1 # SPDX-License-Identifier: GPL-2.0 1 # SPDX-License-Identifier: GPL-2.0
2 %YAML 1.2 2 %YAML 1.2
3 --- 3 ---
4 $id: http://devicetree.org/schemas/mux/mux-con 4 $id: http://devicetree.org/schemas/mux/mux-controller.yaml#
5 $schema: http://devicetree.org/meta-schemas/co 5 $schema: http://devicetree.org/meta-schemas/core.yaml#
6 6
7 title: Common multiplexer controller provider 7 title: Common multiplexer controller provider
8 8
9 maintainers: 9 maintainers:
10 - Peter Rosin <peda@axentia.se> 10 - Peter Rosin <peda@axentia.se>
11 11
12 description: | 12 description: |
13 A multiplexer (or mux) controller will have 13 A multiplexer (or mux) controller will have one, or several, consumer devices
14 that uses the mux controller. Thus, a mux co 14 that uses the mux controller. Thus, a mux controller can possibly control
15 several parallel multiplexers. Presumably th 15 several parallel multiplexers. Presumably there will be at least one
16 multiplexer needed by each consumer, but a s 16 multiplexer needed by each consumer, but a single mux controller can of course
17 control several multiplexers for a single co 17 control several multiplexers for a single consumer.
18 18
19 A mux controller provides a number of states 19 A mux controller provides a number of states to its consumers, and the state
20 space is a simple zero-based enumeration. I. 20 space is a simple zero-based enumeration. I.e. 0-1 for a 2-way multiplexer,
21 0-7 for an 8-way multiplexer, etc. 21 0-7 for an 8-way multiplexer, etc.
22 22
23 23
24 Mux controller nodes 24 Mux controller nodes
25 -------------------- 25 --------------------
26 26
27 Mux controller nodes must specify the number 27 Mux controller nodes must specify the number of cells used for the
28 specifier using the '#mux-control-cells' or 28 specifier using the '#mux-control-cells' or '#mux-state-cells' property.
29 The value of '#mux-state-cells' will always 29 The value of '#mux-state-cells' will always be one greater than the value
30 of '#mux-control-cells'. 30 of '#mux-control-cells'.
31 31
32 Optionally, mux controller nodes can also sp 32 Optionally, mux controller nodes can also specify the state the mux should
33 have when it is idle. The idle-state propert 33 have when it is idle. The idle-state property is used for this. If the
34 idle-state is not present, the mux controlle 34 idle-state is not present, the mux controller is typically left as is when
35 it is idle. For multiplexer chips that expos 35 it is idle. For multiplexer chips that expose several mux controllers, the
36 idle-state property is an array with one idl 36 idle-state property is an array with one idle state for each mux controller.
37 37
38 The special value (-1) may be used to indica 38 The special value (-1) may be used to indicate that the mux should be left
39 as is when it is idle. This is the default, 39 as is when it is idle. This is the default, but can still be useful for
40 mux controller chips with more than one mux 40 mux controller chips with more than one mux controller, particularly when
41 there is a need to "step past" a mux control 41 there is a need to "step past" a mux controller and set some other idle
42 state for a mux controller with a higher ind 42 state for a mux controller with a higher index.
43 43
44 Some mux controllers have the ability to dis 44 Some mux controllers have the ability to disconnect the input/output of the
45 multiplexer. Using this disconnected high-im 45 multiplexer. Using this disconnected high-impedance state as the idle state
46 is indicated with idle state (-2). 46 is indicated with idle state (-2).
47 47
48 These constants are available in 48 These constants are available in
49 49
50 #include <dt-bindings/mux/mux.h> 50 #include <dt-bindings/mux/mux.h>
51 51
52 as MUX_IDLE_AS_IS (-1) and MUX_IDLE_DISCONNE 52 as MUX_IDLE_AS_IS (-1) and MUX_IDLE_DISCONNECT (-2).
53 53
54 An example mux controller node look like thi 54 An example mux controller node look like this (the adg972a chip is a triple
55 4-way multiplexer): 55 4-way multiplexer):
56 56
57 mux: mux-controller@50 { 57 mux: mux-controller@50 {
58 compatible = "adi,adg792a"; 58 compatible = "adi,adg792a";
59 reg = <0x50>; 59 reg = <0x50>;
60 #mux-control-cells = <1>; 60 #mux-control-cells = <1>;
61 61
62 idle-state = <MUX_IDLE_DISCONNECT MUX_ID 62 idle-state = <MUX_IDLE_DISCONNECT MUX_IDLE_AS_IS 2>;
63 }; 63 };
64 64
65 select: 65 select:
66 anyOf: 66 anyOf:
67 - properties: 67 - properties:
68 $nodename: 68 $nodename:
69 pattern: '^mux-controller' 69 pattern: '^mux-controller'
70 - required: 70 - required:
71 - '#mux-control-cells' 71 - '#mux-control-cells'
72 - required: 72 - required:
73 - '#mux-state-cells' 73 - '#mux-state-cells'
74 74
75 properties: 75 properties:
76 $nodename: 76 $nodename:
77 pattern: '^mux-controller(@.*|-([0-9]|[1-9 77 pattern: '^mux-controller(@.*|-([0-9]|[1-9][0-9]+))?$'
78 78
79 '#mux-control-cells': 79 '#mux-control-cells':
80 enum: [ 0, 1 ] 80 enum: [ 0, 1 ]
81 81
82 '#mux-state-cells': 82 '#mux-state-cells':
83 enum: [ 1, 2 ] 83 enum: [ 1, 2 ]
84 84
85 idle-state: 85 idle-state:
86 $ref: /schemas/types.yaml#/definitions/int 86 $ref: /schemas/types.yaml#/definitions/int32
87 minimum: -2 87 minimum: -2
88 88
89 idle-states: 89 idle-states:
90 description: | 90 description: |
91 Mux controller nodes can specify the sta 91 Mux controller nodes can specify the state the mux should have when it is
92 idle. If the idle-state is not present, 92 idle. If the idle-state is not present, the mux controller is typically
93 left as is when it is idle. For multiple 93 left as is when it is idle. For multiplexer chips that expose several mux
94 controllers, the idle-state property is 94 controllers, the idle-state property is an array with one idle state for
95 each mux controller. 95 each mux controller.
96 96
97 The special value (-1) may be used to in 97 The special value (-1) may be used to indicate that the mux should be left
98 as is when it is idle. This is the defau 98 as is when it is idle. This is the default, but can still be useful for
99 mux controller chips with more than one 99 mux controller chips with more than one mux controller, particularly when
100 there is a need to "step past" a mux con 100 there is a need to "step past" a mux controller and set some other idle
101 state for a mux controller with a higher 101 state for a mux controller with a higher index.
102 102
103 Some mux controllers have the ability to 103 Some mux controllers have the ability to disconnect the input/output of the
104 multiplexer. Using this disconnected hig 104 multiplexer. Using this disconnected high-impedance state as the idle state
105 is indicated with idle state (-2). 105 is indicated with idle state (-2).
106 $ref: /schemas/types.yaml#/definitions/int 106 $ref: /schemas/types.yaml#/definitions/int32-array
107 items: 107 items:
108 minimum: -2 108 minimum: -2
109 109
110 additionalProperties: true 110 additionalProperties: true
111 111
112 examples: 112 examples:
113 - | 113 - |
114 #include <dt-bindings/gpio/gpio.h> 114 #include <dt-bindings/gpio/gpio.h>
115 115
116 /* One consumer of a 2-way mux controller 116 /* One consumer of a 2-way mux controller (one GPIO-line) */
117 mux: mux-controller { 117 mux: mux-controller {
118 compatible = "gpio-mux"; 118 compatible = "gpio-mux";
119 #mux-control-cells = <0>; 119 #mux-control-cells = <0>;
120 120
121 mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH> 121 mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>;
122 }; 122 };
123 123
124 adc-mux { 124 adc-mux {
125 compatible = "io-channel-mux"; 125 compatible = "io-channel-mux";
126 io-channels = <&adc 0>; 126 io-channels = <&adc 0>;
127 io-channel-names = "parent"; 127 io-channel-names = "parent";
128 128
129 mux-controls = <&mux>; 129 mux-controls = <&mux>;
130 mux-control-names = "adc"; 130 mux-control-names = "adc";
131 131
132 channels = "sync", "in"; 132 channels = "sync", "in";
133 }; 133 };
134 134
135 - | 135 - |
136 #include <dt-bindings/gpio/gpio.h> 136 #include <dt-bindings/gpio/gpio.h>
137 137
138 /* 138 /*
139 * Two consumers (one for an ADC line and 139 * Two consumers (one for an ADC line and one for an i2c bus) of
140 * parallel 4-way multiplexers controlled 140 * parallel 4-way multiplexers controlled by the same two GPIO-lines.
141 */ 141 */
142 mux2: mux-controller { 142 mux2: mux-controller {
143 compatible = "gpio-mux"; 143 compatible = "gpio-mux";
144 #mux-control-cells = <0>; 144 #mux-control-cells = <0>;
145 145
146 mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH> 146 mux-gpios = <&pioA 0 GPIO_ACTIVE_HIGH>,
147 <&pioA 1 GPIO_ACTIVE_HIGH>; 147 <&pioA 1 GPIO_ACTIVE_HIGH>;
148 }; 148 };
149 149
150 adc-mux { 150 adc-mux {
151 compatible = "io-channel-mux"; 151 compatible = "io-channel-mux";
152 io-channels = <&adc 0>; 152 io-channels = <&adc 0>;
153 io-channel-names = "parent"; 153 io-channel-names = "parent";
154 154
155 mux-controls = <&mux2>; 155 mux-controls = <&mux2>;
156 156
157 channels = "sync-1", "in", "out", "syn 157 channels = "sync-1", "in", "out", "sync-2";
158 }; 158 };
159 159
160 i2c-mux { 160 i2c-mux {
161 compatible = "i2c-mux"; 161 compatible = "i2c-mux";
162 i2c-parent = <&i2c1>; 162 i2c-parent = <&i2c1>;
163 163
164 mux-controls = <&mux2>; 164 mux-controls = <&mux2>;
165 165
166 #address-cells = <1>; 166 #address-cells = <1>;
167 #size-cells = <0>; 167 #size-cells = <0>;
168 168
169 i2c@0 { 169 i2c@0 {
170 reg = <0>; 170 reg = <0>;
171 #address-cells = <1>; 171 #address-cells = <1>;
172 #size-cells = <0>; 172 #size-cells = <0>;
173 173
174 ssd1307: oled@3c { 174 ssd1307: oled@3c {
175 reg = <0x3c>; 175 reg = <0x3c>;
176 }; 176 };
177 }; 177 };
178 178
179 i2c@3 { 179 i2c@3 {
180 reg = <3>; 180 reg = <3>;
181 #address-cells = <1>; 181 #address-cells = <1>;
182 #size-cells = <0>; 182 #size-cells = <0>;
183 183
184 pca9555: pca9555@20 { 184 pca9555: pca9555@20 {
185 reg = <0x20>; 185 reg = <0x20>;
186 }; 186 };
187 }; 187 };
188 }; 188 };
189 189
190 - | 190 - |
191 #include <dt-bindings/gpio/gpio.h> 191 #include <dt-bindings/gpio/gpio.h>
192 192
193 mux1: mux-controller { 193 mux1: mux-controller {
194 compatible = "gpio-mux"; 194 compatible = "gpio-mux";
195 #mux-state-cells = <1>; 195 #mux-state-cells = <1>;
196 mux-gpios = <&exp_som 2 GPIO_ACTIVE_HI 196 mux-gpios = <&exp_som 2 GPIO_ACTIVE_HIGH>;
197 }; 197 };
198 198
199 transceiver4: can-phy4 { 199 transceiver4: can-phy4 {
200 compatible = "ti,tcan1042"; 200 compatible = "ti,tcan1042";
201 #phy-cells = <0>; 201 #phy-cells = <0>;
202 max-bitrate = <5000000>; 202 max-bitrate = <5000000>;
203 standby-gpios = <&exp_som 7 GPIO_ACTIV 203 standby-gpios = <&exp_som 7 GPIO_ACTIVE_HIGH>;
204 mux-states = <&mux1 1>; 204 mux-states = <&mux1 1>;
205 }; 205 };
206 ... 206 ...
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