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authorMark Brown <broonie@opensource.wolfsonmicro.com>2010-03-02 12:23:46 +0100
committerJean Delvare <khali@linux-fr.org>2010-03-02 12:23:46 +0100
commit6de468ae2df0ee6fbee668d946811638b57361f6 (patch)
treec0b43c2d3bb8c89c012cbfeb185ff03ad3d86326 /drivers/i2c
parent927ab2f80745ec26f1e83e6ca15a5b29e134c8e5 (diff)
downloadlinux-6de468ae2df0ee6fbee668d946811638b57361f6.tar.bz2
i2c: Hook up runtime PM support
Allow I2C drivers to make use of the runtime PM framework by adding bus implementations of the runtime PM operations. These simply immediately suspend when the device is idle. The runtime PM framework provides drivers with off the shelf refcounts for enables and sysfs control for managing runtime suspend from userspace so is useful even without meaningful input from the bus. Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/i2c-core.c50
1 files changed, 50 insertions, 0 deletions
diff --git a/drivers/i2c/i2c-core.c b/drivers/i2c/i2c-core.c
index 10be7b5fbe97..4131698008b9 100644
--- a/drivers/i2c/i2c-core.c
+++ b/drivers/i2c/i2c-core.c
@@ -34,6 +34,7 @@
#include <linux/hardirq.h>
#include <linux/irqflags.h>
#include <linux/rwsem.h>
+#include <linux/pm_runtime.h>
#include <asm/uaccess.h>
#include "i2c-core.h"
@@ -184,6 +185,52 @@ static int i2c_device_pm_resume(struct device *dev)
#define i2c_device_pm_resume NULL
#endif
+#ifdef CONFIG_PM_RUNTIME
+static int i2c_device_runtime_suspend(struct device *dev)
+{
+ const struct dev_pm_ops *pm;
+
+ if (!dev->driver)
+ return 0;
+ pm = dev->driver->pm;
+ if (!pm || !pm->runtime_suspend)
+ return 0;
+ return pm->runtime_suspend(dev);
+}
+
+static int i2c_device_runtime_resume(struct device *dev)
+{
+ const struct dev_pm_ops *pm;
+
+ if (!dev->driver)
+ return 0;
+ pm = dev->driver->pm;
+ if (!pm || !pm->runtime_resume)
+ return 0;
+ return pm->runtime_resume(dev);
+}
+
+static int i2c_device_runtime_idle(struct device *dev)
+{
+ const struct dev_pm_ops *pm = NULL;
+ int ret;
+
+ if (dev->driver)
+ pm = dev->driver->pm;
+ if (pm && pm->runtime_idle) {
+ ret = pm->runtime_idle(dev);
+ if (ret)
+ return ret;
+ }
+
+ return pm_runtime_suspend(dev);
+}
+#else
+#define i2c_device_runtime_suspend NULL
+#define i2c_device_runtime_resume NULL
+#define i2c_device_runtime_idle NULL
+#endif
+
static int i2c_device_suspend(struct device *dev, pm_message_t mesg)
{
struct i2c_client *client = i2c_verify_client(dev);
@@ -251,6 +298,9 @@ static const struct attribute_group *i2c_dev_attr_groups[] = {
static const struct dev_pm_ops i2c_device_pm_ops = {
.suspend = i2c_device_pm_suspend,
.resume = i2c_device_pm_resume,
+ .runtime_suspend = i2c_device_runtime_suspend,
+ .runtime_resume = i2c_device_runtime_resume,
+ .runtime_idle = i2c_device_runtime_idle,
};
struct bus_type i2c_bus_type = {