit 3 Reserved
401 * Bit 4-7 WDT Interrupt Mapping: (0000* = Disabled,
402 * 0001=IRQ1, 0010=(Invalid), 0011=IRQ3 to 1111=IRQ15)
403 */
404 outb(0, sch311x_wdt_data.runtime_reg + WDT_CFG);
405
406 /* Check that the heartbeat value is within it's range ;
407 * if not reset to the default */
408 if (sch311x_wdt_set_heartbeat(timeout)) {
409 sch311x_wdt_set_heartbeat(WATCHDOG_TIMEOUT);
410 dev_info(dev, "timeout value must be 1<=x<=15300, using %d\n",
411 timeout);
412 }
413
414 /* Get status at boot */
415 sch311x_wdt_get_status(&sch311x_wdt_data.boot_status);
416
417 /* enable watchdog */
418 /* -- Reset Generator --
419 * Bit 0 Enable Watchdog Timer Generation: 0* = Enabled, 1 = Disabled
420 * Bit 1 Thermtrip Source Select: O* = No Source, 1 = Source
421 * Bit 2 WDT2_CTL: WDT input bit
422 * Bit 3-7 Reserved
423 */
424 outb(0, sch311x_wdt_data.runtime_reg + RESGEN);
425 val = therm_trip ? 0x06 : 0x04;
426 outb(val, sch311x_wdt_data.runtime_reg + RESGEN);
427
428 sch311x_wdt_miscdev.parent = dev;
429
430 err = misc_register(&sch311x_wdt_miscdev);
431 if (err != 0) {
432 dev_err(dev, "cannot register miscdev on minor=%d (err=%d)\n",
433 WATCHDOG_MINOR, err);
434 goto exit_release_region3;
435 }
436
437 dev_info(dev,
438 "SMSC SCH311x WDT initialized. timeout=%d sec (nowayout=%d)\n",
439 timeout, nowayout);
440
441 return 0;
442
443exit_release_region3:
444 release_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4);
445exit_release_region2:
446 release_region(sch311x_wdt_data.runtime_reg + GP60, 1);
447exit_release_region:
448 release_region(sch311x_wdt_data.runtime_reg + RESGEN, 1);
449 sch311x_wdt_data.runtime_reg = 0;
450exit:
451 return err;
452}
453
454static int __devexit sch311x_wdt_remove(struct platform_device *pdev)
455{
456 /* Stop the timer before we leave */
457 if (!nowayout)
458 sch311x_wdt_stop();
459
460 /* Deregister */
461 misc_deregister(&sch311x_wdt_miscdev);
462 release_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4);
463 release_region(sch311x_wdt_data.runtime_reg + GP60, 1);
464 release_region(sch311x_wdt_data.runtime_reg + RESGEN, 1);
465 sch311x_wdt_data.runtime_reg = 0;
466 return 0;
467}
468
469static void sch311x_wdt_shutdown(struct platform_device *dev)
470{
471 /* Turn the WDT off if we have a soft shutdown */
472 sch311x_wdt_stop();
473}
474
475static struct platform_driver sch311x_wdt_driver = {
476 .probe = sch311x_wdt_probe,
477 .remove = __devexit_p(sch311x_wdt_remove),
478 .shutdown = sch311x_wdt_shutdown,
479 .driver = {
480 .owner = THIS_MODULE,
481 .name = DRV_NAME,
482 },
483};
484
485static int __init sch311x_detect(int sio_config_port, unsigned short *addr)
486{
487 int err = 0, reg;
488 unsigned short base_addr;
489 unsigned char dev_id;
490
491 sch311x_sio_enter(sio_config_port);
492
493 /* Check device ID. We currently know about:
494 * SCH3112 (0x7c), SCH3114 (0x7d), and SCH3116 (0x7f). */
495 reg = force_id ? force_id : sch311x_sio_inb(sio_config_port, 0x20);
496 if (!(reg == 0x7c || reg == 0x7d || reg == 0x7f)) {
497 err = -ENODEV;
498 goto exit;
499 }
500 dev_id = reg == 0x7c ? 2 : reg == 0x7d ? 4 : 6;
501
502 /* Select logical device A (runtime registers) */
503 sch311x_sio_outb(sio_config_port, 0x07, 0x0a);
504
505 /* Check if Logical Device Register is currently active */
506 if ((sch311x_sio_inb(sio_config_port, 0x30) & 0x01) == 0)
507 printk(KERN_INFO PFX "Seems that LDN 0x0a is not active...\n");
508
509 /* Get the base address of the runtime registers */
510 base_addr = (sch311x_sio_inb(sio_config_port, 0x60) << 8) |
511 sch311x_sio_inb(sio_config_port, 0x61);
512 if (!base_addr) {
513 printk(KERN_ERR PFX "Base address not set.\n");
514 err = -ENODEV;
515 goto exit;
516 }
517 *addr = base_addr;
518
519 printk(KERN_INFO PFX "Found an SMSC SCH311%d chip at 0x%04x\n",
520 dev_id, base_addr);
521
522exit:
523 sch311x_sio_exit(sio_config_port);
524 return err;
525}
526
527static int __init sch311x_wdt_init(void)
528{
529 int err, i, found = 0;
530 unsigned short addr = 0;
531
532 for (i = 0; !found && sch311x_ioports[i]; i++)
533 if (sch311x_detect(sch311x_ioports[i], &addr) == 0)
534 found++;
535
536 if (!found)
537 return -ENODEV;
538
539 sch311x_wdt_data.runtime_reg = addr;
540
541 err = platform_driver_register(&sch311x_wdt_driver);
542 if (err)
543 return err;
544
545 sch311x_wdt_pdev = platform_device_register_simple(DRV_NAME, addr,
546 NULL, 0);
547
548 if (IS_ERR(sch311x_wdt_pdev)) {
549 err = PTR_ERR(sch311x_wdt_pdev);
550 goto unreg_platform_driver;
551 }
552
553 return 0;
554
555unreg_platform_driver:
556 platform_driver_unregister(&sch311x_wdt_driver);
557 return err;
558}
559
560static void __exit sch311x_wdt_exit(void)
561{
562 platform_device_unregister(sch311x_wdt_pdev);
563 platform_driver_unregister(&sch311x_wdt_driver);
564}
565
566module_init(sch311x_wdt_init);
567module_exit(sch311x_wdt_exit);
568
569MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
570MODULE_DESCRIPTION("SMSC SCH311x WatchDog Timer Driver");
571MODULE_LICENSE("GPL");
572MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);
573
1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * sch311x_wdt.c - Driver for the SCH311x Super-I/O chips
4 * integrated watchdog.
5 *
6 * (c) Copyright 2008 Wim Van Sebroeck <wim@iguana.be>.
7 *
8 * Neither Wim Van Sebroeck nor Iguana vzw. admit liability nor
9 * provide warranty for any of this software. This material is
10 * provided "AS-IS" and at no charge.
11 */
12
13/*
14 * Includes, defines, variables, module parameters, ...
15 */
16
17#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
18
19/* Includes */
20#include <linux/module.h> /* For module specific items */
21#include <linux/moduleparam.h> /* For new moduleparam's */
22#include <linux/types.h> /* For standard types (like size_t) */
23#include <linux/errno.h> /* For the -ENODEV/... values */
24#include <linux/kernel.h> /* For printk/... */
25#include <linux/miscdevice.h> /* For struct miscdevice */
26#include <linux/watchdog.h> /* For the watchdog specific items */
27#include <linux/init.h> /* For __init/__exit/... */
28#include <linux/fs.h> /* For file operations */
29#include <linux/platform_device.h> /* For platform_driver framework */
30#include <linux/ioport.h> /* For io-port access */
31#include <linux/spinlock.h> /* For spin_lock/spin_unlock/... */
32#include <linux/uaccess.h> /* For copy_to_user/put_user/... */
33#include <linux/io.h> /* For inb/outb/... */
34
35/* Module and version information */
36#define DRV_NAME "sch311x_wdt"
37
38/* Runtime registers */
39#define GP60 0x47
40#define WDT_TIME_OUT 0x65
41#define WDT_VAL 0x66
42#define WDT_CFG 0x67
43#define WDT_CTRL 0x68
44
45/* internal variables */
46static unsigned long sch311x_wdt_is_open;
47static char sch311x_wdt_expect_close;
48static struct platform_device *sch311x_wdt_pdev;
49
50static int sch311x_ioports[] = { 0x2e, 0x4e, 0x162e, 0x164e, 0x00 };
51
52static struct { /* The devices private data */
53 /* the Runtime Register base address */
54 unsigned short runtime_reg;
55 /* The card's boot status */
56 int boot_status;
57 /* the lock for io operations */
58 spinlock_t io_lock;
59} sch311x_wdt_data;
60
61/* Module load parameters */
62static unsigned short force_id;
63module_param(force_id, ushort, 0);
64MODULE_PARM_DESC(force_id, "Override the detected device ID");
65
66#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
67static int timeout = WATCHDOG_TIMEOUT; /* in seconds */
68module_param(timeout, int, 0);
69MODULE_PARM_DESC(timeout,
70 "Watchdog timeout in seconds. 1<= timeout <=15300, default="
71 __MODULE_STRING(WATCHDOG_TIMEOUT) ".");
72
73static bool nowayout = WATCHDOG_NOWAYOUT;
74module_param(nowayout, bool, 0);
75MODULE_PARM_DESC(nowayout,
76 "Watchdog cannot be stopped once started (default="
77 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
78
79/*
80 * Super-IO functions
81 */
82
83static inline void sch311x_sio_enter(int sio_config_port)
84{
85 outb(0x55, sio_config_port);
86}
87
88static inline void sch311x_sio_exit(int sio_config_port)
89{
90 outb(0xaa, sio_config_port);
91}
92
93static inline int sch311x_sio_inb(int sio_config_port, int reg)
94{
95 outb(reg, sio_config_port);
96 return inb(sio_config_port + 1);
97}
98
99static inline void sch311x_sio_outb(int sio_config_port, int reg, int val)
100{
101 outb(reg, sio_config_port);
102 outb(val, sio_config_port + 1);
103}
104
105/*
106 * Watchdog Operations
107 */
108
109static void sch311x_wdt_set_timeout(int t)
110{
111 unsigned char timeout_unit = 0x80;
112
113 /* When new timeout is bigger then 255 seconds, we will use minutes */
114 if (t > 255) {
115 timeout_unit = 0;
116 t /= 60;
117 }
118
119 /* -- Watchdog Timeout --
120 * Bit 0-6 (Reserved)
121 * Bit 7 WDT Time-out Value Units Select
122 * (0 = Minutes, 1 = Seconds)
123 */
124 outb(timeout_unit, sch311x_wdt_data.runtime_reg + WDT_TIME_OUT);
125
126 /* -- Watchdog Timer Time-out Value --
127 * Bit 0-7 Binary coded units (0=Disabled, 1..255)
128 */
129 outb(t, sch311x_wdt_data.runtime_reg + WDT_VAL);
130}
131
132static void sch311x_wdt_start(void)
133{
134 unsigned char t;
135
136 spin_lock(&sch311x_wdt_data.io_lock);
137
138 /* set watchdog's timeout */
139 sch311x_wdt_set_timeout(timeout);
140 /* enable the watchdog */
141 /* -- General Purpose I/O Bit 6.0 --
142 * Bit 0, In/Out: 0 = Output, 1 = Input
143 * Bit 1, Polarity: 0 = No Invert, 1 = Invert
144 * Bit 2-3, Function select: 00 = GPI/O, 01 = LED1, 11 = WDT,
145 * 10 = Either Edge Triggered Intr.4
146 * Bit 4-6 (Reserved)
147 * Bit 7, Output Type: 0 = Push Pull Bit, 1 = Open Drain
148 */
149 t = inb(sch311x_wdt_data.runtime_reg + GP60);
150 outb((t & ~0x0d) | 0x0c, sch311x_wdt_data.runtime_reg + GP60);
151
152 spin_unlock(&sch311x_wdt_data.io_lock);
153
154}
155
156static void sch311x_wdt_stop(void)
157{
158 unsigned char t;
159
160 spin_lock(&sch311x_wdt_data.io_lock);
161
162 /* stop the watchdog */
163 t = inb(sch311x_wdt_data.runtime_reg + GP60);
164 outb((t & ~0x0d) | 0x01, sch311x_wdt_data.runtime_reg + GP60);
165 /* disable timeout by setting it to 0 */
166 sch311x_wdt_set_timeout(0);
167
168 spin_unlock(&sch311x_wdt_data.io_lock);
169}
170
171static void sch311x_wdt_keepalive(void)
172{
173 spin_lock(&sch311x_wdt_data.io_lock);
174 sch311x_wdt_set_timeout(timeout);
175 spin_unlock(&sch311x_wdt_data.io_lock);
176}
177
178static int sch311x_wdt_set_heartbeat(int t)
179{
180 if (t < 1 || t > (255*60))
181 return -EINVAL;
182
183 /* When new timeout is bigger then 255 seconds,
184 * we will round up to minutes (with a max of 255) */
185 if (t > 255)
186 t = (((t - 1) / 60) + 1) * 60;
187
188 timeout = t;
189 return 0;
190}
191
192static void sch311x_wdt_get_status(int *status)
193{
194 unsigned char new_status;
195
196 *status = 0;
197
198 spin_lock(&sch311x_wdt_data.io_lock);
199
200 /* -- Watchdog timer control --
201 * Bit 0 Status Bit: 0 = Timer counting, 1 = Timeout occurred
202 * Bit 1 Reserved
203 * Bit 2 Force Timeout: 1 = Forces WD timeout event (self-cleaning)
204 * Bit 3 P20 Force Timeout enabled:
205 * 0 = P20 activity does not generate the WD timeout event
206 * 1 = P20 Allows rising edge of P20, from the keyboard
207 * controller, to force the WD timeout event.
208 * Bit 4-7 Reserved
209 */
210 new_status = inb(sch311x_wdt_data.runtime_reg + WDT_CTRL);
211 if (new_status & 0x01)
212 *status |= WDIOF_CARDRESET;
213
214 spin_unlock(&sch311x_wdt_data.io_lock);
215}
216
217/*
218 * /dev/watchdog handling
219 */
220
221static ssize_t sch311x_wdt_write(struct file *file, const char __user *buf,
222 size_t count, loff_t *ppos)
223{
224 if (count) {
225 if (!nowayout) {
226 size_t i;
227
228 sch311x_wdt_expect_close = 0;
229
230 for (i = 0; i != count; i++) {
231 char c;
232 if (get_user(c, buf + i))
233 return -EFAULT;
234 if (c == 'V')
235 sch311x_wdt_expect_close = 42;
236 }
237 }
238 sch311x_wdt_keepalive();
239 }
240 return count;
241}
242
243static long sch311x_wdt_ioctl(struct file *file, unsigned int cmd,
244 unsigned long arg)
245{
246 int status;
247 int new_timeout;
248 void __user *argp = (void __user *)arg;
249 int __user *p = argp;
250 static const struct watchdog_info ident = {
251 .options = WDIOF_KEEPALIVEPING |
252 WDIOF_SETTIMEOUT |
253 WDIOF_MAGICCLOSE,
254 .firmware_version = 1,
255 .identity = DRV_NAME,
256 };
257
258 switch (cmd) {
259 case WDIOC_GETSUPPORT:
260 if (copy_to_user(argp, &ident, sizeof(ident)))
261 return -EFAULT;
262 break;
263
264 case WDIOC_GETSTATUS:
265 {
266 sch311x_wdt_get_status(&status);
267 return put_user(status, p);
268 }
269 case WDIOC_GETBOOTSTATUS:
270 return put_user(sch311x_wdt_data.boot_status, p);
271
272 case WDIOC_SETOPTIONS:
273 {
274 int options, retval = -EINVAL;
275
276 if (get_user(options, p))
277 return -EFAULT;
278 if (options & WDIOS_DISABLECARD) {
279 sch311x_wdt_stop();
280 retval = 0;
281 }
282 if (options & WDIOS_ENABLECARD) {
283 sch311x_wdt_start();
284 retval = 0;
285 }
286 return retval;
287 }
288 case WDIOC_KEEPALIVE:
289 sch311x_wdt_keepalive();
290 break;
291
292 case WDIOC_SETTIMEOUT:
293 if (get_user(new_timeout, p))
294 return -EFAULT;
295 if (sch311x_wdt_set_heartbeat(new_timeout))
296 return -EINVAL;
297 sch311x_wdt_keepalive();
298 fallthrough;
299 case WDIOC_GETTIMEOUT:
300 return put_user(timeout, p);
301 default:
302 return -ENOTTY;
303 }
304 return 0;
305}
306
307static int sch311x_wdt_open(struct inode *inode, struct file *file)
308{
309 if (test_and_set_bit(0, &sch311x_wdt_is_open))
310 return -EBUSY;
311 /*
312 * Activate
313 */
314 sch311x_wdt_start();
315 return stream_open(inode, file);
316}
317
318static int sch311x_wdt_close(struct inode *inode, struct file *file)
319{
320 if (sch311x_wdt_expect_close == 42) {
321 sch311x_wdt_stop();
322 } else {
323 pr_crit("Unexpected close, not stopping watchdog!\n");
324 sch311x_wdt_keepalive();
325 }
326 clear_bit(0, &sch311x_wdt_is_open);
327 sch311x_wdt_expect_close = 0;
328 return 0;
329}
330
331/*
332 * Kernel Interfaces
333 */
334
335static const struct file_operations sch311x_wdt_fops = {
336 .owner = THIS_MODULE,
337 .llseek = no_llseek,
338 .write = sch311x_wdt_write,
339 .unlocked_ioctl = sch311x_wdt_ioctl,
340 .compat_ioctl = compat_ptr_ioctl,
341 .open = sch311x_wdt_open,
342 .release = sch311x_wdt_close,
343};
344
345static struct miscdevice sch311x_wdt_miscdev = {
346 .minor = WATCHDOG_MINOR,
347 .name = "watchdog",
348 .fops = &sch311x_wdt_fops,
349};
350
351/*
352 * Init & exit routines
353 */
354
355static int sch311x_wdt_probe(struct platform_device *pdev)
356{
357 struct device *dev = &pdev->dev;
358 int err;
359
360 spin_lock_init(&sch311x_wdt_data.io_lock);
361
362 if (!request_region(sch311x_wdt_data.runtime_reg + GP60, 1, DRV_NAME)) {
363 dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n",
364 sch311x_wdt_data.runtime_reg + GP60,
365 sch311x_wdt_data.runtime_reg + GP60);
366 err = -EBUSY;
367 goto exit;
368 }
369
370 if (!request_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4,
371 DRV_NAME)) {
372 dev_err(dev, "Failed to request region 0x%04x-0x%04x.\n",
373 sch311x_wdt_data.runtime_reg + WDT_TIME_OUT,
374 sch311x_wdt_data.runtime_reg + WDT_CTRL);
375 err = -EBUSY;
376 goto exit_release_region;
377 }
378
379 /* Make sure that the watchdog is not running */
380 sch311x_wdt_stop();
381
382 /* Disable keyboard and mouse interaction and interrupt */
383 /* -- Watchdog timer configuration --
384 * Bit 0 Reserved
385 * Bit 1 Keyboard enable: 0* = No Reset, 1 = Reset WDT upon KBD Intr.
386 * Bit 2 Mouse enable: 0* = No Reset, 1 = Reset WDT upon Mouse Intr
387 * Bit 3 Reserved
388 * Bit 4-7 WDT Interrupt Mapping: (0000* = Disabled,
389 * 0001=IRQ1, 0010=(Invalid), 0011=IRQ3 to 1111=IRQ15)
390 */
391 outb(0, sch311x_wdt_data.runtime_reg + WDT_CFG);
392
393 /* Check that the heartbeat value is within it's range ;
394 * if not reset to the default */
395 if (sch311x_wdt_set_heartbeat(timeout)) {
396 sch311x_wdt_set_heartbeat(WATCHDOG_TIMEOUT);
397 dev_info(dev, "timeout value must be 1<=x<=15300, using %d\n",
398 timeout);
399 }
400
401 /* Get status at boot */
402 sch311x_wdt_get_status(&sch311x_wdt_data.boot_status);
403
404 sch311x_wdt_miscdev.parent = dev;
405
406 err = misc_register(&sch311x_wdt_miscdev);
407 if (err != 0) {
408 dev_err(dev, "cannot register miscdev on minor=%d (err=%d)\n",
409 WATCHDOG_MINOR, err);
410 goto exit_release_region2;
411 }
412
413 dev_info(dev,
414 "SMSC SCH311x WDT initialized. timeout=%d sec (nowayout=%d)\n",
415 timeout, nowayout);
416
417 return 0;
418
419exit_release_region2:
420 release_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4);
421exit_release_region:
422 release_region(sch311x_wdt_data.runtime_reg + GP60, 1);
423 sch311x_wdt_data.runtime_reg = 0;
424exit:
425 return err;
426}
427
428static int sch311x_wdt_remove(struct platform_device *pdev)
429{
430 /* Stop the timer before we leave */
431 if (!nowayout)
432 sch311x_wdt_stop();
433
434 /* Deregister */
435 misc_deregister(&sch311x_wdt_miscdev);
436 release_region(sch311x_wdt_data.runtime_reg + WDT_TIME_OUT, 4);
437 release_region(sch311x_wdt_data.runtime_reg + GP60, 1);
438 sch311x_wdt_data.runtime_reg = 0;
439 return 0;
440}
441
442static void sch311x_wdt_shutdown(struct platform_device *dev)
443{
444 /* Turn the WDT off if we have a soft shutdown */
445 sch311x_wdt_stop();
446}
447
448static struct platform_driver sch311x_wdt_driver = {
449 .probe = sch311x_wdt_probe,
450 .remove = sch311x_wdt_remove,
451 .shutdown = sch311x_wdt_shutdown,
452 .driver = {
453 .name = DRV_NAME,
454 },
455};
456
457static int __init sch311x_detect(int sio_config_port, unsigned short *addr)
458{
459 int err = 0, reg;
460 unsigned short base_addr;
461 unsigned char dev_id;
462
463 sch311x_sio_enter(sio_config_port);
464
465 /* Check device ID. We currently know about:
466 * SCH3112 (0x7c), SCH3114 (0x7d), and SCH3116 (0x7f). */
467 reg = force_id ? force_id : sch311x_sio_inb(sio_config_port, 0x20);
468 if (!(reg == 0x7c || reg == 0x7d || reg == 0x7f)) {
469 err = -ENODEV;
470 goto exit;
471 }
472 dev_id = reg == 0x7c ? 2 : reg == 0x7d ? 4 : 6;
473
474 /* Select logical device A (runtime registers) */
475 sch311x_sio_outb(sio_config_port, 0x07, 0x0a);
476
477 /* Check if Logical Device Register is currently active */
478 if ((sch311x_sio_inb(sio_config_port, 0x30) & 0x01) == 0)
479 pr_info("Seems that LDN 0x0a is not active...\n");
480
481 /* Get the base address of the runtime registers */
482 base_addr = (sch311x_sio_inb(sio_config_port, 0x60) << 8) |
483 sch311x_sio_inb(sio_config_port, 0x61);
484 if (!base_addr) {
485 pr_err("Base address not set\n");
486 err = -ENODEV;
487 goto exit;
488 }
489 *addr = base_addr;
490
491 pr_info("Found an SMSC SCH311%d chip at 0x%04x\n", dev_id, base_addr);
492
493exit:
494 sch311x_sio_exit(sio_config_port);
495 return err;
496}
497
498static int __init sch311x_wdt_init(void)
499{
500 int err, i, found = 0;
501 unsigned short addr = 0;
502
503 for (i = 0; !found && sch311x_ioports[i]; i++)
504 if (sch311x_detect(sch311x_ioports[i], &addr) == 0)
505 found++;
506
507 if (!found)
508 return -ENODEV;
509
510 sch311x_wdt_data.runtime_reg = addr;
511
512 err = platform_driver_register(&sch311x_wdt_driver);
513 if (err)
514 return err;
515
516 sch311x_wdt_pdev = platform_device_register_simple(DRV_NAME, addr,
517 NULL, 0);
518
519 if (IS_ERR(sch311x_wdt_pdev)) {
520 err = PTR_ERR(sch311x_wdt_pdev);
521 goto unreg_platform_driver;
522 }
523
524 return 0;
525
526unreg_platform_driver:
527 platform_driver_unregister(&sch311x_wdt_driver);
528 return err;
529}
530
531static void __exit sch311x_wdt_exit(void)
532{
533 platform_device_unregister(sch311x_wdt_pdev);
534 platform_driver_unregister(&sch311x_wdt_driver);
535}
536
537module_init(sch311x_wdt_init);
538module_exit(sch311x_wdt_exit);
539
540MODULE_AUTHOR("Wim Van Sebroeck <wim@iguana.be>");
541MODULE_DESCRIPTION("SMSC SCH311x WatchDog Timer Driver");
542MODULE_LICENSE("GPL");