drm/i915/display: Enable HDR on gen9 devices with MCA Lspcon

Gen9 hardware supports HDMI2.0 through LSPCON chips.
Extending HDR support for MCA LSPCON based GEN9 devices.

SOC will drive LSPCON as DP and send HDR metadata as standard
DP SDP packets. LSPCON will be set to operate in PCON mode,
will receive the metadata and create Dynamic Range and
Mastering Infoframe (DRM packets) and send it to HDR capable
HDMI sink devices.

v2: Re-used hsw infoframe write implementation for HDR metadata
for LSPCON as per Ville's suggestion.

v3: Addressed Jani Nikula's review comments.

v4: Addressed Ville's review comments, removed redundant wrapper
and checks, passed arguments instead of hardcodings.
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201130204738.2443-3-uma.shankar@intel.com

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

@@ -518,10 +518,10 @@ static u32 vlv_infoframes_enabled(struct intel_encoder *encoder,
 		      VIDEO_DIP_ENABLE_SPD | VIDEO_DIP_ENABLE_GCP);
 }
 
-static void hsw_write_infoframe(struct intel_encoder *encoder,
-				const struct intel_crtc_state *crtc_state,
-				unsigned int type,
-				const void *frame, ssize_t len)
+void hsw_write_infoframe(struct intel_encoder *encoder,
+			 const struct intel_crtc_state *crtc_state,
+			 unsigned int type,
+			 const void *frame, ssize_t len)
 {
 	const u32 *data = frame;
 	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);

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

@@ -445,27 +445,32 @@ void lspcon_write_infoframe(struct intel_encoder *encoder,
 			    unsigned int type,
 			    const void *frame, ssize_t len)
 {
-	bool ret;
+	bool ret = true;
 	struct intel_dp *intel_dp = enc_to_intel_dp(encoder);
 	struct intel_lspcon *lspcon = enc_to_intel_lspcon(encoder);
 
-	/* LSPCON only needs AVI IF */
-	if (type != HDMI_INFOFRAME_TYPE_AVI)
+	switch (type) {
+	case HDMI_INFOFRAME_TYPE_AVI:
+		if (lspcon->vendor == LSPCON_VENDOR_MCA)
+			ret = _lspcon_write_avi_infoframe_mca(&intel_dp->aux,
+							      frame, len);
+		else
+			ret = _lspcon_write_avi_infoframe_parade(&intel_dp->aux,
+								 frame, len);
+		break;
+	case HDMI_PACKET_TYPE_GAMUT_METADATA:
+		drm_dbg_kms(encoder->base.dev, "Update HDR metadata for lspcon\n");
+		/* It uses the legacy hsw implementation for the same */
+		hsw_write_infoframe(encoder, crtc_state, type, frame, len);
+		break;
+	default:
 		return;
-
-	if (lspcon->vendor == LSPCON_VENDOR_MCA)
-		ret = _lspcon_write_avi_infoframe_mca(&intel_dp->aux,
-						      frame, len);
-	else
-		ret = _lspcon_write_avi_infoframe_parade(&intel_dp->aux,
-							 frame, len);
+	}
 
 	if (!ret) {
-		DRM_ERROR("Failed to write AVI infoframes\n");
+		DRM_ERROR("Failed to write infoframes\n");
 		return;
 	}
-
-	DRM_DEBUG_DRIVER("AVI infoframes updated successfully\n");
 }
 
 void lspcon_read_infoframe(struct intel_encoder *encoder,

drivers/gpu/drm/i915/display/intel_lspcon.h

@@ -32,5 +32,9 @@ void lspcon_set_infoframes(struct intel_encoder *encoder,
 			   const struct drm_connector_state *conn_state);
 u32 lspcon_infoframes_enabled(struct intel_encoder *encoder,
 			      const struct intel_crtc_state *pipe_config);
+void hsw_write_infoframe(struct intel_encoder *encoder,
+			 const struct intel_crtc_state *crtc_state,
+			 unsigned int type,
+			 const void *frame, ssize_t len);
 
 #endif /* __INTEL_LSPCON_H__ */