/* * MixCom Watchdog: A Simple Hardware Watchdog Device * Based on Softdog driver by Alan Cox and PC Watchdog driver by Ken Hollis * * Author: Gergely Madarasz * * Copyright (c) 1999 ITConsult-Pro Co. * * 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. * * Version 0.1 (99/04/15): * - first version * * Version 0.2 (99/06/16): * - added kernel timer watchdog ping after close * since the hardware does not support watchdog shutdown * * Version 0.3 (99/06/21): * - added WDIOC_GETSTATUS and WDIOC_GETSUPPORT ioctl calls * * Version 0.3.1 (99/06/22): * - allow module removal while internal timer is active, * print warning about probable reset * * Version 0.4 (99/11/15): * - support for one more type board * * Version 0.5 (2001/12/14) Matt Domsch * - added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT * */ #define VERSION "0.5" #include #include #include #include #include #include #include #include #include #include #include #include #include static int mixcomwd_ioports[] = { 0x180, 0x280, 0x380, 0x000 }; #define MIXCOM_WATCHDOG_OFFSET 0xc10 #define MIXCOM_ID 0x11 #define FLASHCOM_WATCHDOG_OFFSET 0x4 #define FLASHCOM_ID 0x18 static unsigned long mixcomwd_opened; /* long req'd for setbit --RR */ static int watchdog_port; static int mixcomwd_timer_alive; static DEFINE_TIMER(mixcomwd_timer, NULL, 0, 0); static char expect_close; static int nowayout = WATCHDOG_NOWAYOUT; module_param(nowayout, int, 0); MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)"); static void mixcomwd_ping(void) { outb_p(55,watchdog_port); return; } static void mixcomwd_timerfun(unsigned long d) { mixcomwd_ping(); mod_timer(&mixcomwd_timer,jiffies+ 5*HZ); } /* * Allow only one person to hold it open */ static int mixcomwd_open(struct inode *inode, struct file *file) { if(test_and_set_bit(0,&mixcomwd_opened)) { return -EBUSY; } mixcomwd_ping(); if (nowayout) { /* * fops_get() code via open() has already done * a try_module_get() so it is safe to do the * __module_get(). */ __module_get(THIS_MODULE); } else { if(mixcomwd_timer_alive) { del_timer(&mixcomwd_timer); mixcomwd_timer_alive=0; } } return nonseekable_open(inode, file); } static int mixcomwd_release(struct inode *inode, struct file *file) { if (expect_close == 42) { if(mixcomwd_timer_alive) { printk(KERN_ERR "mixcomwd: release called while internal timer alive"); return -EBUSY; } init_timer(&mixcomwd_timer); mixcomwd_timer.expires=jiffies + 5 * HZ; mixcomwd_timer.function=mixcomwd_timerfun; mixcomwd_timer.data=0; mixcomwd_timer_alive=1; add_timer(&mixcomwd_timer); } else { printk(KERN_CRIT "mixcomwd: WDT device closed unexpectedly. WDT will not stop!\n"); } clear_bit(0,&mixcomwd_opened); expect_close=0; return 0; } static ssize_t mixcomwd_write(struct file *file, const char __user *data, size_t len, loff_t *ppos) { if(len) { if (!nowayout) { size_t i; /* In case it was set long ago */ expect_close = 0; for (i = 0; i != len; i++) { char c; if (get_user(c, data + i)) return -EFAULT; if (c == 'V') expect_close = 42; } } mixcomwd_ping(); } return len; } static int mixcomwd_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg) { void __user *argp = (void __user *)arg; int __user *p = argp; int status; static struct watchdog_info ident = { .options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, .firmware_version = 1, .identity = "MixCOM watchdog", }; switch(cmd) { case WDIOC_GETSTATUS: status=mixcomwd_opened; if (!nowayout) { status|=mixcomwd_timer_alive; } if (copy_to_user(p, &status, sizeof(int))) { return -EFAULT; } break; case WDIOC_GETSUPPORT: if (copy_to_user(argp, &ident, sizeof(ident))) { return -EFAULT; } break; case WDIOC_KEEPALIVE: mixcomwd_ping(); break; default: return -ENOTTY; } return 0; } static const struct file_operations mixcomwd_fops= { .owner = THIS_MODULE, .llseek = no_llseek, .write = mixcomwd_write, .ioctl = mixcomwd_ioctl, .open = mixcomwd_open, .release = mixcomwd_release, }; static struct miscdevice mixcomwd_miscdev= { .minor = WATCHDOG_MINOR, .name = "watchdog", .fops = &mixcomwd_fops, }; static int __init mixcomwd_checkcard(int port) { int id; port += MIXCOM_WATCHDOG_OFFSET; if (!request_region(port, 1, "MixCOM watchdog")) { return 0; } id=inb_p(port) & 0x3f; if(id!=MIXCOM_ID) { release_region(port, 1); return 0; } return port; } static int __init flashcom_checkcard(int port) { int id; port += FLASHCOM_WATCHDOG_OFFSET; if (!request_region(port, 1, "MixCOM watchdog")) { return 0; } id=inb_p(port); if(id!=FLASHCOM_ID) { release_region(port, 1); return 0; } return port; } static int __init mixcomwd_init(void) { int i; int ret; int found=0; for (i = 0; !found && mixcomwd_ioports[i] != 0; i++) { watchdog_port = mixcomwd_checkcard(mixcomwd_ioports[i]); if (watchdog_port) { found = 1; } } /* The FlashCOM card can be set up at 0x300 -> 0x378, in 0x8 jumps */ for (i = 0x300; !found && i < 0x380; i+=0x8) { watchdog_port = flashcom_checkcard(i); if (watchdog_port) { found = 1; } } if (!found) { printk("mixcomwd: No card detected, or port not available.\n"); return -ENODEV; } ret = misc_register(&mixcomwd_miscdev); if (ret) { release_region(watchdog_port, 1); return ret; } printk(KERN_INFO "MixCOM watchdog driver v%s, watchdog port at 0x%3x\n",VERSION,watchdog_port); return 0; } static void __exit mixcomwd_exit(void) { if (!nowayout) { if(mixcomwd_timer_alive) { printk(KERN_WARNING "mixcomwd: I quit now, hardware will" " probably reboot!\n"); del_timer(&mixcomwd_timer); mixcomwd_timer_alive=0; } } release_region(watchdog_port,1); misc_deregister(&mixcomwd_miscdev); } module_init(mixcomwd_init); module_exit(mixcomwd_exit); MODULE_AUTHOR("Gergely Madarasz "); MODULE_DESCRIPTION("MixCom Watchdog driver"); MODULE_LICENSE("GPL"); MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR);