DRM: i915: add mode setting support

This commit adds i915 driver support for the DRM mode setting APIs.
Currently, VGA, LVDS, SDVO DVI & VGA, TV and DVO LVDS outputs are
supported.  HDMI, DisplayPort and additional SDVO output support will
follow.

Support for the mode setting code is controlled by the new 'modeset'
module option.  A new config option, CONFIG_DRM_I915_KMS controls the
default behavior, and whether a PCI ID list is built into the module for
use by user level module utilities.

Note that if mode setting is enabled, user level drivers that access
display registers directly or that don't use the kernel graphics memory
manager will likely corrupt kernel graphics memory, disrupt output
configuration (possibly leading to hangs and/or blank displays), and
prevent panic/oops messages from appearing.  So use caution when
enabling this code; be sure your user level code supports the new
interfaces.

A new SysRq key, 'g', provides emergency support for switching back to
the kernel's framebuffer console; which is useful for testing.

Co-authors: Dave Airlie <airlied@linux.ie>, Hong Liu <hong.liu@intel.com>

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 11 insertions, 0 deletions

diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
index a8b33c2ec8d2..5f26d6c840de 100644
--- a/drivers/gpu/drm/Kconfig
+++ b/drivers/gpu/drm/Kconfig
@@ -76,6 +76,17 @@ config DRM_I915
 
 endchoice
 
+config DRM_I915_KMS
+        bool "Enable modesetting on intel by default"
+        depends on DRM_I915
+        help
+        Choose this option if you want kernel modesetting enabled by default,
+        and you have a new enough userspace to support this. Running old
+        userspaces with this enabled will cause pain.  Note that this causes
+        the driver to bind to PCI devices, which precludes loading things
+        like intelfb.
+
+
 config DRM_MGA
         tristate "Matrox g200/g400"
         depends on DRM