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1# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)2%YAML 1.23---4$id: http://devicetree.org/schemas/spi/spi-mux.yaml#5$schema: http://devicetree.org/meta-schemas/core.yaml#6 7title: Generic SPI Multiplexer8 9description: |10 This binding describes a SPI bus multiplexer to route the SPI chip select11 signals. This can be used when you need more devices than the SPI controller12 has chip selects available. An example setup is shown in ASCII art; the actual13 setting of the multiplexer to a channel needs to be done by a specific SPI mux14 driver.15 16 MOSI /--------------------------------+--------+--------+--------\17 MISO |/------------------------------+|-------+|-------+|-------\|18 SCL ||/----------------------------+||------+||------+||------\||19 ||| ||| ||| ||| |||20 +------------+ ||| ||| ||| |||21 | SoC ||| | +-+++-+ +-+++-+ +-+++-+ +-+++-+22 | ||| | | dev | | dev | | dev | | dev |23 | +--+++-+ | CS-X +------+\ +--+--+ +--+--+ +--+--+ +--+--+24 | | SPI +-|-------+ Mux |\\ CS-0 | | | |25 | +------+ | +--+---+\\\-------/ CS-1 | | |26 | | | \\\----------------/ CS-2 | |27 | +------+ | | \\-------------------------/ CS-3 |28 | | ? +-|----------/ \----------------------------------/29 | +------+ |30 +------------+31 32allOf:33 - $ref: /schemas/spi/spi-controller.yaml#34 - $ref: /schemas/spi/spi-peripheral-props.yaml#35 36maintainers:37 - Chris Packham <chris.packham@alliedtelesis.co.nz>38 39properties:40 compatible:41 const: spi-mux42 43 mux-controls:44 maxItems: 145 46required:47 - compatible48 - reg49 - spi-max-frequency50 - mux-controls51 52unevaluatedProperties: false53 54examples:55 - |56 #include <dt-bindings/gpio/gpio.h>57 mux: mux-controller {58 compatible = "gpio-mux";59 #mux-control-cells = <0>;60 61 mux-gpios = <&gpio0 3 GPIO_ACTIVE_HIGH>;62 };63 64 spi {65 #address-cells = <1>;66 #size-cells = <0>;67 spi@0 {68 compatible = "spi-mux";69 reg = <0>;70 #address-cells = <1>;71 #size-cells = <0>;72 spi-max-frequency = <100000000>;73 74 mux-controls = <&mux>;75 76 flash@0 {77 compatible = "jedec,spi-nor";78 reg = <0>;79 spi-max-frequency = <40000000>;80 };81 82 sensor@1 {83 compatible = "bosch,bme680";84 reg = <1>;85 spi-max-frequency = <10000000>;86 };87 };88 };89