From f492ef42a0e87818b097a8bcde926e9ad09ff1f1 Mon Sep 17 00:00:00 2001 From: Daniel Vetter Date: Mon, 2 Apr 2012 08:36:57 -0700 Subject: UBUNTU: SAUCE: (drop after 3.5) drm/i915: reinstate GM45 TV detection fix BugLink: http://bugs.launchpad.net/bugs/638939 cherry picked from drm-intel-next-queue This reverts commmit d4b74bf07873da2e94219a7b67a334fc1c3ce649 which reverted the origin fix fb8b5a39b6310379d7b54c0c7113703a8eaf4a57. We have at least 3 different bug reports that this fixes things and no indication what is exactly wrong with this. So try again. To make matters slightly more fun, the commit itself was cc: stable whereas the revert has not been. According to Peter Clifton he discussed this with Zhao Yakui and this seems to be in contradiction of the GM45 PRM, but rumours have it that this is how the BIOS does it ... let's see. Reviewed-by: Rodrigo Vivi Tested-by: Peter Clifton Cc: Zhao Yakui Cc: Dave Airlie Cc: Eric Anholt Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=16236 Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=25913 Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=14792 Signed-Off-by: Daniel Vetter Signed-off-by: Brad Figg Signed-off-by: Tim Gardner --- drivers/gpu/drm/i915/intel_tv.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_tv.c b/drivers/gpu/drm/i915/intel_tv.c index 05f765ef546..ca12c709f3e 100644 --- a/drivers/gpu/drm/i915/intel_tv.c +++ b/drivers/gpu/drm/i915/intel_tv.c @@ -1153,6 +1153,15 @@ intel_tv_detect_type(struct intel_tv *intel_tv, DAC_B_0_7_V | DAC_C_0_7_V); + + /* + * The TV sense state should be cleared to zero on cantiga platform. Otherwise + * the TV is misdetected. This is hardware requirement. + */ + if (IS_GM45(dev)) + tv_dac &= ~(TVDAC_STATE_CHG_EN | TVDAC_A_SENSE_CTL | + TVDAC_B_SENSE_CTL | TVDAC_C_SENSE_CTL); + I915_WRITE(TV_CTL, tv_ctl); I915_WRITE(TV_DAC, tv_dac); POSTING_READ(TV_DAC); -- cgit v1.2.3