[PATCH v3] drm: bridge: dw-hdmi: add HDMI vendor specific infoframe config

[Nickey Yang]

Vendor specific infoframe is mandatory for 4K2K resolution.
Without this, the HDMI protocol compliance fails.

Signed-off-by: Nickey Yang <nickey.yang@xxxxxxxxxxxxxx>
Reviewed-by: Jose Abreu <joabreu@xxxxxxxxxxxx>
---
 drivers/gpu/drm/bridge/dw-hdmi.c | 53 ++++++++++++++++++++++++++++++++++++++++
 drivers/gpu/drm/bridge/dw-hdmi.h |  4 +++
 2 files changed, 57 insertions(+)

diff --git a/drivers/gpu/drm/bridge/dw-hdmi.c b/drivers/gpu/drm/bridge/dw-hdmi.c
index 9a9ec27..6b29d1a 100644
--- a/drivers/gpu/drm/bridge/dw-hdmi.c
+++ b/drivers/gpu/drm/bridge/dw-hdmi.c
@@ -1195,6 +1195,58 @@ static void hdmi_config_AVI(struct dw_hdmi *hdmi, struct drm_display_mode *mode)
 	hdmi_writeb(hdmi, (frame.right_bar >> 8) & 0xff, HDMI_FC_AVISRB1);
 }
 
+static void hdmi_config_vendor_specific_infoframe(struct dw_hdmi *hdmi,
+						 struct drm_display_mode *mode)
+{
+	struct hdmi_vendor_infoframe frame;
+	u8 buffer[10];
+	ssize_t err;
+
+	err = drm_hdmi_vendor_infoframe_from_display_mode(&frame, mode);
+	if (err < 0)
+		/*
+		 * Going into that statement does not means vendor infoframe
+		 * fails. It just informed us that vendor infoframe is not
+		 * needed for the selected mode. Only 4k or stereoscopic 3D
+		 * mode requires vendor infoframe. So just simply return.
+		 */
+		return;
+
+	err = hdmi_vendor_infoframe_pack(&frame, buffer, sizeof(buffer));
+	if (err < 0) {
+		dev_err(hdmi->dev, "Failed to pack vendor infoframe: %zd\n",
+			err);
+		return;
+	}
+	hdmi_mask_writeb(hdmi, 0, HDMI_FC_DATAUTO0, HDMI_FC_DATAUTO0_VSD_OFFSET,
+			HDMI_FC_DATAUTO0_VSD_MASK);
+
+	/* Set the length of HDMI vendor specific InfoFrame payload */
+	hdmi_writeb(hdmi, buffer[2], HDMI_FC_VSDSIZE);
+
+	/* Set 24bit IEEE Registration Identifier */
+	hdmi_writeb(hdmi, buffer[4], HDMI_FC_VSDIEEEID0);
+	hdmi_writeb(hdmi, buffer[5], HDMI_FC_VSDIEEEID1);
+	hdmi_writeb(hdmi, buffer[6], HDMI_FC_VSDIEEEID2);
+
+	/* Set HDMI_Video_Format and HDMI_VIC/3D_Structure */
+	hdmi_writeb(hdmi, buffer[7], HDMI_FC_VSDPAYLOAD0);
+	hdmi_writeb(hdmi, buffer[8], HDMI_FC_VSDPAYLOAD1);
+
+	if (frame.s3d_struct >= HDMI_3D_STRUCTURE_SIDE_BY_SIDE_HALF)
+		hdmi_writeb(hdmi, buffer[9], HDMI_FC_VSDPAYLOAD2);
+
+	/* Packet frame interpolation */
+	hdmi_writeb(hdmi, 1, HDMI_FC_DATAUTO1);
+
+	/* Auto packets per frame and line spacing */
+	hdmi_writeb(hdmi, 0x11, HDMI_FC_DATAUTO2);
+
+	/* Configures the Frame Composer On RDRB mode */
+	hdmi_mask_writeb(hdmi, 1, HDMI_FC_DATAUTO0, HDMI_FC_DATAUTO0_VSD_OFFSET,
+			HDMI_FC_DATAUTO0_VSD_MASK);
+}
+
 static void hdmi_av_composer(struct dw_hdmi *hdmi,
 			     const struct drm_display_mode *mode)
 {
@@ -1446,6 +1498,7 @@ static int dw_hdmi_setup(struct dw_hdmi *hdmi, struct drm_display_mode *mode)
 
 		/* HDMI Initialization Step F - Configure AVI InfoFrame */
 		hdmi_config_AVI(hdmi, mode);
+		hdmi_config_vendor_specific_infoframe(hdmi, mode);
 	} else {
 		dev_dbg(hdmi->dev, "%s DVI mode\n", __func__);
 	}
diff --git a/drivers/gpu/drm/bridge/dw-hdmi.h b/drivers/gpu/drm/bridge/dw-hdmi.h
index 325b0b8..c59f87e 100644
--- a/drivers/gpu/drm/bridge/dw-hdmi.h
+++ b/drivers/gpu/drm/bridge/dw-hdmi.h
@@ -854,6 +854,10 @@ enum {
 	HDMI_FC_DBGFORCE_FORCEAUDIO = 0x10,
 	HDMI_FC_DBGFORCE_FORCEVIDEO = 0x1,
 
+/* FC_DATAUTO0 field values */
+	HDMI_FC_DATAUTO0_VSD_MASK = 0x08,
+	HDMI_FC_DATAUTO0_VSD_OFFSET = 3,
+
 /* PHY_CONF0 field values */
 	HDMI_PHY_CONF0_PDZ_MASK = 0x80,
 	HDMI_PHY_CONF0_PDZ_OFFSET = 7,
-- 
1.9.1