diff options
Diffstat (limited to 'drivers/char/watchdog/acquirewdt.c')
| -rw-r--r-- | drivers/char/watchdog/acquirewdt.c | 327 |
1 files changed, 0 insertions, 327 deletions
diff --git a/drivers/char/watchdog/acquirewdt.c b/drivers/char/watchdog/acquirewdt.c deleted file mode 100644 index 7289f4af93d..00000000000 --- a/drivers/char/watchdog/acquirewdt.c +++ /dev/null @@ -1,327 +0,0 @@ -/* - * Acquire Single Board Computer Watchdog Timer driver - * - * Based on wdt.c. Original copyright messages: - * - * (c) Copyright 1996 Alan Cox <alan@redhat.com>, All Rights Reserved. - * http://www.redhat.com - * - * 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 <alan@redhat.com> - * - * 14-Dec-2001 Matt Domsch <Matt_Domsch@dell.com> - * Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT - * Can't add timeout - driver doesn't allow changing value - */ - -/* - * Theory of Operation: - * The Watch-Dog Timer is provided to ensure that standalone - * Systems can always recover from catastrophic conditions that - * caused the CPU to crash. This condition may have occured by - * external EMI or a software bug. When the CPU stops working - * correctly, hardware on the board will either perform a hardware - * reset (cold boot) or a non-maskable interrupt (NMI) to bring the - * system back to a known state. - * - * The Watch-Dog Timer is controlled by two I/O Ports. - * 443 hex - Read - Enable or refresh the Watch-Dog Timer - * 043 hex - Read - Disable the Watch-Dog Timer - * - * To enable the Watch-Dog Timer, a read from I/O port 443h must - * be performed. This will enable and activate the countdown timer - * which will eventually time out and either reset the CPU or cause - * an NMI depending on the setting of a jumper. To ensure that this - * reset condition does not occur, the Watch-Dog Timer must be - * periodically refreshed by reading the same I/O port 443h. - * The Watch-Dog Timer is disabled by reading I/O port 043h. - * - * The Watch-Dog Timer Time-Out Period is set via jumpers. - * It can be 1, 2, 10, 20, 110 or 220 seconds. - */ - -#include <linux/module.h> -#include <linux/moduleparam.h> -#include <linux/types.h> -#include <linux/miscdevice.h> -#include <linux/watchdog.h> -#include <linux/fs.h> -#include <linux/ioport.h> -#include <linux/notifier.h> -#include <linux/reboot.h> -#include <linux/init.h> - -#include <asm/io.h> -#include <asm/uaccess.h> -#include <asm/system.h> - -#define WATCHDOG_NAME "Acquire WDT" -#define PFX WATCHDOG_NAME ": " -#define WATCHDOG_HEARTBEAT 0 /* There is no way to see what the correct time-out period is */ - -static unsigned long acq_is_open; -static char expect_close; - -/* - * You must set these - there is no sane way to probe for this board. - */ - -static int wdt_stop = 0x43; -module_param(wdt_stop, int, 0); -MODULE_PARM_DESC(wdt_stop, "Acquire WDT 'stop' io port (default 0x43)"); - -static int wdt_start = 0x443; -module_param(wdt_start, int, 0); -MODULE_PARM_DESC(wdt_start, "Acquire WDT 'start' io port (default 0x443)"); - -static int nowayout = WATCHDOG_NOWAYOUT; -module_param(nowayout, int, 0); -MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)"); - -/* - * Kernel methods. - */ - -static void acq_keepalive(void) -{ - /* Write a watchdog value */ - inb_p(wdt_start); -} - -static void acq_stop(void) -{ - /* Turn the card off */ - inb_p(wdt_stop); -} - -/* - * /dev/watchdog handling. - */ - -static ssize_t acq_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) -{ - /* See if we got the magic character 'V' and reload the timer */ - if(count) { - if (!nowayout) { - size_t i; - - /* note: just in case someone wrote the magic character - * five months ago... */ - expect_close = 0; - - /* scan to see whether or not we got the magic character */ - for (i = 0; i != count; i++) { - char c; - if (get_user(c, buf + i)) - return -EFAULT; - if (c == 'V') - expect_close = 42; - } - } - - /* Well, anyhow someone wrote to us, we should return that favour */ - acq_keepalive(); - } - return count; -} - -static int acq_ioctl(struct inode *inode, struct file *file, unsigned int cmd, - unsigned long arg) -{ - int options, retval = -EINVAL; - void __user *argp = (void __user *)arg; - int __user *p = argp; - static struct watchdog_info ident = - { - .options = WDIOF_KEEPALIVEPING | WDIOF_MAGICCLOSE, - .firmware_version = 1, - .identity = "Acquire WDT", - }; - - switch(cmd) - { - case WDIOC_GETSUPPORT: - return copy_to_user(argp, &ident, sizeof(ident)) ? -EFAULT : 0; - - case WDIOC_GETSTATUS: - case WDIOC_GETBOOTSTATUS: - return put_user(0, p); - - case WDIOC_KEEPALIVE: - acq_keepalive(); - return 0; - - case WDIOC_GETTIMEOUT: - return put_user(WATCHDOG_HEARTBEAT, p); - - case WDIOC_SETOPTIONS: - { - if (get_user(options, p)) - return -EFAULT; - - if (options & WDIOS_DISABLECARD) - { - acq_stop(); - retval = 0; - } - - if (options & WDIOS_ENABLECARD) - { - acq_keepalive(); - retval = 0; - } - - return retval; - } - - default: - return -ENOIOCTLCMD; - } -} - -static int acq_open(struct inode *inode, struct file *file) -{ - if (test_and_set_bit(0, &acq_is_open)) - return -EBUSY; - - if (nowayout) - __module_get(THIS_MODULE); - - /* Activate */ - acq_keepalive(); - return nonseekable_open(inode, file); -} - -static int acq_close(struct inode *inode, struct file *file) -{ - if (expect_close == 42) { - acq_stop(); - } else { - printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n"); - acq_keepalive(); - } - clear_bit(0, &acq_is_open); - expect_close = 0; - return 0; -} - -/* - * Notifier for system down - */ - -static int acq_notify_sys(struct notifier_block *this, unsigned long code, - void *unused) -{ - if(code==SYS_DOWN || code==SYS_HALT) { - /* Turn the WDT off */ - acq_stop(); - } - return NOTIFY_DONE; -} - -/* - * Kernel Interfaces - */ - -static struct file_operations acq_fops = { - .owner = THIS_MODULE, - .llseek = no_llseek, - .write = acq_write, - .ioctl = acq_ioctl, - .open = acq_open, - .release = acq_close, -}; - -static struct miscdevice acq_miscdev= -{ - .minor = WATCHDOG_MINOR, - .name = "watchdog", - .fops = &acq_fops, -}; - -/* - * The WDT card needs to learn about soft shutdowns in order to - * turn the timebomb registers off. - */ - -static struct notifier_block acq_notifier = -{ - .notifier_call = acq_notify_sys, -}; - -static int __init acq_init(void) -{ - int ret; - - printk(KERN_INFO "WDT driver for Acquire single board computer initialising.\n"); - - if (wdt_stop != wdt_start) { - if (!request_region(wdt_stop, 1, WATCHDOG_NAME)) { - printk (KERN_ERR PFX "I/O address 0x%04x already in use\n", - wdt_stop); - ret = -EIO; - goto out; - } - } - - if (!request_region(wdt_start, 1, WATCHDOG_NAME)) { - printk (KERN_ERR PFX "I/O address 0x%04x already in use\n", - wdt_start); - ret = -EIO; - goto unreg_stop; - } - - ret = register_reboot_notifier(&acq_notifier); - if (ret != 0) { - printk (KERN_ERR PFX "cannot register reboot notifier (err=%d)\n", - ret); - goto unreg_regions; - } - - ret = misc_register(&acq_miscdev); - if (ret != 0) { - printk (KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n", - WATCHDOG_MINOR, ret); - goto unreg_reboot; - } - - printk (KERN_INFO PFX "initialized. (nowayout=%d)\n", - nowayout); - - return 0; - -unreg_reboot: - unregister_reboot_notifier(&acq_notifier); -unreg_regions: - release_region(wdt_start, 1); -unreg_stop: - if (wdt_stop != wdt_start) - release_region(wdt_stop, 1); -out: - return ret; -} - -static void __exit acq_exit(void) -{ - misc_deregister(&acq_miscdev); - unregister_reboot_notifier(&acq_notifier); - if(wdt_stop != wdt_start) - release_region(wdt_stop,1); - release_region(wdt_start,1); -} - -module_init(acq_init); -module_exit(acq_exit); - -MODULE_AUTHOR("David Woodhouse"); -MODULE_DESCRIPTION("Acquire Inc. Single Board Computer Watchdog Timer driver"); -MODULE_LICENSE("GPL"); -MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |