diff options
Diffstat (limited to 'drivers/watchdog/omap_wdt.c')
-rw-r--r-- | drivers/watchdog/omap_wdt.c | 312 |
1 files changed, 122 insertions, 190 deletions
diff --git a/drivers/watchdog/omap_wdt.c b/drivers/watchdog/omap_wdt.c index 3e3ebbc83faf..b0e541d022e6 100644 --- a/drivers/watchdog/omap_wdt.c +++ b/drivers/watchdog/omap_wdt.c @@ -31,42 +31,34 @@ #include <linux/module.h> #include <linux/types.h> #include <linux/kernel.h> -#include <linux/fs.h> #include <linux/mm.h> -#include <linux/miscdevice.h> #include <linux/watchdog.h> #include <linux/reboot.h> #include <linux/init.h> #include <linux/err.h> #include <linux/platform_device.h> #include <linux/moduleparam.h> -#include <linux/bitops.h> #include <linux/io.h> -#include <linux/uaccess.h> #include <linux/slab.h> #include <linux/pm_runtime.h> #include <linux/platform_data/omap-wd-timer.h> #include "omap_wdt.h" -static struct platform_device *omap_wdt_dev; - static unsigned timer_margin; module_param(timer_margin, uint, 0); MODULE_PARM_DESC(timer_margin, "initial watchdog timeout (in seconds)"); -static unsigned int wdt_trgr_pattern = 0x1234; -static DEFINE_SPINLOCK(wdt_lock); - struct omap_wdt_dev { void __iomem *base; /* physical */ struct device *dev; - int omap_wdt_users; + bool omap_wdt_users; struct resource *mem; - struct miscdevice omap_wdt_miscdev; + int wdt_trgr_pattern; + struct mutex lock; /* to avoid races with PM */ }; -static void omap_wdt_ping(struct omap_wdt_dev *wdev) +static void omap_wdt_reload(struct omap_wdt_dev *wdev) { void __iomem *base = wdev->base; @@ -74,8 +66,8 @@ static void omap_wdt_ping(struct omap_wdt_dev *wdev) while ((__raw_readl(base + OMAP_WATCHDOG_WPS)) & 0x08) cpu_relax(); - wdt_trgr_pattern = ~wdt_trgr_pattern; - __raw_writel(wdt_trgr_pattern, (base + OMAP_WATCHDOG_TGR)); + wdev->wdt_trgr_pattern = ~wdev->wdt_trgr_pattern; + __raw_writel(wdev->wdt_trgr_pattern, (base + OMAP_WATCHDOG_TGR)); /* wait for posted write to complete */ while ((__raw_readl(base + OMAP_WATCHDOG_WPS)) & 0x08) @@ -111,18 +103,10 @@ static void omap_wdt_disable(struct omap_wdt_dev *wdev) cpu_relax(); } -static void omap_wdt_adjust_timeout(unsigned new_timeout) -{ - if (new_timeout < TIMER_MARGIN_MIN) - new_timeout = TIMER_MARGIN_DEFAULT; - if (new_timeout > TIMER_MARGIN_MAX) - new_timeout = TIMER_MARGIN_MAX; - timer_margin = new_timeout; -} - -static void omap_wdt_set_timeout(struct omap_wdt_dev *wdev) +static void omap_wdt_set_timer(struct omap_wdt_dev *wdev, + unsigned int timeout) { - u32 pre_margin = GET_WLDR_VAL(timer_margin); + u32 pre_margin = GET_WLDR_VAL(timeout); void __iomem *base = wdev->base; /* just count up at 32 KHz */ @@ -134,16 +118,14 @@ static void omap_wdt_set_timeout(struct omap_wdt_dev *wdev) cpu_relax(); } -/* - * Allow only one task to hold it open - */ -static int omap_wdt_open(struct inode *inode, struct file *file) +static int omap_wdt_start(struct watchdog_device *wdog) { - struct omap_wdt_dev *wdev = platform_get_drvdata(omap_wdt_dev); + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); void __iomem *base = wdev->base; - if (test_and_set_bit(1, (unsigned long *)&(wdev->omap_wdt_users))) - return -EBUSY; + mutex_lock(&wdev->lock); + + wdev->omap_wdt_users = true; pm_runtime_get_sync(wdev->dev); @@ -155,223 +137,168 @@ static int omap_wdt_open(struct inode *inode, struct file *file) while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x01) cpu_relax(); - file->private_data = (void *) wdev; - - omap_wdt_set_timeout(wdev); - omap_wdt_ping(wdev); /* trigger loading of new timeout value */ + omap_wdt_set_timer(wdev, wdog->timeout); + omap_wdt_reload(wdev); /* trigger loading of new timeout value */ omap_wdt_enable(wdev); - return nonseekable_open(inode, file); + mutex_unlock(&wdev->lock); + + return 0; } -static int omap_wdt_release(struct inode *inode, struct file *file) +static int omap_wdt_stop(struct watchdog_device *wdog) { - struct omap_wdt_dev *wdev = file->private_data; + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); - /* - * Shut off the timer unless NOWAYOUT is defined. - */ -#ifndef CONFIG_WATCHDOG_NOWAYOUT + mutex_lock(&wdev->lock); omap_wdt_disable(wdev); - pm_runtime_put_sync(wdev->dev); -#else - pr_crit("Unexpected close, not stopping!\n"); -#endif - wdev->omap_wdt_users = 0; - + wdev->omap_wdt_users = false; + mutex_unlock(&wdev->lock); return 0; } -static ssize_t omap_wdt_write(struct file *file, const char __user *data, - size_t len, loff_t *ppos) +static int omap_wdt_ping(struct watchdog_device *wdog) { - struct omap_wdt_dev *wdev = file->private_data; + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); - /* Refresh LOAD_TIME. */ - if (len) { - spin_lock(&wdt_lock); - omap_wdt_ping(wdev); - spin_unlock(&wdt_lock); - } - return len; + mutex_lock(&wdev->lock); + omap_wdt_reload(wdev); + mutex_unlock(&wdev->lock); + + return 0; } -static long omap_wdt_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) +static int omap_wdt_set_timeout(struct watchdog_device *wdog, + unsigned int timeout) { - struct omap_wd_timer_platform_data *pdata; - struct omap_wdt_dev *wdev; - u32 rs; - int new_margin, bs; - static const struct watchdog_info ident = { - .identity = "OMAP Watchdog", - .options = WDIOF_SETTIMEOUT, - .firmware_version = 0, - }; - - wdev = file->private_data; - pdata = wdev->dev->platform_data; - - switch (cmd) { - case WDIOC_GETSUPPORT: - return copy_to_user((struct watchdog_info __user *)arg, &ident, - sizeof(ident)); - case WDIOC_GETSTATUS: - return put_user(0, (int __user *)arg); - case WDIOC_GETBOOTSTATUS: - if (!pdata || !pdata->read_reset_sources) - return put_user(0, (int __user *)arg); - rs = pdata->read_reset_sources(); - bs = (rs & (1 << OMAP_MPU_WD_RST_SRC_ID_SHIFT)) ? - WDIOF_CARDRESET : 0; - return put_user(bs, (int __user *)arg); - case WDIOC_KEEPALIVE: - spin_lock(&wdt_lock); - omap_wdt_ping(wdev); - spin_unlock(&wdt_lock); - return 0; - case WDIOC_SETTIMEOUT: - if (get_user(new_margin, (int __user *)arg)) - return -EFAULT; - omap_wdt_adjust_timeout(new_margin); - - spin_lock(&wdt_lock); - omap_wdt_disable(wdev); - omap_wdt_set_timeout(wdev); - omap_wdt_enable(wdev); + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); - omap_wdt_ping(wdev); - spin_unlock(&wdt_lock); - /* Fall */ - case WDIOC_GETTIMEOUT: - return put_user(timer_margin, (int __user *)arg); - default: - return -ENOTTY; - } + mutex_lock(&wdev->lock); + omap_wdt_disable(wdev); + omap_wdt_set_timer(wdev, timeout); + omap_wdt_enable(wdev); + omap_wdt_reload(wdev); + wdog->timeout = timeout; + mutex_unlock(&wdev->lock); + + return 0; } -static const struct file_operations omap_wdt_fops = { - .owner = THIS_MODULE, - .write = omap_wdt_write, - .unlocked_ioctl = omap_wdt_ioctl, - .open = omap_wdt_open, - .release = omap_wdt_release, - .llseek = no_llseek, +static const struct watchdog_info omap_wdt_info = { + .options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING, + .identity = "OMAP Watchdog", +}; + +static const struct watchdog_ops omap_wdt_ops = { + .owner = THIS_MODULE, + .start = omap_wdt_start, + .stop = omap_wdt_stop, + .ping = omap_wdt_ping, + .set_timeout = omap_wdt_set_timeout, }; static int omap_wdt_probe(struct platform_device *pdev) { + struct omap_wd_timer_platform_data *pdata = pdev->dev.platform_data; + bool nowayout = WATCHDOG_NOWAYOUT; + struct watchdog_device *omap_wdt; struct resource *res, *mem; struct omap_wdt_dev *wdev; + u32 rs; int ret; + omap_wdt = devm_kzalloc(&pdev->dev, sizeof(*omap_wdt), GFP_KERNEL); + if (!omap_wdt) + return -ENOMEM; + /* reserve static register mappings */ res = platform_get_resource(pdev, IORESOURCE_MEM, 0); - if (!res) { - ret = -ENOENT; - goto err_get_resource; - } + if (!res) + return -ENOENT; - if (omap_wdt_dev) { - ret = -EBUSY; - goto err_busy; - } + mem = devm_request_mem_region(&pdev->dev, res->start, + resource_size(res), pdev->name); + if (!mem) + return -EBUSY; - mem = request_mem_region(res->start, resource_size(res), pdev->name); - if (!mem) { - ret = -EBUSY; - goto err_busy; - } + wdev = devm_kzalloc(&pdev->dev, sizeof(*wdev), GFP_KERNEL); + if (!wdev) + return -ENOMEM; - wdev = kzalloc(sizeof(struct omap_wdt_dev), GFP_KERNEL); - if (!wdev) { - ret = -ENOMEM; - goto err_kzalloc; - } + wdev->omap_wdt_users = false; + wdev->mem = mem; + wdev->dev = &pdev->dev; + wdev->wdt_trgr_pattern = 0x1234; + mutex_init(&wdev->lock); - wdev->omap_wdt_users = 0; - wdev->mem = mem; - wdev->dev = &pdev->dev; + wdev->base = devm_ioremap(&pdev->dev, res->start, resource_size(res)); + if (!wdev->base) + return -ENOMEM; - wdev->base = ioremap(res->start, resource_size(res)); - if (!wdev->base) { - ret = -ENOMEM; - goto err_ioremap; - } + omap_wdt->info = &omap_wdt_info; + omap_wdt->ops = &omap_wdt_ops; + omap_wdt->min_timeout = TIMER_MARGIN_MIN; + omap_wdt->max_timeout = TIMER_MARGIN_MAX; + + if (timer_margin >= TIMER_MARGIN_MIN && + timer_margin <= TIMER_MARGIN_MAX) + omap_wdt->timeout = timer_margin; + else + omap_wdt->timeout = TIMER_MARGIN_DEFAULT; - platform_set_drvdata(pdev, wdev); + watchdog_set_drvdata(omap_wdt, wdev); + watchdog_set_nowayout(omap_wdt, nowayout); + + platform_set_drvdata(pdev, omap_wdt); pm_runtime_enable(wdev->dev); pm_runtime_get_sync(wdev->dev); - omap_wdt_disable(wdev); - omap_wdt_adjust_timeout(timer_margin); + if (pdata && pdata->read_reset_sources) + rs = pdata->read_reset_sources(); + else + rs = 0; + omap_wdt->bootstatus = (rs & (1 << OMAP_MPU_WD_RST_SRC_ID_SHIFT)) ? + WDIOF_CARDRESET : 0; - wdev->omap_wdt_miscdev.parent = &pdev->dev; - wdev->omap_wdt_miscdev.minor = WATCHDOG_MINOR; - wdev->omap_wdt_miscdev.name = "watchdog"; - wdev->omap_wdt_miscdev.fops = &omap_wdt_fops; + omap_wdt_disable(wdev); - ret = misc_register(&(wdev->omap_wdt_miscdev)); - if (ret) - goto err_misc; + ret = watchdog_register_device(omap_wdt); + if (ret) { + pm_runtime_disable(wdev->dev); + return ret; + } pr_info("OMAP Watchdog Timer Rev 0x%02x: initial timeout %d sec\n", __raw_readl(wdev->base + OMAP_WATCHDOG_REV) & 0xFF, - timer_margin); + omap_wdt->timeout); pm_runtime_put_sync(wdev->dev); - omap_wdt_dev = pdev; - return 0; - -err_misc: - pm_runtime_disable(wdev->dev); - platform_set_drvdata(pdev, NULL); - iounmap(wdev->base); - -err_ioremap: - wdev->base = NULL; - kfree(wdev); - -err_kzalloc: - release_mem_region(res->start, resource_size(res)); - -err_busy: -err_get_resource: - - return ret; } static void omap_wdt_shutdown(struct platform_device *pdev) { - struct omap_wdt_dev *wdev = platform_get_drvdata(pdev); + struct watchdog_device *wdog = platform_get_drvdata(pdev); + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); + mutex_lock(&wdev->lock); if (wdev->omap_wdt_users) { omap_wdt_disable(wdev); pm_runtime_put_sync(wdev->dev); } + mutex_unlock(&wdev->lock); } static int omap_wdt_remove(struct platform_device *pdev) { - struct omap_wdt_dev *wdev = platform_get_drvdata(pdev); - struct resource *res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + struct watchdog_device *wdog = platform_get_drvdata(pdev); + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); pm_runtime_disable(wdev->dev); - if (!res) - return -ENOENT; - - misc_deregister(&(wdev->omap_wdt_miscdev)); - release_mem_region(res->start, resource_size(res)); - platform_set_drvdata(pdev, NULL); - - iounmap(wdev->base); - - kfree(wdev); - omap_wdt_dev = NULL; + watchdog_unregister_device(wdog); return 0; } @@ -386,25 +313,31 @@ static int omap_wdt_remove(struct platform_device *pdev) static int omap_wdt_suspend(struct platform_device *pdev, pm_message_t state) { - struct omap_wdt_dev *wdev = platform_get_drvdata(pdev); + struct watchdog_device *wdog = platform_get_drvdata(pdev); + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); + mutex_lock(&wdev->lock); if (wdev->omap_wdt_users) { omap_wdt_disable(wdev); pm_runtime_put_sync(wdev->dev); } + mutex_unlock(&wdev->lock); return 0; } static int omap_wdt_resume(struct platform_device *pdev) { - struct omap_wdt_dev *wdev = platform_get_drvdata(pdev); + struct watchdog_device *wdog = platform_get_drvdata(pdev); + struct omap_wdt_dev *wdev = watchdog_get_drvdata(wdog); + mutex_lock(&wdev->lock); if (wdev->omap_wdt_users) { pm_runtime_get_sync(wdev->dev); omap_wdt_enable(wdev); - omap_wdt_ping(wdev); + omap_wdt_reload(wdev); } + mutex_unlock(&wdev->lock); return 0; } @@ -437,5 +370,4 @@ module_platform_driver(omap_wdt_driver); MODULE_AUTHOR("George G. Davis"); MODULE_LICENSE("GPL"); -MODULE_ALIAS_MISCDEV(WATCHDOG_MINOR); MODULE_ALIAS("platform:omap_wdt"); |