bindings/spi/spi-mux.yaml

1 # SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
3 ---
4 $id: http://devicetree.org/schemas/spi/spi-mux.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
7 title: Generic SPI Multiplexer
10   This binding describes a SPI bus multiplexer to route the SPI chip select
11   signals. This can be used when you need more devices than the SPI controller
13   setting of the multiplexer to a channel needs to be done by a specific SPI mux
16         MOSI /--------------------------------+--------+--------+--------\
17         MISO |/------------------------------+|-------+|-------+|-------\|
18          SCL ||/----------------------------+||------+||------+||------\||
20       +------------+                        |||      |||      |||      |||
21       | SoC  |||   |                      +-+++-+  +-+++-+  +-+++-+  +-+++-+
23       |   +--+++-+ | CS-X  +------+\      +--+--+  +--+--+  +--+--+  +--+--+
24       |   | SPI  +-|-------+ Mux  |\\   CS-0 |        |        |        |
25       |   +------+ |       +--+---+\\\-------/   CS-1 |        |        |
26       |            |          |    \\\----------------/   CS-2 |        |
27       |   +------+ |          |     \\-------------------------/   CS-3 |
28       |   | ?    +-|----------/      \----------------------------------/
29       |   +------+ |
30       +------------+
33   - $ref: /schemas/spi/spi-controller.yaml#
34   - $ref: /schemas/spi/spi-peripheral-props.yaml#
37   - Chris Packham <chris.packham@alliedtelesis.co.nz>
41     const: spi-mux
43   mux-controls:
47   - compatible
48   - reg
49   - spi-max-frequency
50   - mux-controls
55   - |
56     #include <dt-bindings/gpio/gpio.h>
57     mux: mux-controller {
58         compatible = "gpio-mux";
59         #mux-control-cells = <0>;
61         mux-gpios = <&gpio0 3 GPIO_ACTIVE_HIGH>;
64     spi {
65         #address-cells = <1>;
66         #size-cells = <0>;
67         spi@0 {
68             compatible = "spi-mux";
70             #address-cells = <1>;
71             #size-cells = <0>;
72             spi-max-frequency = <100000000>;
74             mux-controls = <&mux>;
77                 compatible = "jedec,spi-nor";
79                 spi-max-frequency = <40000000>;
85                 spi-max-frequency = <10000000>;