1 # SPDX-License-Identifier: (GPL-2.0 OR BSD-2-C 1 # SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
2 %YAML 1.2 2 %YAML 1.2
3 --- 3 ---
4 $id: http://devicetree.org/schemas/spi/spi-mux 4 $id: http://devicetree.org/schemas/spi/spi-mux.yaml#
5 $schema: http://devicetree.org/meta-schemas/co 5 $schema: http://devicetree.org/meta-schemas/core.yaml#
6 6
7 title: Generic SPI Multiplexer 7 title: Generic SPI Multiplexer
8 8
9 description: | 9 description: |
10 This binding describes a SPI bus 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 11 signals. This can be used when you need more devices than the SPI controller
12 has chip selects available. An example setup 12 has chip selects available. An example setup is shown in ASCII art; the actual
13 setting of the multiplexer to a channel need 13 setting of the multiplexer to a channel needs to be done by a specific SPI mux
14 driver. 14 driver.
15 15
16 MOSI /-------------------------------- 16 MOSI /--------------------------------+--------+--------+--------\
17 MISO |/------------------------------+ 17 MISO |/------------------------------+|-------+|-------+|-------\|
18 SCL ||/----------------------------+| 18 SCL ||/----------------------------+||------+||------+||------\||
19 ||| || 19 ||| ||| ||| ||| |||
20 +------------+ || 20 +------------+ ||| ||| ||| |||
21 | SoC ||| | +-++ 21 | SoC ||| | +-+++-+ +-+++-+ +-+++-+ +-+++-+
22 | ||| | | de 22 | ||| | | dev | | dev | | dev | | dev |
23 | +--+++-+ | CS-X +------+\ +--+ 23 | +--+++-+ | CS-X +------+\ +--+--+ +--+--+ +--+--+ +--+--+
24 | | SPI +-|-------+ Mux |\\ CS-0 | 24 | | SPI +-|-------+ Mux |\\ CS-0 | | | |
25 | +------+ | +--+---+\\\-------/ 25 | +------+ | +--+---+\\\-------/ CS-1 | | |
26 | | | \\\-------- 26 | | | \\\----------------/ CS-2 | |
27 | +------+ | | \\-------- 27 | +------+ | | \\-------------------------/ CS-3 |
28 | | ? +-|----------/ \-------- 28 | | ? +-|----------/ \----------------------------------/
29 | +------+ | 29 | +------+ |
30 +------------+ 30 +------------+
31 31
32 allOf: 32 allOf:
33 - $ref: /schemas/spi/spi-controller.yaml# 33 - $ref: /schemas/spi/spi-controller.yaml#
34 - $ref: /schemas/spi/spi-peripheral-props.ya 34 - $ref: /schemas/spi/spi-peripheral-props.yaml#
35 35
36 maintainers: 36 maintainers:
37 - Chris Packham <chris.packham@alliedtelesis. 37 - Chris Packham <chris.packham@alliedtelesis.co.nz>
38 38
39 properties: 39 properties:
40 compatible: 40 compatible:
41 const: spi-mux 41 const: spi-mux
42 42
43 mux-controls: 43 mux-controls:
44 maxItems: 1 44 maxItems: 1
45 45
46 required: 46 required:
47 - compatible 47 - compatible
48 - reg 48 - reg
49 - spi-max-frequency 49 - spi-max-frequency
50 - mux-controls 50 - mux-controls
51 51
52 unevaluatedProperties: false 52 unevaluatedProperties: false
53 53
54 examples: 54 examples:
55 - | 55 - |
56 #include <dt-bindings/gpio/gpio.h> 56 #include <dt-bindings/gpio/gpio.h>
57 mux: mux-controller { 57 mux: mux-controller {
58 compatible = "gpio-mux"; 58 compatible = "gpio-mux";
59 #mux-control-cells = <0>; 59 #mux-control-cells = <0>;
60 60
61 mux-gpios = <&gpio0 3 GPIO_ACTIVE_HIGH 61 mux-gpios = <&gpio0 3 GPIO_ACTIVE_HIGH>;
62 }; 62 };
63 63
64 spi { 64 spi {
65 #address-cells = <1>; 65 #address-cells = <1>;
66 #size-cells = <0>; 66 #size-cells = <0>;
67 spi@0 { 67 spi@0 {
68 compatible = "spi-mux"; 68 compatible = "spi-mux";
69 reg = <0>; 69 reg = <0>;
70 #address-cells = <1>; 70 #address-cells = <1>;
71 #size-cells = <0>; 71 #size-cells = <0>;
72 spi-max-frequency = <100000000>; 72 spi-max-frequency = <100000000>;
73 73
74 mux-controls = <&mux>; 74 mux-controls = <&mux>;
75 75
76 flash@0 { 76 flash@0 {
77 compatible = "jedec,spi-nor"; 77 compatible = "jedec,spi-nor";
78 reg = <0>; 78 reg = <0>;
79 spi-max-frequency = <40000000> 79 spi-max-frequency = <40000000>;
80 }; 80 };
81 81
82 sensor@1 { 82 sensor@1 {
83 compatible = "bosch,bme680"; 83 compatible = "bosch,bme680";
84 reg = <1>; 84 reg = <1>;
85 spi-max-frequency = <10000000> 85 spi-max-frequency = <10000000>;
86 }; 86 };
87 }; 87 };
88 }; 88 };
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