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author | Jorge Boncompte [DTI2] <jorge@dti2.net> | 2007-11-19 15:09:21 +0100 |
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committer | Wim Van Sebroeck <wim@iguana.be> | 2007-11-19 21:25:41 +0000 |
commit | 38ff6fd2fa4959925cf217ccaebea90fabd8ce04 (patch) | |
tree | 2f6680a4810d3cbc6964409c7b1bed01b550bf95 /drivers/watchdog/it8712f_wdt.c | |
parent | 6027f661f8da653f084df80f4aade21359bcea35 (diff) | |
download | linux-stable-38ff6fd2fa4959925cf217ccaebea90fabd8ce04.tar.gz linux-stable-38ff6fd2fa4959925cf217ccaebea90fabd8ce04.tar.bz2 linux-stable-38ff6fd2fa4959925cf217ccaebea90fabd8ce04.zip |
[WATCHDOG] IT8212F watchdog driver
This patch adds support for the ITE Tech Inc. IT8712F EC-LPC Super I/O
chipset found on many Pentium III and AMD motherboards. Developed using code
from other watchdog drivers and the datasheet on ITE Tech homepage.
Signed-off-by: Jorge Boncompte <jorge@dti2.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Diffstat (limited to 'drivers/watchdog/it8712f_wdt.c')
-rw-r--r-- | drivers/watchdog/it8712f_wdt.c | 400 |
1 files changed, 400 insertions, 0 deletions
diff --git a/drivers/watchdog/it8712f_wdt.c b/drivers/watchdog/it8712f_wdt.c new file mode 100644 index 000000000000..6330fc02464e --- /dev/null +++ b/drivers/watchdog/it8712f_wdt.c @@ -0,0 +1,400 @@ +/* + * IT8712F "Smart Guardian" Watchdog support + * + * Copyright (c) 2006-2007 Jorge Boncompte - DTI2 <jorge@dti2.net> + * + * Based on info and code taken from: + * + * drivers/char/watchdog/scx200_wdt.c + * drivers/hwmon/it87.c + * IT8712F EC-LPC I/O Preliminary Specification 0.9.2.pdf + * + * 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(s) of this software shall not be held liable for damages + * of any nature resulting due to the use of this software. This + * software is provided AS-IS with no warranties. + */ + +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/init.h> +#include <linux/miscdevice.h> +#include <linux/watchdog.h> +#include <linux/notifier.h> +#include <linux/reboot.h> +#include <linux/fs.h> +#include <linux/pci.h> +#include <linux/spinlock.h> + +#include <asm/uaccess.h> +#include <asm/io.h> + +#define NAME "it8712f_wdt" + +MODULE_AUTHOR("Jorge Boncompte - DTI2 <jorge@dti2.net>"); +MODULE_DESCRIPTION("IT8712F Watchdog Driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); + +static int margin = 60; /* in seconds */ +module_param(margin, int, 0); +MODULE_PARM_DESC(margin, "Watchdog margin in seconds"); + +static int nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, int, 0); +MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close"); + +static struct semaphore it8712f_wdt_sem; +static unsigned expect_close; +static spinlock_t io_lock; + +/* Dog Food address - We use the game port address */ +static unsigned short address; + +#define REG 0x2e /* The register to read/write */ +#define VAL 0x2f /* The value to read/write */ + +#define LDN 0x07 /* Register: Logical device select */ +#define DEVID 0x20 /* Register: Device ID */ +#define DEVREV 0x22 /* Register: Device Revision */ +#define ACT_REG 0x30 /* LDN Register: Activation */ +#define BASE_REG 0x60 /* LDN Register: Base address */ + +#define IT8712F_DEVID 0x8712 + +#define LDN_GPIO 0x07 /* GPIO and Watch Dog Timer */ +#define LDN_GAME 0x09 /* Game Port */ + +#define WDT_CONTROL 0x71 /* WDT Register: Control */ +#define WDT_CONFIG 0x72 /* WDT Register: Configuration */ +#define WDT_TIMEOUT 0x73 /* WDT Register: Timeout Value */ + +#define WDT_RESET_GAME 0x10 +#define WDT_RESET_KBD 0x20 +#define WDT_RESET_MOUSE 0x40 +#define WDT_RESET_CIR 0x80 + +#define WDT_UNIT_SEC 0x80 /* If 0 in MINUTES */ + +#define WDT_OUT_PWROK 0x10 +#define WDT_OUT_KRST 0x40 + +static int +superio_inb(int reg) +{ + outb(reg, REG); + return inb(VAL); +} + +static void +superio_outb(int val, int reg) +{ + outb(reg, REG); + outb(val, VAL); +} + +static int +superio_inw(int reg) +{ + int val; + outb(reg++, REG); + val = inb(VAL) << 8; + outb(reg, REG); + val |= inb(VAL); + return val; +} + +static inline void +superio_select(int ldn) +{ + outb(LDN, REG); + outb(ldn, VAL); +} + +static inline void +superio_enter(void) +{ + spin_lock(&io_lock); + outb(0x87, REG); + outb(0x01, REG); + outb(0x55, REG); + outb(0x55, REG); +} + +static inline void +superio_exit(void) +{ + outb(0x02, REG); + outb(0x02, VAL); + spin_unlock(&io_lock); +} + +static inline void +it8712f_wdt_ping(void) +{ + inb(address); +} + +static void +it8712f_wdt_update_margin(void) +{ + int config = WDT_OUT_KRST | WDT_OUT_PWROK; + + printk(KERN_INFO NAME ": timer margin %d seconds\n", margin); + + /* The timeout register only has 8bits wide */ + if (margin < 256) + config |= WDT_UNIT_SEC; /* else UNIT are MINUTES */ + superio_outb(config, WDT_CONFIG); + + superio_outb((margin > 255) ? (margin / 60) : margin, WDT_TIMEOUT); +} + +static void +it8712f_wdt_enable(void) +{ + printk(KERN_DEBUG NAME ": enabling watchdog timer\n"); + superio_enter(); + superio_select(LDN_GPIO); + + superio_outb(WDT_RESET_GAME, WDT_CONTROL); + + it8712f_wdt_update_margin(); + + superio_exit(); + + it8712f_wdt_ping(); +} + +static void +it8712f_wdt_disable(void) +{ + printk(KERN_DEBUG NAME ": disabling watchdog timer\n"); + + superio_enter(); + superio_select(LDN_GPIO); + + superio_outb(0, WDT_CONFIG); + superio_outb(0, WDT_CONTROL); + superio_outb(0, WDT_TIMEOUT); + + superio_exit(); +} + +static int +it8712f_wdt_notify(struct notifier_block *this, + unsigned long code, void *unused) +{ + if (code == SYS_HALT || code == SYS_POWER_OFF) + if (!nowayout) + it8712f_wdt_disable(); + + return NOTIFY_DONE; +} + +static struct notifier_block it8712f_wdt_notifier = { + .notifier_call = it8712f_wdt_notify, +}; + +static ssize_t +it8712f_wdt_write(struct file *file, const char __user *data, + size_t len, loff_t *ppos) +{ + /* check for a magic close character */ + if (len) { + size_t i; + + it8712f_wdt_ping(); + + expect_close = 0; + for (i = 0; i < len; ++i) { + char c; + if (get_user(c, data+i)) + return -EFAULT; + if (c == 'V') + expect_close = 42; + } + } + + return len; +} + +static int +it8712f_wdt_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 = { + .identity = "IT8712F Watchdog", + .firmware_version = 1, + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, + }; + int new_margin; + + switch (cmd) { + default: + return -ENOTTY; + case WDIOC_GETSUPPORT: + if (copy_to_user(argp, &ident, sizeof(ident))) + return -EFAULT; + return 0; + case WDIOC_GETSTATUS: + case WDIOC_GETBOOTSTATUS: + return put_user(0, p); + case WDIOC_KEEPALIVE: + it8712f_wdt_ping(); + return 0; + case WDIOC_SETTIMEOUT: + if (get_user(new_margin, p)) + return -EFAULT; + if (new_margin < 1) + return -EINVAL; + margin = new_margin; + superio_enter(); + superio_select(LDN_GPIO); + + it8712f_wdt_update_margin(); + + superio_exit(); + it8712f_wdt_ping(); + case WDIOC_GETTIMEOUT: + if (put_user(margin, p)) + return -EFAULT; + return 0; + } +} + +static int +it8712f_wdt_open(struct inode *inode, struct file *file) +{ + /* only allow one at a time */ + if (down_trylock(&it8712f_wdt_sem)) + return -EBUSY; + it8712f_wdt_enable(); + + return nonseekable_open(inode, file); +} + +static int +it8712f_wdt_release(struct inode *inode, struct file *file) +{ + if (expect_close != 42) { + printk(KERN_WARNING NAME + ": watchdog device closed unexpectedly, will not" + " disable the watchdog timer\n"); + } else if (!nowayout) { + it8712f_wdt_disable(); + } + expect_close = 0; + up(&it8712f_wdt_sem); + + return 0; +} + +static struct file_operations it8712f_wdt_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .write = it8712f_wdt_write, + .ioctl = it8712f_wdt_ioctl, + .open = it8712f_wdt_open, + .release = it8712f_wdt_release, +}; + +static struct miscdevice it8712f_wdt_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &it8712f_wdt_fops, +}; + +static int __init +it8712f_wdt_find(unsigned short *address) +{ + int err = -ENODEV; + int chip_type; + + superio_enter(); + chip_type = superio_inw(DEVID); + if (chip_type != IT8712F_DEVID) + goto exit; + + superio_select(LDN_GAME); + superio_outb(1, ACT_REG); + if (!(superio_inb(ACT_REG) & 0x01)) { + printk(KERN_ERR NAME ": Device not activated, skipping\n"); + goto exit; + } + + *address = superio_inw(BASE_REG); + if (*address == 0) { + printk(KERN_ERR NAME ": Base address not set, skipping\n"); + goto exit; + } + + err = 0; + printk(KERN_DEBUG NAME ": Found IT%04xF chip revision %d - " + "using DogFood address 0x%x\n", + chip_type, superio_inb(DEVREV) & 0x0f, *address); + +exit: + superio_exit(); + return err; +} + +static int __init +it8712f_wdt_init(void) +{ + int err = 0; + + spin_lock_init(&io_lock); + + if (it8712f_wdt_find(&address)) + return -ENODEV; + + if (!request_region(address, 1, "IT8712F Watchdog")) { + printk(KERN_WARNING NAME ": watchdog I/O region busy\n"); + return -EBUSY; + } + + it8712f_wdt_disable(); + + sema_init(&it8712f_wdt_sem, 1); + + err = register_reboot_notifier(&it8712f_wdt_notifier); + if (err) { + printk(KERN_ERR NAME ": unable to register reboot notifier\n"); + goto out; + } + + err = misc_register(&it8712f_wdt_miscdev); + if (err) { + printk(KERN_ERR NAME + ": cannot register miscdev on minor=%d (err=%d)\n", + WATCHDOG_MINOR, err); + goto reboot_out; + } + + return 0; + + +reboot_out: + unregister_reboot_notifier(&it8712f_wdt_notifier); +out: + release_region(address, 1); + return err; +} + +static void __exit +it8712f_wdt_exit(void) +{ + misc_deregister(&it8712f_wdt_miscdev); + unregister_reboot_notifier(&it8712f_wdt_notifier); + release_region(address, 1); +} + +module_init(it8712f_wdt_init); +module_exit(it8712f_wdt_exit); |