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| 1 | +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) |
| 2 | +%YAML 1.2 |
| 3 | +--- |
| 4 | +$id: http://devicetree.org/schemas/i2c/i2c-demux-pinctrl.yaml# |
| 5 | +$schema: http://devicetree.org/meta-schemas/core.yaml# |
| 6 | + |
| 7 | +title: Pinctrl-based I2C Bus Demultiplexer |
| 8 | + |
| 9 | +maintainers: |
| 10 | + - Wolfram Sang <[email protected]> |
| 11 | + |
| 12 | +description: | |
| 13 | + This binding describes an I2C bus demultiplexer that uses pin multiplexing to |
| 14 | + route the I2C signals, and represents the pin multiplexing configuration |
| 15 | + using the pinctrl device tree bindings. This may be used to select one I2C |
| 16 | + IP core at runtime which may have a better feature set for a given task than |
| 17 | + another I2C IP core on the SoC. The most simple example is to fall back to |
| 18 | + GPIO bitbanging if your current runtime configuration hits an errata of the |
| 19 | + internal IP core. |
| 20 | +
|
| 21 | + +-------------------------------+ |
| 22 | + | SoC | |
| 23 | + | | +-----+ +-----+ |
| 24 | + | +------------+ | | dev | | dev | |
| 25 | + | |I2C IP Core1|--\ | +-----+ +-----+ |
| 26 | + | +------------+ \-------+ | | | |
| 27 | + | |Pinctrl|--|------+--------+ |
| 28 | + | +------------+ +-------+ | |
| 29 | + | |I2C IP Core2|--/ | |
| 30 | + | +------------+ | |
| 31 | + | | |
| 32 | + +-------------------------------+ |
| 33 | +
|
| 34 | +allOf: |
| 35 | + - $ref: i2c-mux.yaml |
| 36 | + - $ref: /schemas/i2c/i2c-controller.yaml# |
| 37 | + |
| 38 | +properties: |
| 39 | + compatible: |
| 40 | + const: i2c-demux-pinctrl |
| 41 | + |
| 42 | + i2c-parent: |
| 43 | + $ref: /schemas/types.yaml#/definitions/phandle-array |
| 44 | + description: |
| 45 | + List of phandles of I2C masters available for selection. The first one |
| 46 | + will be used as default. |
| 47 | + |
| 48 | + i2c-bus-name: |
| 49 | + $ref: /schemas/types.yaml#/definitions/string |
| 50 | + description: |
| 51 | + The name of this bus. Also needed as pinctrl-name for the I2C parents. |
| 52 | + |
| 53 | +required: |
| 54 | + - compatible |
| 55 | + - i2c-parent |
| 56 | + - i2c-bus-name |
| 57 | + |
| 58 | +unevaluatedProperties: false |
| 59 | + |
| 60 | +examples: |
| 61 | + - | |
| 62 | + #include <dt-bindings/gpio/gpio.h> |
| 63 | + #include <dt-bindings/interrupt-controller/irq.h> |
| 64 | +
|
| 65 | + gpioi2c2: i2c-9 { |
| 66 | + #address-cells = <1>; |
| 67 | + #size-cells = <0>; |
| 68 | + compatible = "i2c-gpio"; |
| 69 | + scl-gpios = <&gpio5 5 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>; |
| 70 | + sda-gpios = <&gpio5 6 (GPIO_ACTIVE_HIGH | GPIO_OPEN_DRAIN)>; |
| 71 | + i2c-gpio,delay-us = <5>; |
| 72 | +
|
| 73 | + // The I2C controller must have its status "disabled". The I2C bus |
| 74 | + // demultiplexer will enable it at runtime when needed. |
| 75 | + status = "disabled"; |
| 76 | + }; |
| 77 | +
|
| 78 | + iic2: i2c@e6520000 { |
| 79 | + reg = <0xe6520000 0x425>; |
| 80 | + pinctrl-0 = <&iic2_pins>; |
| 81 | + // The pinctrl property for the parent I2C controller needs a pinctrl |
| 82 | + // state with the same name as i2c-bus-name in the I2C bus demultiplexer |
| 83 | + // node, not "default"! |
| 84 | + pinctrl-names = "i2c-hdmi"; |
| 85 | +
|
| 86 | + clock-frequency = <100000>; |
| 87 | +
|
| 88 | + // The I2C controller must have its status "disabled". The I2C bus |
| 89 | + // demultiplexer will enable it at runtime when needed. |
| 90 | + status = "disabled"; |
| 91 | + }; |
| 92 | +
|
| 93 | + i2c2: i2c@e6530000 { |
| 94 | + reg = <0 0xe6530000 0 0x40>; |
| 95 | + pinctrl-0 = <&i2c2_pins>; |
| 96 | + // The pinctrl property for the parent I2C controller needs a pinctrl |
| 97 | + // state with the same name as i2c-bus-name in the I2C bus demultiplexer |
| 98 | + // node, not "default"! |
| 99 | + pinctrl-names = "i2c-hdmi"; |
| 100 | +
|
| 101 | + clock-frequency = <100000>; |
| 102 | +
|
| 103 | + // The I2C controller must have its status "disabled". The I2C bus |
| 104 | + // demultiplexer will enable it at runtime when needed. |
| 105 | + status = "disabled"; |
| 106 | + }; |
| 107 | +
|
| 108 | + // Example for a bus to be demuxed. It contains various I2C clients for |
| 109 | + // HDMI, so the bus is named "i2c-hdmi": |
| 110 | + i2chdmi: i2c-mux3 { |
| 111 | + compatible = "i2c-demux-pinctrl"; |
| 112 | + i2c-parent = <&iic2>, <&i2c2>, <&gpioi2c2>; |
| 113 | + i2c-bus-name = "i2c-hdmi"; |
| 114 | + #address-cells = <1>; |
| 115 | + #size-cells = <0>; |
| 116 | +
|
| 117 | + ak4643: codec@12 { |
| 118 | + compatible = "asahi-kasei,ak4643"; |
| 119 | + #sound-dai-cells = <0>; |
| 120 | + reg = <0x12>; |
| 121 | + }; |
| 122 | +
|
| 123 | + composite-in@20 { |
| 124 | + compatible = "adi,adv7180"; |
| 125 | + reg = <0x20>; |
| 126 | +
|
| 127 | + port { |
| 128 | + adv7180: endpoint { |
| 129 | + bus-width = <8>; |
| 130 | + remote-endpoint = <&vin1ep0>; |
| 131 | + }; |
| 132 | + }; |
| 133 | + }; |
| 134 | +
|
| 135 | + hdmi@39 { |
| 136 | + compatible = "adi,adv7511w"; |
| 137 | + reg = <0x39>; |
| 138 | + interrupt-parent = <&gpio1>; |
| 139 | + interrupts = <15 IRQ_TYPE_LEVEL_LOW>; |
| 140 | + clocks = <&cec_clock>; |
| 141 | + clock-names = "cec"; |
| 142 | +
|
| 143 | + avdd-supply = <&fixedregulator1v8>; |
| 144 | + dvdd-supply = <&fixedregulator1v8>; |
| 145 | + pvdd-supply = <&fixedregulator1v8>; |
| 146 | + dvdd-3v-supply = <&fixedregulator3v3>; |
| 147 | + bgvdd-supply = <&fixedregulator1v8>; |
| 148 | +
|
| 149 | + adi,input-depth = <8>; |
| 150 | + adi,input-colorspace = "rgb"; |
| 151 | + adi,input-clock = "1x"; |
| 152 | +
|
| 153 | + ports { |
| 154 | + #address-cells = <1>; |
| 155 | + #size-cells = <0>; |
| 156 | +
|
| 157 | + port@0 { |
| 158 | + reg = <0>; |
| 159 | + adv7511_in: endpoint { |
| 160 | + remote-endpoint = <&lvds0_out>; |
| 161 | + }; |
| 162 | + }; |
| 163 | +
|
| 164 | + port@1 { |
| 165 | + reg = <1>; |
| 166 | + adv7511_out: endpoint { |
| 167 | + remote-endpoint = <&hdmi_con_out>; |
| 168 | + }; |
| 169 | + }; |
| 170 | + }; |
| 171 | + }; |
| 172 | + }; |
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