• Stephen Warren's avatar
    Documentation/gpio.txt: Explain expected pinctrl interaction · 0dc665d4
    Stephen Warren authored
    Update gpio.txt based on recent discussions regarding interaction with the
    pinctrl subsystem.
    
    Previously, gpio_request() was described as explicitly not performing any
    required mux setup operations etc.
    
    Now, gpio_request() is explicitly as explicitly performing any required mux
    setup operations where possible. In the case it isn't, platform code is
    required to have set up any required muxing or other configuration prior to
    gpio_request() being called, in order to maintain the same semantics.
    
    This is achieved by gpiolib drivers calling e.g. pinctrl_request_gpio() in
    their .request() operation.
    
    Cc: Randy Dunlap <rdunlap@xenotime.net>
    Cc: linux-doc@vger.kernel.org
    Signed-off-by: default avatarStephen Warren <swarren@nvidia.com>
    Reviewed-by: default avatarLinus Walleij <linus.walleij@linaro.org>
    Signed-off-by: default avatarGrant Likely <grant.likely@secretlab.ca>
    0dc665d4
gpio.txt 32.2 KB