1 /***************************************************************************
2 * Copyright (C) 2006 by Hans Edgington <hans@edgington.nl> *
3 * Copyright (C) 2007-2009 Hans de Goede <hdegoede@redhat.com> *
4 * Copyright (C) 2010 Giel van Schijndel <me@mortis.eu> *
6 * This program is free software; you can redistribute it and/or modify *
7 * it under the terms of the GNU General Public License as published by *
8 * the Free Software Foundation; either version 2 of the License, or *
9 * (at your option) any later version. *
11 * This program is distributed in the hope that it will be useful, *
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of *
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
14 * GNU General Public License for more details. *
16 * You should have received a copy of the GNU General Public License *
17 * along with this program; if not, write to the *
18 * Free Software Foundation, Inc., *
19 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
20 ***************************************************************************/
22 #include <linux/err.h>
24 #include <linux/init.h>
26 #include <linux/ioport.h>
27 #include <linux/miscdevice.h>
28 #include <linux/module.h>
29 #include <linux/mutex.h>
30 #include <linux/notifier.h>
31 #include <linux/reboot.h>
32 #include <linux/uaccess.h>
33 #include <linux/watchdog.h>
35 #define DRVNAME "f71808e_wdt"
37 #define SIO_F71808FG_LD_WDT 0x07 /* Watchdog timer logical device */
38 #define SIO_UNLOCK_KEY 0x87 /* Key to enable Super-I/O */
39 #define SIO_LOCK_KEY 0xAA /* Key to diasble Super-I/O */
41 #define SIO_REG_LDSEL 0x07 /* Logical device select */
42 #define SIO_REG_DEVID 0x20 /* Device ID (2 bytes) */
43 #define SIO_REG_DEVREV 0x22 /* Device revision */
44 #define SIO_REG_MANID 0x23 /* Fintek ID (2 bytes) */
45 #define SIO_REG_MFUNCT1 0x29 /* Multi function select 1 */
46 #define SIO_REG_MFUNCT2 0x2a /* Multi function select 2 */
47 #define SIO_REG_MFUNCT3 0x2b /* Multi function select 3 */
48 #define SIO_REG_ENABLE 0x30 /* Logical device enable */
49 #define SIO_REG_ADDR 0x60 /* Logical device address (2 bytes) */
51 #define SIO_FINTEK_ID 0x1934 /* Manufacturers ID */
52 #define SIO_F71808_ID 0x0901 /* Chipset ID */
53 #define SIO_F71858_ID 0x0507 /* Chipset ID */
54 #define SIO_F71862_ID 0x0601 /* Chipset ID */
55 #define SIO_F71882_ID 0x0541 /* Chipset ID */
56 #define SIO_F71889_ID 0x0723 /* Chipset ID */
58 #define F71808FG_REG_WDO_CONF 0xf0
59 #define F71808FG_REG_WDT_CONF 0xf5
60 #define F71808FG_REG_WD_TIME 0xf6
62 #define F71808FG_FLAG_WDOUT_EN 7
64 #define F71808FG_FLAG_WDTMOUT_STS 5
65 #define F71808FG_FLAG_WD_EN 5
66 #define F71808FG_FLAG_WD_PULSE 4
67 #define F71808FG_FLAG_WD_UNIT 3
70 #define WATCHDOG_TIMEOUT 60 /* 1 minute default timeout */
71 #define WATCHDOG_MAX_TIMEOUT (60 * 255)
72 #define WATCHDOG_PULSE_WIDTH 125 /* 125 ms, default pulse width for
75 static unsigned short force_id;
76 module_param(force_id, ushort, 0);
77 MODULE_PARM_DESC(force_id, "Override the detected device ID");
79 static const int max_timeout = WATCHDOG_MAX_TIMEOUT;
80 static int timeout = WATCHDOG_TIMEOUT; /* default timeout in seconds */
81 module_param(timeout, int, 0);
82 MODULE_PARM_DESC(timeout,
83 "Watchdog timeout in seconds. 1<= timeout <="
84 __MODULE_STRING(WATCHDOG_MAX_TIMEOUT) " (default="
85 __MODULE_STRING(WATCHDOG_TIMEOUT) ")");
87 static unsigned int pulse_width = WATCHDOG_PULSE_WIDTH;
88 module_param(pulse_width, uint, 0);
89 MODULE_PARM_DESC(pulse_width,
90 "Watchdog signal pulse width. 0(=level), 1 ms, 25 ms, 125 ms or 5000 ms"
91 " (default=" __MODULE_STRING(WATCHDOG_PULSE_WIDTH) ")");
93 static int nowayout = WATCHDOG_NOWAYOUT;
94 module_param(nowayout, bool, 0444);
95 MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close");
97 static unsigned int start_withtimeout;
98 module_param(start_withtimeout, uint, 0);
99 MODULE_PARM_DESC(start_withtimeout, "Start watchdog timer on module load with"
100 " given initial timeout. Zero (default) disables this feature.");
102 enum chips { f71808fg, f71858fg, f71862fg, f71882fg, f71889fg };
104 static const char *f71808e_names[] = {
112 /* Super-I/O Function prototypes */
113 static inline int superio_inb(int base, int reg);
114 static inline int superio_inw(int base, int reg);
115 static inline void superio_outb(int base, int reg, u8 val);
116 static inline void superio_set_bit(int base, int reg, int bit);
117 static inline void superio_clear_bit(int base, int reg, int bit);
118 static inline int superio_enter(int base);
119 static inline void superio_select(int base, int ld);
120 static inline void superio_exit(int base);
122 struct watchdog_data {
123 unsigned short sioaddr;
125 unsigned long opened;
128 struct watchdog_info ident;
130 unsigned short timeout;
131 u8 timer_val; /* content for the wd_time register */
133 u8 pulse_val; /* pulse width flag */
134 char pulse_mode; /* enable pulse output mode? */
135 char caused_reboot; /* last reboot was by the watchdog */
138 static struct watchdog_data watchdog = {
139 .lock = __MUTEX_INITIALIZER(watchdog.lock),
142 /* Super I/O functions */
143 static inline int superio_inb(int base, int reg)
146 return inb(base + 1);
149 static int superio_inw(int base, int reg)
152 val = superio_inb(base, reg) << 8;
153 val |= superio_inb(base, reg + 1);
157 static inline void superio_outb(int base, int reg, u8 val)
163 static inline void superio_set_bit(int base, int reg, int bit)
165 unsigned long val = superio_inb(base, reg);
166 __set_bit(bit, &val);
167 superio_outb(base, reg, val);
170 static inline void superio_clear_bit(int base, int reg, int bit)
172 unsigned long val = superio_inb(base, reg);
173 __clear_bit(bit, &val);
174 superio_outb(base, reg, val);
177 static inline int superio_enter(int base)
179 /* Don't step on other drivers' I/O space by accident */
180 if (!request_muxed_region(base, 2, DRVNAME)) {
181 printk(KERN_ERR DRVNAME ": I/O address 0x%04x already in use\n",
186 /* according to the datasheet the key must be send twice! */
187 outb(SIO_UNLOCK_KEY, base);
188 outb(SIO_UNLOCK_KEY, base);
193 static inline void superio_select(int base, int ld)
195 outb(SIO_REG_LDSEL, base);
199 static inline void superio_exit(int base)
201 outb(SIO_LOCK_KEY, base);
202 release_region(base, 2);
205 static int watchdog_set_timeout(int timeout)
208 || timeout > max_timeout) {
209 printk(KERN_ERR DRVNAME ": watchdog timeout out of range\n");
213 mutex_lock(&watchdog.lock);
215 watchdog.timeout = timeout;
216 if (timeout > 0xff) {
217 watchdog.timer_val = DIV_ROUND_UP(timeout, 60);
218 watchdog.minutes_mode = true;
220 watchdog.timer_val = timeout;
221 watchdog.minutes_mode = false;
224 mutex_unlock(&watchdog.lock);
229 static int watchdog_set_pulse_width(unsigned int pw)
233 mutex_lock(&watchdog.lock);
236 watchdog.pulse_val = 0;
237 } else if (pw <= 25) {
238 watchdog.pulse_val = 1;
239 } else if (pw <= 125) {
240 watchdog.pulse_val = 2;
241 } else if (pw <= 5000) {
242 watchdog.pulse_val = 3;
244 printk(KERN_ERR DRVNAME ": pulse width out of range\n");
249 watchdog.pulse_mode = pw;
252 mutex_unlock(&watchdog.lock);
256 static int watchdog_keepalive(void)
260 mutex_lock(&watchdog.lock);
261 err = superio_enter(watchdog.sioaddr);
264 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
266 if (watchdog.minutes_mode)
267 /* select minutes for timer units */
268 superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
269 F71808FG_FLAG_WD_UNIT);
271 /* select seconds for timer units */
272 superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
273 F71808FG_FLAG_WD_UNIT);
275 /* Set timer value */
276 superio_outb(watchdog.sioaddr, F71808FG_REG_WD_TIME,
279 superio_exit(watchdog.sioaddr);
282 mutex_unlock(&watchdog.lock);
286 static int watchdog_start(void)
288 /* Make sure we don't die as soon as the watchdog is enabled below */
289 int err = watchdog_keepalive();
293 mutex_lock(&watchdog.lock);
294 err = superio_enter(watchdog.sioaddr);
297 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
299 /* Watchdog pin configuration */
300 switch (watchdog.type) {
302 /* Set pin 21 to GPIO23/WDTRST#, then to WDTRST# */
303 superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT2, 3);
304 superio_clear_bit(watchdog.sioaddr, SIO_REG_MFUNCT3, 3);
308 /* Set pin 56 to WDTRST# */
309 superio_set_bit(watchdog.sioaddr, SIO_REG_MFUNCT1, 1);
313 /* set pin 40 to WDTRST# */
314 superio_outb(watchdog.sioaddr, SIO_REG_MFUNCT3,
315 superio_inb(watchdog.sioaddr, SIO_REG_MFUNCT3) & 0xcf);
320 * 'default' label to shut up the compiler and catch
327 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
328 superio_set_bit(watchdog.sioaddr, SIO_REG_ENABLE, 0);
329 superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDO_CONF,
330 F71808FG_FLAG_WDOUT_EN);
332 superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
333 F71808FG_FLAG_WD_EN);
335 if (watchdog.pulse_mode) {
336 /* Select "pulse" output mode with given duration */
337 u8 wdt_conf = superio_inb(watchdog.sioaddr,
338 F71808FG_REG_WDT_CONF);
340 /* Set WD_PSWIDTH bits (1:0) */
341 wdt_conf = (wdt_conf & 0xfc) | (watchdog.pulse_val & 0x03);
342 /* Set WD_PULSE to "pulse" mode */
343 wdt_conf |= BIT(F71808FG_FLAG_WD_PULSE);
345 superio_outb(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
348 /* Select "level" output mode */
349 superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
350 F71808FG_FLAG_WD_PULSE);
354 superio_exit(watchdog.sioaddr);
356 mutex_unlock(&watchdog.lock);
361 static int watchdog_stop(void)
365 mutex_lock(&watchdog.lock);
366 err = superio_enter(watchdog.sioaddr);
369 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
371 superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF,
372 F71808FG_FLAG_WD_EN);
374 superio_exit(watchdog.sioaddr);
377 mutex_unlock(&watchdog.lock);
382 static int watchdog_get_status(void)
386 mutex_lock(&watchdog.lock);
387 status = (watchdog.caused_reboot) ? WDIOF_CARDRESET : 0;
388 mutex_unlock(&watchdog.lock);
393 static bool watchdog_is_running(void)
396 * if we fail to determine the watchdog's status assume it to be
397 * running to be on the safe side
399 bool is_running = true;
401 mutex_lock(&watchdog.lock);
402 if (superio_enter(watchdog.sioaddr))
404 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
406 is_running = (superio_inb(watchdog.sioaddr, SIO_REG_ENABLE) & BIT(0))
407 && (superio_inb(watchdog.sioaddr, F71808FG_REG_WDT_CONF)
408 & F71808FG_FLAG_WD_EN);
410 superio_exit(watchdog.sioaddr);
413 mutex_unlock(&watchdog.lock);
417 /* /dev/watchdog api */
419 static int watchdog_open(struct inode *inode, struct file *file)
423 /* If the watchdog is alive we don't need to start it again */
424 if (test_and_set_bit(0, &watchdog.opened))
427 err = watchdog_start();
429 clear_bit(0, &watchdog.opened);
434 __module_get(THIS_MODULE);
436 watchdog.expect_close = 0;
437 return nonseekable_open(inode, file);
440 static int watchdog_release(struct inode *inode, struct file *file)
442 clear_bit(0, &watchdog.opened);
444 if (!watchdog.expect_close) {
445 watchdog_keepalive();
446 printk(KERN_CRIT DRVNAME
447 ": Unexpected close, not stopping watchdog!\n");
448 } else if (!nowayout) {
456 * @file: file handle to the watchdog
457 * @buf: buffer to write
458 * @count: count of bytes
459 * @ppos: pointer to the position to write. No seeks allowed
461 * A write to a watchdog device is defined as a keepalive signal. Any
462 * write of data will do, as we we don't define content meaning.
465 static ssize_t watchdog_write(struct file *file, const char __user *buf,
466 size_t count, loff_t *ppos)
472 /* In case it was set long ago */
473 bool expect_close = false;
475 for (i = 0; i != count; i++) {
477 if (get_user(c, buf + i))
479 expect_close = (c == 'V');
482 /* Properly order writes across fork()ed processes */
483 mutex_lock(&watchdog.lock);
484 watchdog.expect_close = expect_close;
485 mutex_unlock(&watchdog.lock);
488 /* someone wrote to us, we should restart timer */
489 watchdog_keepalive();
496 * @inode: inode of the device
497 * @file: file handle to the device
498 * @cmd: watchdog command
499 * @arg: argument pointer
501 * The watchdog API defines a common set of functions for all watchdogs
502 * according to their available features.
504 static long watchdog_ioctl(struct file *file, unsigned int cmd,
511 struct watchdog_info __user *ident;
515 uarg.i = (int __user *)arg;
518 case WDIOC_GETSUPPORT:
519 return copy_to_user(uarg.ident, &watchdog.ident,
520 sizeof(watchdog.ident)) ? -EFAULT : 0;
522 case WDIOC_GETSTATUS:
523 status = watchdog_get_status();
526 return put_user(status, uarg.i);
528 case WDIOC_GETBOOTSTATUS:
529 return put_user(0, uarg.i);
531 case WDIOC_SETOPTIONS:
532 if (get_user(new_options, uarg.i))
535 if (new_options & WDIOS_DISABLECARD)
538 if (new_options & WDIOS_ENABLECARD)
539 return watchdog_start();
542 case WDIOC_KEEPALIVE:
543 watchdog_keepalive();
546 case WDIOC_SETTIMEOUT:
547 if (get_user(new_timeout, uarg.i))
550 if (watchdog_set_timeout(new_timeout))
553 watchdog_keepalive();
556 case WDIOC_GETTIMEOUT:
557 return put_user(watchdog.timeout, uarg.i);
565 static int watchdog_notify_sys(struct notifier_block *this, unsigned long code,
568 if (code == SYS_DOWN || code == SYS_HALT)
573 static const struct file_operations watchdog_fops = {
574 .owner = THIS_MODULE,
576 .open = watchdog_open,
577 .release = watchdog_release,
578 .write = watchdog_write,
579 .unlocked_ioctl = watchdog_ioctl,
582 static struct miscdevice watchdog_miscdev = {
583 .minor = WATCHDOG_MINOR,
585 .fops = &watchdog_fops,
588 static struct notifier_block watchdog_notifier = {
589 .notifier_call = watchdog_notify_sys,
592 static int __init watchdog_init(int sioaddr)
594 int wdt_conf, err = 0;
596 /* No need to lock watchdog.lock here because no entry points
597 * into the module have been registered yet.
599 watchdog.sioaddr = sioaddr;
600 watchdog.ident.options = WDIOC_SETTIMEOUT
602 | WDIOF_KEEPALIVEPING;
604 snprintf(watchdog.ident.identity,
605 sizeof(watchdog.ident.identity), "%s watchdog",
606 f71808e_names[watchdog.type]);
608 err = superio_enter(sioaddr);
611 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
613 wdt_conf = superio_inb(sioaddr, F71808FG_REG_WDT_CONF);
614 watchdog.caused_reboot = wdt_conf & F71808FG_FLAG_WDTMOUT_STS;
616 superio_exit(sioaddr);
618 err = watchdog_set_timeout(timeout);
621 err = watchdog_set_pulse_width(pulse_width);
625 err = register_reboot_notifier(&watchdog_notifier);
629 err = misc_register(&watchdog_miscdev);
631 printk(KERN_ERR DRVNAME
632 ": cannot register miscdev on minor=%d\n",
633 watchdog_miscdev.minor);
637 if (start_withtimeout) {
638 if (start_withtimeout <= 0
639 || start_withtimeout > max_timeout) {
640 printk(KERN_ERR DRVNAME
641 ": starting timeout out of range\n");
646 err = watchdog_start();
648 printk(KERN_ERR DRVNAME
649 ": cannot start watchdog timer\n");
653 mutex_lock(&watchdog.lock);
654 err = superio_enter(sioaddr);
657 superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT);
659 if (start_withtimeout > 0xff) {
660 /* select minutes for timer units */
661 superio_set_bit(sioaddr, F71808FG_REG_WDT_CONF,
662 F71808FG_FLAG_WD_UNIT);
663 superio_outb(sioaddr, F71808FG_REG_WD_TIME,
664 DIV_ROUND_UP(start_withtimeout, 60));
666 /* select seconds for timer units */
667 superio_clear_bit(sioaddr, F71808FG_REG_WDT_CONF,
668 F71808FG_FLAG_WD_UNIT);
669 superio_outb(sioaddr, F71808FG_REG_WD_TIME,
673 superio_exit(sioaddr);
674 mutex_unlock(&watchdog.lock);
677 __module_get(THIS_MODULE);
679 printk(KERN_INFO DRVNAME
680 ": watchdog started with initial timeout of %u sec\n",
687 mutex_unlock(&watchdog.lock);
689 misc_deregister(&watchdog_miscdev);
691 unregister_reboot_notifier(&watchdog_notifier);
696 static int __init f71808e_find(int sioaddr)
699 int err = superio_enter(sioaddr);
703 devid = superio_inw(sioaddr, SIO_REG_MANID);
704 if (devid != SIO_FINTEK_ID) {
705 pr_debug(DRVNAME ": Not a Fintek device\n");
710 devid = force_id ? force_id : superio_inw(sioaddr, SIO_REG_DEVID);
713 watchdog.type = f71808fg;
716 watchdog.type = f71882fg;
719 watchdog.type = f71889fg;
722 /* These have a watchdog, though it isn't implemented (yet). */
726 /* Confirmed (by datasheet) not to have a watchdog. */
730 printk(KERN_INFO DRVNAME ": Unrecognized Fintek device: %04x\n",
731 (unsigned int)devid);
736 printk(KERN_INFO DRVNAME ": Found %s watchdog chip, revision %d\n",
737 f71808e_names[watchdog.type],
738 (int)superio_inb(sioaddr, SIO_REG_DEVREV));
740 superio_exit(sioaddr);
744 static int __init f71808e_init(void)
746 static const unsigned short addrs[] = { 0x2e, 0x4e };
750 for (i = 0; i < ARRAY_SIZE(addrs); i++) {
751 err = f71808e_find(addrs[i]);
755 if (i == ARRAY_SIZE(addrs))
758 return watchdog_init(addrs[i]);
761 static void __exit f71808e_exit(void)
763 if (watchdog_is_running()) {
764 printk(KERN_WARNING DRVNAME
765 ": Watchdog timer still running, stopping it\n");
768 misc_deregister(&watchdog_miscdev);
769 unregister_reboot_notifier(&watchdog_notifier);
772 MODULE_DESCRIPTION("F71808E Watchdog Driver");
773 MODULE_AUTHOR("Giel van Schijndel <me@mortis.eu>");
774 MODULE_LICENSE("GPL");
776 module_init(f71808e_init);
777 module_exit(f71808e_exit);