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+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/gpio/nxp,pcf8575.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: PCF857x-compatible I/O expanders
+
+maintainers:
+ - Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
+
+description:
+ The PCF857x-compatible chips have "quasi-bidirectional" I/O lines that can be
+ driven high by a pull-up current source or driven low to ground. This
+ combines the direction and output level into a single bit per line, which
+ can't be read back. We can't actually know at initialization time whether a
+ line is configured (a) as output and driving the signal low/high, or (b) as
+ input and reporting a low/high value, without knowing the last value written
+ since the chip came out of reset (if any). The only reliable solution for
+ setting up line direction is thus to do it explicitly.
+
+properties:
+ compatible:
+ enum:
+ - maxim,max7328
+ - maxim,max7329
+ - nxp,pca8574
+ - nxp,pca8575
+ - nxp,pca9670
+ - nxp,pca9671
+ - nxp,pca9672
+ - nxp,pca9673
+ - nxp,pca9674
+ - nxp,pca9675
+ - nxp,pcf8574
+ - nxp,pcf8574a
+ - nxp,pcf8575
+
+ reg:
+ maxItems: 1
+
+ gpio-controller: true
+
+ '#gpio-cells':
+ const: 2
+ description:
+ The first cell is the GPIO number and the second cell specifies GPIO
+ flags, as defined in <dt-bindings/gpio/gpio.h>. Only the GPIO_ACTIVE_HIGH
+ and GPIO_ACTIVE_LOW flags are supported.
+
+ lines-initial-states:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description:
+ Bitmask that specifies the initial state of each line.
+ When a bit is set to zero, the corresponding line will be initialized to
+ the input (pulled-up) state.
+ When the bit is set to one, the line will be initialized to the
+ low-level output state.
+ If the property is not specified all lines will be initialized to the
+ input state.
+
+ interrupts:
+ maxItems: 1
+
+ interrupt-controller: true
+
+ '#interrupt-cells':
+ const: 2
+
+ wakeup-source: true
+
+patternProperties:
+ "^(.+-hog(-[0-9]+)?)$":
+ type: object
+
+ required:
+ - gpio-hog
+
+required:
+ - compatible
+ - reg
+ - gpio-controller
+ - '#gpio-cells'
+
+additionalProperties: false
+
+examples:
+ - |
+ i2c {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ pcf8575: gpio@20 {
+ compatible = "nxp,pcf8575";
+ reg = <0x20>;
+ interrupt-parent = <&irqpin2>;
+ interrupts = <3 0>;
+ gpio-controller;
+ #gpio-cells = <2>;
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ };
+ };