drm: Add optional COLOR_ENCODING and COLOR_RANGE properties to drm_plane

Add a standard optional properties to support different non RGB color
encodings in DRM planes. COLOR_ENCODING select the supported non RGB
color encoding, for instance ITU-R BT.709 YCbCr. COLOR_RANGE selects
the value ranges within the selected color encoding. The properties
are stored to drm_plane object to allow different set of supported
encoding for different planes on the device.

v2: Add/fix kerneldocs, verify bitmasks (danvet)

Cc: Harry Wentland <harry.wentland@amd.com>
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Daniel Stone <daniel@fooishbar.org>
Cc: Russell King - ARM Linux <linux@armlinux.org.uk>
Cc: Ilia Mirkin <imirkin@alum.mit.edu>
Cc: Hans Verkuil <hverkuil@xs4all.nl>
Cc: Uma Shankar <uma.shankar@intel.com>
Cc: Shashank Sharma <shashank.sharma@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Jyri Sarha <jsarha@ti.com>
[vsyrjala v2: Add/fix kerneldocs, verify bitmasks]
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180219202823.10508-1-ville.syrjala@linux.intel.com
Acked-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/drm_atomic.c

@@ -759,6 +759,10 @@ static int drm_atomic_plane_set_property(struct drm_plane *plane,
 		state->rotation = val;
 	} else if (property == plane->zpos_property) {
 		state->zpos = val;
+	} else if (property == plane->color_encoding_property) {
+		state->color_encoding = val;
+	} else if (property == plane->color_range_property) {
+		state->color_range = val;
 	} else if (plane->funcs->atomic_set_property) {
 		return plane->funcs->atomic_set_property(plane, state,
 				property, val);
@@ -818,6 +822,10 @@ drm_atomic_plane_get_property(struct drm_plane *plane,
 		*val = state->rotation;
 	} else if (property == plane->zpos_property) {
 		*val = state->zpos;
+	} else if (property == plane->color_encoding_property) {
+		*val = state->color_encoding;
+	} else if (property == plane->color_range_property) {
+		*val = state->color_range;
 	} else if (plane->funcs->atomic_get_property) {
 		return plane->funcs->atomic_get_property(plane, state, property, val);
 	} else {

drivers/gpu/drm/drm_color_mgmt.c

@@ -88,6 +88,20 @@
  * drm_mode_crtc_set_gamma_size(). Drivers which support both should use
  * drm_atomic_helper_legacy_gamma_set() to alias the legacy gamma ramp with the
  * "GAMMA_LUT" property above.
+ *
+ * Support for different non RGB color encodings is controlled through
+ * &drm_plane specific COLOR_ENCODING and COLOR_RANGE properties. They
+ * are set up by calling drm_plane_create_color_properties().
+ *
+ * "COLOR_ENCODING"
+ * 	Optional plane enum property to support different non RGB
+ * 	color encodings. The driver can provide a subset of standard
+ * 	enum values supported by the DRM plane.
+ *
+ * "COLOR_RANGE"
+ * 	Optional plane enum property to support different non RGB
+ * 	color parameter ranges. The driver can provide a subset of
+ * 	standard enum values supported by the DRM plane.
  */
 
 /**
@@ -339,3 +353,92 @@ out:
 	drm_modeset_unlock(&crtc->mutex);
 	return ret;
 }
+
+static const char * const color_encoding_name[] = {
+	[DRM_COLOR_YCBCR_BT601] = "ITU-R BT.601 YCbCr",
+	[DRM_COLOR_YCBCR_BT709] = "ITU-R BT.709 YCbCr",
+	[DRM_COLOR_YCBCR_BT2020] = "ITU-R BT.2020 YCbCr",
+};
+
+static const char * const color_range_name[] = {
+	[DRM_COLOR_YCBCR_FULL_RANGE] = "YCbCr full range",
+	[DRM_COLOR_YCBCR_LIMITED_RANGE] = "YCbCr limited range",
+};
+
+/**
+ * drm_plane_create_color_properties - color encoding related plane properties
+ * @plane: plane object
+ * @supported_encodings: bitfield indicating supported color encodings
+ * @supported_ranges: bitfileld indicating supported color ranges
+ * @default_encoding: default color encoding
+ * @default_range: default color range
+ *
+ * Create and attach plane specific COLOR_ENCODING and COLOR_RANGE
+ * properties to @plane. The supported encodings and ranges should
+ * be provided in supported_encodings and supported_ranges bitmasks.
+ * Each bit set in the bitmask indicates that its number as enum
+ * value is supported.
+ */
+int drm_plane_create_color_properties(struct drm_plane *plane,
+				      u32 supported_encodings,
+				      u32 supported_ranges,
+				      enum drm_color_encoding default_encoding,
+				      enum drm_color_range default_range)
+{
+	struct drm_device *dev = plane->dev;
+	struct drm_property *prop;
+	struct drm_prop_enum_list enum_list[max(DRM_COLOR_ENCODING_MAX,
+						DRM_COLOR_RANGE_MAX)];
+	int i, len;
+
+	if (WARN_ON(supported_encodings == 0 ||
+		    (supported_encodings & -BIT(DRM_COLOR_ENCODING_MAX)) != 0 ||
+		    (supported_encodings & BIT(default_encoding)) == 0))
+		return -EINVAL;
+
+	if (WARN_ON(supported_ranges == 0 ||
+		    (supported_ranges & -BIT(DRM_COLOR_RANGE_MAX)) != 0 ||
+		    (supported_ranges & BIT(default_range)) == 0))
+		return -EINVAL;
+
+	len = 0;
+	for (i = 0; i < DRM_COLOR_ENCODING_MAX; i++) {
+		if ((supported_encodings & BIT(i)) == 0)
+			continue;
+
+		enum_list[len].type = i;
+		enum_list[len].name = color_encoding_name[i];
+		len++;
+	}
+
+	prop = drm_property_create_enum(dev, 0, "COLOR_ENCODING",
+					enum_list, len);
+	if (!prop)
+		return -ENOMEM;
+	plane->color_encoding_property = prop;
+	drm_object_attach_property(&plane->base, prop, default_encoding);
+	if (plane->state)
+		plane->state->color_encoding = default_encoding;
+
+	len = 0;
+	for (i = 0; i < DRM_COLOR_RANGE_MAX; i++) {
+		if ((supported_ranges & BIT(i)) == 0)
+			continue;
+
+		enum_list[len].type = i;
+		enum_list[len].name = color_range_name[i];
+		len++;
+	}
+
+	prop = drm_property_create_enum(dev, 0,	"COLOR_RANGE",
+					enum_list, len);
+	if (!prop)
+		return -ENOMEM;
+	plane->color_range_property = prop;
+	drm_object_attach_property(&plane->base, prop, default_range);
+	if (plane->state)
+		plane->state->color_range = default_range;
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_plane_create_color_properties);

include/drm/drm_color_mgmt.h

@@ -26,6 +26,7 @@
 #include <linux/ctype.h>
 
 struct drm_crtc;
+struct drm_plane;
 
 uint32_t drm_color_lut_extract(uint32_t user_input, uint32_t bit_precision);
 
@@ -37,4 +38,22 @@ void drm_crtc_enable_color_mgmt(struct drm_crtc *crtc,
 int drm_mode_crtc_set_gamma_size(struct drm_crtc *crtc,
 				 int gamma_size);
 
+enum drm_color_encoding {
+	DRM_COLOR_YCBCR_BT601,
+	DRM_COLOR_YCBCR_BT709,
+	DRM_COLOR_YCBCR_BT2020,
+	DRM_COLOR_ENCODING_MAX,
+};
+
+enum drm_color_range {
+	DRM_COLOR_YCBCR_LIMITED_RANGE,
+	DRM_COLOR_YCBCR_FULL_RANGE,
+	DRM_COLOR_RANGE_MAX,
+};
+
+int drm_plane_create_color_properties(struct drm_plane *plane,
+				      u32 supported_encodings,
+				      u32 supported_ranges,
+				      enum drm_color_encoding default_encoding,
+				      enum drm_color_range default_range);
 #endif

include/drm/drm_plane.h

@@ -26,6 +26,7 @@
 #include <linux/list.h>
 #include <linux/ctype.h>
 #include <drm/drm_mode_object.h>
+#include <drm/drm_color_mgmt.h>
 
 struct drm_crtc;
 struct drm_printer;
@@ -112,6 +113,20 @@ struct drm_plane_state {
 	unsigned int zpos;
 	unsigned int normalized_zpos;
 
+	/**
+	 * @color_encoding:
+	 *
+	 * Color encoding for non RGB formats
+	 */
+	enum drm_color_encoding color_encoding;
+
+	/**
+	 * @color_range:
+	 *
+	 * Color range for non RGB formats
+	 */
+	enum drm_color_range color_range;
+
 	/* Clipped coordinates */
 	struct drm_rect src, dst;
 
@@ -558,6 +573,23 @@ struct drm_plane {
 
 	struct drm_property *zpos_property;
 	struct drm_property *rotation_property;
+
+	/**
+	 * @color_encoding_property:
+	 *
+	 * Optional "COLOR_ENCODING" enum property for specifying
+	 * color encoding for non RGB formats.
+	 * See drm_plane_create_color_properties().
+	 */
+	struct drm_property *color_encoding_property;
+	/**
+	 * @color_range_property:
+	 *
+	 * Optional "COLOR_RANGE" enum property for specifying
+	 * color range for non RGB formats.
+	 * See drm_plane_create_color_properties().
+	 */
+	struct drm_property *color_range_property;
 };
 
 #define obj_to_plane(x) container_of(x, struct drm_plane, base)