diff options
Diffstat (limited to 'drivers/char/watchdog/mixcomwd.c')
| -rw-r--r-- | drivers/char/watchdog/mixcomwd.c | 306 |
1 files changed, 306 insertions, 0 deletions
diff --git a/drivers/char/watchdog/mixcomwd.c b/drivers/char/watchdog/mixcomwd.c new file mode 100644 index 000000000000..3143e4a07535 --- /dev/null +++ b/drivers/char/watchdog/mixcomwd.c @@ -0,0 +1,306 @@ +/* + * MixCom Watchdog: A Simple Hardware Watchdog Device + * Based on Softdog driver by Alan Cox and PC Watchdog driver by Ken Hollis + * + * Author: Gergely Madarasz <gorgo@itc.hu> + * + * Copyright (c) 1999 ITConsult-Pro Co. <info@itc.hu> + * + * 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 <Matt_Domsch@dell.com> + * - added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT + * + */ + +#define VERSION "0.5" + +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/config.h> +#include <linux/types.h> +#include <linux/miscdevice.h> +#include <linux/ioport.h> +#include <linux/watchdog.h> +#include <linux/fs.h> +#include <linux/reboot.h> +#include <linux/init.h> +#include <asm/uaccess.h> +#include <asm/io.h> + +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 struct timer_list mixcomwd_timer = TIMER_INITIALIZER(NULL, 0, 0); +static char expect_close; + +#ifdef CONFIG_WATCHDOG_NOWAYOUT +static int nowayout = 1; +#else +static int nowayout = 0; +#endif + +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 -ENOIOCTLCMD; + } + return 0; +} + +static 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 <gorgo@itc.hu>"); +MODULE_DESCRIPTION("MixCom Watchdog driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |