drm/i915: Add support for limited color range of broadcast outputs
In order to prevent "crushed blacks" on TVs, the range of the RGB output
may be limited to 16-235. This used to be available through Xorg under
the "Broadcast RGB" option, so reintroduce support for KMS.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=34543
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c
index 7ffb324..3216adc 100644
--- a/drivers/gpu/drm/i915/intel_dp.c
+++ b/drivers/gpu/drm/i915/intel_dp.c
@@ -49,6 +49,7 @@
uint8_t link_configuration[DP_LINK_CONFIGURATION_SIZE];
bool has_audio;
int force_audio;
+ uint32_t color_range;
int dpms_mode;
uint8_t link_bw;
uint8_t lane_count;
@@ -741,8 +742,8 @@
struct drm_crtc *crtc = intel_dp->base.base.crtc;
struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
- intel_dp->DP = (DP_VOLTAGE_0_4 |
- DP_PRE_EMPHASIS_0);
+ intel_dp->DP = DP_VOLTAGE_0_4 | DP_PRE_EMPHASIS_0;
+ intel_dp->DP |= intel_dp->color_range;
if (adjusted_mode->flags & DRM_MODE_FLAG_PHSYNC)
intel_dp->DP |= DP_SYNC_HS_HIGH;
@@ -1680,6 +1681,7 @@
struct drm_property *property,
uint64_t val)
{
+ struct drm_i915_private *dev_priv = connector->dev->dev_private;
struct intel_dp *intel_dp = intel_attached_dp(connector);
int ret;
@@ -1708,6 +1710,14 @@
goto done;
}
+ if (property == dev_priv->broadcast_rgb_property) {
+ if (val == !!intel_dp->color_range)
+ return 0;
+
+ intel_dp->color_range = val ? DP_COLOR_RANGE_16_235 : 0;
+ goto done;
+ }
+
return -EINVAL;
done:
@@ -1827,6 +1837,8 @@
intel_dp->force_audio_property->values[1] = 1;
drm_connector_attach_property(connector, intel_dp->force_audio_property, 0);
}
+
+ intel_attach_broadcast_rgb_property(connector);
}
void