[PATCH v4 6/7] drm/rockchip: dw_hdmi_qp: Set the VOP2 color space from the connector

["Jan Claußen" <jan.claussen10@web.de>]

VOP2 converts RGB to YCbCr using the matrix selected by the CRTC
state's color_space, but the HDMI encoder never sets it, so VOP2
always converts with BT.709. Once the colorspace property can
signal BT.2020 colorimetry to the sink, a YCbCr output would be
encoded with BT.709 and decoded with BT.2020.

Derive color_space from the connector colorspace before the early
return, so that a colorspace change alone is applied.

Signed-off-by: Jan Claußen <jan.claussen10@web.de>
---
 drivers/gpu/drm/rockchip/dw_hdmi_qp-rockchip.c | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/drivers/gpu/drm/rockchip/dw_hdmi_qp-rockchip.c b/drivers/gpu/drm/rockchip/dw_hdmi_qp-rockchip.c
index 9c4cf68d79d5..10c5b6d6406e 100644
--- a/drivers/gpu/drm/rockchip/dw_hdmi_qp-rockchip.c
+++ b/drivers/gpu/drm/rockchip/dw_hdmi_qp-rockchip.c
@@ -17,6 +17,7 @@
 #include <linux/phy/phy.h>
 #include <linux/phy/phy-hdmi.h>
 #include <linux/regmap.h>
+#include <linux/videodev2.h>
 #include <linux/workqueue.h>
 
 #include <drm/bridge/dw_hdmi_qp.h>
@@ -187,6 +188,19 @@ static int dw_hdmi_qp_rockchip_get_vop_format(struct drm_encoder *encoder,
 	return bstate->output_bus_cfg.format;
 }
 
+static u32
+dw_hdmi_qp_rockchip_color_space(const struct drm_connector_state *conn_state)
+{
+	switch (conn_state->colorspace) {
+	case DRM_MODE_COLORIMETRY_BT2020_RGB:
+	case DRM_MODE_COLORIMETRY_BT2020_YCC:
+	case DRM_MODE_COLORIMETRY_BT2020_CYCC:
+		return V4L2_COLORSPACE_BT2020;
+	default:
+		return V4L2_COLORSPACE_DEFAULT;
+	}
+}
+
 static int
 dw_hdmi_qp_rockchip_encoder_atomic_check(struct drm_encoder *encoder,
 					 struct drm_crtc_state *crtc_state,
@@ -202,6 +216,8 @@ dw_hdmi_qp_rockchip_encoder_atomic_check(struct drm_encoder *encoder,
 	if (ingest_fmt < 0)
 		return -EINVAL;
 
+	s->color_space = dw_hdmi_qp_rockchip_color_space(conn_state);
+
 	if (hdmi->tmds_char_rate == conn_state->hdmi.tmds_char_rate &&
 	    s->output_bpc == conn_state->hdmi.output_bpc &&
 	    s->bus_format == ingest_fmt)
-- 
2.56.0