Patch "drm/bridge: lt8912b: add vsync hsync" has been added to the 5.15-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    drm/bridge: lt8912b: add vsync hsync

to the 5.15-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-bridge-lt8912b-add-vsync-hsync.patch
and it can be found in the queue-5.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 96f8f0d53999bfcd26a050e87ca5571df29e6dda
Author: Philippe Schenker <philippe.schenker@xxxxxxxxxxx>
Date:   Thu Sep 22 14:43:03 2022 +0200

    drm/bridge: lt8912b: add vsync hsync
    
    [ Upstream commit da73a94fa282f78d485bd0aab36c8ac15b6f792c ]
    
    Currently the bridge driver does not take care whether or not the display
    needs positive/negative vertical/horizontal syncs. Pass these two flags
    to the bridge from the EDID that was read out from the display.
    
    Fixes: 30e2ae943c26 ("drm/bridge: Introduce LT8912B DSI to HDMI bridge")
    Signed-off-by: Philippe Schenker <philippe.schenker@xxxxxxxxxxx>
    Acked-by: Adrien Grassein <adrien.grassein@xxxxxxxxx>
    Signed-off-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
    Link: https://patchwork.freedesktop.org/patch/msgid/20220922124306.34729-2-dev@xxxxxxxxxxxx
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/drivers/gpu/drm/bridge/lontium-lt8912b.c b/drivers/gpu/drm/bridge/lontium-lt8912b.c
index 1b0c7eaf6c84..0fae72d45040 100644
--- a/drivers/gpu/drm/bridge/lontium-lt8912b.c
+++ b/drivers/gpu/drm/bridge/lontium-lt8912b.c
@@ -266,7 +266,7 @@ static int lt8912_video_setup(struct lt8912 *lt)
 	u32 hactive, h_total, hpw, hfp, hbp;
 	u32 vactive, v_total, vpw, vfp, vbp;
 	u8 settle = 0x08;
-	int ret;
+	int ret, hsync_activehigh, vsync_activehigh;
 
 	if (!lt)
 		return -EINVAL;
@@ -276,12 +276,14 @@ static int lt8912_video_setup(struct lt8912 *lt)
 	hpw = lt->mode.hsync_len;
 	hbp = lt->mode.hback_porch;
 	h_total = hactive + hfp + hpw + hbp;
+	hsync_activehigh = lt->mode.flags & DISPLAY_FLAGS_HSYNC_HIGH;
 
 	vactive = lt->mode.vactive;
 	vfp = lt->mode.vfront_porch;
 	vpw = lt->mode.vsync_len;
 	vbp = lt->mode.vback_porch;
 	v_total = vactive + vfp + vpw + vbp;
+	vsync_activehigh = lt->mode.flags & DISPLAY_FLAGS_VSYNC_HIGH;
 
 	if (vactive <= 600)
 		settle = 0x04;
@@ -315,6 +317,11 @@ static int lt8912_video_setup(struct lt8912 *lt)
 	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3e, hfp & 0xff);
 	ret |= regmap_write(lt->regmap[I2C_CEC_DSI], 0x3f, hfp >> 8);
 
+	ret |= regmap_update_bits(lt->regmap[I2C_MAIN], 0xab, BIT(0),
+				  vsync_activehigh ? BIT(0) : 0);
+	ret |= regmap_update_bits(lt->regmap[I2C_MAIN], 0xab, BIT(1),
+				  hsync_activehigh ? BIT(1) : 0);
+
 	return ret;
 }