diff options
Diffstat (limited to 'drivers/char/watchdog/sbc60xxwdt.c')
-rw-r--r-- | drivers/char/watchdog/sbc60xxwdt.c | 400 |
1 files changed, 0 insertions, 400 deletions
diff --git a/drivers/char/watchdog/sbc60xxwdt.c b/drivers/char/watchdog/sbc60xxwdt.c deleted file mode 100644 index e4f3cb6090b..00000000000 --- a/drivers/char/watchdog/sbc60xxwdt.c +++ /dev/null @@ -1,400 +0,0 @@ -/* - * 60xx Single Board Computer Watchdog Timer driver for Linux 2.2.x - * - * Based on acquirewdt.c by Alan Cox. - * - * 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. - * - * The author does NOT admit liability nor provide warranty for - * any of this software. This material is provided "AS-IS" in - * the hope that it may be useful for others. - * - * (c) Copyright 2000 Jakob Oestergaard <jakob@unthought.net> - * - * 12/4 - 2000 [Initial revision] - * 25/4 - 2000 Added /dev/watchdog support - * 09/5 - 2001 [smj@oro.net] fixed fop_write to "return 1" on success - * 12/4 - 2002 [rob@osinvestor.com] eliminate fop_read - * fix possible wdt_is_open race - * add CONFIG_WATCHDOG_NOWAYOUT support - * remove lock_kernel/unlock_kernel pairs - * added KERN_* to printk's - * got rid of extraneous comments - * changed watchdog_info to correctly reflect what the driver offers - * added WDIOC_GETSTATUS, WDIOC_GETBOOTSTATUS, WDIOC_SETTIMEOUT, - * WDIOC_GETTIMEOUT, and WDIOC_SETOPTIONS ioctls - * 09/8 - 2003 [wim@iguana.be] cleanup of trailing spaces - * use module_param - * made timeout (the emulated heartbeat) a module_param - * made the keepalive ping an internal subroutine - * made wdt_stop and wdt_start module params - * added extra printk's for startup problems - * added MODULE_AUTHOR and MODULE_DESCRIPTION info - * - * - * This WDT driver is different from the other Linux WDT - * drivers in the following ways: - * *) The driver will ping the watchdog by itself, because this - * particular WDT has a very short timeout (one second) and it - * would be insane to count on any userspace daemon always - * getting scheduled within that time frame. - * - */ - -#include <linux/module.h> -#include <linux/moduleparam.h> -#include <linux/types.h> -#include <linux/timer.h> -#include <linux/jiffies.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 OUR_NAME "sbc60xxwdt" -#define PFX OUR_NAME ": " - -/* - * You must set these - The driver cannot probe for the settings - */ - -static int wdt_stop = 0x45; -module_param(wdt_stop, int, 0); -MODULE_PARM_DESC(wdt_stop, "SBC60xx WDT 'stop' io port (default 0x45)"); - -static int wdt_start = 0x443; -module_param(wdt_start, int, 0); -MODULE_PARM_DESC(wdt_start, "SBC60xx WDT 'start' io port (default 0x443)"); - -/* - * The 60xx board can use watchdog timeout values from one second - * to several minutes. The default is one second, so if we reset - * the watchdog every ~250ms we should be safe. - */ - -#define WDT_INTERVAL (HZ/4+1) - -/* - * We must not require too good response from the userspace daemon. - * Here we require the userspace daemon to send us a heartbeat - * char to /dev/watchdog every 30 seconds. - * If the daemon pulses us every 25 seconds, we can still afford - * a 5 second scheduling delay on the (high priority) daemon. That - * should be sufficient for a box under any load. - */ - -#define WATCHDOG_TIMEOUT 30 /* 30 sec default timeout */ -static int timeout = WATCHDOG_TIMEOUT; /* in seconds, will be multiplied by HZ to get seconds to wait for a ping */ -module_param(timeout, int, 0); -MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. (1<=timeout<=3600, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) ")"); - -static int nowayout = WATCHDOG_NOWAYOUT; -module_param(nowayout, int, 0); -MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(WATCHDOG_NOWAYOUT) ")"); - -static void wdt_timer_ping(unsigned long); -static DEFINE_TIMER(timer, wdt_timer_ping, 0, 0); -static unsigned long next_heartbeat; -static unsigned long wdt_is_open; -static char wdt_expect_close; - -/* - * Whack the dog - */ - -static void wdt_timer_ping(unsigned long data) -{ - /* If we got a heartbeat pulse within the WDT_US_INTERVAL - * we agree to ping the WDT - */ - if(time_before(jiffies, next_heartbeat)) - { - /* Ping the WDT by reading from wdt_start */ - inb_p(wdt_start); - /* Re-set the timer interval */ - mod_timer(&timer, jiffies + WDT_INTERVAL); - } else { - printk(KERN_WARNING PFX "Heartbeat lost! Will not ping the watchdog\n"); - } -} - -/* - * Utility routines - */ - -static void wdt_startup(void) -{ - next_heartbeat = jiffies + (timeout * HZ); - - /* Start the timer */ - mod_timer(&timer, jiffies + WDT_INTERVAL); - printk(KERN_INFO PFX "Watchdog timer is now enabled.\n"); -} - -static void wdt_turnoff(void) -{ - /* Stop the timer */ - del_timer(&timer); - inb_p(wdt_stop); - printk(KERN_INFO PFX "Watchdog timer is now disabled...\n"); -} - -static void wdt_keepalive(void) -{ - /* user land ping */ - next_heartbeat = jiffies + (timeout * HZ); -} - -/* - * /dev/watchdog handling - */ - -static ssize_t fop_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 ofs; - - /* note: just in case someone wrote the magic character - * five months ago... */ - wdt_expect_close = 0; - - /* scan to see whether or not we got the magic character */ - for(ofs = 0; ofs != count; ofs++) - { - char c; - if(get_user(c, buf+ofs)) - return -EFAULT; - if(c == 'V') - wdt_expect_close = 42; - } - } - - /* Well, anyhow someone wrote to us, we should return that favour */ - wdt_keepalive(); - } - return count; -} - -static int fop_open(struct inode * inode, struct file * file) -{ - /* Just in case we're already talking to someone... */ - if(test_and_set_bit(0, &wdt_is_open)) - return -EBUSY; - - if (nowayout) - __module_get(THIS_MODULE); - - /* Good, fire up the show */ - wdt_startup(); - return nonseekable_open(inode, file); -} - -static int fop_close(struct inode * inode, struct file * file) -{ - if(wdt_expect_close == 42) - wdt_turnoff(); - else { - del_timer(&timer); - printk(KERN_CRIT PFX "device file closed unexpectedly. Will not stop the WDT!\n"); - } - clear_bit(0, &wdt_is_open); - wdt_expect_close = 0; - return 0; -} - -static int fop_ioctl(struct inode *inode, struct file *file, unsigned int cmd, - unsigned long arg) -{ - void __user *argp = (void __user *)arg; - int __user *p = argp; - static struct watchdog_info ident= - { - .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, - .firmware_version = 1, - .identity = "SBC60xx", - }; - - switch(cmd) - { - default: - return -ENOTTY; - 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: - wdt_keepalive(); - return 0; - case WDIOC_SETOPTIONS: - { - int new_options, retval = -EINVAL; - - if(get_user(new_options, p)) - return -EFAULT; - - if(new_options & WDIOS_DISABLECARD) { - wdt_turnoff(); - retval = 0; - } - - if(new_options & WDIOS_ENABLECARD) { - wdt_startup(); - retval = 0; - } - - return retval; - } - case WDIOC_SETTIMEOUT: - { - int new_timeout; - - if(get_user(new_timeout, p)) - return -EFAULT; - - if(new_timeout < 1 || new_timeout > 3600) /* arbitrary upper limit */ - return -EINVAL; - - timeout = new_timeout; - wdt_keepalive(); - /* Fall through */ - } - case WDIOC_GETTIMEOUT: - return put_user(timeout, p); - } -} - -static const struct file_operations wdt_fops = { - .owner = THIS_MODULE, - .llseek = no_llseek, - .write = fop_write, - .open = fop_open, - .release = fop_close, - .ioctl = fop_ioctl, -}; - -static struct miscdevice wdt_miscdev = { - .minor = WATCHDOG_MINOR, - .name = "watchdog", - .fops = &wdt_fops, -}; - -/* - * 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_turnoff(); - return NOTIFY_DONE; -} - -/* - * 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 void __exit sbc60xxwdt_unload(void) -{ - wdt_turnoff(); - - /* Deregister */ - misc_deregister(&wdt_miscdev); - - unregister_reboot_notifier(&wdt_notifier); - if ((wdt_stop != 0x45) && (wdt_stop != wdt_start)) - release_region(wdt_stop,1); - release_region(wdt_start,1); -} - -static int __init sbc60xxwdt_init(void) -{ - int rc = -EBUSY; - - if(timeout < 1 || timeout > 3600) /* arbitrary upper limit */ - { - timeout = WATCHDOG_TIMEOUT; - printk(KERN_INFO PFX "timeout value must be 1<=x<=3600, using %d\n", - timeout); - } - - if (!request_region(wdt_start, 1, "SBC 60XX WDT")) - { - printk(KERN_ERR PFX "I/O address 0x%04x already in use\n", - wdt_start); - rc = -EIO; - goto err_out; - } - - /* We cannot reserve 0x45 - the kernel already has! */ - if ((wdt_stop != 0x45) && (wdt_stop != wdt_start)) - { - if (!request_region(wdt_stop, 1, "SBC 60XX WDT")) - { - printk(KERN_ERR PFX "I/O address 0x%04x already in use\n", - wdt_stop); - rc = -EIO; - goto err_out_region1; - } - } - - rc = misc_register(&wdt_miscdev); - if (rc) - { - printk(KERN_ERR PFX "cannot register miscdev on minor=%d (err=%d)\n", - wdt_miscdev.minor, rc); - goto err_out_region2; - } - - rc = register_reboot_notifier(&wdt_notifier); - if (rc) - { - printk(KERN_ERR PFX "cannot register reboot notifier (err=%d)\n", - rc); - goto err_out_miscdev; - } - - printk(KERN_INFO PFX "WDT driver for 60XX single board computer initialised. timeout=%d sec (nowayout=%d)\n", - timeout, nowayout); - - return 0; - -err_out_miscdev: - misc_deregister(&wdt_miscdev); -err_out_region2: - if ((wdt_stop != 0x45) && (wdt_stop != wdt_start)) - release_region(wdt_stop,1); -err_out_region1: - release_region(wdt_start,1); -err_out: - return rc; -} - -module_init(sbc60xxwdt_init); -module_exit(sbc60xxwdt_unload); - -MODULE_AUTHOR("Jakob Oestergaard <jakob@unthought.net>"); -MODULE_DESCRIPTION("60xx Single Board Computer Watchdog Timer driver"); -MODULE_LICENSE("GPL"); -MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |