[Intel-gfx] [PATCH] drm/i915: Allow control of PSR at runtime through debugfs.

[Chris Wilson]

Quoting Maarten Lankhorst (2018-03-14 15:58:32)
> Currently tests modify i915.enable_psr and then do a modeset cycle
> to change PSR. We can write a value to i915_edp_psr_status to force
> a certain value without a modeset.
> 
> To retain compatibility with older userspace, we also still allow
> the override through the module parameter, and add some tracking
> to check whether a debugfs mode is specified.

Is it possible for you to mandate that the process holds the file open
for as long as it wants its value to hold. Then we can automatically
clean up if the process dies; without requiring userspace to dig itself
out of a hole.
-Chris