With the recent addition of locking checks in
commit 62ff94a549
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
AuthorDate: Thu Jan 23 22:18:47 2014 +0100
drm/crtc-helper: remove LOCKING from kerneldoc
drm_add_edid_modes started to WARN about the mode_config.mutex not
being held in the lvds and dp initialization code.
Now since this is init code locking is fairly redudant if it wouldn't
be for the drm core registering sysfs files a bit early. And the
locking WARNINGs nicely enforce that indeed all access to the mode
lists are properly protected. And a full audit shows that only i915
and gma500 touch the modes lists at init time.
Hence I've opted to wrap up this entire mode detection sequence for
fixed panels with the mode_config mutex for both lvds and edp outputs.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
************************************************************
* 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
4da98541d8