[RFC 4/4] dt-bindings: gpio: Add bindings for SCMI pinctrl based gpio

[AKASHI Takahiro <takahiro.akashi@linaro.org>]

A dt binding for SCMI pinctrl based gpio driver is defined in this
commit. It basically conforms to generic pinctrl-gpio mapping framework.

Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
---
 .../bindings/gpio/arm,scmi-gpio.yaml          | 71 +++++++++++++++++++
 1 file changed, 71 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/gpio/arm,scmi-gpio.yaml

diff --git a/Documentation/devicetree/bindings/gpio/arm,scmi-gpio.yaml b/Documentation/devicetree/bindings/gpio/arm,scmi-gpio.yaml
new file mode 100644
index 000000000000..2601c5594567
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/arm,scmi-gpio.yaml
@@ -0,0 +1,71 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/gpio/arm,scmi-gpio.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: SCMI pinctrl based generic GPIO controller
+
+maintainers:
+  - AKASHI Takahiro <akashi.takahiro@linaro.org>
+
+properties:
+  $nodename:
+    pattern: "^scmi_gpio(@[0-9a-f]+)$"
+
+  compatible:
+    const: arm,scmi-gpio-generic
+
+  gpio-controller: true
+
+  "#gpio-cells":
+    const: 2
+
+  gpio-ranges: true
+
+  gpio-ranges-group-names: true
+
+patternProperties:
+  "^.+-hog(-[0-9]+)?$":
+    type: object
+    properties:
+      gpio-hog: true
+      gpios: true
+      input: true
+      output-high: true
+      output-low: true
+      line-name: true
+
+    required:
+      - gpio-hog
+      - gpios
+
+    additionalProperties: false
+
+required:
+  - compatible
+  - gpio-controller
+  - "#gpio-cells"
+  - gpio-ranges
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    scmi_gpio_0: scmi_gpio@0 {
+        compatible = "arm,scmi-gpio";
+        gpio-controller;
+        #gpio-cells = <2>;
+        gpio-ranges = <&scmi_pinctrl 0 10 5>,
+                      <&scmi_pinctrl 5 0 0>;
+        gpio-ranges-group-names = "",
+                                  "pinmux_gpio";
+    };
+
+    // Consumer:
+    sdhci0_pwrseq {
+        compatible = "mmc-pwrseq-emmc";
+        reset-gpios = <&scmi_gpio_0 0 GPIO_ACTIVE_LOW>;
+    };
-- 
2.34.1