6933ba529d
If a GPIO driver returns a positive integer from one of the direction setter callbacks, we'll end up propagating it to user-space. Whether we should sanitize the values returned by callbacks is a different question but let's first improve the documentation and fortify the contract with GPIO providers. Reported-by: José Guilherme de Castro Rodrigues <joseguilhermebh@hotmail.com> Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org> Reviewed-by: Kent Gibson <warthog618@gmail.com>