[PATCH 4.0 66/72] drm/radeon: adjust pll when audio is not enabled

Greg Kroah-Hartman
2015-05-11T18:53:38Z

From: Alex Deucher <alexander.deucher@amd.com>

commit 7fe04d6fa824ccea704535a597dc417c8687f990 upstream.

Fixes display problems with some monitors when audio
is not enabled.

Bugs:
https://bugs.freedesktop.org/show_bug.cgi?id=89505
https://bugzilla.kernel.org/show_bug.cgi?id=94171
Plus several reports on IRC.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/gpu/drm/radeon/atombios_crtc.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/gpu/drm/radeon/atombios_crtc.c
+++ b/drivers/gpu/drm/radeon/atombios_crtc.c
@@ -580,6 +580,9 @@ static u32 atombios_adjust_pll(struct dr
else
radeon_crtc->pll_flags |= RADEON_PLL_PREFER_LOW_REF_DIV;

+ /* if there is no audio, set MINM_OVER_MAXP */
+ if (!drm_detect_monitor_audio(radeon_connector_edid(connector)))
+ radeon_crtc->pll_flags |= RADEON_PLL_PREFER_MINM_OVER_MAXP;
if (rdev->family < CHIP_RV770)
radeon_crtc->pll_flags |= RADEON_PLL_PREFER_MINM_OVER_MAXP;
/* use frac fb div on APUs */