Signed-off-by: Peter Rosin <p...@axentia.se>
---
.../devicetree/bindings/misc/mux-controller.txt | 106 +++++++++++++++++++++
.../devicetree/bindings/misc/mux-gpio.txt | 78 +++++++++++++++
MAINTAINERS | 5 +
3 files changed, 189 insertions(+)
create mode 100644 Documentation/devicetree/bindings/misc/mux-controller.txt
create mode 100644 Documentation/devicetree/bindings/misc/mux-gpio.txt
diff --git a/Documentation/devicetree/bindings/misc/mux-controller.txt
b/Documentation/devicetree/bindings/misc/mux-controller.txt
new file mode 100644
index 000000000000..8e0733f60a37
--- /dev/null
+++ b/Documentation/devicetree/bindings/misc/mux-controller.txt
@@ -0,0 +1,106 @@
+Common multiplexer controller bindings
+
+A mux controller will have one, or several, consumer devices that uses the
+mux controller. Thus, a mux controller can possibly control several
+parallel multiplexers. If there are several consumer devices, the node for
+a mux controller will have one child node for each consumer of the multiplexer
+controller. If there is only one consumer of the mux controller, the mux
+controller node can be the child (with node name 'mux-controller') of the
+consumer node.
+
+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.
+
+Example:
+
+ /*
+ * One consumer of a 2-way multiplexer controller by one GPIO-line,
+ * with the multiplexer controller as a child node.
+ */
+ adc-mux {
+ compatible = "iio-mux";
+ io-channels = <&adc 0>;
+ io-channel-names = "parent";
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ mux-controller {
+ compatible = "mux-gpio";
+
+ mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>;
+ };
+
+ sync-1@0 {
+ reg = <0>;
+ };
+
+ in@1 {
+ reg = <1>;
+ };
+ };
+
+ /*
+ * 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 {
+ compatible = "mux-gpio";
+
+ mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+ <&pioA 1 GPIO_ACTIVE_HIGH>;
+
+ adc-mux {
+ compatible = "iio-mux";
+ io-channels = <&adc 0>;
+ io-channel-names = "parent";
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ sync-1@0 {
+ reg = <0>;
+ };
+
+ in@1 {
+ reg = <1>;
+ };
+
+ out@2 {
+ reg = <2>;
+ };
+
+ sync-2@3 {
+ reg = <3>;
+ };
+ };
+
+ i2c-mux {
+ compatible = "i2c-mux-simple,mux-locked";
+ i2c-parent = <&i2c1>;
+
+ #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/misc/mux-gpio.txt
b/Documentation/devicetree/bindings/misc/mux-gpio.txt
new file mode 100644
index 000000000000..23b87913f4b3
--- /dev/null
+++ b/Documentation/devicetree/bindings/misc/mux-gpio.txt
@@ -0,0 +1,78 @@
+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 : "mux-gpio"
+- mux-gpios : list of gpios used to control the multiplexer, least
+ significant bit first.
+* 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 multiplexer state is defined as the number represented by the
+multiplexer GPIO pins, where the first pin is the least significant
+bit. And active pin is a binary 1, an inactive pin is a binary 0.
+
+Example:
+ mux {
+ compatible = "mux-gpio";
+
+ mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
+ <&pioA 1 GPIO_ACTIVE_HIGH>;
+
+ adc {
+ compatible = "iio-mux";
+ io-channels = <&adc 0>;
+ io-channel-names = "parent";
+
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ sync-1@0 {
+ reg = <0>;
+ };
+
+ in@1 {
+ reg = <1>;
+ };
+
+ out@2 {
+ reg = <2>;
+ };
+
+ sync-2@3 {
+ reg = <3>;
+ };
+ };
+
+ i2c-mux {
+ compatible = "i2c-mux-simple,mux-locked";
+ i2c-parent = <&i2c1>;
+
+ #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/MAINTAINERS b/MAINTAINERS
index 4ebcd8df29d2..35869ed0a50e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8402,6 +8402,11 @@ S: Orphan
F: drivers/mmc/host/mmc_spi.c
F: include/linux/spi/mmc_spi.h
+MULTIPLEXER SUBSYSTEM
+M: Peter Rosin <p...@axentia.se>
+S: Maintained
+F: Documentation/devicetree/bindings/misc/mux-*
+
MULTISOUND SOUND DRIVER
M: Andrew Veliath <andre...@usa.net>
S: Maintained
--
2.1.4
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