diff options
Diffstat (limited to 'drivers/char/watchdog/w83627hf_wdt.c')
| -rw-r--r-- | drivers/char/watchdog/w83627hf_wdt.c | 362 |
1 files changed, 362 insertions, 0 deletions
diff --git a/drivers/char/watchdog/w83627hf_wdt.c b/drivers/char/watchdog/w83627hf_wdt.c new file mode 100644 index 000000000000..813c97038f84 --- /dev/null +++ b/drivers/char/watchdog/w83627hf_wdt.c @@ -0,0 +1,362 @@ +/* + * w83627hf WDT driver + * + * (c) Copyright 2003 Pádraig 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/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 "w83627hf WDT" +#define PFX WATCHDOG_NAME ": " +#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */ + +static unsigned long wdt_is_open; +static char expect_close; + +/* You must set this - there is no sane way to probe for this board. */ +static int wdt_io = 0x2E; +module_param(wdt_io, int, 0); +MODULE_PARM_DESC(wdt_io, "w83627hf WDT io port (default 0x2E)"); + +static int timeout = WATCHDOG_TIMEOUT; /* in seconds */ +module_param(timeout, int, 0); +MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1<= timeout <=63, default=" __MODULE_STRING(WATCHDOG_TIMEOUT) "."); + +#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)"); + +/* + * 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 */ + +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(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 void +wdt_ctrl(int timeout) +{ + 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(); +} + +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 > 63)) + return -EINVAL; + + timeout = t; + return 0; +} + +static ssize_t +wdt_write(struct file *file, const char __user *buf, size_t count, loff_t *ppos) +{ + 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 __user *argp = (void __user *)arg; + int __user *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 -ENOIOCTLCMD; + } + 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 nonseekable_open(inode, file); +} + +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 struct file_operations wdt_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .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; + + 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); + } + + if (!request_region(wdt_io, 1, WATCHDOG_NAME)) { + printk (KERN_ERR PFX "I/O address 0x%04x already in use\n", + wdt_io); + ret = -EIO; + goto out; + } + + 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_regions; + } + + 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_regions: + release_region(wdt_io, 1); + goto out; +} + +static void __exit +wdt_exit(void) +{ + misc_deregister(&wdt_miscdev); + unregister_reboot_notifier(&wdt_notifier); + release_region(wdt_io,1); +} + +module_init(wdt_init); +module_exit(wdt_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Pádraig Brady <P@draigBrady.com>"); +MODULE_DESCRIPTION("w38627hf WDT driver"); +MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |