summaryrefslogtreecommitdiffstats
path: root/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.yaml
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.yaml
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.yaml')
-rw-r--r--Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.yaml103
1 files changed, 103 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.yaml b/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.yaml
new file mode 100644
index 0000000000..2e3d555eb9
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/i2c-mux-pinctrl.yaml
@@ -0,0 +1,103 @@
+# SPDX-License-Identifier: GPL-2.0-only
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i2c/i2c-mux-pinctrl.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Pinctrl-based I2C Bus Mux
+
+maintainers:
+ - Wolfram Sang <wsa@kernel.org>
+
+description: |
+ This binding describes an I2C bus multiplexer that uses pin multiplexing to route the I2C
+ signals, and represents the pin multiplexing configuration using the pinctrl device tree
+ bindings.
+
+ +-----+ +-----+
+ | dev | | dev |
+ +------------------------+ +-----+ +-----+
+ | SoC | | |
+ | /----|------+--------+
+ | +---+ +------+ | child bus A, on first set of pins
+ | |I2C|---|Pinmux| |
+ | +---+ +------+ | child bus B, on second set of pins
+ | \----|------+--------+--------+
+ | | | | |
+ +------------------------+ +-----+ +-----+ +-----+
+ | dev | | dev | | dev |
+ +-----+ +-----+ +-----+
+
+ For each named state defined in the pinctrl-names property, an I2C child bus will be created.
+ I2C child bus numbers are assigned based on the index into the pinctrl-names property.
+
+ The only exception is that no bus will be created for a state named "idle". If such a state is
+ defined, it must be the last entry in pinctrl-names. For example:
+
+ pinctrl-names = "ddc", "pta", "idle" -> ddc = bus 0, pta = bus 1
+ pinctrl-names = "ddc", "idle", "pta" -> Invalid ("idle" not last)
+ pinctrl-names = "idle", "ddc", "pta" -> Invalid ("idle" not last)
+
+ Whenever an access is made to a device on a child bus, the relevant pinctrl state will be
+ programmed into hardware.
+
+ If an idle state is defined, whenever an access is not being made to a device on a child bus,
+ the idle pinctrl state will be programmed into hardware.
+
+ If an idle state is not defined, the most recently used pinctrl state will be left programmed
+ into hardware whenever no access is being made of a device on a child bus.
+
+properties:
+ compatible:
+ const: i2c-mux-pinctrl
+
+ i2c-parent:
+ $ref: /schemas/types.yaml#/definitions/phandle
+ description: The phandle of the I2C bus that this multiplexer's master-side port is connected
+ to.
+
+allOf:
+ - $ref: i2c-mux.yaml
+
+unevaluatedProperties: false
+
+required:
+ - compatible
+ - i2c-parent
+
+examples:
+ - |
+ i2cmux {
+ compatible = "i2c-mux-pinctrl";
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ i2c-parent = <&i2c1>;
+
+ pinctrl-names = "ddc", "pta", "idle";
+ pinctrl-0 = <&state_i2cmux_ddc>;
+ pinctrl-1 = <&state_i2cmux_pta>;
+ pinctrl-2 = <&state_i2cmux_idle>;
+
+ i2c@0 {
+ reg = <0>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ eeprom@50 {
+ compatible = "atmel,24c02";
+ reg = <0x50>;
+ };
+ };
+
+ i2c@1 {
+ reg = <1>;
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ eeprom@50 {
+ compatible = "atmel,24c02";
+ reg = <0x50>;
+ };
+ };
+ };