Messages in this thread Patch in this message | | | Date | Wed, 01 Apr 2020 15:02:21 +0530 | From | kalyan_t@codeauro ... | Subject | Re: [PATCH] drm/msm/dpu: ensure device suspend happens during PM sleep |
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On 2020-03-31 21:30, Doug Anderson wrote: > Hi, > > On Tue, Mar 31, 2020 at 6:58 AM 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 force suspend on runtime devices during pm sleep. >> >> Changes in v1: >> - Remove unnecessary checks in the function >> _dpu_kms_disable_dpu (Rob Clark). >> >> Changes in v2: >> - Avoid using suspend_late to reset the usagecount >> as suspend_late might not be called during suspend >> call failures (Doug). >> >> Changes in v3: >> - Use force suspend instead of managing device usage_count >> via runtime put and get API's to trigger callbacks (Doug). >> >> Signed-off-by: Kalyan Thota <kalyan_t@codeaurora.org> >> --- >> drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c | 2 ++ >> drivers/gpu/drm/msm/dsi/dsi.c | 2 ++ >> drivers/gpu/drm/msm/msm_drv.c | 4 ++++ >> 3 files changed, 8 insertions(+) > > This looks much saner to me. Thanks! I assume it still works fine > for you? I'm still no expert on how all the pieces of DRM drivers > work together, but at least there's not a bunch of strange fiddling > with pm_runtime state and hopefully it will avoid weird corner > cases... > --- Yes, verified the change on trogdor device, and display can suspend with the change. > >> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c >> b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c >> index ce19f1d..b886d9d 100644 >> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c >> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_kms.c >> @@ -1123,6 +1123,8 @@ static int __maybe_unused >> dpu_runtime_resume(struct device *dev) >> >> static const struct dev_pm_ops dpu_pm_ops = { >> SET_RUNTIME_PM_OPS(dpu_runtime_suspend, dpu_runtime_resume, >> NULL) >> + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, >> + pm_runtime_force_resume) >> }; >> >> static const struct of_device_id dpu_dt_match[] = { >> diff --git a/drivers/gpu/drm/msm/dsi/dsi.c >> b/drivers/gpu/drm/msm/dsi/dsi.c >> index 55ea4bc2..62704885 100644 >> --- a/drivers/gpu/drm/msm/dsi/dsi.c >> +++ b/drivers/gpu/drm/msm/dsi/dsi.c >> @@ -161,6 +161,8 @@ static int dsi_dev_remove(struct platform_device >> *pdev) >> >> static const struct dev_pm_ops dsi_pm_ops = { >> SET_RUNTIME_PM_OPS(msm_dsi_runtime_suspend, >> msm_dsi_runtime_resume, NULL) >> + SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend, >> + pm_runtime_force_resume) >> }; >> >> static struct platform_driver dsi_driver = { >> diff --git a/drivers/gpu/drm/msm/msm_drv.c >> b/drivers/gpu/drm/msm/msm_drv.c >> index 7d985f8..2b8c99c 100644 >> --- a/drivers/gpu/drm/msm/msm_drv.c >> +++ b/drivers/gpu/drm/msm/msm_drv.c >> @@ -1051,6 +1051,8 @@ static int msm_pm_suspend(struct device *dev) >> return ret; >> } >> >> + pm_runtime_force_suspend(dev); > > nit: check return value of pm_runtime_force_suspend()? > > >> + >> return 0; >> } >> >> @@ -1063,6 +1065,8 @@ static int msm_pm_resume(struct device *dev) >> if (WARN_ON(!priv->pm_state)) >> return -ENOENT; >> >> + pm_runtime_force_resume(dev); > > nit: check return value of pm_runtime_force_resume()? > > > -Doug
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