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 <paul@pwsan.com>
Signed-off-by: Kalle Jokiniemi <kalle.jokiniemi@nokia.com>
Tested-by: Kalle Jokiniemi <kalle.jokiniemi@nokia.com>
Cc: Wim Van Sebroeck <wim@iguana.be>
Acked-by: Wim Van Sebroeck <wim@iguana.be>
Acked-by: Kevin Hilman <khilman@ti.com>
This commit is contained in:
Paul Walmsley 2011-03-10 22:40:05 -07:00
parent 0dde52a9f5
commit 0503add9d2

View file

@ -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;