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>

1 files changed, 27 insertions, 0 deletions

diff --git a/Documentation/driver-api/firmware/introduction.rst b/Documentation/driver-api/firmware/introduction.rst
new file mode 100644
index 000000000..211cb44eb
--- /dev/null
+++ b/Documentation/driver-api/firmware/introduction.rst
@@ -0,0 +1,27 @@
+============
+Introduction
+============
+
+The firmware API enables kernel code to request files required
+for functionality from userspace, the uses vary:
+
+* Microcode for CPU errata
+* Device driver firmware, required to be loaded onto device
+  microcontrollers
+* Device driver information data (calibration data, EEPROM overrides),
+  some of which can be completely optional.
+
+Types of firmware requests
+==========================
+
+There are two types of calls:
+
+* Synchronous
+* Asynchronous
+
+Which one you use vary depending on your requirements, the rule of thumb
+however is you should strive to use the asynchronous APIs unless you also
+are already using asynchronous initialization mechanisms which will not
+stall or delay boot. Even if loading firmware does not take a lot of time
+processing firmware might, and this can still delay boot or initialization,
+as such mechanisms such as asynchronous probe can help supplement drivers.