These are called when a GPIO is to be used as IRQ. Without these custom callbacks, when an interrupt is requested directly and not through gpiod_to_irq(), the request fails because the GPIO is not necesarily in input mode. These callbacks simply enforce that the requested GPIO is in input mode. Signed-off-by: Paul Cercueil <paul@crapouillou.net> Link: https://lore.kernel.org/r/20200503164549.163884-1-paul@crapouillou.net Signed-off-by: Linus Walleij <linus.walleij@linaro.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 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.
Description
Languages
C
97.6%
Assembly
1%
Shell
0.5%
Python
0.3%
Makefile
0.3%