From 4a516539faba13deca2399cff8faaa84d251a4ea Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Mon, 12 Mar 2012 09:52:16 +0530 Subject: [PATCH] watchdog: sp805_wdt: convert to watchdog core This patch converts existing sp805 watchdog driver to use already in place common infrastructure present in watchdog core. With this lot of code goes away. Signed-off-by: Viresh Kumar Signed-off-by: Wim Van Sebroeck --- drivers/watchdog/Kconfig | 1 + drivers/watchdog/sp805_wdt.c | 241 ++++++++++++----------------------- 2 files changed, 83 insertions(+), 159 deletions(-) diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig index 004e26152460..fe819b76de56 100644 --- a/drivers/watchdog/Kconfig +++ b/drivers/watchdog/Kconfig @@ -99,6 +99,7 @@ config WM8350_WATCHDOG config ARM_SP805_WATCHDOG tristate "ARM SP805 Watchdog" depends on ARM_AMBA + select WATCHDOG_CORE help ARM Primecell SP805 Watchdog timer. This will reboot your system when the timeout is reached. diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c index bbb170e50055..18d4bcfd1bfc 100644 --- a/drivers/watchdog/sp805_wdt.c +++ b/drivers/watchdog/sp805_wdt.c @@ -16,20 +16,17 @@ #include #include #include -#include #include #include #include #include #include -#include #include #include #include #include #include #include -#include #include /* default timeout in seconds */ @@ -56,6 +53,7 @@ /** * struct sp805_wdt: sp805 wdt device structure + * @wdd: instance of struct watchdog_device * @lock: spin lock protecting dev structure and io access * @base: base address of wdt * @clk: clock structure of wdt @@ -65,24 +63,24 @@ * @timeout: current programmed timeout */ struct sp805_wdt { + struct watchdog_device wdd; spinlock_t lock; void __iomem *base; struct clk *clk; struct amba_device *adev; - unsigned long status; - #define WDT_BUSY 0 - #define WDT_CAN_BE_CLOSED 1 unsigned int load_val; unsigned int timeout; }; -/* local variables */ -static struct sp805_wdt *wdt; static bool nowayout = WATCHDOG_NOWAYOUT; +module_param(nowayout, bool, 0); +MODULE_PARM_DESC(nowayout, + "Set to 1 to keep watchdog running after device release"); /* This routine finds load value that will reset system in required timout */ -static void wdt_setload(unsigned int timeout) +static int wdt_setload(struct watchdog_device *wdd, unsigned int timeout) { + struct sp805_wdt *wdt = watchdog_get_drvdata(wdd); u64 load, rate; rate = clk_get_rate(wdt->clk); @@ -103,11 +101,14 @@ static void wdt_setload(unsigned int timeout) /* roundup timeout to closest positive integer value */ wdt->timeout = div_u64((load + 1) * 2 + (rate / 2), rate); spin_unlock(&wdt->lock); + + return 0; } /* returns number of seconds left for reset to occur */ -static u32 wdt_timeleft(void) +static unsigned int wdt_timeleft(struct watchdog_device *wdd) { + struct sp805_wdt *wdt = watchdog_get_drvdata(wdd); u64 load, rate; rate = clk_get_rate(wdt->clk); @@ -123,166 +124,88 @@ static u32 wdt_timeleft(void) return div_u64(load, rate); } -/* enables watchdog timers reset */ -static void wdt_enable(void) +static int wdt_config(struct watchdog_device *wdd, bool ping) { + struct sp805_wdt *wdt = watchdog_get_drvdata(wdd); + int ret; + + if (!ping) { + ret = clk_enable(wdt->clk); + if (ret) { + dev_err(&wdt->adev->dev, "clock enable fail"); + return ret; + } + } + spin_lock(&wdt->lock); writel_relaxed(UNLOCK, wdt->base + WDTLOCK); writel_relaxed(wdt->load_val, wdt->base + WDTLOAD); - writel_relaxed(INT_MASK, wdt->base + WDTINTCLR); - writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base + WDTCONTROL); - writel_relaxed(LOCK, wdt->base + WDTLOCK); - - /* Flush posted writes. */ - readl_relaxed(wdt->base + WDTLOCK); - spin_unlock(&wdt->lock); -} -/* disables watchdog timers reset */ -static void wdt_disable(void) -{ - spin_lock(&wdt->lock); + if (!ping) { + writel_relaxed(INT_MASK, wdt->base + WDTINTCLR); + writel_relaxed(INT_ENABLE | RESET_ENABLE, wdt->base + + WDTCONTROL); + } - writel_relaxed(UNLOCK, wdt->base + WDTLOCK); - writel_relaxed(0, wdt->base + WDTCONTROL); writel_relaxed(LOCK, wdt->base + WDTLOCK); /* Flush posted writes. */ readl_relaxed(wdt->base + WDTLOCK); spin_unlock(&wdt->lock); + + return 0; } -static ssize_t sp805_wdt_write(struct file *file, const char *data, - size_t len, loff_t *ppos) +static int wdt_ping(struct watchdog_device *wdd) { - if (len) { - if (!nowayout) { - size_t i; - - clear_bit(WDT_CAN_BE_CLOSED, &wdt->status); - - for (i = 0; i != len; i++) { - char c; - - if (get_user(c, data + i)) - return -EFAULT; - /* Check for Magic Close character */ - if (c == 'V') { - set_bit(WDT_CAN_BE_CLOSED, - &wdt->status); - break; - } - } - } - wdt_enable(); - } - return len; + return wdt_config(wdd, true); } -static const struct watchdog_info ident = { - .options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, - .identity = MODULE_NAME, -}; - -static long sp805_wdt_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) +/* enables watchdog timers reset */ +static int wdt_enable(struct watchdog_device *wdd) { - int ret = -ENOTTY; - unsigned int timeout; - - switch (cmd) { - case WDIOC_GETSUPPORT: - ret = copy_to_user((struct watchdog_info *)arg, &ident, - sizeof(ident)) ? -EFAULT : 0; - break; - - case WDIOC_GETSTATUS: - ret = put_user(0, (int *)arg); - break; - - case WDIOC_KEEPALIVE: - wdt_enable(); - ret = 0; - break; - - case WDIOC_SETTIMEOUT: - ret = get_user(timeout, (unsigned int *)arg); - if (ret) - break; - - wdt_setload(timeout); - - wdt_enable(); - /* Fall through */ - - case WDIOC_GETTIMEOUT: - ret = put_user(wdt->timeout, (unsigned int *)arg); - break; - case WDIOC_GETTIMELEFT: - ret = put_user(wdt_timeleft(), (unsigned int *)arg); - break; - } - return ret; + return wdt_config(wdd, false); } -static int sp805_wdt_open(struct inode *inode, struct file *file) +/* disables watchdog timers reset */ +static int wdt_disable(struct watchdog_device *wdd) { - int ret = 0; + struct sp805_wdt *wdt = watchdog_get_drvdata(wdd); - if (test_and_set_bit(WDT_BUSY, &wdt->status)) - return -EBUSY; - - ret = clk_enable(wdt->clk); - if (ret) { - dev_err(&wdt->adev->dev, "clock enable fail"); - goto err; - } - - wdt_enable(); - - /* can not be closed, once enabled */ - clear_bit(WDT_CAN_BE_CLOSED, &wdt->status); - return nonseekable_open(inode, file); + spin_lock(&wdt->lock); -err: - clear_bit(WDT_BUSY, &wdt->status); - return ret; -} + writel_relaxed(UNLOCK, wdt->base + WDTLOCK); + writel_relaxed(0, wdt->base + WDTCONTROL); + writel_relaxed(LOCK, wdt->base + WDTLOCK); -static int sp805_wdt_release(struct inode *inode, struct file *file) -{ - if (!test_bit(WDT_CAN_BE_CLOSED, &wdt->status)) { - clear_bit(WDT_BUSY, &wdt->status); - dev_warn(&wdt->adev->dev, "Device closed unexpectedly\n"); - return 0; - } + /* Flush posted writes. */ + readl_relaxed(wdt->base + WDTLOCK); + spin_unlock(&wdt->lock); - wdt_disable(); clk_disable(wdt->clk); - clear_bit(WDT_BUSY, &wdt->status); return 0; } -static const struct file_operations sp805_wdt_fops = { - .owner = THIS_MODULE, - .llseek = no_llseek, - .write = sp805_wdt_write, - .unlocked_ioctl = sp805_wdt_ioctl, - .open = sp805_wdt_open, - .release = sp805_wdt_release, +static const struct watchdog_info wdt_info = { + .options = WDIOF_MAGICCLOSE | WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, + .identity = MODULE_NAME, }; -static struct miscdevice sp805_wdt_miscdev = { - .minor = WATCHDOG_MINOR, - .name = "watchdog", - .fops = &sp805_wdt_fops, +static const struct watchdog_ops wdt_ops = { + .owner = THIS_MODULE, + .start = wdt_enable, + .stop = wdt_disable, + .ping = wdt_ping, + .set_timeout = wdt_setload, + .get_timeleft = wdt_timeleft, }; static int __devinit sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id) { + struct sp805_wdt *wdt; int ret = 0; if (!devm_request_mem_region(&adev->dev, adev->res.start, @@ -315,19 +238,26 @@ sp805_wdt_probe(struct amba_device *adev, const struct amba_id *id) } wdt->adev = adev; + wdt->wdd.info = &wdt_info; + wdt->wdd.ops = &wdt_ops; + spin_lock_init(&wdt->lock); - wdt_setload(DEFAULT_TIMEOUT); + watchdog_set_nowayout(&wdt->wdd, nowayout); + watchdog_set_drvdata(&wdt->wdd, wdt); + wdt_setload(&wdt->wdd, DEFAULT_TIMEOUT); - ret = misc_register(&sp805_wdt_miscdev); - if (ret < 0) { - dev_warn(&adev->dev, "cannot register misc device\n"); - goto err_misc_register; + ret = watchdog_register_device(&wdt->wdd); + if (ret) { + dev_err(&adev->dev, "watchdog_register_device() failed: %d\n", + ret); + goto err_register; } + amba_set_drvdata(adev, wdt); dev_info(&adev->dev, "registration successful\n"); return 0; -err_misc_register: +err_register: clk_put(wdt->clk); err: dev_err(&adev->dev, "Probe Failed!!!\n"); @@ -336,7 +266,11 @@ err: static int __devexit sp805_wdt_remove(struct amba_device *adev) { - misc_deregister(&sp805_wdt_miscdev); + struct sp805_wdt *wdt = amba_get_drvdata(adev); + + watchdog_unregister_device(&wdt->wdd); + amba_set_drvdata(adev, NULL); + watchdog_set_drvdata(&wdt->wdd, NULL); clk_put(wdt->clk); return 0; @@ -345,28 +279,22 @@ static int __devexit sp805_wdt_remove(struct amba_device *adev) #ifdef CONFIG_PM static int sp805_wdt_suspend(struct device *dev) { - if (test_bit(WDT_BUSY, &wdt->status)) { - wdt_disable(); - clk_disable(wdt->clk); - } + struct sp805_wdt *wdt = dev_get_drvdata(dev); + + if (watchdog_active(&wdt->wdd)) + return wdt_disable(&wdt->wdd); return 0; } static int sp805_wdt_resume(struct device *dev) { - int ret = 0; + struct sp805_wdt *wdt = dev_get_drvdata(dev); - if (test_bit(WDT_BUSY, &wdt->status)) { - ret = clk_enable(wdt->clk); - if (ret) { - dev_err(dev, "clock enable fail"); - return ret; - } - wdt_enable(); - } + if (watchdog_active(&wdt->wdd)) + return wdt_enable(&wdt->wdd); - return ret; + return 0; } #endif /* CONFIG_PM */ @@ -395,11 +323,6 @@ static struct amba_driver sp805_wdt_driver = { module_amba_driver(sp805_wdt_driver); -module_param(nowayout, bool, 0); -MODULE_PARM_DESC(nowayout, - "Set to 1 to keep watchdog running after device release"); - MODULE_AUTHOR("Viresh Kumar "); MODULE_DESCRIPTION("ARM SP805 Watchdog Driver"); MODULE_LICENSE("GPL"); -MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); -- 2.34.1