[RESENT,v3] dt-bindings: gpio: add common consumer GPIO lines

Typical GPIO lines like enable, powerdown, reset or wakeup are not
documented as common, which leads to new variations of these (e.g.
pwdn-gpios).  Add a common schema which serves also as a documentation
for preferred naming.

Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>

---

Reason for resend:
==================
Previously patch was on hold because richtek,rt4801 bindings were using
two GPIOs in "enable-gpios", so this schema would complain.  This was
resolved here:
https://lore.kernel.org/all/165089886500.211842.728549769223794277.b4-ty@kernel.org/

Changes since v2:
==================
1. Correct my email address.
2. Add Rob's review.

Changes since v1:
==================
1. Select-true, add maxItems and description for each entry (Rob).
2. Mention ACTIVE_LOW in bindings description (Linus).
3. Add allOf for pwrseq reset-gpios case.
---
 .../bindings/gpio/gpio-consumer-common.yaml   | 64 +++++++++++++++++++
 1 file changed, 64 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/gpio/gpio-consumer-common.yaml

On Mon, Apr 25, 2022 at 8:46 PM Krzysztof Kozlowski
<krzysztof.kozlowski@linaro.org> wrote:
>
> Typical GPIO lines like enable, powerdown, reset or wakeup are not
> documented as common, which leads to new variations of these (e.g.
> pwdn-gpios).  Add a common schema which serves also as a documentation
> for preferred naming.
>
> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> Reviewed-by: Rob Herring <robh@kernel.org>
>
> ---
>
> Reason for resend:
> ==================
> Previously patch was on hold because richtek,rt4801 bindings were using
> two GPIOs in "enable-gpios", so this schema would complain.  This was
> resolved here:
> https://lore.kernel.org/all/165089886500.211842.728549769223794277.b4-ty@kernel.org/
>
> Changes since v2:
> ==================
> 1. Correct my email address.
> 2. Add Rob's review.
>
> Changes since v1:
> ==================
> 1. Select-true, add maxItems and description for each entry (Rob).
> 2. Mention ACTIVE_LOW in bindings description (Linus).
> 3. Add allOf for pwrseq reset-gpios case.
> ---
>  .../bindings/gpio/gpio-consumer-common.yaml   | 64 +++++++++++++++++++
>  1 file changed, 64 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/gpio/gpio-consumer-common.yaml
>
> diff --git a/Documentation/devicetree/bindings/gpio/gpio-consumer-common.yaml b/Documentation/devicetree/bindings/gpio/gpio-consumer-common.yaml
> new file mode 100644
> index 000000000000..40d0be31e200
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/gpio/gpio-consumer-common.yaml
> @@ -0,0 +1,64 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/gpio/gpio-consumer-common.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Common GPIO lines
> +
> +maintainers:
> +  - Bartosz Golaszewski <brgl@bgdev.pl>
> +  - Linus Walleij <linus.walleij@linaro.org>
> +
> +description:
> +  Pay attention to using proper GPIO flag (e.g. GPIO_ACTIVE_LOW) for the GPIOs
> +  using inverted signal (e.g. RESETN).
> +
> +select: true
> +
> +properties:
> +  enable-gpios:
> +    maxItems: 1
> +    description:
> +      GPIO connected to the enable control pin.
> +
> +  reset-gpios:
> +    description:
> +      GPIO (or GPIOs for power sequence) connected to the device reset pin
> +      (e.g. RESET or RESETN).
> +
> +  powerdown-gpios:
> +    maxItems: 1
> +    description:
> +      GPIO connected to the power down pin (hardware power down or power cut,
> +      e.g. PD or PWDN).
> +
> +  pwdn-gpios:
> +    maxItems: 1
> +    description: Use powerdown-gpios
> +    deprecated: true
> +
> +  wakeup-gpios:
> +    maxItems: 1
> +    description:
> +      GPIO connected to the pin waking up the device from suspend or other
> +      power-saving modes.
> +
> +allOf:
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              - mmc-pwrseq-simple
> +    then:
> +      properties:
> +        reset-gpios:
> +          minItems: 1
> +          maxItems: 32
> +    else:
> +      properties:
> +        reset-gpios:
> +          maxItems: 1
> +
> +additionalProperties: true
> --
> 2.32.0
>

Applied, thanks!

Bart