1b7e04f8cSWim Van Sebroeck /* 204bedfa5SAlan Cox * Industrial Computer Source WDT501 driver 3b7e04f8cSWim Van Sebroeck * 429fa0586SAlan Cox * (c) Copyright 1996-1997 Alan Cox <alan@lxorguk.ukuu.org.uk>, 529fa0586SAlan Cox * All Rights Reserved. 6b7e04f8cSWim Van Sebroeck * 7b7e04f8cSWim Van Sebroeck * This program is free software; you can redistribute it and/or 8b7e04f8cSWim Van Sebroeck * modify it under the terms of the GNU General Public License 9b7e04f8cSWim Van Sebroeck * as published by the Free Software Foundation; either version 10b7e04f8cSWim Van Sebroeck * 2 of the License, or (at your option) any later version. 11b7e04f8cSWim Van Sebroeck * 12b7e04f8cSWim Van Sebroeck * Neither Alan Cox nor CymruNet Ltd. admit liability nor provide 13b7e04f8cSWim Van Sebroeck * warranty for any of this software. This material is provided 14b7e04f8cSWim Van Sebroeck * "AS-IS" and at no charge. 15b7e04f8cSWim Van Sebroeck * 16b7e04f8cSWim Van Sebroeck * (c) Copyright 1995 Alan Cox <alan@lxorguk.ukuu.org.uk> 17b7e04f8cSWim Van Sebroeck * 18b7e04f8cSWim Van Sebroeck * Release 0.10. 19b7e04f8cSWim Van Sebroeck * 20b7e04f8cSWim Van Sebroeck * Fixes 21b7e04f8cSWim Van Sebroeck * Dave Gregorich : Modularisation and minor bugs 22b7e04f8cSWim Van Sebroeck * Alan Cox : Added the watchdog ioctl() stuff 23b7e04f8cSWim Van Sebroeck * Alan Cox : Fixed the reboot problem (as noted by 24b7e04f8cSWim Van Sebroeck * Matt Crocker). 25b7e04f8cSWim Van Sebroeck * Alan Cox : Added wdt= boot option 26b7e04f8cSWim Van Sebroeck * Alan Cox : Cleaned up copy/user stuff 279f2d1f0dSAlan Cox * Tim Hockin : Added insmod parameters, comment 289f2d1f0dSAlan Cox * cleanup, parameterized timeout 299f2d1f0dSAlan Cox * Tigran Aivazian : Restructured wdt_init() to handle 309f2d1f0dSAlan Cox * failures 31b7e04f8cSWim Van Sebroeck * Joel Becker : Added WDIOC_GET/SETTIMEOUT 32b7e04f8cSWim Van Sebroeck * Matt Domsch : Added nowayout module option 33b7e04f8cSWim Van Sebroeck */ 34b7e04f8cSWim Van Sebroeck 35*27c766aaSJoe Perches #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 36*27c766aaSJoe Perches 37b7e04f8cSWim Van Sebroeck #include <linux/interrupt.h> 38b7e04f8cSWim Van Sebroeck #include <linux/module.h> 39b7e04f8cSWim Van Sebroeck #include <linux/moduleparam.h> 40b7e04f8cSWim Van Sebroeck #include <linux/types.h> 41b7e04f8cSWim Van Sebroeck #include <linux/miscdevice.h> 42b7e04f8cSWim Van Sebroeck #include <linux/watchdog.h> 43b7e04f8cSWim Van Sebroeck #include <linux/fs.h> 44b7e04f8cSWim Van Sebroeck #include <linux/ioport.h> 45b7e04f8cSWim Van Sebroeck #include <linux/notifier.h> 46b7e04f8cSWim Van Sebroeck #include <linux/reboot.h> 47b7e04f8cSWim Van Sebroeck #include <linux/init.h> 489f2d1f0dSAlan Cox #include <linux/io.h> 499f2d1f0dSAlan Cox #include <linux/uaccess.h> 50b7e04f8cSWim Van Sebroeck 51b7e04f8cSWim Van Sebroeck #include <asm/system.h> 52b7e04f8cSWim Van Sebroeck #include "wd501p.h" 53b7e04f8cSWim Van Sebroeck 54b7e04f8cSWim Van Sebroeck static unsigned long wdt_is_open; 55b7e04f8cSWim Van Sebroeck static char expect_close; 56b7e04f8cSWim Van Sebroeck 57b7e04f8cSWim Van Sebroeck /* 58b7e04f8cSWim Van Sebroeck * Module parameters 59b7e04f8cSWim Van Sebroeck */ 60b7e04f8cSWim Van Sebroeck 61b7e04f8cSWim Van Sebroeck #define WD_TIMO 60 /* Default heartbeat = 60 seconds */ 62b7e04f8cSWim Van Sebroeck 63b7e04f8cSWim Van Sebroeck static int heartbeat = WD_TIMO; 64b7e04f8cSWim Van Sebroeck static int wd_heartbeat; 65b7e04f8cSWim Van Sebroeck module_param(heartbeat, int, 0); 669f2d1f0dSAlan Cox MODULE_PARM_DESC(heartbeat, 679f2d1f0dSAlan Cox "Watchdog heartbeat in seconds. (0 < heartbeat < 65536, default=" 689f2d1f0dSAlan Cox __MODULE_STRING(WD_TIMO) ")"); 69b7e04f8cSWim Van Sebroeck 70b7e04f8cSWim Van Sebroeck static int nowayout = WATCHDOG_NOWAYOUT; 71b7e04f8cSWim Van Sebroeck module_param(nowayout, int, 0); 729f2d1f0dSAlan Cox MODULE_PARM_DESC(nowayout, 739f2d1f0dSAlan Cox "Watchdog cannot be stopped once started (default=" 749f2d1f0dSAlan Cox __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); 75b7e04f8cSWim Van Sebroeck 76b7e04f8cSWim Van Sebroeck /* You must set these - there is no sane way to probe for this board. */ 77b7e04f8cSWim Van Sebroeck static int io = 0x240; 78b7e04f8cSWim Van Sebroeck static int irq = 11; 79b7e04f8cSWim Van Sebroeck 8001c785dcSAlan Cox static DEFINE_SPINLOCK(wdt_lock); 8101c785dcSAlan Cox 82b7e04f8cSWim Van Sebroeck module_param(io, int, 0); 83b7e04f8cSWim Van Sebroeck MODULE_PARM_DESC(io, "WDT io port (default=0x240)"); 84b7e04f8cSWim Van Sebroeck module_param(irq, int, 0); 85b7e04f8cSWim Van Sebroeck MODULE_PARM_DESC(irq, "WDT irq (default=11)"); 86b7e04f8cSWim Van Sebroeck 87b7e04f8cSWim Van Sebroeck /* Support for the Fan Tachometer on the WDT501-P */ 88b7e04f8cSWim Van Sebroeck static int tachometer; 89b7e04f8cSWim Van Sebroeck module_param(tachometer, int, 0); 909f2d1f0dSAlan Cox MODULE_PARM_DESC(tachometer, 919f2d1f0dSAlan Cox "WDT501-P Fan Tachometer support (0=disable, default=0)"); 9204bedfa5SAlan Cox 9304bedfa5SAlan Cox static int type = 500; 9404bedfa5SAlan Cox module_param(type, int, 0); 9504bedfa5SAlan Cox MODULE_PARM_DESC(type, 9604bedfa5SAlan Cox "WDT501-P Card type (500 or 501, default=500)"); 97b7e04f8cSWim Van Sebroeck 98b7e04f8cSWim Van Sebroeck /* 99b7e04f8cSWim Van Sebroeck * Programming support 100b7e04f8cSWim Van Sebroeck */ 101b7e04f8cSWim Van Sebroeck 102b7e04f8cSWim Van Sebroeck static void wdt_ctr_mode(int ctr, int mode) 103b7e04f8cSWim Van Sebroeck { 104b7e04f8cSWim Van Sebroeck ctr <<= 6; 105b7e04f8cSWim Van Sebroeck ctr |= 0x30; 106b7e04f8cSWim Van Sebroeck ctr |= (mode << 1); 107b7e04f8cSWim Van Sebroeck outb_p(ctr, WDT_CR); 108b7e04f8cSWim Van Sebroeck } 109b7e04f8cSWim Van Sebroeck 110b7e04f8cSWim Van Sebroeck static void wdt_ctr_load(int ctr, int val) 111b7e04f8cSWim Van Sebroeck { 112b7e04f8cSWim Van Sebroeck outb_p(val&0xFF, WDT_COUNT0+ctr); 113b7e04f8cSWim Van Sebroeck outb_p(val>>8, WDT_COUNT0+ctr); 114b7e04f8cSWim Van Sebroeck } 115b7e04f8cSWim Van Sebroeck 116b7e04f8cSWim Van Sebroeck /** 117b7e04f8cSWim Van Sebroeck * wdt_start: 118b7e04f8cSWim Van Sebroeck * 119b7e04f8cSWim Van Sebroeck * Start the watchdog driver. 120b7e04f8cSWim Van Sebroeck */ 121b7e04f8cSWim Van Sebroeck 122b7e04f8cSWim Van Sebroeck static int wdt_start(void) 123b7e04f8cSWim Van Sebroeck { 12401c785dcSAlan Cox unsigned long flags; 12501c785dcSAlan Cox spin_lock_irqsave(&wdt_lock, flags); 126b7e04f8cSWim Van Sebroeck inb_p(WDT_DC); /* Disable watchdog */ 1279f2d1f0dSAlan Cox wdt_ctr_mode(0, 3); /* Program CTR0 for Mode 3: 1289f2d1f0dSAlan Cox Square Wave Generator */ 1299f2d1f0dSAlan Cox wdt_ctr_mode(1, 2); /* Program CTR1 for Mode 2: 1309f2d1f0dSAlan Cox Rate Generator */ 1319f2d1f0dSAlan Cox wdt_ctr_mode(2, 0); /* Program CTR2 for Mode 0: 1329f2d1f0dSAlan Cox Pulse on Terminal Count */ 133b7e04f8cSWim Van Sebroeck wdt_ctr_load(0, 8948); /* Count at 100Hz */ 134b7e04f8cSWim Van Sebroeck wdt_ctr_load(1, wd_heartbeat); /* Heartbeat */ 135b7e04f8cSWim Van Sebroeck wdt_ctr_load(2, 65535); /* Length of reset pulse */ 136b7e04f8cSWim Van Sebroeck outb_p(0, WDT_DC); /* Enable watchdog */ 13701c785dcSAlan Cox spin_unlock_irqrestore(&wdt_lock, flags); 138b7e04f8cSWim Van Sebroeck return 0; 139b7e04f8cSWim Van Sebroeck } 140b7e04f8cSWim Van Sebroeck 141b7e04f8cSWim Van Sebroeck /** 142b7e04f8cSWim Van Sebroeck * wdt_stop: 143b7e04f8cSWim Van Sebroeck * 144b7e04f8cSWim Van Sebroeck * Stop the watchdog driver. 145b7e04f8cSWim Van Sebroeck */ 146b7e04f8cSWim Van Sebroeck 147b7e04f8cSWim Van Sebroeck static int wdt_stop(void) 148b7e04f8cSWim Van Sebroeck { 14901c785dcSAlan Cox unsigned long flags; 15001c785dcSAlan Cox spin_lock_irqsave(&wdt_lock, flags); 151b7e04f8cSWim Van Sebroeck /* Turn the card off */ 152b7e04f8cSWim Van Sebroeck inb_p(WDT_DC); /* Disable watchdog */ 153b7e04f8cSWim Van Sebroeck wdt_ctr_load(2, 0); /* 0 length reset pulses now */ 15401c785dcSAlan Cox spin_unlock_irqrestore(&wdt_lock, flags); 155b7e04f8cSWim Van Sebroeck return 0; 156b7e04f8cSWim Van Sebroeck } 157b7e04f8cSWim Van Sebroeck 158b7e04f8cSWim Van Sebroeck /** 159b7e04f8cSWim Van Sebroeck * wdt_ping: 160b7e04f8cSWim Van Sebroeck * 1619f2d1f0dSAlan Cox * Reload counter one with the watchdog heartbeat. We don't bother 1629f2d1f0dSAlan Cox * reloading the cascade counter. 163b7e04f8cSWim Van Sebroeck */ 164b7e04f8cSWim Van Sebroeck 16504bedfa5SAlan Cox static void wdt_ping(void) 166b7e04f8cSWim Van Sebroeck { 16701c785dcSAlan Cox unsigned long flags; 16801c785dcSAlan Cox spin_lock_irqsave(&wdt_lock, flags); 169b7e04f8cSWim Van Sebroeck /* Write a watchdog value */ 170b7e04f8cSWim Van Sebroeck inb_p(WDT_DC); /* Disable watchdog */ 1719f2d1f0dSAlan Cox wdt_ctr_mode(1, 2); /* Re-Program CTR1 for Mode 2: 1729f2d1f0dSAlan Cox Rate Generator */ 173b7e04f8cSWim Van Sebroeck wdt_ctr_load(1, wd_heartbeat); /* Heartbeat */ 174b7e04f8cSWim Van Sebroeck outb_p(0, WDT_DC); /* Enable watchdog */ 17501c785dcSAlan Cox spin_unlock_irqrestore(&wdt_lock, flags); 176b7e04f8cSWim Van Sebroeck } 177b7e04f8cSWim Van Sebroeck 178b7e04f8cSWim Van Sebroeck /** 179b7e04f8cSWim Van Sebroeck * wdt_set_heartbeat: 180b7e04f8cSWim Van Sebroeck * @t: the new heartbeat value that needs to be set. 181b7e04f8cSWim Van Sebroeck * 1829f2d1f0dSAlan Cox * Set a new heartbeat value for the watchdog device. If the heartbeat 1839f2d1f0dSAlan Cox * value is incorrect we keep the old value and return -EINVAL. If 1849f2d1f0dSAlan Cox * successful we return 0. 185b7e04f8cSWim Van Sebroeck */ 1869f2d1f0dSAlan Cox 187b7e04f8cSWim Van Sebroeck static int wdt_set_heartbeat(int t) 188b7e04f8cSWim Van Sebroeck { 1899f2d1f0dSAlan Cox if (t < 1 || t > 65535) 190b7e04f8cSWim Van Sebroeck return -EINVAL; 191b7e04f8cSWim Van Sebroeck 192b7e04f8cSWim Van Sebroeck heartbeat = t; 193b7e04f8cSWim Van Sebroeck wd_heartbeat = t * 100; 194b7e04f8cSWim Van Sebroeck return 0; 195b7e04f8cSWim Van Sebroeck } 196b7e04f8cSWim Van Sebroeck 197b7e04f8cSWim Van Sebroeck /** 198b7e04f8cSWim Van Sebroeck * wdt_get_status: 199b7e04f8cSWim Van Sebroeck * 200b7e04f8cSWim Van Sebroeck * Extract the status information from a WDT watchdog device. There are 201b7e04f8cSWim Van Sebroeck * several board variants so we have to know which bits are valid. Some 202b7e04f8cSWim Van Sebroeck * bits default to one and some to zero in order to be maximally painful. 203b7e04f8cSWim Van Sebroeck * 204b7e04f8cSWim Van Sebroeck * we then map the bits onto the status ioctl flags. 205b7e04f8cSWim Van Sebroeck */ 206b7e04f8cSWim Van Sebroeck 20704bedfa5SAlan Cox static int wdt_get_status(void) 208b7e04f8cSWim Van Sebroeck { 20901c785dcSAlan Cox unsigned char new_status; 21004bedfa5SAlan Cox int status = 0; 21101c785dcSAlan Cox unsigned long flags; 21201c785dcSAlan Cox 21301c785dcSAlan Cox spin_lock_irqsave(&wdt_lock, flags); 21401c785dcSAlan Cox new_status = inb_p(WDT_SR); 21501c785dcSAlan Cox spin_unlock_irqrestore(&wdt_lock, flags); 216b7e04f8cSWim Van Sebroeck 217b7e04f8cSWim Van Sebroeck if (new_status & WDC_SR_ISOI0) 21804bedfa5SAlan Cox status |= WDIOF_EXTERN1; 219b7e04f8cSWim Van Sebroeck if (new_status & WDC_SR_ISII1) 22004bedfa5SAlan Cox status |= WDIOF_EXTERN2; 22104bedfa5SAlan Cox if (type == 501) { 222b7e04f8cSWim Van Sebroeck if (!(new_status & WDC_SR_TGOOD)) 22304bedfa5SAlan Cox status |= WDIOF_OVERHEAT; 224b7e04f8cSWim Van Sebroeck if (!(new_status & WDC_SR_PSUOVER)) 22504bedfa5SAlan Cox status |= WDIOF_POWEROVER; 226b7e04f8cSWim Van Sebroeck if (!(new_status & WDC_SR_PSUUNDR)) 22704bedfa5SAlan Cox status |= WDIOF_POWERUNDER; 228b7e04f8cSWim Van Sebroeck if (tachometer) { 229b7e04f8cSWim Van Sebroeck if (!(new_status & WDC_SR_FANGOOD)) 23004bedfa5SAlan Cox status |= WDIOF_FANFAULT; 231b7e04f8cSWim Van Sebroeck } 23204bedfa5SAlan Cox } 23304bedfa5SAlan Cox return status; 234b7e04f8cSWim Van Sebroeck } 235b7e04f8cSWim Van Sebroeck 236b7e04f8cSWim Van Sebroeck /** 237b7e04f8cSWim Van Sebroeck * wdt_get_temperature: 238b7e04f8cSWim Van Sebroeck * 239b7e04f8cSWim Van Sebroeck * Reports the temperature in degrees Fahrenheit. The API is in 240b7e04f8cSWim Van Sebroeck * farenheit. It was designed by an imperial measurement luddite. 241b7e04f8cSWim Van Sebroeck */ 242b7e04f8cSWim Van Sebroeck 24304bedfa5SAlan Cox static int wdt_get_temperature(void) 244b7e04f8cSWim Van Sebroeck { 24501c785dcSAlan Cox unsigned short c; 24601c785dcSAlan Cox unsigned long flags; 247b7e04f8cSWim Van Sebroeck 24801c785dcSAlan Cox spin_lock_irqsave(&wdt_lock, flags); 24901c785dcSAlan Cox c = inb_p(WDT_RT); 25001c785dcSAlan Cox spin_unlock_irqrestore(&wdt_lock, flags); 25104bedfa5SAlan Cox return (c * 11 / 15) + 7; 252b7e04f8cSWim Van Sebroeck } 25304bedfa5SAlan Cox 25404bedfa5SAlan Cox static void wdt_decode_501(int status) 25504bedfa5SAlan Cox { 25604bedfa5SAlan Cox if (!(status & WDC_SR_TGOOD)) 257*27c766aaSJoe Perches pr_crit("Overheat alarm (%d)\n", inb_p(WDT_RT)); 25804bedfa5SAlan Cox if (!(status & WDC_SR_PSUOVER)) 259*27c766aaSJoe Perches pr_crit("PSU over voltage\n"); 26004bedfa5SAlan Cox if (!(status & WDC_SR_PSUUNDR)) 261*27c766aaSJoe Perches pr_crit("PSU under voltage\n"); 26204bedfa5SAlan Cox } 263b7e04f8cSWim Van Sebroeck 264b7e04f8cSWim Van Sebroeck /** 265b7e04f8cSWim Van Sebroeck * wdt_interrupt: 266b7e04f8cSWim Van Sebroeck * @irq: Interrupt number 267b7e04f8cSWim Van Sebroeck * @dev_id: Unused as we don't allow multiple devices. 268b7e04f8cSWim Van Sebroeck * 269b7e04f8cSWim Van Sebroeck * Handle an interrupt from the board. These are raised when the status 270b7e04f8cSWim Van Sebroeck * map changes in what the board considers an interesting way. That means 271b7e04f8cSWim Van Sebroeck * a failure condition occurring. 272b7e04f8cSWim Van Sebroeck */ 273b7e04f8cSWim Van Sebroeck 274b7e04f8cSWim Van Sebroeck static irqreturn_t wdt_interrupt(int irq, void *dev_id) 275b7e04f8cSWim Van Sebroeck { 276b7e04f8cSWim Van Sebroeck /* 277b7e04f8cSWim Van Sebroeck * Read the status register see what is up and 278b7e04f8cSWim Van Sebroeck * then printk it. 279b7e04f8cSWim Van Sebroeck */ 28001c785dcSAlan Cox unsigned char status; 28101c785dcSAlan Cox 28201c785dcSAlan Cox spin_lock(&wdt_lock); 28301c785dcSAlan Cox status = inb_p(WDT_SR); 284b7e04f8cSWim Van Sebroeck 285*27c766aaSJoe Perches pr_crit("WDT status %d\n", status); 286b7e04f8cSWim Van Sebroeck 28704bedfa5SAlan Cox if (type == 501) { 28804bedfa5SAlan Cox wdt_decode_501(status); 289b7e04f8cSWim Van Sebroeck if (tachometer) { 290b7e04f8cSWim Van Sebroeck if (!(status & WDC_SR_FANGOOD)) 291*27c766aaSJoe Perches pr_crit("Possible fan fault\n"); 292b7e04f8cSWim Van Sebroeck } 29304bedfa5SAlan Cox } 29459338d4cSIlpo Jarvinen if (!(status & WDC_SR_WCCR)) { 295b7e04f8cSWim Van Sebroeck #ifdef SOFTWARE_REBOOT 296b7e04f8cSWim Van Sebroeck #ifdef ONLY_TESTING 297*27c766aaSJoe Perches pr_crit("Would Reboot\n"); 298b7e04f8cSWim Van Sebroeck #else 299*27c766aaSJoe Perches pr_crit("Initiating system reboot\n"); 300b7e04f8cSWim Van Sebroeck emergency_restart(); 301b7e04f8cSWim Van Sebroeck #endif 302b7e04f8cSWim Van Sebroeck #else 303*27c766aaSJoe Perches pr_crit("Reset in 5ms\n"); 304b7e04f8cSWim Van Sebroeck #endif 30559338d4cSIlpo Jarvinen } 30601c785dcSAlan Cox spin_unlock(&wdt_lock); 307b7e04f8cSWim Van Sebroeck return IRQ_HANDLED; 308b7e04f8cSWim Van Sebroeck } 309b7e04f8cSWim Van Sebroeck 310b7e04f8cSWim Van Sebroeck 311b7e04f8cSWim Van Sebroeck /** 312b7e04f8cSWim Van Sebroeck * wdt_write: 313b7e04f8cSWim Van Sebroeck * @file: file handle to the watchdog 314b7e04f8cSWim Van Sebroeck * @buf: buffer to write (unused as data does not matter here 315b7e04f8cSWim Van Sebroeck * @count: count of bytes 316b7e04f8cSWim Van Sebroeck * @ppos: pointer to the position to write. No seeks allowed 317b7e04f8cSWim Van Sebroeck * 318b7e04f8cSWim Van Sebroeck * A write to a watchdog device is defined as a keepalive signal. Any 319b7e04f8cSWim Van Sebroeck * write of data will do, as we we don't define content meaning. 320b7e04f8cSWim Van Sebroeck */ 321b7e04f8cSWim Van Sebroeck 3229f2d1f0dSAlan Cox static ssize_t wdt_write(struct file *file, const char __user *buf, 3239f2d1f0dSAlan Cox size_t count, loff_t *ppos) 324b7e04f8cSWim Van Sebroeck { 325b7e04f8cSWim Van Sebroeck if (count) { 326b7e04f8cSWim Van Sebroeck if (!nowayout) { 327b7e04f8cSWim Van Sebroeck size_t i; 328b7e04f8cSWim Van Sebroeck 329b7e04f8cSWim Van Sebroeck /* In case it was set long ago */ 330b7e04f8cSWim Van Sebroeck expect_close = 0; 331b7e04f8cSWim Van Sebroeck 332b7e04f8cSWim Van Sebroeck for (i = 0; i != count; i++) { 333b7e04f8cSWim Van Sebroeck char c; 334b7e04f8cSWim Van Sebroeck if (get_user(c, buf + i)) 335b7e04f8cSWim Van Sebroeck return -EFAULT; 336b7e04f8cSWim Van Sebroeck if (c == 'V') 337b7e04f8cSWim Van Sebroeck expect_close = 42; 338b7e04f8cSWim Van Sebroeck } 339b7e04f8cSWim Van Sebroeck } 340b7e04f8cSWim Van Sebroeck wdt_ping(); 341b7e04f8cSWim Van Sebroeck } 342b7e04f8cSWim Van Sebroeck return count; 343b7e04f8cSWim Van Sebroeck } 344b7e04f8cSWim Van Sebroeck 345b7e04f8cSWim Van Sebroeck /** 346b7e04f8cSWim Van Sebroeck * wdt_ioctl: 347b7e04f8cSWim Van Sebroeck * @file: file handle to the device 348b7e04f8cSWim Van Sebroeck * @cmd: watchdog command 349b7e04f8cSWim Van Sebroeck * @arg: argument pointer 350b7e04f8cSWim Van Sebroeck * 351b7e04f8cSWim Van Sebroeck * The watchdog API defines a common set of functions for all watchdogs 352b7e04f8cSWim Van Sebroeck * according to their available features. We only actually usefully support 353b7e04f8cSWim Van Sebroeck * querying capabilities and current status. 354b7e04f8cSWim Van Sebroeck */ 355b7e04f8cSWim Van Sebroeck 3569f2d1f0dSAlan Cox static long wdt_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 357b7e04f8cSWim Van Sebroeck { 358b7e04f8cSWim Van Sebroeck void __user *argp = (void __user *)arg; 359b7e04f8cSWim Van Sebroeck int __user *p = argp; 360b7e04f8cSWim Van Sebroeck int new_heartbeat; 361b7e04f8cSWim Van Sebroeck int status; 362b7e04f8cSWim Van Sebroeck 363c1bf3acfSAndrew Morton struct watchdog_info ident = { 364b7e04f8cSWim Van Sebroeck .options = WDIOF_SETTIMEOUT| 365b7e04f8cSWim Van Sebroeck WDIOF_MAGICCLOSE| 366b7e04f8cSWim Van Sebroeck WDIOF_KEEPALIVEPING, 367b7e04f8cSWim Van Sebroeck .firmware_version = 1, 368b7e04f8cSWim Van Sebroeck .identity = "WDT500/501", 369b7e04f8cSWim Van Sebroeck }; 370b7e04f8cSWim Van Sebroeck 371b7e04f8cSWim Van Sebroeck /* Add options according to the card we have */ 372b7e04f8cSWim Van Sebroeck ident.options |= (WDIOF_EXTERN1|WDIOF_EXTERN2); 37304bedfa5SAlan Cox if (type == 501) { 37404bedfa5SAlan Cox ident.options |= (WDIOF_OVERHEAT|WDIOF_POWERUNDER| 37504bedfa5SAlan Cox WDIOF_POWEROVER); 376b7e04f8cSWim Van Sebroeck if (tachometer) 377b7e04f8cSWim Van Sebroeck ident.options |= WDIOF_FANFAULT; 37804bedfa5SAlan Cox } 379b7e04f8cSWim Van Sebroeck 3809f2d1f0dSAlan Cox switch (cmd) { 381b7e04f8cSWim Van Sebroeck case WDIOC_GETSUPPORT: 382b7e04f8cSWim Van Sebroeck return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0; 383b7e04f8cSWim Van Sebroeck case WDIOC_GETSTATUS: 38404bedfa5SAlan Cox status = wdt_get_status(); 385b7e04f8cSWim Van Sebroeck return put_user(status, p); 386b7e04f8cSWim Van Sebroeck case WDIOC_GETBOOTSTATUS: 387b7e04f8cSWim Van Sebroeck return put_user(0, p); 388b7e04f8cSWim Van Sebroeck case WDIOC_KEEPALIVE: 389b7e04f8cSWim Van Sebroeck wdt_ping(); 390b7e04f8cSWim Van Sebroeck return 0; 391b7e04f8cSWim Van Sebroeck case WDIOC_SETTIMEOUT: 392b7e04f8cSWim Van Sebroeck if (get_user(new_heartbeat, p)) 393b7e04f8cSWim Van Sebroeck return -EFAULT; 394b7e04f8cSWim Van Sebroeck if (wdt_set_heartbeat(new_heartbeat)) 395b7e04f8cSWim Van Sebroeck return -EINVAL; 396b7e04f8cSWim Van Sebroeck wdt_ping(); 397b7e04f8cSWim Van Sebroeck /* Fall */ 398b7e04f8cSWim Van Sebroeck case WDIOC_GETTIMEOUT: 399b7e04f8cSWim Van Sebroeck return put_user(heartbeat, p); 4000c06090cSWim Van Sebroeck default: 4010c06090cSWim Van Sebroeck return -ENOTTY; 402b7e04f8cSWim Van Sebroeck } 403b7e04f8cSWim Van Sebroeck } 404b7e04f8cSWim Van Sebroeck 405b7e04f8cSWim Van Sebroeck /** 406b7e04f8cSWim Van Sebroeck * wdt_open: 407b7e04f8cSWim Van Sebroeck * @inode: inode of device 408b7e04f8cSWim Van Sebroeck * @file: file handle to device 409b7e04f8cSWim Van Sebroeck * 410b7e04f8cSWim Van Sebroeck * The watchdog device has been opened. The watchdog device is single 411b7e04f8cSWim Van Sebroeck * open and on opening we load the counters. Counter zero is a 100Hz 412b7e04f8cSWim Van Sebroeck * cascade, into counter 1 which downcounts to reboot. When the counter 413b7e04f8cSWim Van Sebroeck * triggers counter 2 downcounts the length of the reset pulse which 414b7e04f8cSWim Van Sebroeck * set set to be as long as possible. 415b7e04f8cSWim Van Sebroeck */ 416b7e04f8cSWim Van Sebroeck 417b7e04f8cSWim Van Sebroeck static int wdt_open(struct inode *inode, struct file *file) 418b7e04f8cSWim Van Sebroeck { 419b7e04f8cSWim Van Sebroeck if (test_and_set_bit(0, &wdt_is_open)) 420b7e04f8cSWim Van Sebroeck return -EBUSY; 421b7e04f8cSWim Van Sebroeck /* 422b7e04f8cSWim Van Sebroeck * Activate 423b7e04f8cSWim Van Sebroeck */ 424b7e04f8cSWim Van Sebroeck wdt_start(); 425b7e04f8cSWim Van Sebroeck return nonseekable_open(inode, file); 426b7e04f8cSWim Van Sebroeck } 427b7e04f8cSWim Van Sebroeck 428b7e04f8cSWim Van Sebroeck /** 429b7e04f8cSWim Van Sebroeck * wdt_release: 430b7e04f8cSWim Van Sebroeck * @inode: inode to board 431b7e04f8cSWim Van Sebroeck * @file: file handle to board 432b7e04f8cSWim Van Sebroeck * 433b7e04f8cSWim Van Sebroeck * The watchdog has a configurable API. There is a religious dispute 434b7e04f8cSWim Van Sebroeck * between people who want their watchdog to be able to shut down and 435b7e04f8cSWim Van Sebroeck * those who want to be sure if the watchdog manager dies the machine 436b7e04f8cSWim Van Sebroeck * reboots. In the former case we disable the counters, in the latter 437b7e04f8cSWim Van Sebroeck * case you have to open it again very soon. 438b7e04f8cSWim Van Sebroeck */ 439b7e04f8cSWim Van Sebroeck 440b7e04f8cSWim Van Sebroeck static int wdt_release(struct inode *inode, struct file *file) 441b7e04f8cSWim Van Sebroeck { 442b7e04f8cSWim Van Sebroeck if (expect_close == 42) { 443b7e04f8cSWim Van Sebroeck wdt_stop(); 444b7e04f8cSWim Van Sebroeck clear_bit(0, &wdt_is_open); 445b7e04f8cSWim Van Sebroeck } else { 446*27c766aaSJoe Perches pr_crit("WDT device closed unexpectedly. WDT will not stop!\n"); 447b7e04f8cSWim Van Sebroeck wdt_ping(); 448b7e04f8cSWim Van Sebroeck } 449b7e04f8cSWim Van Sebroeck expect_close = 0; 450b7e04f8cSWim Van Sebroeck return 0; 451b7e04f8cSWim Van Sebroeck } 452b7e04f8cSWim Van Sebroeck 453b7e04f8cSWim Van Sebroeck /** 454b7e04f8cSWim Van Sebroeck * wdt_temp_read: 455b7e04f8cSWim Van Sebroeck * @file: file handle to the watchdog board 456b7e04f8cSWim Van Sebroeck * @buf: buffer to write 1 byte into 457b7e04f8cSWim Van Sebroeck * @count: length of buffer 458b7e04f8cSWim Van Sebroeck * @ptr: offset (no seek allowed) 459b7e04f8cSWim Van Sebroeck * 460b7e04f8cSWim Van Sebroeck * Temp_read reports the temperature in degrees Fahrenheit. The API is in 461b7e04f8cSWim Van Sebroeck * farenheit. It was designed by an imperial measurement luddite. 462b7e04f8cSWim Van Sebroeck */ 463b7e04f8cSWim Van Sebroeck 4649f2d1f0dSAlan Cox static ssize_t wdt_temp_read(struct file *file, char __user *buf, 4659f2d1f0dSAlan Cox size_t count, loff_t *ptr) 466b7e04f8cSWim Van Sebroeck { 46704bedfa5SAlan Cox int temperature = wdt_get_temperature(); 468b7e04f8cSWim Van Sebroeck 469b7e04f8cSWim Van Sebroeck if (copy_to_user(buf, &temperature, 1)) 470b7e04f8cSWim Van Sebroeck return -EFAULT; 471b7e04f8cSWim Van Sebroeck 472b7e04f8cSWim Van Sebroeck return 1; 473b7e04f8cSWim Van Sebroeck } 474b7e04f8cSWim Van Sebroeck 475b7e04f8cSWim Van Sebroeck /** 476b7e04f8cSWim Van Sebroeck * wdt_temp_open: 477b7e04f8cSWim Van Sebroeck * @inode: inode of device 478b7e04f8cSWim Van Sebroeck * @file: file handle to device 479b7e04f8cSWim Van Sebroeck * 480b7e04f8cSWim Van Sebroeck * The temperature device has been opened. 481b7e04f8cSWim Van Sebroeck */ 482b7e04f8cSWim Van Sebroeck 483b7e04f8cSWim Van Sebroeck static int wdt_temp_open(struct inode *inode, struct file *file) 484b7e04f8cSWim Van Sebroeck { 485b7e04f8cSWim Van Sebroeck return nonseekable_open(inode, file); 486b7e04f8cSWim Van Sebroeck } 487b7e04f8cSWim Van Sebroeck 488b7e04f8cSWim Van Sebroeck /** 489b7e04f8cSWim Van Sebroeck * wdt_temp_release: 490b7e04f8cSWim Van Sebroeck * @inode: inode to board 491b7e04f8cSWim Van Sebroeck * @file: file handle to board 492b7e04f8cSWim Van Sebroeck * 493b7e04f8cSWim Van Sebroeck * The temperature device has been closed. 494b7e04f8cSWim Van Sebroeck */ 495b7e04f8cSWim Van Sebroeck 496b7e04f8cSWim Van Sebroeck static int wdt_temp_release(struct inode *inode, struct file *file) 497b7e04f8cSWim Van Sebroeck { 498b7e04f8cSWim Van Sebroeck return 0; 499b7e04f8cSWim Van Sebroeck } 500b7e04f8cSWim Van Sebroeck 501b7e04f8cSWim Van Sebroeck /** 502b7e04f8cSWim Van Sebroeck * notify_sys: 503b7e04f8cSWim Van Sebroeck * @this: our notifier block 504b7e04f8cSWim Van Sebroeck * @code: the event being reported 505b7e04f8cSWim Van Sebroeck * @unused: unused 506b7e04f8cSWim Van Sebroeck * 507b7e04f8cSWim Van Sebroeck * Our notifier is called on system shutdowns. We want to turn the card 508b7e04f8cSWim Van Sebroeck * off at reboot otherwise the machine will reboot again during memory 509b7e04f8cSWim Van Sebroeck * test or worse yet during the following fsck. This would suck, in fact 510b7e04f8cSWim Van Sebroeck * trust me - if it happens it does suck. 511b7e04f8cSWim Van Sebroeck */ 512b7e04f8cSWim Van Sebroeck 513b7e04f8cSWim Van Sebroeck static int wdt_notify_sys(struct notifier_block *this, unsigned long code, 514b7e04f8cSWim Van Sebroeck void *unused) 515b7e04f8cSWim Van Sebroeck { 5169f2d1f0dSAlan Cox if (code == SYS_DOWN || code == SYS_HALT) 517b7e04f8cSWim Van Sebroeck wdt_stop(); 518b7e04f8cSWim Van Sebroeck return NOTIFY_DONE; 519b7e04f8cSWim Van Sebroeck } 520b7e04f8cSWim Van Sebroeck 521b7e04f8cSWim Van Sebroeck /* 522b7e04f8cSWim Van Sebroeck * Kernel Interfaces 523b7e04f8cSWim Van Sebroeck */ 524b7e04f8cSWim Van Sebroeck 525b7e04f8cSWim Van Sebroeck 526b7e04f8cSWim Van Sebroeck static const struct file_operations wdt_fops = { 527b7e04f8cSWim Van Sebroeck .owner = THIS_MODULE, 528b7e04f8cSWim Van Sebroeck .llseek = no_llseek, 529b7e04f8cSWim Van Sebroeck .write = wdt_write, 5309f2d1f0dSAlan Cox .unlocked_ioctl = wdt_ioctl, 531b7e04f8cSWim Van Sebroeck .open = wdt_open, 532b7e04f8cSWim Van Sebroeck .release = wdt_release, 533b7e04f8cSWim Van Sebroeck }; 534b7e04f8cSWim Van Sebroeck 535b7e04f8cSWim Van Sebroeck static struct miscdevice wdt_miscdev = { 536b7e04f8cSWim Van Sebroeck .minor = WATCHDOG_MINOR, 537b7e04f8cSWim Van Sebroeck .name = "watchdog", 538b7e04f8cSWim Van Sebroeck .fops = &wdt_fops, 539b7e04f8cSWim Van Sebroeck }; 540b7e04f8cSWim Van Sebroeck 541b7e04f8cSWim Van Sebroeck static const struct file_operations wdt_temp_fops = { 542b7e04f8cSWim Van Sebroeck .owner = THIS_MODULE, 543b7e04f8cSWim Van Sebroeck .llseek = no_llseek, 544b7e04f8cSWim Van Sebroeck .read = wdt_temp_read, 545b7e04f8cSWim Van Sebroeck .open = wdt_temp_open, 546b7e04f8cSWim Van Sebroeck .release = wdt_temp_release, 547b7e04f8cSWim Van Sebroeck }; 548b7e04f8cSWim Van Sebroeck 549b7e04f8cSWim Van Sebroeck static struct miscdevice temp_miscdev = { 550b7e04f8cSWim Van Sebroeck .minor = TEMP_MINOR, 551b7e04f8cSWim Van Sebroeck .name = "temperature", 552b7e04f8cSWim Van Sebroeck .fops = &wdt_temp_fops, 553b7e04f8cSWim Van Sebroeck }; 554b7e04f8cSWim Van Sebroeck 555b7e04f8cSWim Van Sebroeck /* 556b7e04f8cSWim Van Sebroeck * The WDT card needs to learn about soft shutdowns in order to 557b7e04f8cSWim Van Sebroeck * turn the timebomb registers off. 558b7e04f8cSWim Van Sebroeck */ 559b7e04f8cSWim Van Sebroeck 560b7e04f8cSWim Van Sebroeck static struct notifier_block wdt_notifier = { 561b7e04f8cSWim Van Sebroeck .notifier_call = wdt_notify_sys, 562b7e04f8cSWim Van Sebroeck }; 563b7e04f8cSWim Van Sebroeck 564b7e04f8cSWim Van Sebroeck /** 565b7e04f8cSWim Van Sebroeck * cleanup_module: 566b7e04f8cSWim Van Sebroeck * 567b7e04f8cSWim Van Sebroeck * Unload the watchdog. You cannot do this with any file handles open. 568b7e04f8cSWim Van Sebroeck * If your watchdog is set to continue ticking on close and you unload 569b7e04f8cSWim Van Sebroeck * it, well it keeps ticking. We won't get the interrupt but the board 570b7e04f8cSWim Van Sebroeck * will not touch PC memory so all is fine. You just have to load a new 571b7e04f8cSWim Van Sebroeck * module in 60 seconds or reboot. 572b7e04f8cSWim Van Sebroeck */ 573b7e04f8cSWim Van Sebroeck 574b7e04f8cSWim Van Sebroeck static void __exit wdt_exit(void) 575b7e04f8cSWim Van Sebroeck { 576b7e04f8cSWim Van Sebroeck misc_deregister(&wdt_miscdev); 57704bedfa5SAlan Cox if (type == 501) 578b7e04f8cSWim Van Sebroeck misc_deregister(&temp_miscdev); 579b7e04f8cSWim Van Sebroeck unregister_reboot_notifier(&wdt_notifier); 580b7e04f8cSWim Van Sebroeck free_irq(irq, NULL); 581b7e04f8cSWim Van Sebroeck release_region(io, 8); 582b7e04f8cSWim Van Sebroeck } 583b7e04f8cSWim Van Sebroeck 584b7e04f8cSWim Van Sebroeck /** 585b7e04f8cSWim Van Sebroeck * wdt_init: 586b7e04f8cSWim Van Sebroeck * 587b7e04f8cSWim Van Sebroeck * Set up the WDT watchdog board. All we have to do is grab the 588b7e04f8cSWim Van Sebroeck * resources we require and bitch if anyone beat us to them. 589b7e04f8cSWim Van Sebroeck * The open() function will actually kick the board off. 590b7e04f8cSWim Van Sebroeck */ 591b7e04f8cSWim Van Sebroeck 592b7e04f8cSWim Van Sebroeck static int __init wdt_init(void) 593b7e04f8cSWim Van Sebroeck { 594b7e04f8cSWim Van Sebroeck int ret; 595b7e04f8cSWim Van Sebroeck 59604bedfa5SAlan Cox if (type != 500 && type != 501) { 597*27c766aaSJoe Perches pr_err("unknown card type '%d'\n", type); 59804bedfa5SAlan Cox return -ENODEV; 59904bedfa5SAlan Cox } 60004bedfa5SAlan Cox 6019f2d1f0dSAlan Cox /* Check that the heartbeat value is within it's range; 6029f2d1f0dSAlan Cox if not reset to the default */ 603b7e04f8cSWim Van Sebroeck if (wdt_set_heartbeat(heartbeat)) { 604b7e04f8cSWim Van Sebroeck wdt_set_heartbeat(WD_TIMO); 605*27c766aaSJoe Perches pr_info("heartbeat value must be 0 < heartbeat < 65536, using %d\n", 606*27c766aaSJoe Perches WD_TIMO); 607b7e04f8cSWim Van Sebroeck } 608b7e04f8cSWim Van Sebroeck 609b7e04f8cSWim Van Sebroeck if (!request_region(io, 8, "wdt501p")) { 610*27c766aaSJoe Perches pr_err("I/O address 0x%04x already in use\n", io); 611b7e04f8cSWim Van Sebroeck ret = -EBUSY; 612b7e04f8cSWim Van Sebroeck goto out; 613b7e04f8cSWim Van Sebroeck } 614b7e04f8cSWim Van Sebroeck 61586b59128SYong Zhang ret = request_irq(irq, wdt_interrupt, 0, "wdt501p", NULL); 616b7e04f8cSWim Van Sebroeck if (ret) { 617*27c766aaSJoe Perches pr_err("IRQ %d is not free\n", irq); 618b7e04f8cSWim Van Sebroeck goto outreg; 619b7e04f8cSWim Van Sebroeck } 620b7e04f8cSWim Van Sebroeck 621b7e04f8cSWim Van Sebroeck ret = register_reboot_notifier(&wdt_notifier); 622b7e04f8cSWim Van Sebroeck if (ret) { 623*27c766aaSJoe Perches pr_err("cannot register reboot notifier (err=%d)\n", ret); 624b7e04f8cSWim Van Sebroeck goto outirq; 625b7e04f8cSWim Van Sebroeck } 626b7e04f8cSWim Van Sebroeck 62704bedfa5SAlan Cox if (type == 501) { 628b7e04f8cSWim Van Sebroeck ret = misc_register(&temp_miscdev); 629b7e04f8cSWim Van Sebroeck if (ret) { 630*27c766aaSJoe Perches pr_err("cannot register miscdev on minor=%d (err=%d)\n", 631*27c766aaSJoe Perches TEMP_MINOR, ret); 632b7e04f8cSWim Van Sebroeck goto outrbt; 633b7e04f8cSWim Van Sebroeck } 63404bedfa5SAlan Cox } 635b7e04f8cSWim Van Sebroeck 636b7e04f8cSWim Van Sebroeck ret = misc_register(&wdt_miscdev); 637b7e04f8cSWim Van Sebroeck if (ret) { 638*27c766aaSJoe Perches pr_err("cannot register miscdev on minor=%d (err=%d)\n", 639b7e04f8cSWim Van Sebroeck WATCHDOG_MINOR, ret); 640b7e04f8cSWim Van Sebroeck goto outmisc; 641b7e04f8cSWim Van Sebroeck } 642b7e04f8cSWim Van Sebroeck 643*27c766aaSJoe Perches pr_info("WDT500/501-P driver 0.10 at 0x%04x (Interrupt %d). heartbeat=%d sec (nowayout=%d)\n", 644b7e04f8cSWim Van Sebroeck io, irq, heartbeat, nowayout); 64504bedfa5SAlan Cox if (type == 501) 646*27c766aaSJoe Perches pr_info("Fan Tachometer is %s\n", 647*27c766aaSJoe Perches tachometer ? "Enabled" : "Disabled"); 64804bedfa5SAlan Cox return 0; 649b7e04f8cSWim Van Sebroeck 650b7e04f8cSWim Van Sebroeck outmisc: 65104bedfa5SAlan Cox if (type == 501) 652b7e04f8cSWim Van Sebroeck misc_deregister(&temp_miscdev); 653b7e04f8cSWim Van Sebroeck outrbt: 654b7e04f8cSWim Van Sebroeck unregister_reboot_notifier(&wdt_notifier); 655b7e04f8cSWim Van Sebroeck outirq: 656b7e04f8cSWim Van Sebroeck free_irq(irq, NULL); 657b7e04f8cSWim Van Sebroeck outreg: 658b7e04f8cSWim Van Sebroeck release_region(io, 8); 65904bedfa5SAlan Cox out: 66004bedfa5SAlan Cox return ret; 661b7e04f8cSWim Van Sebroeck } 662b7e04f8cSWim Van Sebroeck 663b7e04f8cSWim Van Sebroeck module_init(wdt_init); 664b7e04f8cSWim Van Sebroeck module_exit(wdt_exit); 665b7e04f8cSWim Van Sebroeck 666b7e04f8cSWim Van Sebroeck MODULE_AUTHOR("Alan Cox"); 667b7e04f8cSWim Van Sebroeck MODULE_DESCRIPTION("Driver for ISA ICS watchdog cards (WDT500/501)"); 668b7e04f8cSWim Van Sebroeck MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); 669b7e04f8cSWim Van Sebroeck MODULE_ALIAS_MISCDEV(TEMP_MINOR); 670b7e04f8cSWim Van Sebroeck MODULE_LICENSE("GPL"); 671