6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Hsiao Chien Sung <shawn.sung@xxxxxxxxxxxx>
[ Upstream commit 231c020141cb150a59f5b28379cad82ff7bad899 ]
9-bit alpha (max=0x100) is designed for special HDR related
calculation, which should be disabled by default.
Change the alpha value from 0x100 to 0xff in 8-bit form.
Fixes: d886c0009bd0 ("drm/mediatek: Add ETHDR support for MT8195")
Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>
Reviewed-by: CK Hu <ck.hu@xxxxxxxxxxxx>
Signed-off-by: Hsiao Chien Sung <shawn.sung@xxxxxxxxxxxx>
Link: https://patchwork.kernel.org/project/dri-devel/patch/20240620-igt-v3-2-a9d62d2e2c7e@xxxxxxxxxxxx/
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/mediatek/mtk_ethdr.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/gpu/drm/mediatek/mtk_ethdr.c b/drivers/gpu/drm/mediatek/mtk_ethdr.c
index db7ac666ec5e1..5b5a0e149e0a3 100644
--- a/drivers/gpu/drm/mediatek/mtk_ethdr.c
+++ b/drivers/gpu/drm/mediatek/mtk_ethdr.c
@@ -50,7 +50,6 @@
#define MIXER_INX_MODE_BYPASS 0
#define MIXER_INX_MODE_EVEN_EXTEND 1
-#define DEFAULT_9BIT_ALPHA 0x100
#define MIXER_ALPHA_AEN BIT(8)
#define MIXER_ALPHA 0xff
#define ETHDR_CLK_NUM 13
@@ -169,7 +168,7 @@ void mtk_ethdr_layer_config(struct device *dev, unsigned int idx,
alpha_con = MIXER_ALPHA_AEN | MIXER_ALPHA;
mtk_mmsys_mixer_in_config(priv->mmsys_dev, idx + 1, alpha_con ? false : true,
- DEFAULT_9BIT_ALPHA,
+ MIXER_ALPHA,
pending->x & 1 ? MIXER_INX_MODE_EVEN_EXTEND :
MIXER_INX_MODE_BYPASS, align_width / 2 - 1, cmdq_pkt);
--
2.43.0
