drm/edid: Add secondary GTF curve support
authorAdam Jackson <ajax@redhat.com>
Mon, 29 Mar 2010 21:43:30 +0000 (21:43 +0000)
committerDave Airlie <airlied@redhat.com>
Tue, 6 Apr 2010 00:40:25 +0000 (10:40 +1000)
commit7a37435008b0ffea2442eb1134ddd4adeea81e19
treecb0f68ab38d1a6572a913857c67e782ca34ad99c
parent7ca6adb37918db21d076a489c6c39490fb34264e
drm/edid: Add secondary GTF curve support

Before CVT-R, some monitors would advertise support for an alternative
GTF formula with lower blanking intervals.  Correctly identify such
monitors, and use the alternative formula when generating modes for
them.

Note that we only do this for "standard" timing descriptors (tuples of
hsize in characters / aspect ratio / vertical refresh).  Range-based
mode lists still only refer to the primary GTF curve.  It would be
possible to do better for the latter case, but monitors are required to
support the primary curve over the entire advertised range, so all it
would win you is a lower pixel clock and therefore possibly better image
quality on analog links.

Signed-off-by: Adam Jackson <ajax@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
drivers/gpu/drm/drm_edid.c
drivers/gpu/drm/drm_modes.c
include/drm/drm_crtc.h