Commit ef24fbd8 authored by Liankun Yang's avatar Liankun Yang Committed by Chun-Kuang Hu
Browse files

drm/mediatek: Fix YCbCr422 color format issue for DP 



Setting up misc0 for Pixel Encoding Format.

According to the definition of YCbCr in spec 1.2a Table 2-96,
0x1 << 1 should be written to the register.

Use switch case to distinguish RGB, YCbCr422,
and unsupported color formats.

Fixes: f70ac097 ("drm/mediatek: Add MT8195 Embedded DisplayPort driver")
Signed-off-by: default avatarLiankun Yang <liankun.yang@mediatek.com>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20241025083036.8829-2-liankun.yang@mediatek.com/


Signed-off-by: default avatarChun-Kuang Hu <chunkuang.hu@kernel.org>
parent a10f2606

drivers/gpu/drm/mediatek/mtk_dp.c

+8 −5
Original line number Diff line number Diff line
@@ -543,18 +543,16 @@ static int mtk_dp_set_color_format(struct mtk_dp *mtk_dp, 
				   enum dp_pixelformat color_format)

{

	u32 val;



	/* update MISC0 */

	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3034,

			   color_format << DP_TEST_COLOR_FORMAT_SHIFT,

			   DP_TEST_COLOR_FORMAT_MASK);

	u32 misc0_color;



	switch (color_format) {

	case DP_PIXELFORMAT_YUV422:

		val = PIXEL_ENCODE_FORMAT_DP_ENC0_P0_YCBCR422;

		misc0_color = DP_COLOR_FORMAT_YCbCr422;

		break;

	case DP_PIXELFORMAT_RGB:

		val = PIXEL_ENCODE_FORMAT_DP_ENC0_P0_RGB;

		misc0_color = DP_COLOR_FORMAT_RGB;

		break;

	default:

		drm_warn(mtk_dp->drm_dev, "Unsupported color format: %d\n",
@@ -562,6 +560,11 @@ static int mtk_dp_set_color_format(struct mtk_dp *mtk_dp, 
		return -EINVAL;

	}



	/* update MISC0 */

	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_3034,

			   misc0_color,

			   DP_TEST_COLOR_FORMAT_MASK);



	mtk_dp_update_bits(mtk_dp, MTK_DP_ENC0_P0_303C,

			   val, PIXEL_ENCODE_FORMAT_DP_ENC0_P0_MASK);

	return 0;