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372835a852
Atm the crtc helper implementation of set_config has really inconsisten semantics: If just an fb update is good enough, dpms state will be left as-is, but if we do a full modeset we force everything to dpms on. This change has already been applied to the i915 modeset code in commite3de42b684Author: Imre Deak <imre.deak@intel.com> Date: Fri May 3 19:44:07 2013 +0200 drm/i915: force full modeset if the connector is in DPMS OFF mode which according to Greg KH seems to aim for a new record in most Bugzilla: links in a commit message. The history of this dpms forcing is pretty interesting. This patch here is an almost-revert of commit811aaa55baAuthor: Keith Packard <keithp@keithp.com> Date: Thu Feb 3 16:57:28 2011 -0800 drm: Only set DPMS ON when actually configuring a mode which fixed the bug of trying to dpms on disabled outputs, but introduced the new discrepancy between an fb update only and full modesets. The actual introduction of this goes back to commitbf9dc102e2Author: Keith Packard <keithp@keithp.com> Date: Fri Nov 26 10:45:58 2010 -0800 drm: Set connector DPMS status to ON in drm_crtc_helper_set_config And if you'd dig around in the i915 driver code there's even more fun around forcing dpms on and losing our heads and temper of the resulting inconsistencies. Especially the DP re-training code had tons of funny stuff in it. Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Dave Airlie <airlied@redhat.com>
************************************************************
* For the very latest on DRI development, please see: *
* http://dri.freedesktop.org/ *
************************************************************
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