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When we suspend we turn everything off so the pps should be idle, and we also (or at least should) disable all power wells which will reset the power sequencer port assignment. So when we resume all power sequencers should be in their reset state. However it's at least theoretically possible that the BIOS would touch the power seuqencer(s), so to be safe we ought to read out the current port assignment like we do at driver init time. To do that we can simply call vlv_initial_power_sequencer_setup() from the encoder ->reset() hook before calling intel_edp_panel_vdd_sanitize(). There's no danger or clobbering the pps delays since we now have those stored within intel_dp and we don't change them once initialized. This will make sure that the vdd state gets correctly tracked post-resume in case the BIOS enabled it. We need to shuffle things around a bit to get the locking right, and while at it, make intel_edp_panel_vdd_sanitize() static and move it around a bit to avoid a forward declaration. Cc: Imre Deak <imre.deak@intel.com> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Reviewed-by: Imre Deak <imre.deak@intel.com> Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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* For the very latest on DRI development, please see: *
* http://dri.freedesktop.org/ *
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The Direct Rendering Manager (drm) is a device-independent kernel-level
device driver that provides support for the XFree86 Direct Rendering
Infrastructure (DRI).
The DRM supports the Direct Rendering Infrastructure (DRI) in four major
ways:
1. The DRM provides synchronized access to the graphics hardware via
the use of an optimized two-tiered lock.
2. The DRM enforces the DRI security policy for access to the graphics
hardware by only allowing authenticated X11 clients access to
restricted regions of memory.
3. The DRM provides a generic DMA engine, complete with multiple
queues and the ability to detect the need for an OpenGL context
switch.
4. The DRM is extensible via the use of small device-specific modules
that rely extensively on the API exported by the DRM module.
Documentation on the DRI is available from:
http://dri.freedesktop.org/wiki/Documentation
http://sourceforge.net/project/showfiles.php?group_id=387
http://dri.sourceforge.net/doc/
For specific information about kernel-level support, see:
The Direct Rendering Manager, Kernel Support for the Direct Rendering
Infrastructure
http://dri.sourceforge.net/doc/drm_low_level.html
Hardware Locking for the Direct Rendering Infrastructure
http://dri.sourceforge.net/doc/hardware_locking_low_level.html
A Security Analysis of the Direct Rendering Infrastructure
http://dri.sourceforge.net/doc/security_low_level.html