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From 2ccb21b1e200a3de6d524ad405e4794b1e505171 Mon Sep 17 00:00:00 2001
From: Chen-Yu Tsai <wens@csie.org>
Date: Wed, 9 Mar 2022 00:07:57 +0800
Subject: drm: ssd130x: Fix COM scan direction register mask
Git-commit: efb37e66b7572ce4696aa0ac21675e17d6b9a17d
Patch-mainline: v5.19-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225

The SSD130x's command to toggle COM scan direction uses bit 3 and only
bit 3 to set the direction of the scanout. The driver has an incorrect
GENMASK(3, 2), causing the setting to be set on bit 2, rendering it
ineffective.

Fix the mask to only bit 3, so that the requested setting is applied
correctly.

Fixes: a61732e80867 ("drm: Add driver for Solomon SSD130x OLED displays")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Acked-by: Javier Martinez Canillas <javierm@redhat.com>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220308160758.26060-1-wens@kernel.org
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
 drivers/gpu/drm/solomon/ssd130x.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/solomon/ssd130x.c b/drivers/gpu/drm/solomon/ssd130x.c
index ce4dc20412e0..ccd378135589 100644
--- a/drivers/gpu/drm/solomon/ssd130x.c
+++ b/drivers/gpu/drm/solomon/ssd130x.c
@@ -61,7 +61,7 @@
 #define SSD130X_SET_COM_PINS_CONFIG		0xda
 #define SSD130X_SET_VCOMH			0xdb
 
-#define SSD130X_SET_COM_SCAN_DIR_MASK		GENMASK(3, 2)
+#define SSD130X_SET_COM_SCAN_DIR_MASK		GENMASK(3, 3)
 #define SSD130X_SET_COM_SCAN_DIR_SET(val)	FIELD_PREP(SSD130X_SET_COM_SCAN_DIR_MASK, (val))
 #define SSD130X_SET_CLOCK_DIV_MASK		GENMASK(3, 0)
 #define SSD130X_SET_CLOCK_DIV_SET(val)		FIELD_PREP(SSD130X_SET_CLOCK_DIV_MASK, (val))
-- 
2.38.1