i915_suspend() is called from the DRM legacy S3 suspend/S4 freeze paths
and the switcheroo suspend path. For switcheroo we only ever need to
perform a full suspend (PM_EVENT_SUSPEND) and for the DRM legacy path
we can handle the S4 freeze (PM_EVENT_FREEZE) the same way as S3
suspend. The only difference atm between suspend and freeze is that
during freeze we don't disable the PCI device, but there is no reason
why we can't do so. So unify the two cases to reduce complexity.
Note that for the DRM legacy case the thaw event is not handled, so
we disable the display before creating the hibernation image and it
won't get re-enabled until reboot. We could fix this leaving the
display enabled for the image creation/writing (if we care enough
about UMS), but this can be done as a follow-up.
Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
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