kernel/linux.git/drivers/gpu/drm/tegra/dc.c, branch v5.10.264

drm/tegra: dc: Fix device node reference leak in tegra_dc_has_output()

2026-07-24T13:48:57+00:00

[ Upstream commit 63a3998d792ab5c45304bf879e385a31fa923b61 ] The of_for_each_phandle() macro increments the reference count of the device node it iterates over. If the loop exits early, the reference must be released manually. In tegra_dc_has_output(), the function returns true immediately when a match is found, failing to release the current node's reference. Fix this by adding a call to of_node_put() before returning from the loop. Fixes: c57997bce423 ("drm/tegra: sor: Add Tegra186 support") Signed-off-by: Felix Gu Acked-by: Mikko Perttunen Signed-off-by: Thierry Reding Link: https://patch.msgid.link/20260128-dc-v1-1-a88205826301@gmail.com Signed-off-by: Sasha Levin

drm/tegra: dc: Fix reference leak in tegra_dc_couple()

2025-12-06T21:08:20+00:00

commit 4c5376b4b143c4834ebd392aef2215847752b16a upstream. driver_find_device() calls get_device() to increment the reference count once a matching device is found, but there is no put_device() to balance the reference count. To avoid reference count leakage, add put_device() to decrease the reference count. Found by code review. Cc: stable@vger.kernel.org Fixes: a31500fe7055 ("drm/tegra: dc: Restore coupling of display controllers") Signed-off-by: Ma Ke Acked-by: Mikko Perttunen Signed-off-by: Thierry Reding Link: https://patch.msgid.link/20251022114720.24937-1-make24@iscas.ac.cn Signed-off-by: Greg Kroah-Hartman

drm/tegra: Fix a possible null pointer dereference

2025-07-17T16:27:43+00:00

commit 780351a5f61416ed2ba1199cc57e4a076fca644d upstream. In tegra_crtc_reset(), new memory is allocated with kzalloc(), but no check is performed. Before calling __drm_atomic_helper_crtc_reset, state should be checked to prevent possible null pointer dereference. Fixes: b7e0b04ae450 ("drm/tegra: Convert to using __drm_atomic_helper_crtc_reset() for reset.") Cc: stable@vger.kernel.org Signed-off-by: Qiu-ji Chen Signed-off-by: Thierry Reding Link: https://lore.kernel.org/r/20241106095906.15247-1-chenqiuji666@gmail.com Signed-off-by: Greg Kroah-Hartman

drm/tegra: Assign plane type before registration

2025-07-17T16:27:43+00:00

commit 9ff4fdf4f44b69237c0afc1d3a8dac916ce66f3e upstream. Changes to a plane's type after it has been registered aren't propagated to userspace automatically. This could possibly be achieved by updating the property, but since we can already determine which type this should be before the registration, passing in the right type from the start is a much better solution. Suggested-by: Aaron Kling Signed-off-by: Thierry Reding Cc: stable@vger.kernel.org Fixes: 473079549f27 ("drm/tegra: dc: Add Tegra186 support") Signed-off-by: Aaron Kling Signed-off-by: Thierry Reding Link: https://lore.kernel.org/r/20250421-tegra-drm-primary-v2-1-7f740c4c2121@gmail.com Signed-off-by: Greg Kroah-Hartman

drm/tegra: Add missing clk_disable_unprepare() in tegra_dc_probe()

2023-01-14T09:15:33+00:00

[ Upstream commit 7ad4384d53c67672a8720cdc2ef638d7d1710ab8 ] Add the missing clk_disable_unprepare() before return from tegra_dc_probe() in the error handling path. Fixes: f68ba6912bd2 ("drm/tegra: dc: Link DC1 to DC0 on Tegra20") Signed-off-by: Zhang Zekun Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin

drm/tegra: Don't set allow_fb_modifiers explicitly

2021-07-19T07:44:58+00:00

commit be4306ad928fcf736cbe2616b6dd19d91f1bc083 upstream. Since commit 890880ddfdbe256083170866e49c87618b706ac7 Author: Paul Kocialkowski Date: Fri Jan 4 09:56:10 2019 +0100 drm: Auto-set allow_fb_modifiers when given modifiers at plane init this is done automatically as part of plane init, if drivers set the modifier list correctly. Which is the case here. It was slightly inconsistently though, since planes with only linear modifier support haven't listed that explicitly. Fix that, and cc: stable to allow userspace to rely on this. Again don't backport further than where Paul's patch got added. Cc: stable@vger.kernel.org # v5.1 + Cc: Pekka Paalanen Acked-by: Thierry Reding Signed-off-by: Daniel Vetter Cc: Thierry Reding Cc: Jonathan Hunter Cc: linux-tegra@vger.kernel.org Link: https://patchwork.freedesktop.org/patch/msgid/20210413094904.3736372-10-daniel.vetter@ffwll.ch Signed-off-by: Greg Kroah-Hartman

drm/tegra: dc: Don't set PLL clock to 0Hz

2021-04-16T09:43:20+00:00

[ Upstream commit f8fb97c915954fc6de6513cdf277103b5c6df7b3 ] RGB output doesn't allow to change parent clock rate of the display and PCLK rate is set to 0Hz in this case. The tegra_dc_commit_state() shall not set the display clock to 0Hz since this change propagates to the parent clock. The DISP clock is defined as a NODIV clock by the tegra-clk driver and all NODIV clocks use the CLK_SET_RATE_PARENT flag. This bug stayed unnoticed because by default PLLP is used as the parent clock for the display controller and PLLP silently skips the erroneous 0Hz rate changes because it always has active child clocks that don't permit rate changes. The PLLP isn't acceptable for some devices that we want to upstream (like Samsung Galaxy Tab and ASUS TF700T) due to a display panel clock rate requirements that can't be fulfilled by using PLLP and then the bug pops up in this case since parent clock is set to 0Hz, killing the display output. Don't touch DC clock if pclk=0 in order to fix the problem. Signed-off-by: Dmitry Osipenko Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin

drm/tegra: dc: Restore coupling of display controllers

2021-04-07T13:00:11+00:00

commit a31500fe7055451ed9043c8fff938dfa6f70ee37 upstream. Coupling of display controllers used to rely on runtime PM to take the companion controller out of reset. Commit fd67e9c6ed5a ("drm/tegra: Do not implement runtime PM") accidentally broke this when runtime PM was removed. Restore this functionality by reusing the hierarchical host1x client suspend/resume infrastructure that's similar to runtime PM and which perfectly fits this use-case. Fixes: fd67e9c6ed5a ("drm/tegra: Do not implement runtime PM") Reported-by: Dmitry Osipenko Reported-by: Paul Fertser Tested-by: Dmitry Osipenko Signed-off-by: Thierry Reding Signed-off-by: Greg Kroah-Hartman

drm/tegra: Fix reference leak when pm_runtime_get_sync() fails

2021-03-04T10:37:42+00:00

[ Upstream commit dcdfe2712b68f1e9dbf4f1a96ad59b80e5cc0ef7 ] The PM reference count is not expected to be incremented on return in these Tegra functions. However, pm_runtime_get_sync() will increment the PM reference count even on failure. Forgetting to put the reference again will result in a leak. Replace it with pm_runtime_resume_and_get() to keep the usage counter balanced. Fixes: fd67e9c6ed5a ("drm/tegra: Do not implement runtime PM") Reported-by: Hulk Robot Signed-off-by: Qinglang Miao Signed-off-by: Thierry Reding Signed-off-by: Sasha Levin

treewide: Use fallthrough pseudo-keyword

2020-08-23T22:36:59+00:00

Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva