linux-kernel - [PATCH 5.4 099/389] drm/mediatek: Add pull-down MIPI operation in mtk_dsi

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20220823080119.747901417@linuxfoundation.org>
Date:   Tue, 23 Aug 2022 10:22:57 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Jitao Shi <jitao.shi@...iatek.com>,
        Xinlei Lee <xinlei.lee@...iatek.com>,
        Rex-BC Chen <rex-bc.chen@...iatek.com>,
        Chun-Kuang Hu <chunkuang.hu@...nel.org>,
        Sasha Levin <sashal@...nel.org>
Subject: [PATCH 5.4 099/389] drm/mediatek: Add pull-down MIPI operation in mtk_dsi_poweroff function

From: Xinlei Lee <xinlei.lee@...iatek.com>

[ Upstream commit fa5d0a0205c34734c5b8daa77e39ac2817f63a10 ]

In the dsi_enable function, mtk_dsi_rxtx_control is to
pull up the MIPI signal operation. Before dsi_disable,
MIPI should also be pulled down by writing a register
instead of disabling dsi.

If disable dsi without pulling the mipi signal low, the value of
the register will still maintain the setting of the mipi signal being
pulled high.
After resume, even if the mipi signal is not pulled high, it will still
be in the high state.

Fixes: 2e54c14e310f ("drm/mediatek: Add DSI sub driver")

Link: https://patchwork.kernel.org/project/linux-mediatek/patch/1653012007-11854-5-git-send-email-xinlei.lee@mediatek.com/
Signed-off-by: Jitao Shi <jitao.shi@...iatek.com>
Signed-off-by: Xinlei Lee <xinlei.lee@...iatek.com>
Reviewed-by: Rex-BC Chen <rex-bc.chen@...iatek.com>
Signed-off-by: Chun-Kuang Hu <chunkuang.hu@...nel.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 drivers/gpu/drm/mediatek/mtk_dsi.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/gpu/drm/mediatek/mtk_dsi.c b/drivers/gpu/drm/mediatek/mtk_dsi.c
index 224afb666881..e82705a33acf 100644
--- a/drivers/gpu/drm/mediatek/mtk_dsi.c
+++ b/drivers/gpu/drm/mediatek/mtk_dsi.c
@@ -645,6 +645,8 @@ static void mtk_dsi_poweroff(struct mtk_dsi *dsi)
 	mtk_dsi_reset_engine(dsi);
 	mtk_dsi_lane0_ulp_mode_enter(dsi);
 	mtk_dsi_clk_ulp_mode_enter(dsi);
+	/* set the lane number as 0 to pull down mipi */
+	writel(0, dsi->regs + DSI_TXRX_CTRL);
 
 	mtk_dsi_disable(dsi);
 
-- 
2.35.1