drm/i915/hdmi: Extract intel_hdmi_output_format()

Reorganize the HDMI 4:2:0 handling a bit by introducing
intel_hdmi_output_format(). We already have the DP counterpart
and I want to unify the 4:2:0 handling across both a bit.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20211015133921.4609-6-ville.syrjala@linux.intel.comReviewed-by: Jani Nikula <jani.nikula@intel.com>

drivers/gpu/drm/i915/display/intel_hdmi.c

@@ -2157,21 +2157,30 @@ static bool intel_hdmi_has_audio(struct intel_encoder *encoder,
 		return intel_conn_state->force_audio == HDMI_AUDIO_ON;
 }
 
+static enum intel_output_format
+intel_hdmi_output_format(struct intel_connector *connector,
+			 bool ycbcr_420_output)
+{
+	if (connector->base.ycbcr_420_allowed && ycbcr_420_output)
+		return INTEL_OUTPUT_FORMAT_YCBCR420;
+	else
+		return INTEL_OUTPUT_FORMAT_RGB;
+}
+
 static int intel_hdmi_compute_output_format(struct intel_encoder *encoder,
 					    struct intel_crtc_state *crtc_state,
 					    const struct drm_connector_state *conn_state)
 {
-	struct drm_connector *connector = conn_state->connector;
-	struct drm_i915_private *i915 = to_i915(connector->dev);
+	struct intel_connector *connector = to_intel_connector(conn_state->connector);
 	const struct drm_display_mode *adjusted_mode = &crtc_state->hw.adjusted_mode;
+	const struct drm_display_info *info = &connector->base.display_info;
+	struct drm_i915_private *i915 = to_i915(connector->base.dev);
+	bool ycbcr_420_only = drm_mode_is_420_only(info, adjusted_mode);
 	int ret;
-	bool ycbcr_420_only;
 
-	ycbcr_420_only = drm_mode_is_420_only(&connector->display_info, adjusted_mode);
-	if (connector->ycbcr_420_allowed && ycbcr_420_only) {
-		crtc_state->output_format = INTEL_OUTPUT_FORMAT_YCBCR420;
-	} else {
-		if (!connector->ycbcr_420_allowed && ycbcr_420_only)
+	crtc_state->output_format = intel_hdmi_output_format(connector, ycbcr_420_only);
+
+	if (ycbcr_420_only && !intel_hdmi_is_ycbcr420(crtc_state)) {
 		drm_dbg_kms(&i915->drm,
 			    "YCbCr 4:2:0 mode but YCbCr 4:2:0 output not possible. Falling back to RGB.\n");
 		crtc_state->output_format = INTEL_OUTPUT_FORMAT_RGB;
@@ -2180,11 +2189,11 @@ static int intel_hdmi_compute_output_format(struct intel_encoder *encoder,
 	ret = intel_hdmi_compute_clock(encoder, crtc_state);
 	if (ret) {
 		if (intel_hdmi_is_ycbcr420(crtc_state) ||
-		    !connector->ycbcr_420_allowed ||
-		    !drm_mode_is_420_also(&connector->display_info, adjusted_mode))
+		    !connector->base.ycbcr_420_allowed ||
+		    !drm_mode_is_420_also(info, adjusted_mode))
 			return ret;
 
-		crtc_state->output_format = INTEL_OUTPUT_FORMAT_YCBCR420;
+		crtc_state->output_format = intel_hdmi_output_format(connector, true);
 		ret = intel_hdmi_compute_clock(encoder, crtc_state);
 	}