08f441360f
When you create a submenu using the 'menu' syntax, there is no
ambiguity about its end because the code between 'menu' and 'endmenu'
becomes the submenu.
In contrast, 'menuconfig' does not have the corresponding end marker.
Instead, the end of the submenu is inferred from symbol dependencies.
This is detailed in Documentation/kbuild/kconfig-language.rst, starting
line 348. It outlines two methods to place the code under the submenu:
(1) Open an if-block immediately after 'menuconfig', enclosing the
submenu content within it
(2) Add 'depends on' to every symbol intended for the submenu
Many subsystems opt for (1) because it reliably maintains the submenu
structure.
The DRM subsystem adopts (2). The submenu ends when the sequence of
'depends on DRM' breaks. It can be confirmed by running a GUI frontend
such as 'make menuconfig' and visiting the DRM menu:
< > Direct Rendering Manager (XFree86 4.1.0 and higher DRI support) ----
If you toggle this, you will notice most of the DRM-related options
appear below it, not in the submenu.
I highly recommend the approach (1). Obviously, (2) is not reliable,
as the submenu breaks whenever someone forgets to add 'depends on DRM'.
This commit encloses the entire DRM configuration with 'if DRM' and
'endif', except for DRM_PANEL_ORIENTATION_QUIRKS.
Note:
Now, 'depends on DRM' properties inside the if-block are all redundant.
I leave it as follow-up cleanups.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20240426135602.2500125-1-masahiroy@kernel.org
Signed-off-by: Maxime Ripard <mripard@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the reStructuredText markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.