From: Rob Clark robdclark@chromium.org
Because system suspend uses pm_runtime_force_suspend() we can't rely runpm refcnt's to protect us if the GPU is active, etc. Fortunately *usually* the GPU is idle when system suspend is triggered. But that isn't quite good enough.
The first patch attempts to block for a modest amount of time until GPU is idle (and failing that, returns -EBUSY). We could have taken a slightly easier approach and just returned -EBUSY if GPU is not idle, but that would cause system suspend to fail. And no one likes pulling a hot laptop out of their backpack.
The second patch avoids getting devfreq callbacks after suspend, since pm_runtime_force_suspend() breaks the pm_runtime_get_if_in_use() tricks used to deal with devfreq callbacks while suspended.
Rob Clark (2): drm/msm/gpu: Wait for idle before suspending drm/msm/gpu: Cancel idle/boost work on suspend
drivers/gpu/drm/msm/adreno/adreno_device.c | 18 ++++++++++++++++++ drivers/gpu/drm/msm/msm_gpu.c | 3 +++ drivers/gpu/drm/msm/msm_gpu.h | 3 +++ drivers/gpu/drm/msm/msm_gpu_devfreq.c | 21 +++++++++++++++++++-- 4 files changed, 43 insertions(+), 2 deletions(-)