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, 52 insertions, 0 deletions

diff --git a/Documentation/fb/lxfb.rst b/Documentation/fb/lxfb.rst
new file mode 100644
index 000000000..0a176ab37
--- /dev/null
+++ b/Documentation/fb/lxfb.rst
@@ -0,0 +1,52 @@
+======================================
+lxfb - AMD Geode LX framebuffer driver
+======================================
+
+This is a graphics framebuffer driver for AMD Geode LX based processors.
+
+Advantages:
+
+ * No need to use AMD's VSA code (or other VESA emulation layer) in the
+   BIOS.
+ * It provides a nice large console (128 cols + 48 lines with 1024x768)
+   without using tiny, unreadable fonts.
+ * You can run XF68_FBDev on top of /dev/fb0
+ * Most important: boot logo :-)
+
+Disadvantages:
+
+ * graphic mode is slower than text mode...
+
+
+How to use it?
+==============
+
+Switching modes is done using  lxfb.mode_option=<resolution>... boot
+parameter or using `fbset` program.
+
+See Documentation/fb/modedb.rst for more information on modedb
+resolutions.
+
+
+X11
+===
+
+XF68_FBDev should generally work fine, but it is non-accelerated.
+
+
+Configuration
+=============
+
+You can pass kernel command line options to lxfb with lxfb.<option>.
+For example, lxfb.mode_option=800x600@75.
+Accepted options:
+
+================ ==================================================
+mode_option	 specify the video mode.  Of the form
+		 <x>x<y>[-<bpp>][@<refresh>]
+vram		 size of video ram (normally auto-detected)
+vt_switch	 enable vt switching during suspend/resume.  The vt
+		 switch is slow, but harmless.
+================ ==================================================
+
+Andres Salomon <dilinger@debian.org>