2 * w83627hf/thf WDT driver
4 * (c) Copyright 2013 Guenter Roeck
5 * converted to watchdog infrastructure
7 * (c) Copyright 2007 Vlad Drukker <vlad@storewiz.com>
8 * added support for W83627THF.
10 * (c) Copyright 2003,2007 Pádraig Brady <P@draigBrady.com>
12 * Based on advantechwdt.c which is based on wdt.c.
13 * Original copyright messages:
15 * (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl>
17 * (c) Copyright 1996 Alan Cox <alan@lxorguk.ukuu.org.uk>,
18 * All Rights Reserved.
20 * This program is free software; you can redistribute it and/or
21 * modify it under the terms of the GNU General Public License
22 * as published by the Free Software Foundation; either version
23 * 2 of the License, or (at your option) any later version.
25 * Neither Alan Cox nor CymruNet Ltd. admit liability nor provide
26 * warranty for any of this software. This material is provided
27 * "AS-IS" and at no charge.
29 * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk>
32 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
34 #include <linux/module.h>
35 #include <linux/moduleparam.h>
36 #include <linux/types.h>
37 #include <linux/watchdog.h>
38 #include <linux/ioport.h>
39 #include <linux/notifier.h>
40 #include <linux/reboot.h>
41 #include <linux/init.h>
44 #define WATCHDOG_NAME "w83627hf/thf/hg/dhg WDT"
45 #define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */
47 /* You must set this - there is no sane way to probe for this board. */
48 static int wdt_io = 0x2E;
49 module_param(wdt_io, int, 0);
50 MODULE_PARM_DESC(wdt_io, "w83627hf/thf WDT io port (default 0x2E)");
52 static int timeout; /* in seconds */
53 module_param(timeout, int, 0);
54 MODULE_PARM_DESC(timeout,
55 "Watchdog timeout in seconds. 1 <= timeout <= 255, default="
56 __MODULE_STRING(WATCHDOG_TIMEOUT) ".");
58 static bool nowayout = WATCHDOG_NOWAYOUT;
59 module_param(nowayout, bool, 0);
60 MODULE_PARM_DESC(nowayout,
61 "Watchdog cannot be stopped once started (default="
62 __MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
68 #define WDT_EFER (wdt_io+0) /* Extended Function Enable Registers */
69 #define WDT_EFIR (wdt_io+0) /* Extended Function Index Register
71 #define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */
73 static void w83627hf_select_wd_register(void)
75 outb_p(0x87, WDT_EFER); /* Enter extended function mode */
76 outb_p(0x87, WDT_EFER); /* Again according to manual */
77 outb_p(0x07, WDT_EFER); /* point to logical device number reg */
78 outb_p(0x08, WDT_EFDR); /* select logical device 8 (GPIO2) */
81 static void w83627hf_unselect_wd_register(void)
83 outb_p(0xAA, WDT_EFER); /* Leave extended function mode */
86 /* tyan motherboards seem to set F5 to 0x4C ?
87 * So explicitly init to appropriate value. */
89 static void w83627hf_init(struct watchdog_device *wdog)
93 w83627hf_select_wd_register();
95 outb(0x20, WDT_EFER); /* check chip version */
97 if (t == 0x82) { /* W83627THF */
98 outb_p(0x2b, WDT_EFER); /* select GPIO3 */
99 t = ((inb_p(WDT_EFDR) & 0xf7) | 0x04); /* select WDT0 */
100 outb_p(0x2b, WDT_EFER);
101 outb_p(t, WDT_EFDR); /* set GPIO3 to WDT0 */
102 } else if (t == 0x88 || t == 0xa0) { /* W83627EHF / W83627DHG */
103 outb_p(0x2d, WDT_EFER); /* select GPIO5 */
104 t = inb_p(WDT_EFDR) & ~0x01; /* PIN77 -> WDT0# */
105 outb_p(0x2d, WDT_EFER);
106 outb_p(t, WDT_EFDR); /* set GPIO5 to WDT0 */
109 outb_p(0x30, WDT_EFER); /* select CR30 */
110 outb_p(0x01, WDT_EFDR); /* set bit 0 to activate GPIO2 */
112 outb_p(0xF6, WDT_EFER); /* Select CRF6 */
113 t = inb_p(WDT_EFDR); /* read CRF6 */
115 pr_info("Watchdog already running. Resetting timeout to %d sec\n",
117 outb_p(wdog->timeout, WDT_EFDR); /* Write back to CRF6 */
120 outb_p(0xF5, WDT_EFER); /* Select CRF5 */
121 t = inb_p(WDT_EFDR); /* read CRF5 */
122 t &= ~0x0C; /* set second mode & disable keyboard
123 turning off watchdog */
124 t |= 0x02; /* enable the WDTO# output low pulse
125 to the KBRST# pin (PIN60) */
126 outb_p(t, WDT_EFDR); /* Write back to CRF5 */
128 outb_p(0xF7, WDT_EFER); /* Select CRF7 */
129 t = inb_p(WDT_EFDR); /* read CRF7 */
130 t &= ~0xC0; /* disable keyboard & mouse turning off
132 outb_p(t, WDT_EFDR); /* Write back to CRF7 */
134 w83627hf_unselect_wd_register();
137 static int wdt_set_time(unsigned int timeout)
139 w83627hf_select_wd_register();
141 outb_p(0xF6, WDT_EFER); /* Select CRF6 */
142 outb_p(timeout, WDT_EFDR); /* Write Timeout counter to CRF6 */
144 w83627hf_unselect_wd_register();
149 static int wdt_start(struct watchdog_device *wdog)
151 return wdt_set_time(wdog->timeout);
154 static int wdt_stop(struct watchdog_device *wdog)
156 return wdt_set_time(0);
159 static int wdt_set_timeout(struct watchdog_device *wdog, unsigned int timeout)
161 wdog->timeout = timeout;
166 static unsigned int wdt_get_time(struct watchdog_device *wdog)
168 unsigned int timeleft;
170 w83627hf_select_wd_register();
172 outb_p(0xF6, WDT_EFER); /* Select CRF6 */
173 timeleft = inb_p(WDT_EFDR); /* Read Timeout counter to CRF6 */
175 w83627hf_unselect_wd_register();
181 * Notifier for system down
183 static int wdt_notify_sys(struct notifier_block *this, unsigned long code,
186 if (code == SYS_DOWN || code == SYS_HALT)
187 wdt_set_time(0); /* Turn the WDT off */
196 static struct watchdog_info wdt_info = {
197 .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE,
198 .identity = "W83627HF Watchdog",
201 static struct watchdog_ops wdt_ops = {
202 .owner = THIS_MODULE,
205 .set_timeout = wdt_set_timeout,
206 .get_timeleft = wdt_get_time,
209 static struct watchdog_device wdt_dev = {
212 .timeout = WATCHDOG_TIMEOUT,
218 * The WDT needs to learn about soft shutdowns in order to
219 * turn the timebomb registers off.
222 static struct notifier_block wdt_notifier = {
223 .notifier_call = wdt_notify_sys,
226 static int __init wdt_init(void)
230 pr_info("WDT driver for the Winbond(TM) W83627HF/THF/HG/DHG Super I/O chip initialising\n");
232 if (!request_region(wdt_io, 1, WATCHDOG_NAME)) {
233 pr_err("I/O address 0x%04x already in use\n", wdt_io);
237 watchdog_init_timeout(&wdt_dev, timeout, NULL);
238 watchdog_set_nowayout(&wdt_dev, nowayout);
240 w83627hf_init(&wdt_dev);
242 ret = register_reboot_notifier(&wdt_notifier);
244 pr_err("cannot register reboot notifier (err=%d)\n", ret);
248 ret = watchdog_register_device(&wdt_dev);
252 pr_info("initialized. timeout=%d sec (nowayout=%d)\n",
253 wdt_dev.timeout, nowayout);
258 unregister_reboot_notifier(&wdt_notifier);
260 release_region(wdt_io, 1);
264 static void __exit wdt_exit(void)
266 watchdog_unregister_device(&wdt_dev);
267 unregister_reboot_notifier(&wdt_notifier);
268 release_region(wdt_io, 1);
271 module_init(wdt_init);
272 module_exit(wdt_exit);
274 MODULE_LICENSE("GPL");
275 MODULE_AUTHOR("Pádraig Brady <P@draigBrady.com>");
276 MODULE_DESCRIPTION("w83627hf/thf WDT driver");