[PATCH 04/11] drm/rockchip: inno_hdmi: Correctly setup HDMI quantization range

[Alex Bee]

The display controller will always give full range RGB regardless of the
mode set, but HDMI requires certain modes to be transmitted in limited
range RGB. This is especially required for HDMI sinks which do not support
non-standard quantization ranges.

This enables color space conversion for those modes and sets the
quantization range accordingly in the AVI infoframe.

Fixes: 412d4ae6b7a5 ("drm/rockchip: hdmi: add Innosilicon HDMI support")
Signed-off-by: Alex Bee <knaerzche at gmail.com>
---
 drivers/gpu/drm/rockchip/inno_hdmi.c | 40 ++++++++++++++++++++++------
 1 file changed, 32 insertions(+), 8 deletions(-)

diff --git a/drivers/gpu/drm/rockchip/inno_hdmi.c b/drivers/gpu/drm/rockchip/inno_hdmi.c
index 345253e033c5..32626a75723c 100644
--- a/drivers/gpu/drm/rockchip/inno_hdmi.c
+++ b/drivers/gpu/drm/rockchip/inno_hdmi.c
@@ -33,6 +33,7 @@ struct hdmi_data_info {
 	unsigned int enc_in_format;
 	unsigned int enc_out_format;
 	unsigned int colorimetry;
+	bool rgb_limited_range;
 };
 
 struct inno_hdmi_i2c {
@@ -308,6 +309,18 @@ static int inno_hdmi_config_video_avi(struct inno_hdmi *hdmi,
 	else
 		frame.avi.colorspace = HDMI_COLORSPACE_RGB;
 
+	if (hdmi->hdmi_data.enc_out_format == HDMI_COLORSPACE_RGB) {
+		drm_hdmi_avi_infoframe_quant_range(&frame.avi,
+						   &hdmi->connector, mode,
+						   hdmi->hdmi_data.rgb_limited_range ?
+						   HDMI_QUANTIZATION_RANGE_LIMITED :
+						   HDMI_QUANTIZATION_RANGE_FULL);
+	} else {
+		frame.avi.quantization_range = HDMI_QUANTIZATION_RANGE_DEFAULT;
+		frame.avi.ycc_quantization_range =
+			HDMI_YCC_QUANTIZATION_RANGE_LIMITED;
+	}
+
 	return inno_hdmi_upload_frame(hdmi, rc, &frame, INFOFRAME_AVI, 0, 0, 0);
 }
 
@@ -334,14 +347,22 @@ static int inno_hdmi_config_video_csc(struct inno_hdmi *hdmi)
 	if (data->enc_in_format == data->enc_out_format) {
 		if ((data->enc_in_format == HDMI_COLORSPACE_RGB) ||
 		    (data->enc_in_format >= HDMI_COLORSPACE_YUV444)) {
-			value = v_SOF_DISABLE | v_COLOR_DEPTH_NOT_INDICATED(1);
-			hdmi_writeb(hdmi, HDMI_VIDEO_CONTRL3, value);
-
-			hdmi_modb(hdmi, HDMI_VIDEO_CONTRL,
-				  m_VIDEO_AUTO_CSC | m_VIDEO_C0_C2_SWAP,
-				  v_VIDEO_AUTO_CSC(AUTO_CSC_DISABLE) |
-				  v_VIDEO_C0_C2_SWAP(C0_C2_CHANGE_DISABLE));
-			return 0;
+			if (data->enc_in_format == HDMI_COLORSPACE_RGB &&
+			    data->enc_out_format == HDMI_COLORSPACE_RGB &&
+			    hdmi->hdmi_data.rgb_limited_range) {
+				csc_mode = CSC_RGB_0_255_TO_RGB_16_235_8BIT;
+				auto_csc = AUTO_CSC_DISABLE;
+				c0_c2_change = C0_C2_CHANGE_DISABLE;
+				csc_enable = v_CSC_ENABLE;
+			} else {
+				value = v_SOF_DISABLE | v_COLOR_DEPTH_NOT_INDICATED(1);
+				hdmi_writeb(hdmi, HDMI_VIDEO_CONTRL3, value);
+				hdmi_modb(hdmi, HDMI_VIDEO_CONTRL,
+					  m_VIDEO_AUTO_CSC | m_VIDEO_C0_C2_SWAP,
+					  v_VIDEO_AUTO_CSC(AUTO_CSC_DISABLE) |
+					  v_VIDEO_C0_C2_SWAP(C0_C2_CHANGE_DISABLE));
+				return 0;
+			}
 		}
 	}
 
@@ -458,6 +479,9 @@ static int inno_hdmi_setup(struct inno_hdmi *hdmi,
 	else
 		hdmi->hdmi_data.colorimetry = HDMI_COLORIMETRY_ITU_709;
 
+	hdmi->hdmi_data.rgb_limited_range =
+		drm_default_rgb_quant_range(mode) == HDMI_QUANTIZATION_RANGE_LIMITED;
+
 	/* Mute video and audio output */
 	hdmi_modb(hdmi, HDMI_AV_MUTE, m_AUDIO_MUTE | m_VIDEO_BLACK,
 		  v_AUDIO_MUTE(1) | v_VIDEO_MUTE(1));
-- 
2.43.0