| Message ID | 20250213105840.2864654-1-xu.yang_2@nxp.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] PM: sleep: core: Clear is_prepared if no_pm_callbacks is true before checking power.syscore | expand |
On Thu, Feb 13, 2025 at 11:58 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 before checking syscore if the device has no pm callbacks. > > 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 > > Signed-off-by: Xu Yang <xu.yang_2@nxp.com> > > --- > v2: clear is_prepared before check syscore as suggested by Rafael > --- > drivers/base/power/main.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c > index 40e1d8d8a589..5e69cfaec661 100644 > --- a/drivers/base/power/main.c > +++ b/drivers/base/power/main.c > @@ -926,6 +926,9 @@ static void device_resume(struct device *dev, pm_message_t state, bool async) > TRACE_DEVICE(dev); > TRACE_RESUME(0); > > + if (dev->power.no_pm_callbacks) > + dev->power.is_prepared = false; > + > if (dev->power.syscore) > goto Complete; > > -- As I've already said in the other thread, my initial feedback was based on an oversimplified view of this code, and the problem will need to be addressed differently. Sorry about that.
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c index 40e1d8d8a589..5e69cfaec661 100644 --- a/drivers/base/power/main.c +++ b/drivers/base/power/main.c @@ -926,6 +926,9 @@ static void device_resume(struct device *dev, pm_message_t state, bool async) TRACE_DEVICE(dev); TRACE_RESUME(0); + if (dev->power.no_pm_callbacks) + dev->power.is_prepared = false; + if (dev->power.syscore) 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 before checking syscore if the device has no pm callbacks. 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 Signed-off-by: Xu Yang <xu.yang_2@nxp.com> --- v2: clear is_prepared before check syscore as suggested by Rafael --- drivers/base/power/main.c | 3 +++ 1 file changed, 3 insertions(+)