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author | Wim Van Sebroeck <wim@iguana.be> | 2007-08-17 08:38:02 (GMT) |
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committer | Wim Van Sebroeck <wim@iguana.be> | 2007-10-18 10:39:03 (GMT) |
commit | b7e04f8c61a46d742de23af5d7ca2b41b33e40ac (patch) | |
tree | c52a7ea568648e2d8ed0d423098b42298de2058b /drivers/watchdog/w83697hf_wdt.c | |
parent | d85714d81cc0408daddb68c10f7fd69eafe7c213 (diff) | |
download | linux-b7e04f8c61a46d742de23af5d7ca2b41b33e40ac.tar.xz |
mv watchdog tree under drivers
move watchdog tree from drivers/char/watchdog to drivers/watchdog.
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
Diffstat (limited to 'drivers/watchdog/w83697hf_wdt.c')
-rw-r--r-- | drivers/watchdog/w83697hf_wdt.c | 450 |
1 files changed, 450 insertions, 0 deletions
diff --git a/drivers/watchdog/w83697hf_wdt.c b/drivers/watchdog/w83697hf_wdt.c new file mode 100644 index 0000000..d9e821d --- /dev/null +++ b/drivers/watchdog/w83697hf_wdt.c @@ -0,0 +1,450 @@ +/* + * w83697hf/hg WDT driver + * + * (c) Copyright 2006 Samuel Tardieu <sam@rfc1149.net> + * (c) Copyright 2006 Marcus Junker <junker@anduras.de> + * + * Based on w83627hf_wdt.c which is based on advantechwdt.c + * which is based on wdt.c. + * Original copyright messages: + * + * (c) Copyright 2003 Pádraig Brady <P@draigBrady.com> + * + * (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 Marcus Junker nor ANDURAS AG admit liability nor provide + * warranty for any of this software. This material is provided + * "AS-IS" and at no charge. + */ + +#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 <linux/spinlock.h> + +#include <asm/io.h> +#include <asm/uaccess.h> +#include <asm/system.h> + +#define WATCHDOG_NAME "w83697hf/hg WDT" +#define PFX WATCHDOG_NAME ": " +#define WATCHDOG_TIMEOUT 60 /* 60 sec default timeout */ + +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_param(wdt_io, int, 0); +MODULE_PARM_DESC(wdt_io, "w83697hf/hg WDT io port (default 0x2e, 0 = autodetect)"); + +static int timeout = WATCHDOG_TIMEOUT; /* in seconds */ +module_param(timeout, int, 0); +MODULE_PARM_DESC(timeout, "Watchdog timeout in seconds. 1<= timeout <=255, 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) ")"); + +/* + * Kernel methods. + */ + +#define W83697HF_EFER (wdt_io+0) /* Extended Function Enable Register */ +#define W83697HF_EFIR (wdt_io+0) /* Extended Function Index Register (same as EFER) */ +#define W83697HF_EFDR (wdt_io+1) /* Extended Function Data Register */ + +static inline void +w83697hf_unlock(void) +{ + outb_p(0x87, W83697HF_EFER); /* Enter extended function mode */ + outb_p(0x87, W83697HF_EFER); /* Again according to manual */ +} + +static inline void +w83697hf_lock(void) +{ + outb_p(0xAA, W83697HF_EFER); /* Leave extended function mode */ +} + +/* + * The three functions w83697hf_get_reg(), w83697hf_set_reg() and + * w83697hf_write_timeout() must be called with the device unlocked. + */ + +static unsigned char +w83697hf_get_reg(unsigned char reg) +{ + outb_p(reg, W83697HF_EFIR); + return inb_p(W83697HF_EFDR); +} + +static void +w83697hf_set_reg(unsigned char reg, unsigned char data) +{ + outb_p(reg, W83697HF_EFIR); + outb_p(data, W83697HF_EFDR); +} + +static void +w83697hf_write_timeout(int timeout) +{ + w83697hf_set_reg(0xF4, timeout); /* Write Timeout counter to CRF4 */ +} + +static void +w83697hf_select_wdt(void) +{ + w83697hf_unlock(); + w83697hf_set_reg(0x07, 0x08); /* Switch to logic device 8 (GPIO2) */ +} + +static inline void +w83697hf_deselect_wdt(void) +{ + w83697hf_lock(); +} + +static void +w83697hf_init(void) +{ + unsigned char bbuf; + + w83697hf_select_wdt(); + + bbuf = w83697hf_get_reg(0x29); + bbuf &= ~0x60; + bbuf |= 0x20; + w83697hf_set_reg(0x29, bbuf); /* Set pin 119 to WDTO# mode (= CR29, WDT0) */ + + bbuf = w83697hf_get_reg(0xF3); + bbuf &= ~0x04; + w83697hf_set_reg(0xF3, bbuf); /* Count mode is seconds */ + + w83697hf_deselect_wdt(); +} + +static int +wdt_ping(void) +{ + spin_lock(&io_lock); + w83697hf_select_wdt(); + + w83697hf_write_timeout(timeout); + + w83697hf_deselect_wdt(); + spin_unlock(&io_lock); + return 0; +} + +static int +wdt_enable(void) +{ + spin_lock(&io_lock); + w83697hf_select_wdt(); + + w83697hf_write_timeout(timeout); + w83697hf_set_reg(0x30, 1); /* Enable timer */ + + w83697hf_deselect_wdt(); + spin_unlock(&io_lock); + return 0; +} + +static int +wdt_disable(void) +{ + spin_lock(&io_lock); + w83697hf_select_wdt(); + + w83697hf_set_reg(0x30, 0); /* Disable timer */ + w83697hf_write_timeout(0); + + w83697hf_deselect_wdt(); + spin_unlock(&io_lock); + 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 __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 = "W83697HF 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_enable(); + 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_enable(); + 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 const 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 +w83697hf_check_wdt(void) +{ + if (!request_region(wdt_io, 2, WATCHDOG_NAME)) { + printk (KERN_ERR PFX "I/O address 0x%x already in use\n", wdt_io); + return -EIO; + } + + printk (KERN_DEBUG PFX "Looking for watchdog at address 0x%x\n", wdt_io); + w83697hf_unlock(); + if (w83697hf_get_reg(0x20) == 0x60) { + printk (KERN_INFO PFX "watchdog found at address 0x%x\n", wdt_io); + w83697hf_lock(); + return 0; + } + w83697hf_lock(); /* Reprotect in case it was a compatible device */ + + printk (KERN_INFO PFX "watchdog not found at address 0x%x\n", wdt_io); + release_region(wdt_io, 2); + return -EIO; +} + +static int w83697hf_ioports[] = { 0x2e, 0x4e, 0x00 }; + +static int __init +wdt_init(void) +{ + int ret, i, found = 0; + + spin_lock_init(&io_lock); + + printk (KERN_INFO PFX "WDT driver for W83697HF/HG initializing\n"); + + if (wdt_io == 0) { + /* we will autodetect the W83697HF/HG watchdog */ + for (i = 0; ((!found) && (w83697hf_ioports[i] != 0)); i++) { + wdt_io = w83697hf_ioports[i]; + if (!w83697hf_check_wdt()) + found++; + } + } else { + if (!w83697hf_check_wdt()) + found++; + } + + if (!found) { + printk (KERN_ERR PFX "No W83697HF/HG could be found\n"); + ret = -EIO; + goto out; + } + + w83697hf_init(); + wdt_disable(); /* Disable watchdog until first use */ + + if (wdt_set_heartbeat(timeout)) { + wdt_set_heartbeat(WATCHDOG_TIMEOUT); + printk (KERN_INFO PFX "timeout value must be 1<=timeout<=255, using %d\n", + WATCHDOG_TIMEOUT); + } + + 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, 2); + goto out; +} + +static void __exit +wdt_exit(void) +{ + misc_deregister(&wdt_miscdev); + unregister_reboot_notifier(&wdt_notifier); + release_region(wdt_io, 2); +} + +module_init(wdt_init); +module_exit(wdt_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Marcus Junker <junker@anduras.de>, Samuel Tardieu <sam@rfc1149.net>"); +MODULE_DESCRIPTION("w83697hf/hg WDT driver"); +MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); |