linux-stable.git/drivers/gpu/drm/bridge, branch linux-6.16.y

drm: bridge: cdns-mhdp8546: Fix missing mutex unlock on error path

2025-09-25T09:16:52+00:00

[ Upstream commit 288dac9fb6084330d968459c750c838fd06e10e6 ]

Add missing mutex unlock before returning from the error path in
cdns_mhdp_atomic_enable().

Fixes: 935a92a1c400 ("drm: bridge: cdns-mhdp8546: Fix possible null pointer dereference")
Reported-by: Hulk Robot 
Signed-off-by: Qi Xi 
Reviewed-by: Luca Ceresoli 
Reviewed-by: Dmitry Baryshkov 
Link: https://lore.kernel.org/r/20250904034447.665427-1-xiqi2@huawei.com
Signed-off-by: Luca Ceresoli 
Signed-off-by: Sasha Levin

drm: bridge: anx7625: Fix NULL pointer dereference with early IRQ

2025-09-25T09:16:51+00:00

[ Upstream commit a10f910c77f280327b481e77eab909934ec508f0 ]

If the interrupt occurs before resource initialization is complete, the
interrupt handler/worker may access uninitialized data such as the I2C
tcpc_client device, potentially leading to NULL pointer dereference.

Signed-off-by: Loic Poulain 
Fixes: 8bdfc5dae4e3 ("drm/bridge: anx7625: Add anx7625 MIPI DSI/DPI to DP")
Reviewed-by: Dmitry Baryshkov 
Link: https://lore.kernel.org/r/20250709085438.56188-1-loic.poulain@oss.qualcomm.com
Signed-off-by: Dmitry Baryshkov 
Signed-off-by: Sasha Levin

drm/bridge: ti-sn65dsi86: fix REFCLK setting

2025-09-09T17:02:38+00:00

[ Upstream commit bdd5a14e660062114bdebaef9ad52adf04970a89 ]

The bridge has three bootstrap pins which are sampled to determine the
frequency of the external reference clock. The driver will also
(over)write that setting. But it seems this is racy after the bridge is
enabled. It was observed that although the driver write the correct
value (by sniffing on the I2C bus), the register has the wrong value.
The datasheet states that the GPIO lines have to be stable for at least
5us after asserting the EN signal. Thus, there seems to be some logic
which samples the GPIO lines and this logic appears to overwrite the
register value which was set by the driver. Waiting 20us after
asserting the EN line resolves this issue.

Fixes: a095f15c00e2 ("drm/bridge: add support for sn65dsi86 bridge driver")
Signed-off-by: Michael Walle 
Reviewed-by: Douglas Anderson 
Signed-off-by: Douglas Anderson 
Link: https://lore.kernel.org/r/20250821122341.1257286-1-mwalle@kernel.org
Signed-off-by: Sasha Levin

Merge tag 'drm-misc-fixes-2025-07-23' of https://gitlab.freedesktop.org/drm/misc/kernel into drm-fixes

2025-07-23T20:49:38+00:00

drm-misc-fixes for v6.16-rc8/final?:
- Revert all uses of drm_gem_object->dmabuf to
  drm_gem_object->import_attach->dmabuf.
- Fix amdgpu returning BIOS cluttered VRAM after resume.
- Scheduler hang fix.
- Revert nouveau ioctl fix as it caused regressions.
- Fix null pointer deref in nouveau.
- Fix unnecessary semicolon in ti_sn_bridge_probe.

Signed-off-by: Dave Airlie 
From: Maarten Lankhorst 
Link: https://lore.kernel.org/r/72235afd-c849-49fe-9cc1-2b1781abdf08@linux.intel.com

drm/bridge: ti-sn65dsi86: Remove extra semicolon in ti_sn_bridge_probe()

2025-07-22T14:46:34+00:00

As reported by the kernel test robot, a recent patch introduced an
unnecessary semicolon. Remove it.

Fixes: 55e8ff842051 ("drm/bridge: ti-sn65dsi86: Add HPD for DisplayPort connector type")
Reported-by: kernel test robot 
Closes: https://lore.kernel.org/oe-kbuild-all/202506301704.0SBj6ply-lkp@intel.com/
Reviewed-by: Devarsh Thakkar 
Signed-off-by: Douglas Anderson 
Link: https://lore.kernel.org/r/20250714130631.1.I1cfae3222e344a3b3c770d079ee6b6f7f3b5d636@changeid

Merge tag 'samsung-dsim-fixes-for-v6.16-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/daeinki/drm-exynos into drm-fixes

2025-07-03T23:40:20+00:00

- Fixed raw pointer leakage and unsafe behavior in printk()
  . Switch from %pK to %p for pointer formatting, as %p is now safer
    and prevents issues like raw pointer leakage and acquiring sleeping
    locks in atomic contexts.

Signed-off-by: Dave Airlie 

From: Inki Dae 
Link: https://lore.kernel.org/r/20250629091742.29956-1-inki.dae@samsung.com

drm/bridge: aux-hpd-bridge: fix assignment of the of_node

2025-06-30T15:43:17+00:00

Perform fix similar to the one in the commit 85e444a68126 ("drm/bridge:
Fix assignment of the of_node of the parent to aux bridge").

The assignment of the of_node to the aux HPD bridge needs to mark the
of_node as reused, otherwise driver core will attempt to bind resources
like pinctrl, which is going to fail as corresponding pins are already
marked as used by the parent device.
Fix that by using the device_set_of_node_from_dev() helper instead of
assigning it directly.

Fixes: e560518a6c2e ("drm/bridge: implement generic DP HPD bridge")
Signed-off-by: Dmitry Baryshkov 
Reviewed-by: Neil Armstrong 
Signed-off-by: Neil Armstrong 
Link: https://lore.kernel.org/r/20250608-fix-aud-hpd-bridge-v1-1-4641a6f8e381@oss.qualcomm.com

drm/bridge: panel: move prepare_prev_first handling to drm_panel_bridge_add_typed

2025-06-30T15:42:32+00:00

The commit 5ea6b1702781 ("drm/panel: Add prepare_prev_first flag to
drm_panel") and commit 0974687a19c3 ("drm/bridge: panel: Set
pre_enable_prev_first from drmm_panel_bridge_add") added handling of
panel's prepare_prev_first to devm_panel_bridge_add() and
drmm_panel_bridge_add(). However if the driver calls
drm_panel_bridge_add_typed() directly, then the flag won't be handled
and thus the drm_bridge.pre_enable_prev_first will not be set.

Move prepare_prev_first handling to the drm_panel_bridge_add_typed() so
that there is no way to miss the flag.

Fixes: 5ea6b1702781 ("drm/panel: Add prepare_prev_first flag to drm_panel")
Fixes: 0974687a19c3 ("drm/bridge: panel: Set pre_enable_prev_first from drmm_panel_bridge_add")
Reported-by: Svyatoslav Ryhel 
Closes: https://lore.kernel.org/dri-devel/CAPVz0n3YZass3Bns1m0XrFxtAC0DKbEPiW6vXimQx97G243sXw@mail.gmail.com/
Signed-off-by: Dmitry Baryshkov 
Reviewed-by: Neil Armstrong 
Signed-off-by: Neil Armstrong 
Link: https://lore.kernel.org/r/20250220-panel_prev_first-v1-1-b9e787825a1a@linaro.org

drm/bridge: samsung-dsim: Don't use %pK through printk

2025-06-29T09:05:51+00:00

In the past %pK was preferable to %p as it would not leak raw pointer
values into the kernel log.
Since commit ad67b74d2469 ("printk: hash addresses printed with %p")
the regular %p has been improved to avoid this issue.
Furthermore, restricted pointers ("%pK") were never meant to be used
through printk(). They can still unintentionally leak raw pointers or
acquire sleeping locks in atomic contexts.

Switch to the regular pointer formatting which is safer and
easier to reason about.

Signed-off-by: Thomas Weißschuh 
Signed-off-by: Inki Dae

drm/bridge: ti-sn65dsi86: Add HPD for DisplayPort connector type

2025-06-25T14:49:01+00:00

By default, HPD was disabled on SN65DSI86 bridge. When the driver was
added (commit "a095f15c00e27"), the HPD_DISABLE bit was set in pre-enable
call which was moved to other function calls subsequently.
Later on, commit "c312b0df3b13" added detect utility for DP mode. But with
HPD_DISABLE bit set, all the HPD events are disabled[0] and the debounced
state always return 1 (always connected state).

Set HPD_DISABLE bit conditionally based on display sink's connector type.
Since the HPD_STATE is reflected correctly only after waiting for debounce
time (~100-400ms) and adding this delay in detect() is not feasible
owing to the performace impact (glitches and frame drop), remove runtime
calls in detect() and add hpd_enable()/disable() bridge hooks with runtime
calls, to detect hpd properly without any delay.

[0]:  (Pg. 32)

Fixes: c312b0df3b13 ("drm/bridge: ti-sn65dsi86: Implement bridge connector operations for DP")
Cc: Max Krummenacher 
Reviewed-by: Douglas Anderson 
Tested-by: Ernest Van Hoecke 
Signed-off-by: Jayesh Choudhary 
Signed-off-by: Douglas Anderson 
Link: https://lore.kernel.org/r/20250624044835.165708-1-j-choudhary@ti.com