| /* |
| * w83627hf WDT driver |
| * |
| * backported from w83627hf_wdt.c kernel 2.6.20.1 |
| * (c) Copyright 2007 Orpak Systems Ltd. (Tal Kelrich <tal@orpak.com>) |
| * |
| * (c) Copyright 2003 Padraig Brady <P@draigBrady.com> |
| * |
| * Based on advantechwdt.c which is based on wdt.c. |
| * Original copyright messages: |
| * |
| * (c) Copyright 2000-2001 Marek Michalkiewicz <marekm@linux.org.pl> |
| * |
| * (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> |
| */ |
| |
| #include <linux/module.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 <linux/spinlock.h> |
| #include <linux/proc_fs.h> |
| |
| #include <asm/io.h> |
| #include <asm/uaccess.h> |
| #include <asm/system.h> |
| #include <asm/page.h> |
| |
| #define WATCHDOG_NAME "W83627HF WDT" |
| #define PFX WATCHDOG_NAME ": " |
| #define WATCHDOG_TIMEOUT 120 /* 120 sec default timeout */ |
| |
| #ifdef CONFIG_WATCHDOG_NOWAYOUT |
| #define WATCHDOG_NOWAYOUT 1 |
| #else |
| #define WATCHDOG_NOWAYOUT 0 |
| #endif |
| |
| static unsigned long wdt_is_open; |
| static char expect_close; |
| static spinlock_t io_lock; |
| |
| /* You must set this - there is no sane way to probe for this board. */ |
| static int wdt_io = 0x2E; |
| MODULE_PARM(wdt_io, "i"); |
| MODULE_PARM_DESC(wdt_io, "w83627hf WDT io port (default 0x2E)"); |
| |
| static int timeout = WATCHDOG_TIMEOUT; /* in seconds */ |
| MODULE_PARM(timeout, "i"); |
| MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1<= timeout <=255, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) "."); |
| |
| static int nowayout = WATCHDOG_NOWAYOUT; |
| MODULE_PARM(nowayout, "i"); |
| MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default=" __MODULE_STRING(CONFIG_WATCHDOG_NOWAYOUT)")"); |
| |
| /* |
| * Kernel methods. |
| */ |
| |
| #define WDT_EFER (wdt_io+0) /* Extended Function Enable Registers */ |
| #define WDT_EFIR (wdt_io+0) /* Extended Function Index Register (same as EFER) */ |
| #define WDT_EFDR (WDT_EFIR+1) /* Extended Function Data Register */ |
| |
| /* Non standard proc bits, added by request, wanted some feedback */ |
| |
| static void |
| w83627hf_select_wd_register(void) |
| { |
| outb_p(0x87, WDT_EFER); /* Enter extended function mode */ |
| outb_p(0x87, WDT_EFER); /* Again according to manual */ |
| |
| outb_p(0x07, WDT_EFER); /* point to logical device number reg */ |
| outb_p(0x08, WDT_EFDR); /* select logical device 8 (GPIO2) */ |
| outb_p(0x30, WDT_EFER); /* select CR30 */ |
| outb_p(0x01, WDT_EFDR); /* set bit 0 to activate GPIO2 */ |
| } |
| |
| static void |
| w83627hf_unselect_wd_register(void) |
| { |
| outb_p(0xAA, WDT_EFER); /* Leave extended function mode */ |
| } |
| |
| /* tyan motherboards seem to set F5 to 0x4C ? |
| * So explicitly init to appropriate value. */ |
| static void |
| w83627hf_init(void) |
| { |
| unsigned char t; |
| |
| w83627hf_select_wd_register(); |
| |
| outb_p(0xF6, WDT_EFER); /* Select CRF6 */ |
| outb_p(0, WDT_EFDR); /* set to 0 initially */ |
| outb_p(0xF5, WDT_EFER); /* Select CRF5 */ |
| t=inb_p(WDT_EFDR); /* read CRF5 */ |
| t&=~0x0C; /* set second mode & disable keyboard turning off watchdog */ |
| outb_p(t, WDT_EFDR); /* Write back to CRF5 */ |
| |
| w83627hf_unselect_wd_register(); |
| } |
| |
| static int wdt_readproc(char *page, char **start, off_t off, int count, |
| int *eof, void *data) |
| { |
| int len; |
| unsigned char remaining; |
| unsigned char fired; |
| spin_lock(&io_lock); |
| w83627hf_select_wd_register(); |
| outb_p(0xF6, WDT_EFIR);/* get current timer val */ |
| remaining=inb_p(WDT_EFDR); |
| outb_p(0xF7, WDT_EFIR); |
| fired=inb_p(WDT_EFDR); |
| /* clear that bit (bit 4) */ |
| outb_p(fired&(~0x10),WDT_EFDR); |
| w83627hf_unselect_wd_register(); |
| spin_unlock(&io_lock); |
| fired=(fired&0x10)!=0; |
| len=snprintf(page,PAGE_SIZE, |
| "W83627HF WDT\n" |
| "active=%d\n" |
| "iobase=%04X\n" |
| "nowayout=%d\n" |
| "timeout=%d\n" |
| "remaining=%d\n" |
| "fired=%d\n", |
| wdt_is_open,wdt_io,nowayout,timeout,remaining,fired); |
| *eof=1; |
| return len; |
| } |
| |
| static void |
| wdt_ctrl(int timeout) |
| { |
| spin_lock(&io_lock); |
| |
| w83627hf_select_wd_register(); |
| |
| outb_p(0xF6, WDT_EFER); /* Select CRF6 */ |
| outb_p(timeout, WDT_EFDR); /* Write Timeout counter to CRF6 */ |
| |
| w83627hf_unselect_wd_register(); |
| |
| spin_unlock(&io_lock); |
| } |
| |
| static int |
| wdt_ping(void) |
| { |
| wdt_ctrl(timeout); |
| return 0; |
| } |
| |
| static int |
| wdt_disable(void) |
| { |
| wdt_ctrl(0); |
| return 0; |
| } |
| |
| static int |
| wdt_set_heartbeat(int t) |
| { |
| if ((t < 1) || (t > 255)) |
| return -EINVAL; |
| |
| timeout = t; |
| return 0; |
| } |
| |
| static ssize_t |
| wdt_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) { |
| if (!nowayout) { |
| size_t i; |
| |
| expect_close = 0; |
| |
| for (i = 0; i != count; i++) { |
| char c; |
| if (get_user(c, buf+i)) |
| return -EFAULT; |
| if (c == 'V') |
| expect_close = 42; |
| } |
| } |
| wdt_ping(); |
| } |
| return count; |
| } |
| |
| static int |
| wdt_ioctl(struct inode *inode, struct file *file, unsigned int cmd, |
| unsigned long arg) |
| { |
| void *argp = (void *)arg; |
| int *p = argp; |
| int new_timeout; |
| static struct watchdog_info ident = { |
| .options = WDIOF_KEEPALIVEPING | WDIOF_SETTIMEOUT | WDIOF_MAGICCLOSE, |
| .firmware_version = 1, |
| .identity = "W83627HF WDT", |
| }; |
| |
| switch (cmd) { |
| case WDIOC_GETSUPPORT: |
| if (copy_to_user(argp, &ident, sizeof(ident))) |
| return -EFAULT; |
| break; |
| |
| case WDIOC_GETSTATUS: |
| case WDIOC_GETBOOTSTATUS: |
| return put_user(0, p); |
| |
| case WDIOC_KEEPALIVE: |
| wdt_ping(); |
| break; |
| |
| case WDIOC_SETTIMEOUT: |
| if (get_user(new_timeout, p)) |
| return -EFAULT; |
| if (wdt_set_heartbeat(new_timeout)) |
| return -EINVAL; |
| wdt_ping(); |
| /* Fall */ |
| |
| case WDIOC_GETTIMEOUT: |
| return put_user(timeout, p); |
| |
| case WDIOC_SETOPTIONS: |
| { |
| int options, retval = -EINVAL; |
| |
| if (get_user(options, p)) |
| return -EFAULT; |
| |
| if (options & WDIOS_DISABLECARD) { |
| wdt_disable(); |
| retval = 0; |
| } |
| |
| if (options & WDIOS_ENABLECARD) { |
| wdt_ping(); |
| retval = 0; |
| } |
| |
| return retval; |
| } |
| |
| default: |
| return -ENOTTY; |
| } |
| return 0; |
| } |
| |
| static int |
| wdt_open(struct inode *inode, struct file *file) |
| { |
| if (test_and_set_bit(0, &wdt_is_open)) |
| return -EBUSY; |
| /* |
| * Activate |
| */ |
| |
| wdt_ping(); |
| return 0; |
| } |
| |
| static int |
| wdt_close(struct inode *inode, struct file *file) |
| { |
| if (expect_close == 42) { |
| wdt_disable(); |
| } else { |
| printk(KERN_CRIT PFX "Unexpected close, not stopping watchdog!\n"); |
| wdt_ping(); |
| } |
| expect_close = 0; |
| clear_bit(0, &wdt_is_open); |
| return 0; |
| } |
| |
| /* |
| * 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) { |
| /* Turn the WDT off */ |
| wdt_disable(); |
| } |
| return NOTIFY_DONE; |
| } |
| |
| /* |
| * Kernel Interfaces |
| */ |
| |
| static const struct file_operations wdt_fops = { |
| .owner = THIS_MODULE, |
| .write = wdt_write, |
| .ioctl = wdt_ioctl, |
| .open = wdt_open, |
| .release = wdt_close, |
| }; |
| |
| static struct miscdevice wdt_miscdev = { |
| .minor = WATCHDOG_MINOR, |
| .name = "watchdog", |
| .fops = &wdt_fops, |
| }; |
| |
| /* |
| * 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 int __init |
| wdt_init(void) |
| { |
| int ret = -EBUSY; |
| |
| spin_lock_init(&io_lock); |
| |
| printk(KERN_INFO "WDT driver for the Winbond(TM) W83627HF Super I/O chip initialising.\n"); |
| |
| if (wdt_set_heartbeat(timeout)) { |
| wdt_set_heartbeat(WATCHDOG_TIMEOUT); |
| printk (KERN_INFO PFX "timeout value must be 1<=timeout<=63, using %d\n", |
| WATCHDOG_TIMEOUT); |
| } |
| /* on the board I was working on, wdt_io consistently coincided with things already |
| * being used, hence the continuing here. |
| * there's probably a better solution to this */ |
| if (!request_region(wdt_io, 1, WATCHDOG_NAME)) { |
| printk (KERN_WARNING PFX "I/O address 0x%04x already in use, continuing anyway\n", |
| wdt_io); |
| } |
| if(!create_proc_read_entry("watchdog",0,NULL,&wdt_readproc,NULL)) |
| goto unreg_regions; |
| |
| w83627hf_init(); |
| |
| ret = register_reboot_notifier(&wdt_notifier); |
| if (ret != 0) { |
| printk (KERN_ERR PFX "cannot register reboot notifier (err=%d)\n", |
| ret); |
| goto unreg_proc; |
| } |
| |
| ret = misc_register(&wdt_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. timeout=%d sec (nowayout=%d)\n", |
| timeout, nowayout); |
| |
| out: |
| return ret; |
| unreg_reboot: |
| unregister_reboot_notifier(&wdt_notifier); |
| unreg_proc: |
| remove_proc_entry("watchdog",NULL); |
| unreg_regions: |
| release_region(wdt_io, 1); |
| goto out; |
| } |
| |
| static void __exit |
| wdt_exit(void) |
| { |
| remove_proc_entry("watchdog",NULL); |
| misc_deregister(&wdt_miscdev); |
| unregister_reboot_notifier(&wdt_notifier); |
| release_region(wdt_io,1); |
| /* we might not have gotten it... is this safe? */ |
| } |
| |
| module_init(wdt_init); |
| module_exit(wdt_exit); |
| |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Padraig Brady <P@draigBrady.com>"); |
| MODULE_DESCRIPTION("w83627hf WDT driver"); |