@@ -371,6 +371,7 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
if (ret)
goto exit_probe;
+ dev_pm_use_rpm_sleep(&pdev->dev);
return ret;
exit_probe:
@@ -412,15 +413,6 @@ static const struct of_device_id dw_i2c_of_match[] = {
MODULE_DEVICE_TABLE(of, dw_i2c_of_match);
#endif
-#ifdef CONFIG_PM_SLEEP
-static int dw_i2c_plat_prepare(struct device *dev)
-{
- return pm_runtime_suspended(dev);
-}
-#else
-#define dw_i2c_plat_prepare NULL
-#endif
-
#ifdef CONFIG_PM
static int dw_i2c_plat_runtime_suspend(struct device *dev)
{
@@ -433,7 +425,7 @@ static int dw_i2c_plat_runtime_suspend(struct device *dev)
return 0;
}
-static int dw_i2c_plat_resume(struct device *dev)
+static int dw_i2c_plat_runtime_resume(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct dw_i2c_dev *i_dev = platform_get_drvdata(pdev);
@@ -444,19 +436,11 @@ static int dw_i2c_plat_resume(struct device *dev)
return 0;
}
-#ifdef CONFIG_PM_SLEEP
-static int dw_i2c_plat_suspend(struct device *dev)
-{
- pm_runtime_resume(dev);
- return dw_i2c_plat_runtime_suspend(dev);
-}
-#endif
-
static const struct dev_pm_ops dw_i2c_dev_pm_ops = {
- .prepare = dw_i2c_plat_prepare,
- SET_SYSTEM_SLEEP_PM_OPS(dw_i2c_plat_suspend, dw_i2c_plat_resume)
+ SET_LATE_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
SET_RUNTIME_PM_OPS(dw_i2c_plat_runtime_suspend,
- dw_i2c_plat_resume,
+ dw_i2c_plat_runtime_resume,
NULL)
};
Currently the device is runtime resumed in the i2c-dw-plat driver's ->suspend() callback, which is needed to manage system sleep properly. The particular reason for the runtime resume is because the PM core may unset the direct_complete flag for a parent device, in case its child device are being system suspended before. This leads to that the i2c-dw-plat driver's ->suspend() callback can be invoked when the device is runtime suspended. Runtime resuming the device in this scenario may be unnecessary, in case when the device is already in its proper lower power state for system sleep. This behaviour increases the time it takes to put the device into low power state, but means also a waste of power. Let's fix the behaviour by deploying the runtime PM centric path for system sleep, via assigning the pm_runtime_force_suspend|resume() helpers as the system sleep callbacks for the i2c-dw-plat driver. We must also inform the PM core and the ACPI PM domain that we are now using the runtime PM centric path, therefore we call dev_pm_use_rpm_sleep() during ->probe(). While deploying the runtime PM centric path, the ->prepare() callback becomes redundant, so let's drop it. Along with these improvements, of course we also get the other regular benefits one get when deploying the runtime PM centric path. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> --- Changes in v3: - Use dev_pm_use_rpm_sleep() instead of the earlier acpi_disable_direct_complete() from v2. - Updated changelog. --- drivers/i2c/busses/i2c-designware-platdrv.c | 26 +++++--------------------- 1 file changed, 5 insertions(+), 21 deletions(-) -- 2.7.4