| Message ID | 20250224070049.3338646-1-xu.yang_2@nxp.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v3] PM: sleep: core: Clear is_prepared if both no_pm_callbacks and direct_complete is set | expand |
On Mon, Feb 24, 2025 at 7:59 AM Xu Yang <xu.yang_2@nxp.com> wrote: > > 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 --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; > -- Applied as 6.15 material under a new subject and with edits in the changelog. Thanks!
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;
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(+)