From: Marius Vlad <marius.vlad@collabora.com>

While the two enums have similar values, they're not identical, and
HDMI's enum is defined as per the HDMI standard.

Add a simple conversion function. Unexpected inputs aren't handled in
any clever way, DRM_COLOR_FORMAT_AUTO and any other value that doesn't
cleanly map to HDMI just gets returned as HDMI_COLORSPACE_RGB.

Signed-off-by: Marius Vlad <marius.vlad@collabora.com>
Signed-off-by: Nicolas Frattaroli <nicolas.frattaroli@collabora.com>
---
 include/drm/drm_connector.h | 27 +++++++++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/include/drm/drm_connector.h b/include/drm/drm_connector.h
index 38968a557b82..cf556f0e5731 100644
--- a/include/drm/drm_connector.h
+++ b/include/drm/drm_connector.h
@@ -2567,6 +2567,33 @@ int drm_connector_attach_color_format_property(struct drm_connector *connector);
 
 const char *drm_get_color_format_name(enum drm_color_format color_fmt);
 
+/**
+ * drm_color_format_to_hdmi_colorspace - convert DRM color format to HDMI
+ * @fmt: the &enum drm_color_format to convert
+ *
+ * Convert a given &enum drm_color_format to an equivalent
+ * &enum hdmi_colorspace. For non-representable values and
+ * %DRM_COLOR_FORMAT_AUTO, the value %HDMI_COLORSPACE_RGB is returned.
+ *
+ * Returns: the corresponding &enum hdmi_colorspace value
+ */
+static inline enum hdmi_colorspace __pure
+drm_color_format_to_hdmi_colorspace(enum drm_color_format fmt)
+{
+	switch (fmt) {
+	default:
+	case DRM_COLOR_FORMAT_AUTO:
+	case DRM_COLOR_FORMAT_RGB444:
+		return HDMI_COLORSPACE_RGB;
+	case DRM_COLOR_FORMAT_YCBCR444:
+		return HDMI_COLORSPACE_YUV444;
+	case DRM_COLOR_FORMAT_YCBCR422:
+		return HDMI_COLORSPACE_YUV422;
+	case DRM_COLOR_FORMAT_YCBCR420:
+		return HDMI_COLORSPACE_YUV420;
+	}
+}
+
 /**
  * drm_for_each_connector_iter - connector_list iterator macro
  * @connector: &struct drm_connector pointer used as cursor

-- 
2.52.0