diff options
Diffstat (limited to 'drivers/char/watchdog/wdrtas.c')
| -rw-r--r-- | drivers/char/watchdog/wdrtas.c | 695 |
1 files changed, 0 insertions, 695 deletions
diff --git a/drivers/char/watchdog/wdrtas.c b/drivers/char/watchdog/wdrtas.c deleted file mode 100644 index 1d64e27..0000000 --- a/drivers/char/watchdog/wdrtas.c +++ /dev/null @@ -1,695 +0,0 @@ -/* - * FIXME: add wdrtas_get_status and wdrtas_get_boot_status as soon as - * RTAS calls are available - */ - -/* - * RTAS watchdog driver - * - * (C) Copyright IBM Corp. 2005 - * device driver to exploit watchdog RTAS functions - * - * Authors : Utz Bacher <utz.bacher@de.ibm.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, 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., 675 Mass Ave, Cambridge, MA 02139, USA. - */ - -#include <linux/fs.h> -#include <linux/init.h> -#include <linux/kernel.h> -#include <linux/miscdevice.h> -#include <linux/module.h> -#include <linux/notifier.h> -#include <linux/reboot.h> -#include <linux/types.h> -#include <linux/watchdog.h> - -#include <asm/rtas.h> -#include <asm/uaccess.h> - -#define WDRTAS_MAGIC_CHAR 42 -#define WDRTAS_SUPPORTED_MASK (WDIOF_SETTIMEOUT | \ - WDIOF_MAGICCLOSE) - -MODULE_AUTHOR("Utz Bacher <utz.bacher@de.ibm.com>"); -MODULE_DESCRIPTION("RTAS watchdog driver"); -MODULE_LICENSE("GPL"); -MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); -MODULE_ALIAS_MISCDEV(TEMP_MINOR); - -#ifdef CONFIG_WATCHDOG_NOWAYOUT -static int wdrtas_nowayout = 1; -#else -static int wdrtas_nowayout = 0; -#endif - -static atomic_t wdrtas_miscdev_open = ATOMIC_INIT(0); -static char wdrtas_expect_close = 0; - -static int wdrtas_interval; - -#define WDRTAS_THERMAL_SENSOR 3 -static int wdrtas_token_get_sensor_state; -#define WDRTAS_SURVEILLANCE_IND 9000 -static int wdrtas_token_set_indicator; -#define WDRTAS_SP_SPI 28 -static int wdrtas_token_get_sp; -static int wdrtas_token_event_scan; - -#define WDRTAS_DEFAULT_INTERVAL 300 - -#define WDRTAS_LOGBUFFER_LEN 128 -static char wdrtas_logbuffer[WDRTAS_LOGBUFFER_LEN]; - - -/*** watchdog access functions */ - -/** - * wdrtas_set_interval - sets the watchdog interval - * @interval: new interval - * - * returns 0 on success, <0 on failures - * - * wdrtas_set_interval sets the watchdog keepalive interval by calling the - * RTAS function set-indicator (surveillance). The unit of interval is - * seconds. - */ -static int -wdrtas_set_interval(int interval) -{ - long result; - static int print_msg = 10; - - /* rtas uses minutes */ - interval = (interval + 59) / 60; - - result = rtas_call(wdrtas_token_set_indicator, 3, 1, NULL, - WDRTAS_SURVEILLANCE_IND, 0, interval); - if ( (result < 0) && (print_msg) ) { - printk(KERN_ERR "wdrtas: setting the watchdog to %i " - "timeout failed: %li\n", interval, result); - print_msg--; - } - - return result; -} - -/** - * wdrtas_get_interval - returns the current watchdog interval - * @fallback_value: value (in seconds) to use, if the RTAS call fails - * - * returns the interval - * - * wdrtas_get_interval returns the current watchdog keepalive interval - * as reported by the RTAS function ibm,get-system-parameter. The unit - * of the return value is seconds. - */ -static int -wdrtas_get_interval(int fallback_value) -{ - long result; - char value[4]; - - result = rtas_call(wdrtas_token_get_sp, 3, 1, NULL, - WDRTAS_SP_SPI, (void *)__pa(&value), 4); - if ( (value[0] != 0) || (value[1] != 2) || (value[3] != 0) || - (result < 0) ) { - printk(KERN_WARNING "wdrtas: could not get sp_spi watchdog " - "timeout (%li). Continuing\n", result); - return fallback_value; - } - - /* rtas uses minutes */ - return ((int)value[2]) * 60; -} - -/** - * wdrtas_timer_start - starts watchdog - * - * wdrtas_timer_start starts the watchdog by calling the RTAS function - * set-interval (surveillance) - */ -static void -wdrtas_timer_start(void) -{ - wdrtas_set_interval(wdrtas_interval); -} - -/** - * wdrtas_timer_stop - stops watchdog - * - * wdrtas_timer_stop stops the watchdog timer by calling the RTAS function - * set-interval (surveillance) - */ -static void -wdrtas_timer_stop(void) -{ - wdrtas_set_interval(0); -} - -/** - * wdrtas_log_scanned_event - logs an event we received during keepalive - * - * wdrtas_log_scanned_event prints a message to the log buffer dumping - * the results of the last event-scan call - */ -static void -wdrtas_log_scanned_event(void) -{ - int i; - - for (i = 0; i < WDRTAS_LOGBUFFER_LEN; i += 16) - printk(KERN_INFO "wdrtas: dumping event (line %i/%i), data = " - "%02x %02x %02x %02x %02x %02x %02x %02x " - "%02x %02x %02x %02x %02x %02x %02x %02x\n", - (i / 16) + 1, (WDRTAS_LOGBUFFER_LEN / 16), - wdrtas_logbuffer[i + 0], wdrtas_logbuffer[i + 1], - wdrtas_logbuffer[i + 2], wdrtas_logbuffer[i + 3], - wdrtas_logbuffer[i + 4], wdrtas_logbuffer[i + 5], - wdrtas_logbuffer[i + 6], wdrtas_logbuffer[i + 7], - wdrtas_logbuffer[i + 8], wdrtas_logbuffer[i + 9], - wdrtas_logbuffer[i + 10], wdrtas_logbuffer[i + 11], - wdrtas_logbuffer[i + 12], wdrtas_logbuffer[i + 13], - wdrtas_logbuffer[i + 14], wdrtas_logbuffer[i + 15]); -} - -/** - * wdrtas_timer_keepalive - resets watchdog timer to keep system alive - * - * wdrtas_timer_keepalive restarts the watchdog timer by calling the - * RTAS function event-scan and repeats these calls as long as there are - * events available. All events will be dumped. - */ -static void -wdrtas_timer_keepalive(void) -{ - long result; - - do { - result = rtas_call(wdrtas_token_event_scan, 4, 1, NULL, - RTAS_EVENT_SCAN_ALL_EVENTS, 0, - (void *)__pa(wdrtas_logbuffer), - WDRTAS_LOGBUFFER_LEN); - if (result < 0) - printk(KERN_ERR "wdrtas: event-scan failed: %li\n", - result); - if (result == 0) - wdrtas_log_scanned_event(); - } while (result == 0); -} - -/** - * wdrtas_get_temperature - returns current temperature - * - * returns temperature or <0 on failures - * - * wdrtas_get_temperature returns the current temperature in Fahrenheit. It - * uses the RTAS call get-sensor-state, token 3 to do so - */ -static int -wdrtas_get_temperature(void) -{ - long result; - int temperature = 0; - - result = rtas_call(wdrtas_token_get_sensor_state, 2, 2, - (void *)__pa(&temperature), - WDRTAS_THERMAL_SENSOR, 0); - - if (result < 0) - printk(KERN_WARNING "wdrtas: reading the thermal sensor " - "faild: %li\n", result); - else - temperature = ((temperature * 9) / 5) + 32; /* fahrenheit */ - - return temperature; -} - -/** - * wdrtas_get_status - returns the status of the watchdog - * - * returns a bitmask of defines WDIOF_... as defined in - * include/linux/watchdog.h - */ -static int -wdrtas_get_status(void) -{ - return 0; /* TODO */ -} - -/** - * wdrtas_get_boot_status - returns the reason for the last boot - * - * returns a bitmask of defines WDIOF_... as defined in - * include/linux/watchdog.h, indicating why the watchdog rebooted the system - */ -static int -wdrtas_get_boot_status(void) -{ - return 0; /* TODO */ -} - -/*** watchdog API and operations stuff */ - -/* wdrtas_write - called when watchdog device is written to - * @file: file structure - * @buf: user buffer with data - * @len: amount to data written - * @ppos: position in file - * - * returns the number of successfully processed characters, which is always - * the number of bytes passed to this function - * - * wdrtas_write processes all the data given to it and looks for the magic - * character 'V'. This character allows the watchdog device to be closed - * properly. - */ -static ssize_t -wdrtas_write(struct file *file, const char __user *buf, - size_t len, loff_t *ppos) -{ - int i; - char c; - - if (!len) - goto out; - - if (!wdrtas_nowayout) { - wdrtas_expect_close = 0; - /* look for 'V' */ - for (i = 0; i < len; i++) { - if (get_user(c, buf + i)) - return -EFAULT; - /* allow to close device */ - if (c == 'V') - wdrtas_expect_close = WDRTAS_MAGIC_CHAR; - } - } - - wdrtas_timer_keepalive(); - -out: - return len; -} - -/** - * wdrtas_ioctl - ioctl function for the watchdog device - * @inode: inode structure - * @file: file structure - * @cmd: command for ioctl - * @arg: argument pointer - * - * returns 0 on success, <0 on failure - * - * wdrtas_ioctl implements the watchdog API ioctls - */ -static int -wdrtas_ioctl(struct inode *inode, struct file *file, - unsigned int cmd, unsigned long arg) -{ - int __user *argp = (void __user *)arg; - int i; - static struct watchdog_info wdinfo = { - .options = WDRTAS_SUPPORTED_MASK, - .firmware_version = 0, - .identity = "wdrtas" - }; - - switch (cmd) { - case WDIOC_GETSUPPORT: - if (copy_to_user(argp, &wdinfo, sizeof(wdinfo))) - return -EFAULT; - return 0; - - case WDIOC_GETSTATUS: - i = wdrtas_get_status(); - return put_user(i, argp); - - case WDIOC_GETBOOTSTATUS: - i = wdrtas_get_boot_status(); - return put_user(i, argp); - - case WDIOC_GETTEMP: - if (wdrtas_token_get_sensor_state == RTAS_UNKNOWN_SERVICE) - return -EOPNOTSUPP; - - i = wdrtas_get_temperature(); - return put_user(i, argp); - - case WDIOC_SETOPTIONS: - if (get_user(i, argp)) - return -EFAULT; - if (i & WDIOS_DISABLECARD) - wdrtas_timer_stop(); - if (i & WDIOS_ENABLECARD) { - wdrtas_timer_keepalive(); - wdrtas_timer_start(); - } - if (i & WDIOS_TEMPPANIC) { - /* not implemented. Done by H8 */ - } - return 0; - - case WDIOC_KEEPALIVE: - wdrtas_timer_keepalive(); - return 0; - - case WDIOC_SETTIMEOUT: - if (get_user(i, argp)) - return -EFAULT; - - if (wdrtas_set_interval(i)) - return -EINVAL; - - wdrtas_timer_keepalive(); - - if (wdrtas_token_get_sp == RTAS_UNKNOWN_SERVICE) - wdrtas_interval = i; - else - wdrtas_interval = wdrtas_get_interval(i); - /* fallthrough */ - - case WDIOC_GETTIMEOUT: - return put_user(wdrtas_interval, argp); - - default: - return -ENOTTY; - } -} - -/** - * wdrtas_open - open function of watchdog device - * @inode: inode structure - * @file: file structure - * - * returns 0 on success, -EBUSY if the file has been opened already, <0 on - * other failures - * - * function called when watchdog device is opened - */ -static int -wdrtas_open(struct inode *inode, struct file *file) -{ - /* only open once */ - if (atomic_inc_return(&wdrtas_miscdev_open) > 1) { - atomic_dec(&wdrtas_miscdev_open); - return -EBUSY; - } - - wdrtas_timer_start(); - wdrtas_timer_keepalive(); - - return nonseekable_open(inode, file); -} - -/** - * wdrtas_close - close function of watchdog device - * @inode: inode structure - * @file: file structure - * - * returns 0 on success - * - * close function. Always succeeds - */ -static int -wdrtas_close(struct inode *inode, struct file *file) -{ - /* only stop watchdog, if this was announced using 'V' before */ - if (wdrtas_expect_close == WDRTAS_MAGIC_CHAR) - wdrtas_timer_stop(); - else { - printk(KERN_WARNING "wdrtas: got unexpected close. Watchdog " - "not stopped.\n"); - wdrtas_timer_keepalive(); - } - - wdrtas_expect_close = 0; - atomic_dec(&wdrtas_miscdev_open); - return 0; -} - -/** - * wdrtas_temp_read - gives back the temperature in fahrenheit - * @file: file structure - * @buf: user buffer - * @count: number of bytes to be read - * @ppos: position in file - * - * returns always 1 or -EFAULT in case of user space copy failures, <0 on - * other failures - * - * wdrtas_temp_read gives the temperature to the users by copying this - * value as one byte into the user space buffer. The unit is Fahrenheit... - */ -static ssize_t -wdrtas_temp_read(struct file *file, char __user *buf, - size_t count, loff_t *ppos) -{ - int temperature = 0; - - temperature = wdrtas_get_temperature(); - if (temperature < 0) - return temperature; - - if (copy_to_user(buf, &temperature, 1)) - return -EFAULT; - - return 1; -} - -/** - * wdrtas_temp_open - open function of temperature device - * @inode: inode structure - * @file: file structure - * - * returns 0 on success, <0 on failure - * - * function called when temperature device is opened - */ -static int -wdrtas_temp_open(struct inode *inode, struct file *file) -{ - return nonseekable_open(inode, file); -} - -/** - * wdrtas_temp_close - close function of temperature device - * @inode: inode structure - * @file: file structure - * - * returns 0 on success - * - * close function. Always succeeds - */ -static int -wdrtas_temp_close(struct inode *inode, struct file *file) -{ - return 0; -} - -/** - * wdrtas_reboot - reboot notifier function - * @nb: notifier block structure - * @code: reboot code - * @ptr: unused - * - * returns NOTIFY_DONE - * - * wdrtas_reboot stops the watchdog in case of a reboot - */ -static int -wdrtas_reboot(struct notifier_block *this, unsigned long code, void *ptr) -{ - if ( (code==SYS_DOWN) || (code==SYS_HALT) ) - wdrtas_timer_stop(); - - return NOTIFY_DONE; -} - -/*** initialization stuff */ - -static const struct file_operations wdrtas_fops = { - .owner = THIS_MODULE, - .llseek = no_llseek, - .write = wdrtas_write, - .ioctl = wdrtas_ioctl, - .open = wdrtas_open, - .release = wdrtas_close, -}; - -static struct miscdevice wdrtas_miscdev = { - .minor = WATCHDOG_MINOR, - .name = "watchdog", - .fops = &wdrtas_fops, -}; - -static const struct file_operations wdrtas_temp_fops = { - .owner = THIS_MODULE, - .llseek = no_llseek, - .read = wdrtas_temp_read, - .open = wdrtas_temp_open, - .release = wdrtas_temp_close, -}; - -static struct miscdevice wdrtas_tempdev = { - .minor = TEMP_MINOR, - .name = "temperature", - .fops = &wdrtas_temp_fops, -}; - -static struct notifier_block wdrtas_notifier = { - .notifier_call = wdrtas_reboot, -}; - -/** - * wdrtas_get_tokens - reads in RTAS tokens - * - * returns 0 on succes, <0 on failure - * - * wdrtas_get_tokens reads in the tokens for the RTAS calls used in - * this watchdog driver. It tolerates, if "get-sensor-state" and - * "ibm,get-system-parameter" are not available. - */ -static int -wdrtas_get_tokens(void) -{ - wdrtas_token_get_sensor_state = rtas_token("get-sensor-state"); - if (wdrtas_token_get_sensor_state == RTAS_UNKNOWN_SERVICE) { - printk(KERN_WARNING "wdrtas: couldn't get token for " - "get-sensor-state. Trying to continue without " - "temperature support.\n"); - } - - wdrtas_token_get_sp = rtas_token("ibm,get-system-parameter"); - if (wdrtas_token_get_sp == RTAS_UNKNOWN_SERVICE) { - printk(KERN_WARNING "wdrtas: couldn't get token for " - "ibm,get-system-parameter. Trying to continue with " - "a default timeout value of %i seconds.\n", - WDRTAS_DEFAULT_INTERVAL); - } - - wdrtas_token_set_indicator = rtas_token("set-indicator"); - if (wdrtas_token_set_indicator == RTAS_UNKNOWN_SERVICE) { - printk(KERN_ERR "wdrtas: couldn't get token for " - "set-indicator. Terminating watchdog code.\n"); - return -EIO; - } - - wdrtas_token_event_scan = rtas_token("event-scan"); - if (wdrtas_token_event_scan == RTAS_UNKNOWN_SERVICE) { - printk(KERN_ERR "wdrtas: couldn't get token for event-scan. " - "Terminating watchdog code.\n"); - return -EIO; - } - - return 0; -} - -/** - * wdrtas_unregister_devs - unregisters the misc dev handlers - * - * wdrtas_register_devs unregisters the watchdog and temperature watchdog - * misc devs - */ -static void -wdrtas_unregister_devs(void) -{ - misc_deregister(&wdrtas_miscdev); - if (wdrtas_token_get_sensor_state != RTAS_UNKNOWN_SERVICE) - misc_deregister(&wdrtas_tempdev); -} - -/** - * wdrtas_register_devs - registers the misc dev handlers - * - * returns 0 on succes, <0 on failure - * - * wdrtas_register_devs registers the watchdog and temperature watchdog - * misc devs - */ -static int -wdrtas_register_devs(void) -{ - int result; - - result = misc_register(&wdrtas_miscdev); - if (result) { - printk(KERN_ERR "wdrtas: couldn't register watchdog misc " - "device. Terminating watchdog code.\n"); - return result; - } - - if (wdrtas_token_get_sensor_state != RTAS_UNKNOWN_SERVICE) { - result = misc_register(&wdrtas_tempdev); - if (result) { - printk(KERN_WARNING "wdrtas: couldn't register " - "watchdog temperature misc device. Continuing " - "without temperature support.\n"); - wdrtas_token_get_sensor_state = RTAS_UNKNOWN_SERVICE; - } - } - - return 0; -} - -/** - * wdrtas_init - init function of the watchdog driver - * - * returns 0 on succes, <0 on failure - * - * registers the file handlers and the reboot notifier - */ -static int __init -wdrtas_init(void) -{ - if (wdrtas_get_tokens()) - return -ENODEV; - - if (wdrtas_register_devs()) - return -ENODEV; - - if (register_reboot_notifier(&wdrtas_notifier)) { - printk(KERN_ERR "wdrtas: could not register reboot notifier. " - "Terminating watchdog code.\n"); - wdrtas_unregister_devs(); - return -ENODEV; - } - - if (wdrtas_token_get_sp == RTAS_UNKNOWN_SERVICE) - wdrtas_interval = WDRTAS_DEFAULT_INTERVAL; - else - wdrtas_interval = wdrtas_get_interval(WDRTAS_DEFAULT_INTERVAL); - - return 0; -} - -/** - * wdrtas_exit - exit function of the watchdog driver - * - * unregisters the file handlers and the reboot notifier - */ -static void __exit -wdrtas_exit(void) -{ - if (!wdrtas_nowayout) - wdrtas_timer_stop(); - - wdrtas_unregister_devs(); - - unregister_reboot_notifier(&wdrtas_notifier); -} - -module_init(wdrtas_init); -module_exit(wdrtas_exit); |
