driver core/PM: Set power.no_callbacks along with power.no_pm

commit c2ce245 upstream.

Devices with power.no_pm set are not expected to need any power
management at all, so modify device_set_pm_not_required() to set
power.no_callbacks for them too in case runtime PM will be enabled
for any of them (which in principle may be done for convenience if
such a device participates in a dependency chain).

Since device_set_pm_not_required() must be called before device_add()
or it would not have any effect, it can update power.no_callbacks
without locking, unlike pm_runtime_no_callbacks() that can be called
after registering the target device.

Signed-off-by: Rafael J. Wysocki <[email protected]>
Cc: stable <[email protected]>
Reviewed-by: Sudeep Holla <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: rafaeljw

include/linux/device.h

@@ -873,6 +873,9 @@ static inline bool device_pm_not_required(struct device *dev)
 static inline void device_set_pm_not_required(struct device *dev)
 {
 	dev->power.no_pm = true;
+#ifdef CONFIG_PM
+	dev->power.no_callbacks = true;
+#endif
 }
 
 static inline void dev_pm_syscore_device(struct device *dev, bool val)