On Fri, Dec 1, 2017 at 2:44 PM, Quentin Schulz
[off-list ref] wrote:

The X-Powers AXP209 has 3 GPIOs. GPIO0/1 can each act either as a GPIO,
an ADC or a LDO regulator. GPIO2 can only act as a GPIO.

This adds the pinctrl features to the driver so GPIO0/1 can be used as
ADC or LDO regulator.

Signed-off-by: Quentin Schulz <redacted>
Acked-by: Rob Herring <robh@kernel.org>

Please add a reference to the generic pinctrl bindings and state that you
use them and how.

pinctrl/pinctrl-bindings.txt

+The GPIOs can be muxed to other functions and therefore, must be a subnode of
+axp_gpio.
+
+Example:
+
+&axp_gpio {
+       gpio0_adc: gpio0-adc {
+               pins = "GPIO0";
+               function = "adc";
+       };
+};

So write explicitly that this driver employs the per-pin muxing pattern.

Yours,
Linus Walleij