01f4fbb3bd
Initialize the instance of struct fb_ops with fbdev initializer macros for framebuffers in DMA-able virtual address space. Set the read/write, draw and mmap callbacks to the correct implementation and avoid implicit defaults. Also select the necessary helpers in Kconfig. The driver uses a mixture of DMA helpers and deferred I/O. That probably needs fixing by a driver maintainer. Fbdev drivers sometimes rely on the callbacks being NULL for a default I/O-memory-based implementation to be invoked; hence requiring the I/O helpers to be built in any case. Setting all callbacks in all drivers explicitly will allow to make the I/O helpers optional. This benefits systems that do not use these functions. Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Link: https://patchwork.freedesktop.org/patch/msgid/20231127131655.4020-14-tzimmermann@suse.de
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 Restructured Text 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.