On Tue, Mar 24, 2020 at 7:35 AM Doug Anderson dianders@chromium.org wrote:
Hi,
On Sun, Mar 22, 2020 at 11:14 PM Kalyan Thota kalyan_t@codeaurora.org wrote:
"The PM core always increments the runtime usage counter before calling the ->suspend() callback and decrements it after calling the ->resume() callback"
DPU and DSI are managed as runtime devices. When suspend is triggered, PM core adds a refcount on all the devices and calls device suspend, since usage count is already incremented, runtime suspend was not getting called and it kept the clocks on which resulted in target not entering into XO shutdown.
Add changes to manage runtime devices during pm sleep.
Changes in v1:
- Remove unnecessary checks in the function _dpu_kms_disable_dpu (Rob Clark).
I'm wondering what happened with my feedback on v1, AKA:
https://lore.kernel.org/r/CAD=FV=VxzEV40g+ieuEN+7o=34+wM8MHO8o7T5zA1Yosx7SVW...
Maybe you didn't see it? ...or if you or Rob think I'm way off base (always possible) then please tell me so.
At least w/ the current patch, disable_dpu should not be called for screen-off (although I'd hope if all the screens are off the device would suspend). But I won't claim to be a pm expert.. so not really sure if this is the best approach or not. I don't think our arrangement of sub-devices under a parent is completely abnormal, so it does feel like there should be a simpler solution..
BR, -R