diff options
Diffstat (limited to 'drivers/watchdog/f71808e_wdt.c')
| -rw-r--r-- | drivers/watchdog/f71808e_wdt.c | 768 |
1 files changed, 768 insertions, 0 deletions
diff --git a/drivers/watchdog/f71808e_wdt.c b/drivers/watchdog/f71808e_wdt.c new file mode 100644 index 000000000000..7e5c266cda48 --- /dev/null +++ b/drivers/watchdog/f71808e_wdt.c @@ -0,0 +1,768 @@ +/*************************************************************************** + * Copyright (C) 2006 by Hans Edgington <hans@edgington.nl> * + * Copyright (C) 2007-2009 Hans de Goede <hdegoede@redhat.com> * + * Copyright (C) 2010 Giel van Schijndel <me@mortis.eu> * + * * + * 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. * + * * + * This program is distributed in the hope that it will be useful, * + * but WITHOUT ANY WARRANTY; without even the implied warranty of * + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * + * GNU General Public License for more details. * + * * + * You should have received a copy of the GNU General Public License * + * along with this program; if not, write to the * + * Free Software Foundation, Inc., * + * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. * + ***************************************************************************/ + +#include <linux/err.h> +#include <linux/fs.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/ioport.h> +#include <linux/miscdevice.h> +#include <linux/module.h> +#include <linux/mutex.h> +#include <linux/notifier.h> +#include <linux/reboot.h> +#include <linux/uaccess.h> +#include <linux/watchdog.h> + +#define DRVNAME "f71808e_wdt" + +#define SIO_F71808FG_LD_WDT 0x07 /* Watchdog timer logical device */ +#define SIO_UNLOCK_KEY 0x87 /* Key to enable Super-I/O */ +#define SIO_LOCK_KEY 0xAA /* Key to diasble Super-I/O */ + +#define SIO_REG_LDSEL 0x07 /* Logical device select */ +#define SIO_REG_DEVID 0x20 /* Device ID (2 bytes) */ +#define SIO_REG_DEVREV 0x22 /* Device revision */ +#define SIO_REG_MANID 0x23 /* Fintek ID (2 bytes) */ +#define SIO_REG_ENABLE 0x30 /* Logical device enable */ +#define SIO_REG_ADDR 0x60 /* Logical device address (2 bytes) */ + +#define SIO_FINTEK_ID 0x1934 /* Manufacturers ID */ +#define SIO_F71808_ID 0x0901 /* Chipset ID */ +#define SIO_F71858_ID 0x0507 /* Chipset ID */ +#define SIO_F71862_ID 0x0601 /* Chipset ID */ +#define SIO_F71882_ID 0x0541 /* Chipset ID */ +#define SIO_F71889_ID 0x0723 /* Chipset ID */ + +#define F71882FG_REG_START 0x01 + +#define F71808FG_REG_WDO_CONF 0xf0 +#define F71808FG_REG_WDT_CONF 0xf5 +#define F71808FG_REG_WD_TIME 0xf6 + +#define F71808FG_FLAG_WDOUT_EN 7 + +#define F71808FG_FLAG_WDTMOUT_STS 5 +#define F71808FG_FLAG_WD_EN 5 +#define F71808FG_FLAG_WD_PULSE 4 +#define F71808FG_FLAG_WD_UNIT 3 + +/* Default values */ +#define WATCHDOG_TIMEOUT 60 /* 1 minute default timeout */ +#define WATCHDOG_MAX_TIMEOUT (60 * 255) +#define WATCHDOG_PULSE_WIDTH 125 /* 125 ms, default pulse width for + watchdog signal */ + +static unsigned short force_id; +module_param(force_id, ushort, 0); +MODULE_PARM_DESC(force_id, "Override the detected device ID"); + +static const int max_timeout = WATCHDOG_MAX_TIMEOUT; +static int timeout = 60; /* default timeout in seconds */ +module_param(timeout, int, 0); +MODULE_PARM_DESC(timeout, + "Watchdog timeout in seconds. 1<= timeout <=" + __MODULE_STRING(WATCHDOG_MAX_TIMEOUT) " (default=" + __MODULE_STRING(WATCHDOG_TIMEOUT) ")"); + +static unsigned int pulse_width = WATCHDOG_PULSE_WIDTH; +module_param(pulse_width, uint, 0); +MODULE_PARM_DESC(pulse_width, + "Watchdog signal pulse width. 0(=level), 1 ms, 25 ms, 125 ms or 5000 ms" + " (default=" __MODULE_STRING(WATCHDOG_PULSE_WIDTH) ")"); + +static int nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, 0444); +MODULE_PARM_DESC(nowayout, "Disable watchdog shutdown on close"); + +static unsigned int start_withtimeout; +module_param(start_withtimeout, uint, 0); +MODULE_PARM_DESC(start_withtimeout, "Start watchdog timer on module load with" + " given initial timeout. Zero (default) disables this feature."); + +enum chips { f71808fg, f71858fg, f71862fg, f71882fg, f71889fg }; + +static const char *f71808e_names[] = { + "f71808fg", + "f71858fg", + "f71862fg", + "f71882fg", + "f71889fg", +}; + +/* Super-I/O Function prototypes */ +static inline int superio_inb(int base, int reg); +static inline int superio_inw(int base, int reg); +static inline void superio_outb(int base, int reg, u8 val); +static inline void superio_set_bit(int base, int reg, int bit); +static inline void superio_clear_bit(int base, int reg, int bit); +static inline int superio_enter(int base); +static inline void superio_select(int base, int ld); +static inline void superio_exit(int base); + +struct watchdog_data { + unsigned short sioaddr; + enum chips type; + unsigned long opened; + struct mutex lock; + char expect_close; + struct watchdog_info ident; + + unsigned short timeout; + u8 timer_val; /* content for the wd_time register */ + char minutes_mode; + u8 pulse_val; /* pulse width flag */ + char pulse_mode; /* enable pulse output mode? */ + char caused_reboot; /* last reboot was by the watchdog */ +}; + +static struct watchdog_data watchdog = { + .lock = __MUTEX_INITIALIZER(watchdog.lock), +}; + +/* Super I/O functions */ +static inline int superio_inb(int base, int reg) +{ + outb(reg, base); + return inb(base + 1); +} + +static int superio_inw(int base, int reg) +{ + int val; + val = superio_inb(base, reg) << 8; + val |= superio_inb(base, reg + 1); + return val; +} + +static inline void superio_outb(int base, int reg, u8 val) +{ + outb(reg, base); + outb(val, base + 1); +} + +static inline void superio_set_bit(int base, int reg, int bit) +{ + unsigned long val = superio_inb(base, reg); + __set_bit(bit, &val); + superio_outb(base, reg, val); +} + +static inline void superio_clear_bit(int base, int reg, int bit) +{ + unsigned long val = superio_inb(base, reg); + __clear_bit(bit, &val); + superio_outb(base, reg, val); +} + +static inline int superio_enter(int base) +{ + /* Don't step on other drivers' I/O space by accident */ + if (!request_muxed_region(base, 2, DRVNAME)) { + printk(KERN_ERR DRVNAME ": I/O address 0x%04x already in use\n", + (int)base); + return -EBUSY; + } + + /* according to the datasheet the key must be send twice! */ + outb(SIO_UNLOCK_KEY, base); + outb(SIO_UNLOCK_KEY, base); + + return 0; +} + +static inline void superio_select(int base, int ld) +{ + outb(SIO_REG_LDSEL, base); + outb(ld, base + 1); +} + +static inline void superio_exit(int base) +{ + outb(SIO_LOCK_KEY, base); + release_region(base, 2); +} + +static int watchdog_set_timeout(int timeout) +{ + if (timeout <= 0 + || timeout > max_timeout) { + printk(KERN_ERR DRVNAME ": watchdog timeout out of range\n"); + return -EINVAL; + } + + mutex_lock(&watchdog.lock); + + watchdog.timeout = timeout; + if (timeout > 0xff) { + watchdog.timer_val = DIV_ROUND_UP(timeout, 60); + watchdog.minutes_mode = true; + } else { + watchdog.timer_val = timeout; + watchdog.minutes_mode = false; + } + + mutex_unlock(&watchdog.lock); + + return 0; +} + +static int watchdog_set_pulse_width(unsigned int pw) +{ + int err = 0; + + mutex_lock(&watchdog.lock); + + if (pw <= 1) { + watchdog.pulse_val = 0; + } else if (pw <= 25) { + watchdog.pulse_val = 1; + } else if (pw <= 125) { + watchdog.pulse_val = 2; + } else if (pw <= 5000) { + watchdog.pulse_val = 3; + } else { + printk(KERN_ERR DRVNAME ": pulse width out of range\n"); + err = -EINVAL; + goto exit_unlock; + } + + watchdog.pulse_mode = pw; + +exit_unlock: + mutex_unlock(&watchdog.lock); + return err; +} + +static int watchdog_keepalive(void) +{ + int err = 0; + + mutex_lock(&watchdog.lock); + err = superio_enter(watchdog.sioaddr); + if (err) + goto exit_unlock; + superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT); + + if (watchdog.minutes_mode) + /* select minutes for timer units */ + superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF, + F71808FG_FLAG_WD_UNIT); + else + /* select seconds for timer units */ + superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF, + F71808FG_FLAG_WD_UNIT); + + /* Set timer value */ + superio_outb(watchdog.sioaddr, F71808FG_REG_WD_TIME, + watchdog.timer_val); + + superio_exit(watchdog.sioaddr); + +exit_unlock: + mutex_unlock(&watchdog.lock); + return err; +} + +static int watchdog_start(void) +{ + /* Make sure we don't die as soon as the watchdog is enabled below */ + int err = watchdog_keepalive(); + if (err) + return err; + + mutex_lock(&watchdog.lock); + err = superio_enter(watchdog.sioaddr); + if (err) + goto exit_unlock; + superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT); + + /* Watchdog pin configuration */ + switch (watchdog.type) { + case f71808fg: + /* Set pin 21 to GPIO23/WDTRST#, then to WDTRST# */ + superio_clear_bit(watchdog.sioaddr, 0x2a, 3); + superio_clear_bit(watchdog.sioaddr, 0x2b, 3); + break; + + case f71882fg: + /* Set pin 56 to WDTRST# */ + superio_set_bit(watchdog.sioaddr, 0x29, 1); + break; + + default: + /* + * 'default' label to shut up the compiler and catch + * programmer errors + */ + err = -ENODEV; + goto exit_superio; + } + + superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT); + superio_set_bit(watchdog.sioaddr, SIO_REG_ENABLE, 0); + superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDO_CONF, + F71808FG_FLAG_WDOUT_EN); + + superio_set_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF, + F71808FG_FLAG_WD_EN); + + if (watchdog.pulse_mode) { + /* Select "pulse" output mode with given duration */ + u8 wdt_conf = superio_inb(watchdog.sioaddr, + F71808FG_REG_WDT_CONF); + + /* Set WD_PSWIDTH bits (1:0) */ + wdt_conf = (wdt_conf & 0xfc) | (watchdog.pulse_val & 0x03); + /* Set WD_PULSE to "pulse" mode */ + wdt_conf |= BIT(F71808FG_FLAG_WD_PULSE); + + superio_outb(watchdog.sioaddr, F71808FG_REG_WDT_CONF, + wdt_conf); + } else { + /* Select "level" output mode */ + superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF, + F71808FG_FLAG_WD_PULSE); + } + +exit_superio: + superio_exit(watchdog.sioaddr); +exit_unlock: + mutex_unlock(&watchdog.lock); + + return err; +} + +static int watchdog_stop(void) +{ + int err = 0; + + mutex_lock(&watchdog.lock); + err = superio_enter(watchdog.sioaddr); + if (err) + goto exit_unlock; + superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT); + + superio_clear_bit(watchdog.sioaddr, F71808FG_REG_WDT_CONF, + F71808FG_FLAG_WD_EN); + + superio_exit(watchdog.sioaddr); + +exit_unlock: + mutex_unlock(&watchdog.lock); + + return err; +} + +static int watchdog_get_status(void) +{ + int status = 0; + + mutex_lock(&watchdog.lock); + status = (watchdog.caused_reboot) ? WDIOF_CARDRESET : 0; + mutex_unlock(&watchdog.lock); + + return status; +} + +static bool watchdog_is_running(void) +{ + /* + * if we fail to determine the watchdog's status assume it to be + * running to be on the safe side + */ + bool is_running = true; + + mutex_lock(&watchdog.lock); + if (superio_enter(watchdog.sioaddr)) + goto exit_unlock; + superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT); + + is_running = (superio_inb(watchdog.sioaddr, SIO_REG_ENABLE) & BIT(0)) + && (superio_inb(watchdog.sioaddr, F71808FG_REG_WDT_CONF) + & F71808FG_FLAG_WD_EN); + + superio_exit(watchdog.sioaddr); + +exit_unlock: + mutex_unlock(&watchdog.lock); + return is_running; +} + +/* /dev/watchdog api */ + +static int watchdog_open(struct inode *inode, struct file *file) +{ + int err; + + /* If the watchdog is alive we don't need to start it again */ + if (test_and_set_bit(0, &watchdog.opened)) + return -EBUSY; + + err = watchdog_start(); + if (err) { + clear_bit(0, &watchdog.opened); + return err; + } + + if (nowayout) + __module_get(THIS_MODULE); + + watchdog.expect_close = 0; + return nonseekable_open(inode, file); +} + +static int watchdog_release(struct inode *inode, struct file *file) +{ + clear_bit(0, &watchdog.opened); + + if (!watchdog.expect_close) { + watchdog_keepalive(); + printk(KERN_CRIT DRVNAME + ": Unexpected close, not stopping watchdog!\n"); + } else if (!nowayout) { + watchdog_stop(); + } + return 0; +} + +/* + * watchdog_write: + * @file: file handle to the watchdog + * @buf: buffer to write + * @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 watchdog_write(struct file *file, const char __user *buf, + size_t count, loff_t *ppos) +{ + if (count) { + if (!nowayout) { + size_t i; + + /* In case it was set long ago */ + bool expect_close = false; + + for (i = 0; i != count; i++) { + char c; + if (get_user(c, buf + i)) + return -EFAULT; + expect_close = (c == 'V'); + } + + /* Properly order writes across fork()ed processes */ + mutex_lock(&watchdog.lock); + watchdog.expect_close = expect_close; + mutex_unlock(&watchdog.lock); + } + + /* someone wrote to us, we should restart timer */ + watchdog_keepalive(); + } + return count; +} + +/* + * watchdog_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 long watchdog_ioctl(struct file *file, unsigned int cmd, + unsigned long arg) +{ + int status; + int new_options; + int new_timeout; + union { + struct watchdog_info __user *ident; + int __user *i; + } uarg; + + uarg.i = (int __user *)arg; + + switch (cmd) { + case WDIOC_GETSUPPORT: + return copy_to_user(uarg.ident, &watchdog.ident, + sizeof(watchdog.ident)) ? -EFAULT : 0; + + case WDIOC_GETSTATUS: + status = watchdog_get_status(); + if (status < 0) + return status; + return put_user(status, uarg.i); + + case WDIOC_GETBOOTSTATUS: + return put_user(0, uarg.i); + + case WDIOC_SETOPTIONS: + if (get_user(new_options, uarg.i)) + return -EFAULT; + + if (new_options & WDIOS_DISABLECARD) + watchdog_stop(); + + if (new_options & WDIOS_ENABLECARD) + return watchdog_start(); + + + case WDIOC_KEEPALIVE: + watchdog_keepalive(); + return 0; + + case WDIOC_SETTIMEOUT: + if (get_user(new_timeout, uarg.i)) + return -EFAULT; + + if (watchdog_set_timeout(new_timeout)) + return -EINVAL; + + watchdog_keepalive(); + /* Fall */ + + case WDIOC_GETTIMEOUT: + return put_user(watchdog.timeout, uarg.i); + + default: + return -ENOTTY; + + } +} + +static int watchdog_notify_sys(struct notifier_block *this, unsigned long code, + void *unused) +{ + if (code == SYS_DOWN || code == SYS_HALT) + watchdog_stop(); + return NOTIFY_DONE; +} + +static const struct file_operations watchdog_fops = { + .owner = THIS_MODULE, + .llseek = no_llseek, + .open = watchdog_open, + .release = watchdog_release, + .write = watchdog_write, + .unlocked_ioctl = watchdog_ioctl, +}; + +static struct miscdevice watchdog_miscdev = { + .minor = WATCHDOG_MINOR, + .name = "watchdog", + .fops = &watchdog_fops, +}; + +static struct notifier_block watchdog_notifier = { + .notifier_call = watchdog_notify_sys, +}; + +static int __init watchdog_init(int sioaddr) +{ + int wdt_conf, err = 0; + + /* No need to lock watchdog.lock here because no entry points + * into the module have been registered yet. + */ + watchdog.sioaddr = sioaddr; + watchdog.ident.options = WDIOC_SETTIMEOUT + | WDIOF_MAGICCLOSE + | WDIOF_KEEPALIVEPING; + + snprintf(watchdog.ident.identity, + sizeof(watchdog.ident.identity), "%s watchdog", + f71808e_names[watchdog.type]); + + err = superio_enter(sioaddr); + if (err) + return err; + superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT); + + wdt_conf = superio_inb(sioaddr, F71808FG_REG_WDT_CONF); + watchdog.caused_reboot = wdt_conf & F71808FG_FLAG_WDTMOUT_STS; + + superio_exit(sioaddr); + + err = watchdog_set_timeout(timeout); + if (err) + return err; + err = watchdog_set_pulse_width(pulse_width); + if (err) + return err; + + err = register_reboot_notifier(&watchdog_notifier); + if (err) + return err; + + err = misc_register(&watchdog_miscdev); + if (err) { + printk(KERN_ERR DRVNAME + ": cannot register miscdev on minor=%d\n", + watchdog_miscdev.minor); + goto exit_reboot; + } + + if (start_withtimeout) { + if (start_withtimeout <= 0 + || start_withtimeout > max_timeout) { + printk(KERN_ERR DRVNAME + ": starting timeout out of range\n"); + err = -EINVAL; + goto exit_miscdev; + } + + err = watchdog_start(); + if (err) { + printk(KERN_ERR DRVNAME + ": cannot start watchdog timer\n"); + goto exit_miscdev; + } + + mutex_lock(&watchdog.lock); + err = superio_enter(sioaddr); + if (err) + goto exit_unlock; + superio_select(watchdog.sioaddr, SIO_F71808FG_LD_WDT); + + if (start_withtimeout > 0xff) { + /* select minutes for timer units */ + superio_set_bit(sioaddr, F71808FG_REG_WDT_CONF, + F71808FG_FLAG_WD_UNIT); + superio_outb(sioaddr, F71808FG_REG_WD_TIME, + DIV_ROUND_UP(start_withtimeout, 60)); + } else { + /* select seconds for timer units */ + superio_clear_bit(sioaddr, F71808FG_REG_WDT_CONF, + F71808FG_FLAG_WD_UNIT); + superio_outb(sioaddr, F71808FG_REG_WD_TIME, + start_withtimeout); + } + + superio_exit(sioaddr); + mutex_unlock(&watchdog.lock); + + if (nowayout) + __module_get(THIS_MODULE); + + printk(KERN_INFO DRVNAME + ": watchdog started with initial timeout of %u sec\n", + start_withtimeout); + } + + return 0; + +exit_unlock: + mutex_unlock(&watchdog.lock); +exit_miscdev: + misc_deregister(&watchdog_miscdev); +exit_reboot: + unregister_reboot_notifier(&watchdog_notifier); + + return err; +} + +static int __init f71808e_find(int sioaddr) +{ + u16 devid; + int err = superio_enter(sioaddr); + if (err) + return err; + + devid = superio_inw(sioaddr, SIO_REG_MANID); + if (devid != SIO_FINTEK_ID) { + pr_debug(DRVNAME ": Not a Fintek device\n"); + err = -ENODEV; + goto exit; + } + + devid = force_id ? force_id : superio_inw(sioaddr, SIO_REG_DEVID); + switch (devid) { + case SIO_F71808_ID: + watchdog.type = f71808fg; + break; + case SIO_F71882_ID: + watchdog.type = f71882fg; + break; + case SIO_F71862_ID: + case SIO_F71889_ID: + /* These have a watchdog, though it isn't implemented (yet). */ + err = -ENOSYS; + goto exit; + case SIO_F71858_ID: + /* Confirmed (by datasheet) not to have a watchdog. */ + err = -ENODEV; + goto exit; + default: + printk(KERN_INFO DRVNAME ": Unrecognized Fintek device: %04x\n", + (unsigned int)devid); + err = -ENODEV; + goto exit; + } + + printk(KERN_INFO DRVNAME ": Found %s watchdog chip, revision %d\n", + f71808e_names[watchdog.type], + (int)superio_inb(sioaddr, SIO_REG_DEVREV)); +exit: + superio_exit(sioaddr); + return err; +} + +static int __init f71808e_init(void) +{ + static const unsigned short addrs[] = { 0x2e, 0x4e }; + int err = -ENODEV; + int i; + + for (i = 0; i < ARRAY_SIZE(addrs); i++) { + err = f71808e_find(addrs[i]); + if (err == 0) + break; + } + if (i == ARRAY_SIZE(addrs)) + return err; + + return watchdog_init(addrs[i]); +} + +static void __exit f71808e_exit(void) +{ + if (watchdog_is_running()) { + printk(KERN_WARNING DRVNAME + ": Watchdog timer still running, stopping it\n"); + watchdog_stop(); + } + misc_deregister(&watchdog_miscdev); + unregister_reboot_notifier(&watchdog_notifier); +} + +MODULE_DESCRIPTION("F71808E Watchdog Driver"); +MODULE_AUTHOR("Giel van Schijndel <me@mortis.eu>"); +MODULE_LICENSE("GPL"); + +module_init(f71808e_init); +module_exit(f71808e_exit); |