/* * w83627hf/thf WDT driver * * (c) Copyright 2013 Guenter Roeck * converted to watchdog infrastructure * * (c) Copyright 2007 Vlad Drukker * added support for W83627THF. * * (c) Copyright 2003,2007 Pádraig Brady * * Based on advantechwdt.c which is based on wdt.c. * Original copyright messages: * * (c) Copyright 2000-2001 Marek Michalkiewicz * * (c) Copyright 1996 Alan Cox , * All Rights Reserved. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * Neither Alan Cox nor CymruNet Ltd. admit liability nor provide * warranty for any of this software. This material is provided * "AS-IS" and at no charge. * * (c) Copyright 1995 Alan Cox */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #include #include #include #define WATCHDOG_NAME "w83627hf/thf/hg/dhg WDT" #define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */ /* You must set this - there is no sane way to probe for this board. */ static int wdt_io = 0x2E; module_param(wdt_io, int, 0); MODULE_PARM_DESC(wdt_io, "w83627hf/thf WDT io port (default 0x2E)"); static int timeout; /* in seconds */ module_param(timeout, int, 0); MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1 <= timeout <= 255, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) "."); static bool nowayout = WATCHDOG_NOWAYOUT; module_param(nowayout, bool, 0); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); /* * Kernel methods. */ #define WDT_EFER (wdt_io+0) /* Extended Function Enable Registers */ #define WDT_EFIR (wdt_io+0) /* Extended Function Index Register (same as EFER) */ #define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */ static void w83627hf_select_wd_register(void) { outb_p(0x87, WDT_EFER); /* Enter extended function mode */ outb_p(0x87, WDT_EFER); /* Again according to manual */ outb_p(0x07, WDT_EFER); /* point to logical device number reg */ outb_p(0x08, WDT_EFDR); /* select logical device 8 (GPIO2) */ } static void w83627hf_unselect_wd_register(void) { outb_p(0xAA, WDT_EFER); /* Leave extended function mode */ } /* tyan motherboards seem to set F5 to 0x4C ? * So explicitly init to appropriate value. */ static void w83627hf_init(struct watchdog_device *wdog) { unsigned char t; w83627hf_select_wd_register(); outb(0x20, WDT_EFER); /* check chip version */ t = inb(WDT_EFDR); if (t == 0x82) { /* W83627THF */ outb_p(0x2b, WDT_EFER); /* select GPIO3 */ t = ((inb_p(WDT_EFDR) & 0xf7) | 0x04); /* select WDT0 */ outb_p(0x2b, WDT_EFER); outb_p(t, WDT_EFDR); /* set GPIO3 to WDT0 */ } else if (t == 0x88 || t == 0xa0) { /* W83627EHF / W83627DHG */ outb_p(0x2d, WDT_EFER); /* select GPIO5 */ t = inb_p(WDT_EFDR) & ~0x01; /* PIN77 -> WDT0# */ outb_p(0x2d, WDT_EFER); outb_p(t, WDT_EFDR); /* set GPIO5 to WDT0 */ } outb_p(0x30, WDT_EFER); /* select CR30 */ outb_p(0x01, WDT_EFDR); /* set bit 0 to activate GPIO2 */ outb_p(0xF6, WDT_EFER); /* Select CRF6 */ t = inb_p(WDT_EFDR); /* read CRF6 */ if (t != 0) { pr_info("Watchdog already running. Resetting timeout to %d sec\n", wdog->timeout); outb_p(wdog->timeout, WDT_EFDR); /* Write back to CRF6 */ } outb_p(0xF5, WDT_EFER); /* Select CRF5 */ t = inb_p(WDT_EFDR); /* read CRF5 */ t &= ~0x0C; /* set second mode & disable keyboard turning off watchdog */ t |= 0x02; /* enable the WDTO# output low pulse to the KBRST# pin (PIN60) */ outb_p(t, WDT_EFDR); /* Write back to CRF5 */ outb_p(0xF7, WDT_EFER); /* Select CRF7 */ t = inb_p(WDT_EFDR); /* read CRF7 */ t &= ~0xC0; /* disable keyboard & mouse turning off watchdog */ outb_p(t, WDT_EFDR); /* Write back to CRF7 */ w83627hf_unselect_wd_register(); } static int wdt_set_time(unsigned int timeout) { w83627hf_select_wd_register(); outb_p(0xF6, WDT_EFER); /* Select CRF6 */ outb_p(timeout, WDT_EFDR); /* Write Timeout counter to CRF6 */ w83627hf_unselect_wd_register(); return 0; } static int wdt_start(struct watchdog_device *wdog) { return wdt_set_time(wdog->timeout); } static int wdt_stop(struct watchdog_device *wdog) { return wdt_set_time(0); } static int wdt_set_timeout(struct watchdog_device *wdog, unsigned int timeout) { wdog->timeout = timeout; return 0; } static unsigned int wdt_get_time(struct watchdog_device *wdog) { unsigned int timeleft; w83627hf_select_wd_register(); outb_p(0xF6, WDT_EFER); /* Select CRF6 */ timeleft = inb_p(WDT_EFDR); /* Read Timeout counter to CRF6 */ w83627hf_unselect_wd_register(); return timeleft; } /* * Notifier for system down */ static int wdt_notify_sys(struct notifier_block *this, unsigned long code, void *unused) { if (code == SYS_DOWN || code == SYS_HALT) wdt_set_time(0); /* Turn the WDT off */ return NOTIFY_DONE; } /* * Kernel Interfaces */ static struct watchdog_info wdt_info = { .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, .identity = "W83627HF Watchdog", }; static struct watchdog_ops wdt_ops = { .owner = THIS_MODULE, .start = wdt_start, .stop = wdt_stop, .set_timeout = wdt_set_timeout, .get_timeleft = wdt_get_time, }; static struct watchdog_device wdt_dev = { .info = &wdt_info, .ops = &wdt_ops, .timeout = WATCHDOG_TIMEOUT, .min_timeout = 1, .max_timeout = 255, }; /* * The WDT needs to learn about soft shutdowns in order to * turn the timebomb registers off. */ static struct notifier_block wdt_notifier = { .notifier_call = wdt_notify_sys, }; static int __init wdt_init(void) { int ret; pr_info("WDT driver for the Winbond(TM) W83627HF/THF/HG/DHG Super I/O chip initialising\n"); if (!request_region(wdt_io, 1, WATCHDOG_NAME)) { pr_err("I/O address 0x%04x already in use\n", wdt_io); return -EIO; } watchdog_init_timeout(&wdt_dev, timeout, NULL); watchdog_set_nowayout(&wdt_dev, nowayout); w83627hf_init(&wdt_dev); ret = register_reboot_notifier(&wdt_notifier); if (ret != 0) { pr_err("cannot register reboot notifier (err=%d)\n", ret); goto unreg_regions; } ret = watchdog_register_device(&wdt_dev); if (ret) goto unreg_reboot; pr_info("initialized. timeout=%d sec (nowayout=%d)\n", wdt_dev.timeout, nowayout); return ret; unreg_reboot: unregister_reboot_notifier(&wdt_notifier); unreg_regions: release_region(wdt_io, 1); return ret; } static void __exit wdt_exit(void) { watchdog_unregister_device(&wdt_dev); unregister_reboot_notifier(&wdt_notifier); release_region(wdt_io, 1); } module_init(wdt_init); module_exit(wdt_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Pádraig Brady "); MODULE_DESCRIPTION("w83627hf/thf WDT driver");