PM / runtime: Allow no callbacks in pm_runtime_force_suspend|resume()

The pm_runtime_force_suspend|resume() helpers currently requires the device
to at some level (PM domain, bus, etc), have the ->runtime_suspend|resume()
callbacks assigned for it, else -ENOSYS is returned as an error.

However, there are no reason for this requirement, so let's simply remove
it by allowing these callbacks to be NULL.

Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/base/power/runtime.c b/drivers/base/power/runtime.c
index cb5e48b..8bef3cb 100644 (file)
--- a/drivers/base/power/runtime.c
+++ b/drivers/base/power/runtime.c
@@ -1640,7 +1640,7 @@ static bool pm_runtime_need_not_resume(struct device *dev)
 int pm_runtime_force_suspend(struct device *dev)
 {
        int (*callback)(struct device *);
-       int ret = 0;
+       int ret;
 
        pm_runtime_disable(dev);
        if (pm_runtime_status_suspended(dev))
@@ -1648,12 +1648,7 @@ int pm_runtime_force_suspend(struct device *dev)
 
        callback = RPM_GET_CALLBACK(dev, runtime_suspend);
 
-       if (!callback) {
-               ret = -ENOSYS;
-               goto err;
-       }
-
-       ret = callback(dev);
+       ret = callback ? callback(dev) : 0;
        if (ret)
                goto err;
 
@@ -1704,7 +1699,7 @@ int pm_runtime_force_resume(struct device *dev)
 
        callback = RPM_GET_CALLBACK(dev, runtime_resume);
 
-       ret = callback ? callback(dev) : -ENOSYS;
+       ret = callback ? callback(dev) : 0;
        if (ret) {
                pm_runtime_set_suspended(dev);
                goto out;