| Tom Rini | 53633a8 | 2024-02-29 12:33:36 -0500 | [diff] [blame] | 1 | # SPDX-License-Identifier: GPL-2.0 |
| 2 | %YAML 1.2 |
| 3 | --- |
| 4 | $id: http://devicetree.org/schemas/i2c/i2c-mux.yaml# |
| 5 | $schema: http://devicetree.org/meta-schemas/core.yaml# |
| 6 | |
| 7 | title: Common i2c bus multiplexer/switch properties. |
| 8 | |
| 9 | maintainers: |
| 10 | - Peter Rosin <peda@axentia.se> |
| 11 | |
| 12 | description: |+ |
| 13 | An i2c bus multiplexer/switch will have several child busses that are numbered |
| 14 | uniquely in a device dependent manner. The nodes for an i2c bus |
| 15 | multiplexer/switch will have one child node for each child bus. |
| 16 | |
| 17 | For i2c multiplexers/switches that have child nodes that are a mixture of both |
| 18 | i2c child busses and other child nodes, the 'i2c-mux' subnode can be used for |
| 19 | populating the i2c child busses. If an 'i2c-mux' subnode is present, only |
| 20 | subnodes of this will be considered as i2c child busses. |
| 21 | |
| 22 | properties: |
| 23 | $nodename: |
| 24 | pattern: '^(i2c-?)?mux' |
| 25 | |
| 26 | '#address-cells': |
| 27 | const: 1 |
| 28 | |
| 29 | '#size-cells': |
| 30 | const: 0 |
| 31 | |
| 32 | patternProperties: |
| 33 | '^i2c@[0-9a-f]+$': |
| 34 | $ref: /schemas/i2c/i2c-controller.yaml |
| 35 | unevaluatedProperties: false |
| 36 | |
| 37 | properties: |
| 38 | reg: |
| 39 | description: The mux selector sub-bus number for the child I2C bus. |
| 40 | maxItems: 1 |
| 41 | |
| 42 | additionalProperties: true |
| 43 | |
| 44 | examples: |
| 45 | - | |
| 46 | /* |
| 47 | * An NXP pca9548 8 channel I2C multiplexer at address 0x70 |
| 48 | * with two NXP pca8574 GPIO expanders attached, one each to |
| 49 | * ports 3 and 4. |
| 50 | */ |
| 51 | i2c { |
| 52 | #address-cells = <1>; |
| 53 | #size-cells = <0>; |
| 54 | |
| 55 | i2c-mux@70 { |
| 56 | compatible = "nxp,pca9548"; |
| 57 | reg = <0x70>; |
| 58 | #address-cells = <1>; |
| 59 | #size-cells = <0>; |
| 60 | |
| 61 | i2c@3 { |
| 62 | #address-cells = <1>; |
| 63 | #size-cells = <0>; |
| 64 | reg = <3>; |
| 65 | |
| 66 | gpio@20 { |
| 67 | compatible = "nxp,pca9555"; |
| 68 | gpio-controller; |
| 69 | #gpio-cells = <2>; |
| 70 | reg = <0x20>; |
| 71 | }; |
| 72 | }; |
| 73 | i2c@4 { |
| 74 | #address-cells = <1>; |
| 75 | #size-cells = <0>; |
| 76 | reg = <4>; |
| 77 | |
| 78 | gpio@20 { |
| 79 | compatible = "nxp,pca9555"; |
| 80 | gpio-controller; |
| 81 | #gpio-cells = <2>; |
| 82 | reg = <0x20>; |
| 83 | }; |
| 84 | }; |
| 85 | }; |
| 86 | }; |
| 87 | ... |