This adds bindings for a GPIO enable/disable delay driver. Signed-off-by: Alexander Stein <alexander.stein@xxxxxxxxxxxxxxx> --- .../devicetree/bindings/gpio/gpio-delay.yaml | 75 +++++++++++++++++++ 1 file changed, 75 insertions(+) create mode 100644 Documentation/devicetree/bindings/gpio/gpio-delay.yaml diff --git a/Documentation/devicetree/bindings/gpio/gpio-delay.yaml b/Documentation/devicetree/bindings/gpio/gpio-delay.yaml new file mode 100644 index 000000000000..20871356e9b5 --- /dev/null +++ b/Documentation/devicetree/bindings/gpio/gpio-delay.yaml @@ -0,0 +1,75 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/gpio/gpio-delay.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: GPIO delay controller + +maintainers: + - Alexander Stein <linux@xxxxxxxxxxxxxxx> + +description: | + This binding describes an electrical setup where setting an GPIO output + is delayed by some external setup, e.g. RC curcuit. + + +----------+ +-----------+ + | | VCC_B | | + | | | | | + | | VCC_A _ | | + | GPIO | | | R | Consumer | + |controller| ___ |_| | | + | | | | | | | + | [IOx|-------| |--+-----|-----+ | + | | |___| | | input | + | | | | | + +----------+ --- C +-----------+ + --- + | + - + GND + + If the input on the consumer is controlled by an open-drain signal + attached to an RC curcuit the ramp-up delay is not under control + of the GPIO controller. + +properties: + compatible: + const: gpio-delay + + "#gpio-cells": + description: | + Specifies the pin, ramp-up and ramp-down delays. The + delays are specified in microseconds. + const: 3 + + input-gpios: + description: Array of GPIOs which output signal change is delayed + + gpio-controller: true + + gpio-line-names: true + +required: + - compatible + - "#gpio-cells" + - gpio-controller + - input-gpios + +additionalProperties: false + +examples: + - | + #include <dt-bindings/gpio/gpio.h> + + enable_delay: enable-delay { + compatible = "gpio-delay"; + #gpio-cells = <3>; + gpio-controller; + input-gpios = <&gpio0 3 GPIO_ACTIVE_LOW>, + <&gpio3 1 GPIO_ACTIVE_HIGH>; + }; + + consumer { + enable-gpios = <&enable_delay 0 130000 30000>; + }; -- 2.34.1
