| /* |
| * Wdt977 0.02: A Watchdog Device for Netwinder W83977AF chip |
| * |
| * (c) Copyright 1998 Rebel.com (Woody Suwalski <woody@netwinder.org>) |
| * |
| * ----------------------- |
| * |
| * 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. |
| * |
| * ----------------------- |
| * 14-Dec-2001 Matt Domsch <Matt_Domsch@dell.com> |
| * Added nowayout module option to override CONFIG_WATCHDOG_NOWAYOUT |
| * 19-Dec-2001 Woody Suwalski: Netwinder fixes, ioctl interface |
| * 06-Jan-2002 Woody Suwalski: For compatibility, convert all timeouts |
| * from minutes to seconds. |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/config.h> |
| #include <linux/types.h> |
| #include <linux/kernel.h> |
| #include <linux/fs.h> |
| #include <linux/miscdevice.h> |
| #include <linux/init.h> |
| #include <linux/smp_lock.h> |
| #include <linux/watchdog.h> |
| |
| #include <asm/io.h> |
| #include <asm/system.h> |
| #include <asm/mach-types.h> |
| #include <asm/uaccess.h> |
| |
| #define WATCHDOG_MINOR 130 |
| |
| #define DEFAULT_TIMEOUT 1 /* default timeout = 1 minute */ |
| |
| static int timeout = DEFAULT_TIMEOUT*60; /* TO in seconds from user */ |
| static int timeoutM = DEFAULT_TIMEOUT; /* timeout in minutes */ |
| static int timer_alive; |
| static int testmode; |
| |
| MODULE_PARM(timeout, "i"); |
| MODULE_PARM_DESC(timeout,"Watchdog timeout in seconds (60..15300), default=60"); |
| MODULE_PARM(testmode, "i"); |
| MODULE_PARM_DESC(testmode,"Watchdog testmode (1 = no reboot), default=0"); |
| |
| #ifdef CONFIG_WATCHDOG_NOWAYOUT |
| static int nowayout = 1; |
| #else |
| static int nowayout = 0; |
| #endif |
| |
| MODULE_PARM(nowayout,"i"); |
| MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=CONFIG_WATCHDOG_NOWAYOUT)"); |
| |
| |
| /* This is kicking the watchdog by simply re-writing the timeout to reg. 0xF2 */ |
| int kick_wdog(void) |
| { |
| /* |
| * Refresh the timer. |
| */ |
| |
| /* unlock the SuperIO chip */ |
| outb(0x87,0x370); |
| outb(0x87,0x370); |
| |
| /* select device Aux2 (device=8) and kicks watchdog reg F2 */ |
| /* F2 has the timeout in minutes */ |
| |
| outb(0x07,0x370); |
| outb(0x08,0x371); |
| outb(0xF2,0x370); |
| outb(timeoutM,0x371); |
| |
| /* lock the SuperIO chip */ |
| outb(0xAA,0x370); |
| |
| return 0; |
| } |
| |
| |
| /* |
| * Allow only one person to hold it open |
| */ |
| |
| static int wdt977_open(struct inode *inode, struct file *file) |
| { |
| |
| if(timer_alive) |
| return -EBUSY; |
| |
| /* convert seconds to minutes, rounding up */ |
| timeoutM = timeout + 59; |
| timeoutM /= 60; |
| |
| if (nowayout) |
| { |
| MOD_INC_USE_COUNT; |
| |
| /* do not permit disabling the watchdog by writing 0 to reg. 0xF2 */ |
| if (!timeoutM) timeoutM = DEFAULT_TIMEOUT; |
| } |
| timer_alive++; |
| |
| if (machine_is_netwinder()) |
| { |
| /* we have a hw bug somewhere, so each 977 minute is actually only 30sec |
| * this limits the max timeout to half of device max of 255 minutes... |
| */ |
| timeoutM += timeoutM; |
| } |
| |
| /* max timeout value = 255 minutes (0xFF). Write 0 to disable WatchDog. */ |
| if (timeoutM > 255) timeoutM = 255; |
| |
| /* convert seconds to minutes */ |
| printk(KERN_INFO "Wdt977 Watchdog activated: timeout = %d sec, nowayout = %i, testmode = %i.\n", |
| machine_is_netwinder() ? (timeoutM>>1)*60 : timeoutM*60, |
| nowayout, testmode); |
| |
| /* unlock the SuperIO chip */ |
| outb(0x87,0x370); |
| outb(0x87,0x370); |
| |
| /* select device Aux2 (device=8) and set watchdog regs F2, F3 and F4 |
| * F2 has the timeout in minutes |
| * F3 could be set to the POWER LED blink (with GP17 set to PowerLed) |
| * at timeout, and to reset timer on kbd/mouse activity (not impl.) |
| * F4 is used to just clear the TIMEOUT'ed state (bit 0) |
| */ |
| outb(0x07,0x370); |
| outb(0x08,0x371); |
| outb(0xF2,0x370); |
| outb(timeoutM,0x371); |
| outb(0xF3,0x370); |
| outb(0x00,0x371); /* another setting is 0E for kbd/mouse/LED */ |
| outb(0xF4,0x370); |
| outb(0x00,0x371); |
| |
| /* at last select device Aux1 (dev=7) and set GP16 as a watchdog output */ |
| /* in test mode watch the bit 1 on F4 to indicate "triggered" */ |
| if (!testmode) |
| { |
| outb(0x07,0x370); |
| outb(0x07,0x371); |
| outb(0xE6,0x370); |
| outb(0x08,0x371); |
| } |
| |
| /* lock the SuperIO chip */ |
| outb(0xAA,0x370); |
| |
| return 0; |
| } |
| |
| static int wdt977_release(struct inode *inode, struct file *file) |
| { |
| /* |
| * Shut off the timer. |
| * Lock it in if it's a module and we set nowayout |
| */ |
| if (!nowayout) |
| { |
| lock_kernel(); |
| |
| /* unlock the SuperIO chip */ |
| outb(0x87,0x370); |
| outb(0x87,0x370); |
| |
| /* select device Aux2 (device=8) and set watchdog regs F2,F3 and F4 |
| * F3 is reset to its default state |
| * F4 can clear the TIMEOUT'ed state (bit 0) - back to default |
| * We can not use GP17 as a PowerLed, as we use its usage as a RedLed |
| */ |
| outb(0x07,0x370); |
| outb(0x08,0x371); |
| outb(0xF2,0x370); |
| outb(0xFF,0x371); |
| outb(0xF3,0x370); |
| outb(0x00,0x371); |
| outb(0xF4,0x370); |
| outb(0x00,0x371); |
| outb(0xF2,0x370); |
| outb(0x00,0x371); |
| |
| /* at last select device Aux1 (dev=7) and set GP16 as a watchdog output */ |
| outb(0x07,0x370); |
| outb(0x07,0x371); |
| outb(0xE6,0x370); |
| outb(0x08,0x371); |
| |
| /* lock the SuperIO chip */ |
| outb(0xAA,0x370); |
| |
| timer_alive=0; |
| unlock_kernel(); |
| |
| printk(KERN_INFO "Wdt977 Watchdog: shutdown\n"); |
| } |
| return 0; |
| } |
| |
| |
| /* |
| * wdt977_write: |
| * @file: file handle to the watchdog |
| * @buf: buffer to write (unused as data does not matter here |
| * @count: count of bytes |
| * @ppos: pointer to the position to write. No seeks allowed |
| * |
| * A write to a watchdog device is defined as a keepalive signal. Any |
| * write of data will do, as we we don't define content meaning. |
| */ |
| |
| static ssize_t wdt977_write(struct file *file, const char *buf, size_t count, loff_t *ppos) |
| { |
| /* Can't seek (pwrite) on this device */ |
| if (ppos != &file->f_pos) |
| return -ESPIPE; |
| |
| if(count) |
| { |
| kick_wdog(); |
| return 1; |
| } |
| return 0; |
| } |
| |
| /* |
| * wdt977_ioctl: |
| * @inode: inode of the device |
| * @file: file handle to the device |
| * @cmd: watchdog command |
| * @arg: argument pointer |
| * |
| * The watchdog API defines a common set of functions for all watchdogs |
| * according to their available features. |
| */ |
| |
| static int wdt977_ioctl(struct inode *inode, struct file *file, |
| unsigned int cmd, unsigned long arg) |
| { |
| static struct watchdog_info ident = { |
| identity : "Winbond 83977" |
| }; |
| |
| int temp; |
| |
| switch(cmd) |
| { |
| default: |
| return -ENOTTY; |
| |
| case WDIOC_GETSUPPORT: |
| return copy_to_user((struct watchdog_info *)arg, &ident, |
| sizeof(ident)) ? -EFAULT : 0; |
| |
| case WDIOC_GETBOOTSTATUS: |
| return put_user(0, (int *) arg); |
| |
| case WDIOC_GETSTATUS: |
| /* unlock the SuperIO chip */ |
| outb(0x87,0x370); |
| outb(0x87,0x370); |
| |
| /* select device Aux2 (device=8) and read watchdog reg F4 */ |
| outb(0x07,0x370); |
| outb(0x08,0x371); |
| outb(0xF4,0x370); |
| temp = inb(0x371); |
| |
| /* lock the SuperIO chip */ |
| outb(0xAA,0x370); |
| |
| /* return info if "expired" in test mode */ |
| return put_user(temp & 1, (int *) arg); |
| |
| case WDIOC_KEEPALIVE: |
| kick_wdog(); |
| return 0; |
| |
| case WDIOC_SETTIMEOUT: |
| if (copy_from_user(&temp, (int *) arg, sizeof(int))) |
| return -EFAULT; |
| |
| /* convert seconds to minutes, rounding up */ |
| temp += 59; |
| temp /= 60; |
| |
| /* we have a hw bug somewhere, so each 977 minute is actually only 30sec |
| * this limits the max timeout to half of device max of 255 minutes... |
| */ |
| if (machine_is_netwinder()) |
| { |
| temp += temp; |
| } |
| |
| /* Sanity check */ |
| if (temp < 0 || temp > 255) |
| return -EINVAL; |
| |
| if (!temp && nowayout) |
| return -EINVAL; |
| |
| timeoutM = temp; |
| kick_wdog(); |
| return 0; |
| } |
| } |
| |
| |
| static struct file_operations wdt977_fops= |
| { |
| owner: THIS_MODULE, |
| write: wdt977_write, |
| ioctl: wdt977_ioctl, |
| open: wdt977_open, |
| release: wdt977_release, |
| }; |
| |
| static struct miscdevice wdt977_miscdev= |
| { |
| WATCHDOG_MINOR, |
| "watchdog", |
| &wdt977_fops |
| }; |
| |
| static int __init nwwatchdog_init(void) |
| { |
| if (!machine_is_netwinder()) |
| return -ENODEV; |
| |
| misc_register(&wdt977_miscdev); |
| printk(KERN_INFO "Wdt977 Watchdog sleeping.\n"); |
| return 0; |
| } |
| |
| static void __exit nwwatchdog_exit(void) |
| { |
| misc_deregister(&wdt977_miscdev); |
| } |
| |
| EXPORT_NO_SYMBOLS; |
| |
| module_init(nwwatchdog_init); |
| module_exit(nwwatchdog_exit); |
| |
| MODULE_LICENSE("GPL"); |