pinctrl: pinmux: Add missing .function_is_gpio kerneldoc

This callback was undocumented, add the docs.

Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/include/linux/pinctrl/pinmux.h b/include/linux/pinctrl/pinmux.h
index 6db6c3e1ccc2249d4b4204e6fc19bf7b4397cc81..094bbe2fd6fd5ea3c5fdf5b6d6d9a7639700b50b 100644 (file)
--- a/include/linux/pinctrl/pinmux.h
+++ b/include/linux/pinctrl/pinmux.h
@@ -35,6 +35,16 @@ struct pinctrl_gpio_range;
  *     name can be used with the generic @pinctrl_ops to retrieve the
  *     actual pins affected. The applicable groups will be returned in
  *     @groups and the number of groups in @num_groups
+ * @function_is_gpio: determine if the indicated function selector passed
+ *     corresponds to the GPIO function which is used by the accelerated GPIO
+ *     functions @gpio_request_enable, @gpio_disable_free and
+ *     @gpio_set_direction. When the pin control core can properly determine
+ *     if a function is a GPIO function, it is easier to use the @strict mode
+ *     on the pin controller. Since a single function is passed, this is
+ *     only useful on pin controllers that use a specific function for GPIO,
+ *     and that usually presupposes that a one-group-per-pin approach is
+ *     used, so that a single function can be set on a single pin to turn
+ *     it to GPIO mode.
  * @set_mux: enable a certain muxing function with a certain pin group. The
  *     driver does not need to figure out whether enabling this function
  *     conflicts some other use of the pins in that group, such collisions