| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame] | 1 | GPIO-based multiplexer controller bindings |
| 2 | |
| 3 | Define what GPIO pins are used to control a multiplexer. Or several |
| 4 | multiplexers, if the same pins control more than one multiplexer. |
| 5 | |
| 6 | Required properties: |
| 7 | - compatible : "gpio-mux" |
| 8 | - mux-gpios : list of gpios used to control the multiplexer, least |
| 9 | significant bit first. |
| 10 | - #mux-control-cells : <0> |
| 11 | * Standard mux-controller bindings as decribed in mux-controller.txt |
| 12 | |
| 13 | Optional properties: |
| 14 | - idle-state : if present, the state the mux will have when idle. The |
| 15 | special state MUX_IDLE_AS_IS is the default. |
| 16 | |
| 17 | The multiplexer state is defined as the number represented by the |
| 18 | multiplexer GPIO pins, where the first pin is the least significant |
| 19 | bit. An active pin is a binary 1, an inactive pin is a binary 0. |
| 20 | |
| 21 | Example: |
| 22 | |
| 23 | mux: mux-controller { |
| 24 | compatible = "gpio-mux"; |
| 25 | #mux-control-cells = <0>; |
| 26 | |
| 27 | mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>, |
| 28 | <&pioA 1 GPIO_ACTIVE_HIGH>; |
| 29 | }; |
| 30 | |
| 31 | adc-mux { |
| 32 | compatible = "io-channel-mux"; |
| 33 | io-channels = <&adc 0>; |
| 34 | io-channel-names = "parent"; |
| 35 | |
| 36 | mux-controls = <&mux>; |
| 37 | |
| 38 | channels = "sync-1", "in", "out", "sync-2"; |
| 39 | }; |
| 40 | |
| 41 | i2c-mux { |
| 42 | compatible = "i2c-mux"; |
| 43 | i2c-parent = <&i2c1>; |
| 44 | |
| 45 | mux-controls = <&mux>; |
| 46 | |
| 47 | #address-cells = <1>; |
| 48 | #size-cells = <0>; |
| 49 | |
| 50 | i2c@0 { |
| 51 | reg = <0>; |
| 52 | #address-cells = <1>; |
| 53 | #size-cells = <0>; |
| 54 | |
| 55 | ssd1307: oled@3c { |
| 56 | /* ... */ |
| 57 | }; |
| 58 | }; |
| 59 | |
| 60 | i2c@3 { |
| 61 | reg = <3>; |
| 62 | #address-cells = <1>; |
| 63 | #size-cells = <0>; |
| 64 | |
| 65 | pca9555: pca9555@20 { |
| 66 | /* ... */ |
| 67 | }; |
| 68 | }; |
| 69 | }; |