Enable extra state checking for runtime PM

configname: CONFIG_DRM_I915_DEBUG_RUNTIME_PM

Linux Kernel Configuration
└─>Device Drivers
└─>Graphics support
└─>drm/i915 Debugging
└─>Enable extra state checking for runtime PM
In linux kernel since version 3.10 (release Date: 2013-06-30)  
Choose this option to turn on extra state checking for the
runtime PM functionality. This may introduce overhead during
driver loading, suspend and resume operations.

Recommended for driver developers only.

If in doubt, say "N"