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#"
36   - Chris Packham <chris.packham@alliedtelesis.co.nz>
40     const: spi-mux
42   mux-controls:
46   - compatible
47   - reg
48   - spi-max-frequency
49   - mux-controls
54   - |
55     #include <dt-bindings/gpio/gpio.h>
56     mux: mux-controller {
57         compatible = "gpio-mux";
58         #mux-control-cells = <0>;
60         mux-gpios = <&gpio0 3 GPIO_ACTIVE_HIGH>;
63     spi {
64         #address-cells = <1>;
65         #size-cells = <0>;
66         spi@0 {
67             compatible = "spi-mux";
69             #address-cells = <1>;
70             #size-cells = <0>;
71             spi-max-frequency = <100000000>;
73             mux-controls = <&mux>;
75             spi-flash@0 {
76                 compatible = "jedec,spi-nor";
78                 #address-cells = <1>;
79                 #size-cells = <0>;
80                 spi-max-frequency = <40000000>;
83             spi-device@1 {
86                 #address-cells = <1>;
87                 #size-cells = <0>;
88                 spi-max-frequency = <10000000>;