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_sdvo.c b/drivers/gpu/drm/i915/intel_sdvo.c
index 19c817a..9698e91 100644
--- a/drivers/gpu/drm/i915/intel_sdvo.c
+++ b/drivers/gpu/drm/i915/intel_sdvo.c
@@ -93,6 +93,12 @@
uint16_t attached_output;
/**
+ * This is used to select the color range of RBG outputs in HDMI mode.
+ * It is only valid when using TMDS encoding and 8 bit per color mode.
+ */
+ uint32_t color_range;
+
+ /**
* This is set if we're going to treat the device as TV-out.
*
* While we have these nice friendly flags for output types that ought
@@ -1056,6 +1062,8 @@
/* Set the SDVO control regs. */
if (INTEL_INFO(dev)->gen >= 4) {
sdvox = 0;
+ if (intel_sdvo->is_hdmi)
+ sdvox |= intel_sdvo->color_range;
if (INTEL_INFO(dev)->gen < 5)
sdvox |= SDVO_BORDER_ENABLE;
if (adjusted_mode->flags & DRM_MODE_FLAG_PVSYNC)
@@ -1695,6 +1703,7 @@
{
struct intel_sdvo *intel_sdvo = intel_attached_sdvo(connector);
struct intel_sdvo_connector *intel_sdvo_connector = to_intel_sdvo_connector(connector);
+ struct drm_i915_private *dev_priv = connector->dev->dev_private;
uint16_t temp_value;
uint8_t cmd;
int ret;
@@ -1724,6 +1733,14 @@
goto done;
}
+ if (property == dev_priv->broadcast_rgb_property) {
+ if (val == !!intel_sdvo->color_range)
+ return 0;
+
+ intel_sdvo->color_range = val ? SDVO_COLOR_RANGE_16_235 : 0;
+ goto done;
+ }
+
#define CHECK_PROPERTY(name, NAME) \
if (intel_sdvo_connector->name == property) { \
if (intel_sdvo_connector->cur_##name == temp_value) return 0; \
@@ -2028,6 +2045,9 @@
drm_connector_attach_property(&connector->base.base,
connector->force_audio_property, 0);
}
+
+ if (INTEL_INFO(dev)->gen >= 4 && IS_MOBILE(dev))
+ intel_attach_broadcast_rgb_property(&connector->base.base);
}
static bool