dt-bindings: mux: Convert mux controller bindings to schema

Convert the mux controller bindings to DT schema.

Cc: Peter Rosin <peda@axentia.se>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Acked-by: Wolfram Sang <wsa@kernel.org>
Acked-by: Peter Rosin <peda@axentia.se>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20210526184839.2937899-4-robh@kernel.org

9 files changed, 465 insertions, 357 deletions

diff --git a/Documentation/devicetree/bindings/mux/adi,adg792a.txt b/Documentation/devicetree/bindings/mux/adi,adg792a.txt
index 96b787a69f50..b0e5bf6903d8 100644
--- a/Documentation/devicetree/bindings/mux/adi,adg792a.txt
+++ b/Documentation/devicetree/bindings/mux/adi,adg792a.txt
@@ -5,7 +5,7 @@ Required properties:
 - #mux-control-cells : <0> if parallel (the three muxes are bound together
   with a single mux controller controlling all three muxes), or <1> if
   not (one mux controller for each mux).
-* Standard mux-controller bindings as described in mux-controller.txt
+* Standard mux-controller bindings as described in mux-controller.yaml
 
 Optional properties for ADG792G:
 - gpio-controller : if present, #gpio-cells below is required.
diff --git a/Documentation/devicetree/bindings/mux/adi,adgs1408.txt b/Documentation/devicetree/bindings/mux/adi,adgs1408.txt
index be6947f4d86b..453a38961c13 100644
--- a/Documentation/devicetree/bindings/mux/adi,adgs1408.txt
+++ b/Documentation/devicetree/bindings/mux/adi,adgs1408.txt
@@ -4,7 +4,7 @@ Required properties:
 - compatible : Should be one of
 	* "adi,adgs1408"
 	* "adi,adgs1409"
-* Standard mux-controller bindings as described in mux-controller.txt
+* Standard mux-controller bindings as described in mux-controller.yaml
 
 Optional properties for ADGS1408/1409:
 - gpio-controller : if present, #gpio-cells is required.
diff --git a/Documentation/devicetree/bindings/mux/gpio-mux.txt b/Documentation/devicetree/bindings/mux/gpio-mux.txt
deleted file mode 100644
index b8f746344d80..000000000000
--- a/Documentation/devicetree/bindings/mux/gpio-mux.txt
+++ /dev/null
@@ -1,69 +0,0 @@
-GPIO-based multiplexer controller bindings
-
-Define what GPIO pins are used to control a multiplexer. Or several
-multiplexers, if the same pins control more than one multiplexer.
-
-Required properties:
-- compatible : "gpio-mux"
-- mux-gpios : list of gpios used to control the multiplexer, least
-	      significant bit first.
-- #mux-control-cells : <0>
-* Standard mux-controller bindings as decribed in mux-controller.txt
-
-Optional properties:
-- idle-state : if present, the state the mux will have when idle. The
-	       special state MUX_IDLE_AS_IS is the default.
-
-The multiplexer state is defined as the number represented by the
-multiplexer GPIO pins, where the first pin is the least significant
-bit. An active pin is a binary 1, an inactive pin is a binary 0.
-
-Example:
-
-	mux: mux-controller {
-		compatible = "gpio-mux";
-		#mux-control-cells = <0>;
-
-		mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
-			    <&pioA 1 GPIO_ACTIVE_HIGH>;
-	};
-
-	adc-mux {
-		compatible = "io-channel-mux";
-		io-channels = <&adc 0>;
-		io-channel-names = "parent";
-
-		mux-controls = <&mux>;
-
-		channels = "sync-1", "in", "out", "sync-2";
-	};
-
-	i2c-mux {
-		compatible = "i2c-mux";
-		i2c-parent = <&i2c1>;
-
-		mux-controls = <&mux>;
-
-		#address-cells = <1>;
-		#size-cells = <0>;
-
-		i2c@0 {
-			reg = <0>;
-			#address-cells = <1>;
-			#size-cells = <0>;
-
-			ssd1307: oled@3c {
-				/* ... */
-			};
-		};
-
-		i2c@3 {
-			reg = <3>;
-			#address-cells = <1>;
-			#size-cells = <0>;
-
-			pca9555: pca9555@20 {
-				/* ... */
-			};
-		};
-	};
diff --git a/Documentation/devicetree/bindings/mux/gpio-mux.yaml b/Documentation/devicetree/bindings/mux/gpio-mux.yaml
new file mode 100644
index 000000000000..0a7c8d64981a
--- /dev/null
+++ b/Documentation/devicetree/bindings/mux/gpio-mux.yaml
@@ -0,0 +1,92 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mux/gpio-mux.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: GPIO-based multiplexer controller bindings
+
+maintainers:
+  - Peter Rosin <peda@axentia.se>
+
+description: |+
+  Define what GPIO pins are used to control a multiplexer. Or several
+  multiplexers, if the same pins control more than one multiplexer.
+
+  The multiplexer state is defined as the number represented by the
+  multiplexer GPIO pins, where the first pin is the least significant
+  bit. An active pin is a binary 1, an inactive pin is a binary 0.
+
+properties:
+  compatible:
+    const: gpio-mux
+
+  mux-gpios:
+    description:
+      List of gpios used to control the multiplexer, least significant bit first.
+
+  '#mux-control-cells':
+    const: 0
+
+  idle-state:
+    default: -1
+
+required:
+  - compatible
+  - mux-gpios
+  - "#mux-control-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    mux: mux-controller {
+        compatible = "gpio-mux";
+        #mux-control-cells = <0>;
+
+        mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+              <&pioA 1 GPIO_ACTIVE_HIGH>;
+    };
+
+    adc-mux {
+        compatible = "io-channel-mux";
+        io-channels = <&adc 0>;
+        io-channel-names = "parent";
+
+        mux-controls = <&mux>;
+
+        channels = "sync-1", "in", "out", "sync-2";
+    };
+
+    i2c-mux {
+        compatible = "i2c-mux";
+        i2c-parent = <&i2c1>;
+
+        mux-controls = <&mux>;
+
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        i2c@0 {
+            reg = <0>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            ssd1307: oled@3c {
+                reg = <0x3c>;
+            };
+        };
+
+        i2c@3 {
+            reg = <3>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            pca9555: pca9555@20 {
+                reg = <0x20>;
+            };
+        };
+    };
+...
diff --git a/Documentation/devicetree/bindings/mux/mux-consumer.yaml b/Documentation/devicetree/bindings/mux/mux-consumer.yaml
new file mode 100644
index 000000000000..7af93298ab5c
--- /dev/null
+++ b/Documentation/devicetree/bindings/mux/mux-consumer.yaml
@@ -0,0 +1,46 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mux/mux-consumer.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Common multiplexer controller consumer bindings
+
+maintainers:
+  - Peter Rosin <peda@axentia.se>
+
+description: |
+  Mux controller consumers should specify a list of mux controllers that they
+  want to use with a property containing a 'mux-ctrl-list':
+
+    mux-ctrl-list ::= <single-mux-ctrl> [mux-ctrl-list]
+    single-mux-ctrl ::= <mux-ctrl-phandle> [mux-ctrl-specifier]
+    mux-ctrl-phandle : phandle to mux controller node
+    mux-ctrl-specifier : array of #mux-control-cells specifying the
+                         given mux controller (controller specific)
+
+  Mux controller properties should be named "mux-controls". The exact meaning of
+  each mux controller property must be documented in the device tree binding for
+  each consumer. An optional property "mux-control-names" may contain a list of
+  strings to label each of the mux controllers listed in the "mux-controls"
+  property.
+
+  mux-ctrl-specifier typically encodes the chip-relative mux controller number.
+  If the mux controller chip only provides a single mux controller, the
+  mux-ctrl-specifier can typically be left out.
+
+select: true
+
+properties:
+  mux-controls:
+    $ref: /schemas/types.yaml#/definitions/phandle-array
+
+  mux-control-names:
+    description:
+      Devices that use more than a single mux controller can use the
+      "mux-control-names" property to map the name of the requested mux
+      controller to an index into the list given by the "mux-controls" property.
+
+additionalProperties: true
+
+...
diff --git a/Documentation/devicetree/bindings/mux/mux-controller.txt b/Documentation/devicetree/bindings/mux/mux-controller.txt
deleted file mode 100644
index 4f47e4bd2fa0..000000000000
--- a/Documentation/devicetree/bindings/mux/mux-controller.txt
+++ /dev/null
@@ -1,157 +0,0 @@
-Common multiplexer controller bindings
-======================================
-
-A multiplexer (or mux) controller will have one, or several, consumer devices
-that uses the mux controller. Thus, a mux controller can possibly control
-several parallel multiplexers. Presumably there will be at least one
-multiplexer needed by each consumer, but a single mux controller can of course
-control several multiplexers for a single consumer.
-
-A mux controller provides a number of states to its consumers, and the state
-space is a simple zero-based enumeration. I.e. 0-1 for a 2-way multiplexer,
-0-7 for an 8-way multiplexer, etc.
-
-
-Consumers
----------
-
-Mux controller consumers should specify a list of mux controllers that they
-want to use with a property containing a 'mux-ctrl-list':
-
-	mux-ctrl-list ::= <single-mux-ctrl> [mux-ctrl-list]
-	single-mux-ctrl ::= <mux-ctrl-phandle> [mux-ctrl-specifier]
-	mux-ctrl-phandle : phandle to mux controller node
-	mux-ctrl-specifier : array of #mux-control-cells specifying the
-			     given mux controller (controller specific)
-
-Mux controller properties should be named "mux-controls". The exact meaning of
-each mux controller property must be documented in the device tree binding for
-each consumer. An optional property "mux-control-names" may contain a list of
-strings to label each of the mux controllers listed in the "mux-controls"
-property.
-
-Drivers for devices that use more than a single mux controller can use the
-"mux-control-names" property to map the name of the requested mux controller
-to an index into the list given by the "mux-controls" property.
-
-mux-ctrl-specifier typically encodes the chip-relative mux controller number.
-If the mux controller chip only provides a single mux controller, the
-mux-ctrl-specifier can typically be left out.
-
-Example:
-
-	/* One consumer of a 2-way mux controller (one GPIO-line) */
-	mux: mux-controller {
-		compatible = "gpio-mux";
-		#mux-control-cells = <0>;
-
-		mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>;
-	};
-
-	adc-mux {
-		compatible = "io-channel-mux";
-		io-channels = <&adc 0>;
-		io-channel-names = "parent";
-
-		mux-controls = <&mux>;
-		mux-control-names = "adc";
-
-		channels = "sync", "in";
-	};
-
-Note that in the example above, specifying the "mux-control-names" is redundant
-because there is only one mux controller in the list. However, if the driver
-for the consumer node in fact asks for a named mux controller, that name is of
-course still required.
-
-	/*
-	 * Two consumers (one for an ADC line and one for an i2c bus) of
-	 * parallel 4-way multiplexers controlled by the same two GPIO-lines.
-	 */
-	mux: mux-controller {
-		compatible = "gpio-mux";
-		#mux-control-cells = <0>;
-
-		mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
-			    <&pioA 1 GPIO_ACTIVE_HIGH>;
-	};
-
-	adc-mux {
-		compatible = "io-channel-mux";
-		io-channels = <&adc 0>;
-		io-channel-names = "parent";
-
-		mux-controls = <&mux>;
-
-		channels = "sync-1", "in", "out", "sync-2";
-	};
-
-	i2c-mux {
-		compatible = "i2c-mux";
-		i2c-parent = <&i2c1>;
-
-		mux-controls = <&mux>;
-
-		#address-cells = <1>;
-		#size-cells = <0>;
-
-		i2c@0 {
-			reg = <0>;
-			#address-cells = <1>;
-			#size-cells = <0>;
-
-			ssd1307: oled@3c {
-				/* ... */
-			};
-		};
-
-		i2c@3 {
-			reg = <3>;
-			#address-cells = <1>;
-			#size-cells = <0>;
-
-			pca9555: pca9555@20 {
-				/* ... */
-			};
-		};
-	};
-
-
-Mux controller nodes
---------------------
-
-Mux controller nodes must specify the number of cells used for the
-specifier using the '#mux-control-cells' property.
-
-Optionally, mux controller nodes can also specify the state the mux should
-have when it is idle. The idle-state property is used for this. If the
-idle-state is not present, the mux controller is typically left as is when
-it is idle. For multiplexer chips that expose several mux controllers, the
-idle-state property is an array with one idle state for each mux controller.
-
-The special value (-1) may be used to indicate that the mux should be left
-as is when it is idle. This is the default, but can still be useful for
-mux controller chips with more than one mux controller, particularly when
-there is a need to "step past" a mux controller and set some other idle
-state for a mux controller with a higher index.
-
-Some mux controllers have the ability to disconnect the input/output of the
-multiplexer. Using this disconnected high-impedance state as the idle state
-is indicated with idle state (-2).
-
-These constants are available in
-
-      #include <dt-bindings/mux/mux.h>
-
-as MUX_IDLE_AS_IS (-1) and MUX_IDLE_DISCONNECT (-2).
-
-An example mux controller node look like this (the adg972a chip is a triple
-4-way multiplexer):
-
-	mux: mux-controller@50 {
-		compatible = "adi,adg792a";
-		reg = <0x50>;
-		#mux-control-cells = <1>;
-
-		idle-state = <MUX_IDLE_DISCONNECT MUX_IDLE_AS_IS 2>;
-	};
diff --git a/Documentation/devicetree/bindings/mux/mux-controller.yaml b/Documentation/devicetree/bindings/mux/mux-controller.yaml
new file mode 100644
index 000000000000..736a84c3b6a5
--- /dev/null
+++ b/Documentation/devicetree/bindings/mux/mux-controller.yaml
@@ -0,0 +1,182 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mux/mux-controller.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Common multiplexer controller provider bindings
+
+maintainers:
+  - Peter Rosin <peda@axentia.se>
+
+description: |
+  A multiplexer (or mux) controller will have one, or several, consumer devices
+  that uses the mux controller. Thus, a mux controller can possibly control
+  several parallel multiplexers. Presumably there will be at least one
+  multiplexer needed by each consumer, but a single mux controller can of course
+  control several multiplexers for a single consumer.
+
+  A mux controller provides a number of states to its consumers, and the state
+  space is a simple zero-based enumeration. I.e. 0-1 for a 2-way multiplexer,
+  0-7 for an 8-way multiplexer, etc.
+
+
+  Mux controller nodes
+  --------------------
+
+  Mux controller nodes must specify the number of cells used for the
+  specifier using the '#mux-control-cells' property.
+
+  Optionally, mux controller nodes can also specify the state the mux should
+  have when it is idle. The idle-state property is used for this. If the
+  idle-state is not present, the mux controller is typically left as is when
+  it is idle. For multiplexer chips that expose several mux controllers, the
+  idle-state property is an array with one idle state for each mux controller.
+
+  The special value (-1) may be used to indicate that the mux should be left
+  as is when it is idle. This is the default, but can still be useful for
+  mux controller chips with more than one mux controller, particularly when
+  there is a need to "step past" a mux controller and set some other idle
+  state for a mux controller with a higher index.
+
+  Some mux controllers have the ability to disconnect the input/output of the
+  multiplexer. Using this disconnected high-impedance state as the idle state
+  is indicated with idle state (-2).
+
+  These constants are available in
+
+        #include <dt-bindings/mux/mux.h>
+
+  as MUX_IDLE_AS_IS (-1) and MUX_IDLE_DISCONNECT (-2).
+
+  An example mux controller node look like this (the adg972a chip is a triple
+  4-way multiplexer):
+
+    mux: mux-controller@50 {
+      compatible = "adi,adg792a";
+      reg = <0x50>;
+      #mux-control-cells = <1>;
+
+      idle-state = <MUX_IDLE_DISCONNECT MUX_IDLE_AS_IS 2>;
+    };
+
+select:
+  anyOf:
+    - properties:
+        $nodename:
+          pattern: '^mux-controller'
+    - required:
+        - '#mux-control-cells'
+
+properties:
+  $nodename:
+    pattern: '^mux-controller(@.*|-[0-9a-f]+)?$'
+
+  '#mux-control-cells':
+    enum: [ 0, 1 ]
+
+  idle-state:
+    $ref: /schemas/types.yaml#/definitions/int32
+    minimum: -2
+
+  idle-states:
+    description: |
+      Mux controller nodes can specify the state the mux should have when it is
+      idle. If the idle-state is not present, the mux controller is typically
+      left as is when it is idle. For multiplexer chips that expose several mux
+      controllers, the idle-state property is an array with one idle state for
+      each mux controller.
+
+      The special value (-1) may be used to indicate that the mux should be left
+      as is when it is idle. This is the default, but can still be useful for
+      mux controller chips with more than one mux controller, particularly when
+      there is a need to "step past" a mux controller and set some other idle
+      state for a mux controller with a higher index.
+
+      Some mux controllers have the ability to disconnect the input/output of the
+      multiplexer. Using this disconnected high-impedance state as the idle state
+      is indicated with idle state (-2).
+    $ref: /schemas/types.yaml#/definitions/int32-array
+    items:
+      minimum: -2
+
+additionalProperties: true
+
+examples:
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    /* One consumer of a 2-way mux controller (one GPIO-line) */
+    mux: mux-controller {
+        compatible = "gpio-mux";
+        #mux-control-cells = <0>;
+
+        mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>;
+    };
+
+    adc-mux {
+        compatible = "io-channel-mux";
+        io-channels = <&adc 0>;
+        io-channel-names = "parent";
+
+        mux-controls = <&mux>;
+        mux-control-names = "adc";
+
+        channels = "sync", "in";
+    };
+
+  - |
+    #include <dt-bindings/gpio/gpio.h>
+
+    /*
+     * Two consumers (one for an ADC line and one for an i2c bus) of
+     * parallel 4-way multiplexers controlled by the same two GPIO-lines.
+     */
+    mux2: mux-controller {
+        compatible = "gpio-mux";
+        #mux-control-cells = <0>;
+
+        mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+              <&pioA 1 GPIO_ACTIVE_HIGH>;
+    };
+
+    adc-mux {
+        compatible = "io-channel-mux";
+        io-channels = <&adc 0>;
+        io-channel-names = "parent";
+
+        mux-controls = <&mux2>;
+
+        channels = "sync-1", "in", "out", "sync-2";
+    };
+
+    i2c-mux {
+        compatible = "i2c-mux";
+        i2c-parent = <&i2c1>;
+
+        mux-controls = <&mux2>;
+
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        i2c@0 {
+            reg = <0>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            ssd1307: oled@3c {
+                reg = <0x3c>;
+            };
+        };
+
+        i2c@3 {
+            reg = <3>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            pca9555: pca9555@20 {
+                reg = <0x20>;
+            };
+        };
+    };
+...
diff --git a/Documentation/devicetree/bindings/mux/reg-mux.txt b/Documentation/devicetree/bindings/mux/reg-mux.txt
deleted file mode 100644
index 4afd7ba73d60..000000000000
--- a/Documentation/devicetree/bindings/mux/reg-mux.txt
+++ /dev/null
@@ -1,129 +0,0 @@
-Generic register bitfield-based multiplexer controller bindings
-
-Define register bitfields to be used to control multiplexers. The parent
-device tree node must be a device node to provide register r/w access.
-
-Required properties:
-- compatible : should be one of
-	"reg-mux" : if parent device of mux controller is not syscon device
-	"mmio-mux" : if parent device of mux controller is syscon device
-- #mux-control-cells : <1>
-- mux-reg-masks : an array of register offset and pre-shifted bitfield mask
-                  pairs, each describing a single mux control.
-* Standard mux-controller bindings as decribed in mux-controller.txt
-
-Optional properties:
-- idle-states : if present, the state the muxes will have when idle. The
-		special state MUX_IDLE_AS_IS is the default.
-
-The multiplexer state of each multiplexer is defined as the value of the
-bitfield described by the corresponding register offset and bitfield mask
-pair in the mux-reg-masks array.
-
-Example 1:
-The parent device of mux controller is not a syscon device.
-
-&i2c0 {
-	fpga@66 { // fpga connected to i2c
-		compatible = "fsl,lx2160aqds-fpga", "fsl,fpga-qixis-i2c",
-			     "simple-mfd";
-		reg = <0x66>;
-
-		mux: mux-controller {
-			compatible = "reg-mux";
-			#mux-control-cells = <1>;
-			mux-reg-masks = <0x54 0xf8>, /* 0: reg 0x54, bits 7:3 */
-					<0x54 0x07>; /* 1: reg 0x54, bits 2:0 */
-		};
-	};
-};
-
-mdio-mux-1 {
-	compatible = "mdio-mux-multiplexer";
-	mux-controls = <&mux 0>;
-	mdio-parent-bus = <&emdio1>;
-	#address-cells = <1>;
-	#size-cells = <0>;
-
-	mdio@0 {
-		reg = <0x0>;
-		#address-cells = <1>;
-		#size-cells = <0>;
-	};
-
-	mdio@8 {
-		reg = <0x8>;
-		#address-cells = <1>;
-		#size-cells = <0>;
-	};
-
-	..
-	..
-};
-
-mdio-mux-2 {
-	compatible = "mdio-mux-multiplexer";
-	mux-controls = <&mux 1>;
-	mdio-parent-bus = <&emdio2>;
-	#address-cells = <1>;
-	#size-cells = <0>;
-
-	mdio@0 {
-		reg = <0x0>;
-		#address-cells = <1>;
-		#size-cells = <0>;
-	};
-
-	mdio@1 {
-		reg = <0x1>;
-		#address-cells = <1>;
-		#size-cells = <0>;
-	};
-
-	..
-	..
-};
-
-Example 2:
-The parent device of mux controller is syscon device.
-
-syscon {
-	compatible = "syscon";
-
-	mux: mux-controller {
-		compatible = "mmio-mux";
-		#mux-control-cells = <1>;
-
-		mux-reg-masks = <0x3 0x30>, /* 0: reg 0x3, bits 5:4 */
-				<0x3 0x40>, /* 1: reg 0x3, bit 6 */
-		idle-states = <MUX_IDLE_AS_IS>, <0>;
-	};
-};
-
-video-mux {
-	compatible = "video-mux";
-	mux-controls = <&mux 0>;
-	#address-cells = <1>;
-	#size-cells = <0>;
-
-	ports {
-		/* inputs 0..3 */
-		port@0 {
-			reg = <0>;
-		};
-		port@1 {
-			reg = <1>;
-		};
-		port@2 {
-			reg = <2>;
-		};
-		port@3 {
-			reg = <3>;
-		};
-
-		/* output */
-		port@4 {
-			reg = <4>;
-		};
-	};
-};
diff --git a/Documentation/devicetree/bindings/mux/reg-mux.yaml b/Documentation/devicetree/bindings/mux/reg-mux.yaml
new file mode 100644
index 000000000000..60d5746eb39d
--- /dev/null
+++ b/Documentation/devicetree/bindings/mux/reg-mux.yaml
@@ -0,0 +1,143 @@
+# SPDX-License-Identifier: GPL-2.0
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/mux/reg-mux.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Generic register bitfield-based multiplexer controller bindings
+
+maintainers:
+  - Peter Rosin <peda@axentia.se>
+
+description: |+
+  Define register bitfields to be used to control multiplexers. The parent
+  device tree node must be a device node to provide register r/w access.
+
+properties:
+  compatible:
+    enum:
+      - reg-mux   # parent device of mux controller is not syscon device
+      - mmio-mux  # parent device of mux controller is syscon device
+
+  reg: true
+
+  '#mux-control-cells':
+    const: 1
+
+  mux-reg-masks:
+    description: an array of register offset and pre-shifted bitfield mask
+      pairs, each describing a single mux control.
+
+  idle-states: true
+
+required:
+  - compatible
+  - mux-reg-masks
+  - '#mux-control-cells'
+
+additionalProperties: false
+
+examples:
+  - |
+    /* The parent device of mux controller is not a syscon device. */
+
+    #include <dt-bindings/mux/mux.h>
+
+    mux-controller {
+        compatible = "reg-mux";
+        #mux-control-cells = <1>;
+        mux-reg-masks =
+            <0x54 0xf8>, /* 0: reg 0x54, bits 7:3 */
+            <0x54 0x07>; /* 1: reg 0x54, bits 2:0 */
+    };
+
+    mdio-mux-1 {
+        compatible = "mdio-mux-multiplexer";
+        mux-controls = <&mux1 0>;
+        mdio-parent-bus = <&emdio1>;
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        mdio@0 {
+            reg = <0x0>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+        };
+
+        mdio@8 {
+            reg = <0x8>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+        };
+    };
+
+    mdio-mux-2 {
+        compatible = "mdio-mux-multiplexer";
+        mux-controls = <&mux1 1>;
+        mdio-parent-bus = <&emdio2>;
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        mdio@0 {
+            reg = <0x0>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+        };
+
+        mdio@1 {
+            reg = <0x1>;
+            #address-cells = <1>;
+            #size-cells = <0>;
+        };
+    };
+
+  - |
+    /* The parent device of mux controller is syscon device. */
+
+    #include <dt-bindings/mux/mux.h>
+    syscon@1000 {
+        compatible = "fsl,imx7d-iomuxc-gpr", "fsl,imx6q-iomuxc-gpr", "syscon", "simple-mfd";
+        reg = <0x1000 0x100>;
+
+        mux2: mux-controller {
+            compatible = "mmio-mux";
+            #mux-control-cells = <1>;
+
+            mux-reg-masks =
+                <0x3 0x30>, /* 0: reg 0x3, bits 5:4 */
+                <0x3 0x40>; /* 1: reg 0x3, bit 6 */
+            idle-states = <MUX_IDLE_AS_IS>, <0>;
+        };
+    };
+
+    video-mux {
+        compatible = "video-mux";
+        mux-controls = <&mux2 0>;
+        #address-cells = <1>;
+        #size-cells = <0>;
+
+        ports {
+            #address-cells = <1>;
+            #size-cells = <0>;
+
+            /* inputs 0..3 */
+            port@0 {
+                reg = <0>;
+            };
+            port@1 {
+                reg = <1>;
+            };
+            port@2 {
+                reg = <2>;
+            };
+            port@3 {
+                reg = <3>;
+            };
+
+            /* output */
+            port@4 {
+                reg = <4>;
+            };
+        };
+    };
+...