linux-kernel - [PATCH v7 03/12] drm/bridge: cdns-dsi: Fix phy de-init and flag it so

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: <20250114055626.18816-4-aradhya.bhatia@linux.dev>
Date: Tue, 14 Jan 2025 11:26:17 +0530
From: Aradhya Bhatia <aradhya.bhatia@...ux.dev>
To: Tomi Valkeinen <tomi.valkeinen@...asonboard.com>,
	Dmitry Baryshkov <dmitry.baryshkov@...aro.org>,
	Laurent Pinchart <laurent.pinchart@...asonboard.com>,
	Andrzej Hajda <andrzej.hajda@...el.com>,
	Neil Armstrong <neil.armstrong@...aro.org>,
	Robert Foss <rfoss@...nel.org>,
	Jonas Karlman <jonas@...boo.se>,
	Jernej Skrabec <jernej.skrabec@...il.com>,
	Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
	Maxime Ripard <mripard@...nel.org>,
	Thomas Zimmermann <tzimmermann@...e.de>,
	David Airlie <airlied@...il.com>,
	Simona Vetter <simona@...ll.ch>
Cc: Nishanth Menon <nm@...com>,
	Vignesh Raghavendra <vigneshr@...com>,
	Devarsh Thakkar <devarsht@...com>,
	Praneeth Bajjuri <praneeth@...com>,
	Udit Kumar <u-kumar1@...com>,
	Jayesh Choudhary <j-choudhary@...com>,
	DRI Development List <dri-devel@...ts.freedesktop.org>,
	Linux Kernel List <linux-kernel@...r.kernel.org>,
	Aradhya Bhatia <aradhya.bhatia@...ux.dev>
Subject: [PATCH v7 03/12] drm/bridge: cdns-dsi: Fix phy de-init and flag it so

From: Aradhya Bhatia <a-bhatia1@...com>

The driver code doesn't have a Phy de-initialization path as yet, and so
it does not clear the phy_initialized flag while suspending. This is a
problem because after resume the driver looks at this flag to determine
if a Phy re-initialization is required or not. It is in fact required
because the hardware is resuming from a suspend, but the driver does not
carry out any re-initialization causing the D-Phy to not work at all.

Call the counterparts of phy_init() and phy_power_on(), that are
phy_exit() and phy_power_off(), from _bridge_disable(), and clear the
flags so that the Phy can be initialized again when required.

Fixes: fced5a364dee ("drm/bridge: cdns: Convert to phy framework")
Signed-off-by: Aradhya Bhatia <a-bhatia1@...com>
Signed-off-by: Aradhya Bhatia <aradhya.bhatia@...ux.dev>
---
 drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c
index 056583e81155..039c5eb7fb66 100644
--- a/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c
+++ b/drivers/gpu/drm/bridge/cadence/cdns-dsi-core.c
@@ -672,6 +672,11 @@ static void cdns_dsi_bridge_disable(struct drm_bridge *bridge)
 	if (dsi->platform_ops && dsi->platform_ops->disable)
 		dsi->platform_ops->disable(dsi);
 
+	dsi->phy_initialized = false;
+	dsi->link_initialized = false;
+	phy_power_off(dsi->dphy);
+	phy_exit(dsi->dphy);
+
 	pm_runtime_put(dsi->base.dev);
 }
 
@@ -1130,7 +1135,6 @@ static int __maybe_unused cdns_dsi_suspend(struct device *dev)
 	clk_disable_unprepare(dsi->dsi_sys_clk);
 	clk_disable_unprepare(dsi->dsi_p_clk);
 	reset_control_assert(dsi->dsi_p_rst);
-	dsi->link_initialized = false;
 	return 0;
 }
 
-- 
2.34.1