diff mbox series

[v3] PM: sleep: core: Clear is_prepared if both no_pm_callbacks and direct_complete is set

Message ID 20250224070049.3338646-1-xu.yang_2@nxp.com (mailing list archive)
State New
Headers show
Series [v3] PM: sleep: core: Clear is_prepared if both no_pm_callbacks and direct_complete is set | expand

Commit Message

Xu Yang Feb. 24, 2025, 7 a.m. UTC 
Currently, if power.no_callbacks is true for a device, device_prepare()
will also set power.direct_complete to true. When device_resume() check
power.direct_complete, setting power.is_prepared will be skipped if it
can directly complete. This will cause a warning when add new devices
during resume() stage.

Although power.is_prepared should be cleared in complete() state, commit
(f76b168b6f11 PM: Rename dev_pm_info.in_suspend to is_prepared) allow
clear it in earlier resume() stage. However, we need also set is_prepared
to false if both power.no_callbacks and power.direct_complete are true.

Take USB as example:
The usb_interface is such a device which setting power.no_callbacks to
true. Then if the user call usb_set_interface() during resume() stage,
the kernel will print below warning since the system will create and
add ep devices.

[  186.461414] usb 1-1: reset high-speed USB device number 3 using ci_hdrc
[  187.102681]  ep_81: PM: parent 1-1:1.1 should not be sleeping
[  187.105010] PM: resume devices took 0.936 seconds

Suggested-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Xu Yang <xu.yang_2@nxp.com>

---
v3: combined checking no_pm_callbacks and direct_complete
v2: clear is_prepared before check syscore as suggested by Rafael
---
 drivers/base/power/main.c | 7 +++++++
 1 file changed, 7 insertions(+)
diff mbox series

Patch

diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index dffa2aa1ba7d..b9b1fd43427d 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -930,6 +930,13 @@  static void device_resume(struct device *dev, pm_message_t state, bool async)
 		goto Complete;
 
 	if (dev->power.direct_complete) {
+		/*
+		 * Allow new children to be added in the resume stage for
+		 * devices with no PM callbacks and can be completed directly.
+		 */
+		if (dev->power.no_pm_callbacks)
+			dev->power.is_prepared = false;
+
 		/* Match the pm_runtime_disable() in device_suspend(). */
 		pm_runtime_enable(dev);
 		goto Complete;