• Benoit Parrot's avatar
    gpio: add GPIO hogging mechanism · f625d460
    Benoit Parrot authored
    Based on Boris Brezillion's work this is a reworked patch
    of his initial GPIO hogging mechanism.
    This patch provides a way to initially configure specific GPIO
    when the GPIO controller is probed.
    
    The actual DT scanning to collect the GPIO specific data is performed
    as part of gpiochip_add().
    
    The purpose of this is to allow specific GPIOs to be configured
    without any driver specific code.
    This is particularly useful because board design are getting
    increasingly complex and given SoC pins can now have more
    than 10 mux values, a lot of connections are now dependent on
    external IO muxes to switch various modes.
    
    Specific drivers should not necessarily need to be aware of
    what accounts to a specific board implementation. This board level
    "description" should be best kept as part of the dts file.
    Signed-off-by: default avatarBenoit Parrot <bparrot@ti.com>
    Reviewed-by: default avatarAlexandre Courbot <acourbot@nvidia.com>
    Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
    f625d460
gpiolib.c 60.2 KB