summaryrefslogtreecommitdiffstats
path: root/Documentation/admin-guide/video-output.rst
diff options
context:
space:
mode:
authorHaojie Li <lihaojie@kylinos.cn>2026-08-25 18:08:45 +0800
committerChun-Kuang Hu <chunkuang.hu@kernel.org>2026-09-28 23:20:55 +0000
commitbce7698e2e6565bb765bd0522337f29f5f312624 (patch)
tree0b735b7b4a27369cb4d75d9431b3ee59ce7e5bcc /Documentation/admin-guide/video-output.rst
downloadlinux-stable-bce7698e2e6565bb765bd0522337f29f5f312624.tar.gz
linux-stable-bce7698e2e6565bb765bd0522337f29f5f312624.zip
drm/mediatek: Add missing IS_ERR check for ovl_adaptor platform devicegrafted
platform_device_register_data() can fail and return an ERR_PTR, but the return value is used without checking, leading to an invalid pointer being stored in ddp_comp[].dev and passed to component_match_add() and mtk_ddp_comp_init(), which could result in a kernel crash. Add an IS_ERR() check to jump to the error handling path on failure. Fixes: 0d9eee9118b7 ("drm/mediatek: Add drm ovl_adaptor sub driver for MT8195") Cc: stable@vger.kernel.org Signed-off-by: Haojie Li <lihaojie@kylinos.cn> Reviewed-by: CK Hu <ck.hu@mediatek.com> Link: https://patchwork.kernel.org/project/linux-mediatek/patch/20260825100845.438893-1-lihaojie@kylinos.cn/ Signed-off-by: Chun-Kuang Hu <chunkuang.hu@kernel.org>
Diffstat (limited to 'Documentation/admin-guide/video-output.rst')
-rw-r--r--Documentation/admin-guide/video-output.rst34
1 files changed, 34 insertions, 0 deletions
diff --git a/Documentation/admin-guide/video-output.rst b/Documentation/admin-guide/video-output.rst
new file mode 100644
index 000000000..56d6fa2e2
--- /dev/null
+++ b/Documentation/admin-guide/video-output.rst
@@ -0,0 +1,34 @@
+Video Output Switcher Control
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+2006 luming.yu@intel.com
+
+The output sysfs class driver provides an abstract video output layer that
+can be used to hook platform specific methods to enable/disable video output
+device through common sysfs interface. For example, on my IBM ThinkPad T42
+laptop, The ACPI video driver registered its output devices and read/write
+method for 'state' with output sysfs class. The user interface under sysfs is::
+
+ linux:/sys/class/video_output # tree .
+ .
+ |-- CRT0
+ | |-- device -> ../../../devices/pci0000:00/0000:00:01.0
+ | |-- state
+ | |-- subsystem -> ../../../class/video_output
+ | `-- uevent
+ |-- DVI0
+ | |-- device -> ../../../devices/pci0000:00/0000:00:01.0
+ | |-- state
+ | |-- subsystem -> ../../../class/video_output
+ | `-- uevent
+ |-- LCD0
+ | |-- device -> ../../../devices/pci0000:00/0000:00:01.0
+ | |-- state
+ | |-- subsystem -> ../../../class/video_output
+ | `-- uevent
+ `-- TV0
+ |-- device -> ../../../devices/pci0000:00/0000:00:01.0
+ |-- state
+ |-- subsystem -> ../../../class/video_output
+ `-- uevent
+