Framebuffer drivers for devices with dedicated backlight are supposed to set struct fb_info.bl_dev to the backlight's respective device. Use the value to match backlight and framebuffer in the backlight core code. The code first tests against struct backlight_ops.check_ops. If this test succeeds, it performs the test against fbdev. So backlight drivers can override the later test as before. Fbdev's backlight support depends on CONFIG_FB_BACKLIGHT. To avoid ifdef in the code, the new helper fb_bl_device() returns the backlight device, or NULL if the config option has been disabled. The test in the backlight code will then do nothing. v4: * declare empty fb_bl_device() as static inline * export fb_bl_device() v3: * hide ifdef in fb_bl_device() (Lee) * no if-else blocks (Andy) Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Link: https://lore.kernel.org/r/20240305162425.23845-2-tzimmermann@suse.de Signed-off-by: Lee Jones <lee@kernel.org> |
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|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| io_uring | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| rust | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .editorconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| .rustfmt.toml | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README | ||
README
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.