diff options
Diffstat (limited to 'drivers/watchdog/ep93xx_wdt.c')
-rw-r--r-- | drivers/watchdog/ep93xx_wdt.c | 220 |
1 files changed, 62 insertions, 158 deletions
diff --git a/drivers/watchdog/ep93xx_wdt.c b/drivers/watchdog/ep93xx_wdt.c index 09cd888..7705003 100644 --- a/drivers/watchdog/ep93xx_wdt.c +++ b/drivers/watchdog/ep93xx_wdt.c @@ -8,6 +8,9 @@ * Authors: Ray Lehtiniemi <rayl@mail.com>, * Alessandro Zummo <a.zummo@towertech.it> * + * Copyright (c) 2012 H Hartley Sweeten <hsweeten@visionengravers.com> + * Convert to a platform device and use the watchdog framework API + * * This file is licensed under the terms of the GNU General Public * License version 2. This program is licensed "as is" without any * warranty of any kind, whether express or implied. @@ -25,187 +28,90 @@ #include <linux/platform_device.h> #include <linux/module.h> -#include <linux/fs.h> #include <linux/miscdevice.h> #include <linux/watchdog.h> #include <linux/timer.h> -#include <linux/uaccess.h> #include <linux/io.h> -#define WDT_VERSION "0.3" -#define PFX "ep93xx_wdt: " +#define WDT_VERSION "0.4" /* default timeout (secs) */ #define WDT_TIMEOUT 30 -static int nowayout = WATCHDOG_NOWAYOUT; -static int timeout = WDT_TIMEOUT; +static bool nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, 0); +MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started"); + +static unsigned int timeout = WDT_TIMEOUT; +module_param(timeout, uint, 0); +MODULE_PARM_DESC(timeout, + "Watchdog timeout in seconds. (1<=timeout<=3600, default=" + __MODULE_STRING(WDT_TIMEOUT) ")"); static void __iomem *mmio_base; static struct timer_list timer; static unsigned long next_heartbeat; -static unsigned long wdt_status; -static unsigned long boot_status; - -#define WDT_IN_USE 0 -#define WDT_OK_TO_CLOSE 1 #define EP93XX_WATCHDOG 0x00 #define EP93XX_WDSTATUS 0x04 -/* reset the wdt every ~200ms */ +/* reset the wdt every ~200ms - the heartbeat of the device is 0.250 seconds*/ #define WDT_INTERVAL (HZ/5) -static void wdt_enable(void) +static void ep93xx_wdt_timer_ping(unsigned long data) { - writel(0xaaaa, mmio_base + EP93XX_WATCHDOG); -} - -static void wdt_disable(void) -{ - writel(0xaa55, mmio_base + EP93XX_WATCHDOG); -} + if (time_before(jiffies, next_heartbeat)) + writel(0x5555, mmio_base + EP93XX_WATCHDOG); -static inline void wdt_ping(void) -{ - writel(0x5555, mmio_base + EP93XX_WATCHDOG); + /* Re-set the timer interval */ + mod_timer(&timer, jiffies + WDT_INTERVAL); } -static void wdt_startup(void) +static int ep93xx_wdt_start(struct watchdog_device *wdd) { next_heartbeat = jiffies + (timeout * HZ); - wdt_enable(); + writel(0xaaaa, mmio_base + EP93XX_WATCHDOG); mod_timer(&timer, jiffies + WDT_INTERVAL); + + return 0; } -static void wdt_shutdown(void) +static int ep93xx_wdt_stop(struct watchdog_device *wdd) { del_timer_sync(&timer); - wdt_disable(); + writel(0xaa55, mmio_base + EP93XX_WATCHDOG); + + return 0; } -static void wdt_keepalive(void) +static int ep93xx_wdt_keepalive(struct watchdog_device *wdd) { /* user land ping */ next_heartbeat = jiffies + (timeout * HZ); -} - -static int ep93xx_wdt_open(struct inode *inode, struct file *file) -{ - if (test_and_set_bit(WDT_IN_USE, &wdt_status)) - return -EBUSY; - - clear_bit(WDT_OK_TO_CLOSE, &wdt_status); - - wdt_startup(); - - return nonseekable_open(inode, file); -} - -static ssize_t -ep93xx_wdt_write(struct file *file, const char __user *data, size_t len, - loff_t *ppos) -{ - if (len) { - if (!nowayout) { - size_t i; - - clear_bit(WDT_OK_TO_CLOSE, &wdt_status); - - for (i = 0; i != len; i++) { - char c; - - if (get_user(c, data + i)) - return -EFAULT; - - if (c == 'V') - set_bit(WDT_OK_TO_CLOSE, &wdt_status); - else - clear_bit(WDT_OK_TO_CLOSE, &wdt_status); - } - } - wdt_keepalive(); - } - return len; + return 0; } -static const struct watchdog_info ident = { - .options = WDIOF_CARDRESET | WDIOF_MAGICCLOSE, - .identity = "EP93xx Watchdog", +static const struct watchdog_info ep93xx_wdt_ident = { + .options = WDIOF_CARDRESET | + WDIOF_MAGICCLOSE | + WDIOF_KEEPALIVEPING, + .identity = "EP93xx Watchdog", }; -static long ep93xx_wdt_ioctl(struct file *file, - unsigned int cmd, unsigned long arg) -{ - int ret = -ENOTTY; - - switch (cmd) { - case WDIOC_GETSUPPORT: - ret = copy_to_user((struct watchdog_info __user *)arg, &ident, - sizeof(ident)) ? -EFAULT : 0; - break; - - case WDIOC_GETSTATUS: - ret = put_user(0, (int __user *)arg); - break; - - case WDIOC_GETBOOTSTATUS: - ret = put_user(boot_status, (int __user *)arg); - break; - - case WDIOC_KEEPALIVE: - wdt_keepalive(); - ret = 0; - break; - - case WDIOC_GETTIMEOUT: - /* actually, it is 0.250 seconds.... */ - ret = put_user(1, (int __user *)arg); - break; - } - return ret; -} - -static int ep93xx_wdt_release(struct inode *inode, struct file *file) -{ - if (test_bit(WDT_OK_TO_CLOSE, &wdt_status)) - wdt_shutdown(); - else - printk(KERN_CRIT PFX - "Device closed unexpectedly - timer will not stop\n"); - - clear_bit(WDT_IN_USE, &wdt_status); - clear_bit(WDT_OK_TO_CLOSE, &wdt_status); - - return 0; -} - -static const struct file_operations ep93xx_wdt_fops = { +static struct watchdog_ops ep93xx_wdt_ops = { .owner = THIS_MODULE, - .write = ep93xx_wdt_write, - .unlocked_ioctl = ep93xx_wdt_ioctl, - .open = ep93xx_wdt_open, - .release = ep93xx_wdt_release, - .llseek = no_llseek, + .start = ep93xx_wdt_start, + .stop = ep93xx_wdt_stop, + .ping = ep93xx_wdt_keepalive, }; -static struct miscdevice ep93xx_wdt_miscdev = { - .minor = WATCHDOG_MINOR, - .name = "watchdog", - .fops = &ep93xx_wdt_fops, +static struct watchdog_device ep93xx_wdt_wdd = { + .info = &ep93xx_wdt_ident, + .ops = &ep93xx_wdt_ops, }; -static void ep93xx_timer_ping(unsigned long data) -{ - if (time_before(jiffies, next_heartbeat)) - wdt_ping(); - - /* Re-set the timer interval */ - mod_timer(&timer, jiffies + WDT_INTERVAL); -} - static int __devinit ep93xx_wdt_probe(struct platform_device *pdev) { struct resource *res; @@ -224,30 +130,35 @@ static int __devinit ep93xx_wdt_probe(struct platform_device *pdev) if (!mmio_base) return -ENXIO; - err = misc_register(&ep93xx_wdt_miscdev); - - val = readl(mmio_base + EP93XX_WATCHDOG); - boot_status = val & 0x01 ? 1 : 0; - - printk(KERN_INFO PFX "EP93XX watchdog, driver version " - WDT_VERSION "%s\n", - (val & 0x08) ? " (nCS1 disable detected)" : ""); - if (timeout < 1 || timeout > 3600) { timeout = WDT_TIMEOUT; - printk(KERN_INFO PFX + dev_warn(&pdev->dev, "timeout value must be 1<=x<=3600, using %d\n", timeout); } - setup_timer(&timer, ep93xx_timer_ping, 1); - return err; + val = readl(mmio_base + EP93XX_WATCHDOG); + ep93xx_wdt_wdd.bootstatus = (val & 0x01) ? WDIOF_CARDRESET : 0; + ep93xx_wdt_wdd.timeout = timeout; + + watchdog_set_nowayout(&ep93xx_wdt_wdd, nowayout); + + setup_timer(&timer, ep93xx_wdt_timer_ping, 1); + + err = watchdog_register_device(&ep93xx_wdt_wdd); + if (err) + return err; + + dev_info(&pdev->dev, + "EP93XX watchdog, driver version " WDT_VERSION "%s\n", + (val & 0x08) ? " (nCS1 disable detected)" : ""); + + return 0; } static int __devexit ep93xx_wdt_remove(struct platform_device *pdev) { - wdt_shutdown(); - misc_deregister(&ep93xx_wdt_miscdev); + watchdog_unregister_device(&ep93xx_wdt_wdd); return 0; } @@ -262,16 +173,9 @@ static struct platform_driver ep93xx_wdt_driver = { module_platform_driver(ep93xx_wdt_driver); -module_param(nowayout, int, 0); -MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started"); - -module_param(timeout, int, 0); -MODULE_PARM_DESC(timeout, - "Watchdog timeout in seconds. (1<=timeout<=3600, default=" - __MODULE_STRING(WDT_TIMEOUT) ")"); - MODULE_AUTHOR("Ray Lehtiniemi <rayl@mail.com>," - "Alessandro Zummo <a.zummo@towertech.it>"); + "Alessandro Zummo <a.zummo@towertech.it>," + "H Hartley Sweeten <hsweeten@visionengravers.com>"); MODULE_DESCRIPTION("EP93xx Watchdog"); MODULE_LICENSE("GPL"); MODULE_VERSION(WDT_VERSION); |