bindings/i2c/i2c-mux-gpio.yaml

1 # SPDX-License-Identifier: GPL-2.0-only
3 ---
4 $id: http://devicetree.org/schemas/i2c/i2c-mux-gpio.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
7 title: GPIO-based I2C Bus Mux
10   - Wolfram Sang <wsa@kernel.org>
15                                   +-----+  +-----+
17     +------------+                +-----+  +-----+
19     |            |          /--------+--------+
20     |   +------+ |  +------+    child bus A, on GPIO value set to 0
21     |   | I2C  |-|--| Mux  |
22     |   +------+ |  +--+---+    child bus B, on GPIO value set to 1
23     |            |     |    \----------+--------+--------+
24     |   +------+ |     |               |        |        |
25     |   | GPIO |-|-----+            +-----+  +-----+  +-----+
26     |   +------+ |                  | dev |  | dev |  | dev |
27     +------------+                  +-----+  +-----+  +-----+
33   property will be output using the list of GPIOs, the first in the list holding the least-
36   If an idle state is defined, using the idle-state (optional) property, whenever an access is not
37   being made to a device on a child bus, the GPIOs will be set according to the idle value.
39   If an idle state is not defined, the most recently used value will be left programmed into
44     const: i2c-mux-gpio
46   i2c-parent:
47     description: phandle of the I2C bus that this multiplexer's master-side port is connected to
50   mux-gpios:
55   idle-state:
56     description: Value to set the muxer to when idle. When no value is given, it defaults to the
60   settle-time-us:
61     description: Delay to wait before doing any transfer when a new bus gets selected.
64   - $ref: i2c-mux.yaml
69   - compatible
70   - i2c-parent
71   - mux-gpios
74   - |
76       compatible = "i2c-mux-gpio";
77       #address-cells = <1>;
78       #size-cells = <0>;
79       mux-gpios = <&gpio1 22 0>, <&gpio1 23 0>;
80       i2c-parent = <&i2c1>;
84         #address-cells = <1>;
85         #size-cells = <0>;
88           compatible = "solomon,ssd1307fb-i2c";
91           reset-gpios = <&gpio2 7 1>;
97         #address-cells = <1>;
98         #size-cells = <0>;
102           gpio-controller;
103           #gpio-cells = <2>;