[PATCH 2/5] drm: Add "RGB quantization range" connector property

Yussuf Khalil
2020-04-13T21:51:54Z

Add a new "RGB quantization range" property with three possible values:
Automatic, Limited, and Full. User-space may use this property to override
the automatic selection of the RGB range as specified by CTA-861. Drivers
should attach this property to all CTA-861 sinks.

Signed-off-by: Yussuf Khalil <dev@pp3345.net>
---
drivers/gpu/drm/drm_atomic_uapi.c | 4 ++++
drivers/gpu/drm/drm_connector.c | 35 +++++++++++++++++++++++++++++++
include/drm/drm_connector.h | 23 ++++++++++++++++++++
include/drm/drm_mode_config.h | 7 +++++++
4 files changed, 69 insertions(+)

diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
index a1e5e262bae2..f12b3a40c6cf 100644
--- a/drivers/gpu/drm/drm_atomic_uapi.c
+++ b/drivers/gpu/drm/drm_atomic_uapi.c
@@ -766,6 +766,8 @@ static int drm_atomic_connector_set_property(struct drm_connector *connector,
fence_ptr);
} else if (property == connector->max_bpc_property) {
state->max_requested_bpc = val;
+ } else if (property == config->rgb_quantization_range_property) {
+ state->rgb_quantization_range = val;
} else if (connector->funcs->atomic_set_property) {
return connector->funcs->atomic_set_property(connector,
state, property, val);
@@ -842,6 +844,8 @@ drm_atomic_connector_get_property(struct drm_connector *connector,
*val = 0;
} else if (property == connector->max_bpc_property) {
*val = state->max_requested_bpc;
+ } else if (property == config->rgb_quantization_range_property) {
+ *val = state->rgb_quantization_range;
} else if (connector->funcs->atomic_get_property) {
return connector->funcs->atomic_get_property(connector,
state, property, val);
diff --git a/drivers/gpu/drm/drm_connector.c b/drivers/gpu/drm/drm_connector.c
index 644f0ad10671..e60d3b6e5e56 100644
--- a/drivers/gpu/drm/drm_connector.c
+++ b/drivers/gpu/drm/drm_connector.c
@@ -929,6 +929,12 @@ static const struct drm_prop_enum_list dp_colorspaces[] = {
{ DRM_MODE_COLORIMETRY_BT2020_YCC, "BT2020_YCC" },
};

+static const struct drm_prop_enum_list rgb_quantization_range_options[] = {
+ { DRM_MODE_RGB_QUANTIZATION_RANGE_AUTOMATIC, "Automatic" },
+ { DRM_MODE_RGB_QUANTIZATION_RANGE_LIMITED, "Limited" },
+ { DRM_MODE_RGB_QUANTIZATION_RANGE_FULL, "Full" },
+};
+
/**
* DOC: standard connector properties
*
@@ -1804,6 +1810,35 @@ int drm_mode_create_dp_colorspace_property(struct drm_connector *connector)
}
EXPORT_SYMBOL(drm_mode_create_dp_colorspace_property);

+/**
+ * drm_mode_create_rgb_quantization_range_property - create RGB quantization
+ * range property
+ * @dev: device to create the RGB quantization range property on.
+ *
+ * Called by a driver the first time it's needed, must be attached to connectors
+ * of CEA-861-compliant sinks.
+ *
+ * Returns:
+ * Zero on success, negative errno on failure.
+ */
+int drm_mode_create_rgb_quantization_range_property(struct drm_device *dev)
+{
+ if (dev->mode_config.rgb_quantization_range_property)
+ return 0;
+
+ dev->mode_config.rgb_quantization_range_property =
+ drm_property_create_enum(dev, DRM_MODE_PROP_ENUM,
+ "RGB quantization range",
+ rgb_quantization_range_options,
+ ARRAY_SIZE(rgb_quantization_range_options));
+
+ if (!dev->mode_config.rgb_quantization_range_property)
+ return -ENOMEM;
+
+ return 0;
+}
+EXPORT_SYMBOL(drm_mode_create_rgb_quantization_range_property);
+
/**
* drm_mode_create_content_type_property - create content type property
* @dev: DRM device
diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 19ae6bb5c85b..f605e0fbcc0e 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -303,6 +303,22 @@ struct drm_monitor_range_info {
#define DRM_MODE_COLORIMETRY_RGB_WIDE_FLOAT 14
#define DRM_MODE_COLORIMETRY_BT601_YCC 15

+/**
+ * enum drm_rgb_quantization_range - rgb_quantization_range property value
+ *
+ * This enum lists the possible options for the rgb_quantization_range property.
+ *
+ * @DRM_MODE_RGB_QUANTIZATION_RANGE_AUTOMATIC: Let the driver select the
+ * appropriate quantization range.
+ * @DRM_MODE_RGB_QUANTIZATION_RANGE_LIMITED: Force limited range RGB.
+ * @DRM_MODE_RGB_QUANTIZATION_RANGE_FULL: Force full range RGB.
+ */
+enum drm_rgb_quantization_range {
+ DRM_MODE_RGB_QUANTIZATION_RANGE_AUTOMATIC = 0,
+ DRM_MODE_RGB_QUANTIZATION_RANGE_LIMITED = 1,
+ DRM_MODE_RGB_QUANTIZATION_RANGE_FULL = 2,
+};
+
/**
* enum drm_bus_flags - bus_flags info for &drm_display_info
*
@@ -661,6 +677,12 @@ struct drm_connector_state {
*/
u32 colorspace;

+ /**
+ * @rgb_quantization_range: Connector property to control the selected
+ * RGB quantization range for CEA-861 outputs.
+ */
+ u32 rgb_quantization_range;
+
/**
* @writeback_job: Writeback job for writeback connectors
*
@@ -1575,6 +1597,7 @@ int drm_mode_create_aspect_ratio_property(struct drm_device *dev);
int drm_mode_create_hdmi_colorspace_property(struct drm_connector *connector);
int drm_mode_create_dp_colorspace_property(struct drm_connector *connector);
int drm_mode_create_content_type_property(struct drm_device *dev);
+int drm_mode_create_rgb_quantization_range_property(struct drm_device *dev);
void drm_hdmi_avi_infoframe_content_type(struct hdmi_avi_infoframe *frame,
const struct drm_connector_state *conn_state);

diff --git a/include/drm/drm_mode_config.h b/include/drm/drm_mode_config.h
index 3bcbe30339f0..745587f6b83c 100644
--- a/include/drm/drm_mode_config.h
+++ b/include/drm/drm_mode_config.h
@@ -855,6 +855,13 @@ struct drm_mode_config {
*/
struct drm_property *hdcp_content_type_property;

+ /**
+ * @rgb_quantization_range_property: Connector property to allow
+ * user-space to override the RGB quantization range for CEA-861
+ * outputs.
+ */
+ struct drm_property *rgb_quantization_range_property;
+
/* dumb ioctl parameters */
uint32_t preferred_depth, prefer_shadow;

--
2.26.0