From: Robert Foss <robert.foss@linaro.org>
Date: Tue, 13 Dec 2022 15:03:04 +0000 (+0100)
Subject: drm/bridge: lt9611: Fix PLL being unable to lock
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=2a9df204be0bbb896e087f00b9ee3fc559d5a608;p=linux.git

drm/bridge: lt9611: Fix PLL being unable to lock

This fixes PLL being unable to lock, and is derived from an equivalent
downstream commit.

Available LT9611 documentation does not list this register, neither does
LT9611UXC (which is a different chip).

This commit has been confirmed to fix HDMI output on DragonBoard 845c.

Suggested-by: Amit Pundir <amit.pundir@linaro.org>
Reviewed-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Robert Foss <robert.foss@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20221213150304.4189760-1-robert.foss@linaro.org
---

diff --git a/drivers/gpu/drm/bridge/lontium-lt9611.c b/drivers/gpu/drm/bridge/lontium-lt9611.c
index ffcdc8dba3798..3ce4e495aee50 100644
--- a/drivers/gpu/drm/bridge/lontium-lt9611.c
+++ b/drivers/gpu/drm/bridge/lontium-lt9611.c
@@ -259,6 +259,7 @@ static int lt9611_pll_setup(struct lt9611 *lt9611, const struct drm_display_mode
 		{ 0x8126, 0x55 },
 		{ 0x8127, 0x66 },
 		{ 0x8128, 0x88 },
+		{ 0x812a, 0x20 },
 	};
 
 	regmap_multi_reg_write(lt9611->regmap, reg_cfg, ARRAY_SIZE(reg_cfg));