From 0503add9d251db22ba2f610fb8d9b7743a9786da Mon Sep 17 00:00:00 2001 From: Paul Walmsley Date: Thu, 10 Mar 2011 22:40:05 -0700 Subject: Watchdog: omap_wdt: add fine grain runtime-pm The omap_wdt should only be in full active state when the registers are being accessed. Otherwise the device can be on lower power mode. This patch is based on a patch created by Kalle Jokiniemi: https://patchwork.kernel.org/patch/618231/ which is itself based on a patch created by Atal Shargorodsky: http://lkml.org/lkml/2009/3/10/266. Signed-off-by: Paul Walmsley Signed-off-by: Kalle Jokiniemi Tested-by: Kalle Jokiniemi Cc: Wim Van Sebroeck Acked-by: Wim Van Sebroeck Acked-by: Kevin Hilman --- drivers/watchdog/omap_wdt.c | 25 +++++++++++++++++++++++-- 1 file changed, 23 insertions(+), 2 deletions(-) (limited to 'drivers/watchdog') diff --git a/drivers/watchdog/omap_wdt.c b/drivers/watchdog/omap_wdt.c index 3dd4971160ef..2b4acb86c191 100644 --- a/drivers/watchdog/omap_wdt.c +++ b/drivers/watchdog/omap_wdt.c @@ -124,6 +124,8 @@ static void omap_wdt_set_timeout(struct omap_wdt_dev *wdev) u32 pre_margin = GET_WLDR_VAL(timer_margin); void __iomem *base = wdev->base; + pm_runtime_get_sync(wdev->dev); + /* just count up at 32 KHz */ while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x04) cpu_relax(); @@ -131,6 +133,8 @@ static void omap_wdt_set_timeout(struct omap_wdt_dev *wdev) __raw_writel(pre_margin, base + OMAP_WATCHDOG_LDR); while (__raw_readl(base + OMAP_WATCHDOG_WPS) & 0x04) cpu_relax(); + + pm_runtime_put_sync(wdev->dev); } /* @@ -160,6 +164,8 @@ static int omap_wdt_open(struct inode *inode, struct file *file) omap_wdt_ping(wdev); /* trigger loading of new timeout value */ omap_wdt_enable(wdev); + pm_runtime_put_sync(wdev->dev); + return nonseekable_open(inode, file); } @@ -171,6 +177,7 @@ static int omap_wdt_release(struct inode *inode, struct file *file) * Shut off the timer unless NOWAYOUT is defined. */ #ifndef CONFIG_WATCHDOG_NOWAYOUT + pm_runtime_get_sync(wdev->dev); omap_wdt_disable(wdev); @@ -190,9 +197,11 @@ static ssize_t omap_wdt_write(struct file *file, const char __user *data, /* Refresh LOAD_TIME. */ if (len) { + pm_runtime_get_sync(wdev->dev); spin_lock(&wdt_lock); omap_wdt_ping(wdev); spin_unlock(&wdt_lock); + pm_runtime_put_sync(wdev->dev); } return len; } @@ -224,15 +233,18 @@ static long omap_wdt_ioctl(struct file *file, unsigned int cmd, return put_user(omap_prcm_get_reset_sources(), (int __user *)arg); case WDIOC_KEEPALIVE: + pm_runtime_get_sync(wdev->dev); spin_lock(&wdt_lock); omap_wdt_ping(wdev); spin_unlock(&wdt_lock); + pm_runtime_put_sync(wdev->dev); return 0; case WDIOC_SETTIMEOUT: if (get_user(new_margin, (int __user *)arg)) return -EFAULT; omap_wdt_adjust_timeout(new_margin); + pm_runtime_get_sync(wdev->dev); spin_lock(&wdt_lock); omap_wdt_disable(wdev); omap_wdt_set_timeout(wdev); @@ -240,6 +252,7 @@ static long omap_wdt_ioctl(struct file *file, unsigned int cmd, omap_wdt_ping(wdev); spin_unlock(&wdt_lock); + pm_runtime_put_sync(wdev->dev); /* Fall */ case WDIOC_GETTIMEOUT: return put_user(timer_margin, (int __user *)arg); @@ -345,8 +358,11 @@ static void omap_wdt_shutdown(struct platform_device *pdev) { struct omap_wdt_dev *wdev = platform_get_drvdata(pdev); - if (wdev->omap_wdt_users) + if (wdev->omap_wdt_users) { + pm_runtime_get_sync(wdev->dev); omap_wdt_disable(wdev); + pm_runtime_put_sync(wdev->dev); + } } static int __devexit omap_wdt_remove(struct platform_device *pdev) @@ -381,8 +397,11 @@ static int omap_wdt_suspend(struct platform_device *pdev, pm_message_t state) { struct omap_wdt_dev *wdev = platform_get_drvdata(pdev); - if (wdev->omap_wdt_users) + if (wdev->omap_wdt_users) { + pm_runtime_get_sync(wdev->dev); omap_wdt_disable(wdev); + pm_runtime_put_sync(wdev->dev); + } return 0; } @@ -392,8 +411,10 @@ static int omap_wdt_resume(struct platform_device *pdev) struct omap_wdt_dev *wdev = platform_get_drvdata(pdev); if (wdev->omap_wdt_users) { + pm_runtime_get_sync(wdev->dev); omap_wdt_enable(wdev); omap_wdt_ping(wdev); + pm_runtime_put_sync(wdev->dev); } return 0; -- cgit v1.2.3