From 03c5b2a5f6c39fe4e090346536cf1c14ee18b61e Mon Sep 17 00:00:00 2001
From: Chris Morgan <macromorgan@hotmail.com>
Date: Fri, 17 Nov 2023 13:44:02 -0600
Subject: [PATCH] drm/panel-elida-kd35t133: hold panel in reset for unprepare
Git-commit: 03c5b2a5f6c39fe4e090346536cf1c14ee18b61e
Patch-mainline: v6.8-rc1
References: git-fixes

For devices like the Anbernic RG351M and RG351P the panel is wired to
an always on regulator. When the device suspends and wakes up, there
are some slight artifacts on the screen that go away over time. If
instead we hold the panel in reset status after it is unprepared,
this does not happen.

Fixes: 5b6603360c12 ("drm/panel: add panel driver for Elida KD35T133 panels")
Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Reviewed-by: Jessica Zhang <quic_jesszhan@quicinc.com>
Link: https://lore.kernel.org/r/20231117194405.1386265-3-macroalpha82@gmail.com
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20231117194405.1386265-3-macroalpha82@gmail.com
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/gpu/drm/panel/panel-elida-kd35t133.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/panel/panel-elida-kd35t133.c b/drivers/gpu/drm/panel/panel-elida-kd35t133.c
index 6cd8536c09ff..f1fc4a26f447 100644
--- a/drivers/gpu/drm/panel/panel-elida-kd35t133.c
+++ b/drivers/gpu/drm/panel/panel-elida-kd35t133.c
@@ -104,6 +104,8 @@ static int kd35t133_unprepare(struct drm_panel *panel)
 		return ret;
 	}
 
+	gpiod_set_value_cansleep(ctx->reset_gpio, 1);
+
 	regulator_disable(ctx->iovcc);
 	regulator_disable(ctx->vdd);
 
-- 
2.35.3