1 # SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 # Copyright (C) 2019 Renesas Electronics Corp.
3 %YAML 1.2
4 ---
5 $id: http://devicetree.org/schemas/media/i2c/maxim,max9286.yaml#
6 $schema: http://devicetree.org/meta-schemas/core.yaml#
7
8 title: Maxim Integrated Quad GMSL Deserializer
9
10 maintainers:
11 - Jacopo Mondi <jacopo+renesas@jmondi.org>
12 - Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>
13 - Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
14 - Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>
15
16 description: |
17 The MAX9286 deserializer receives video data on up to 4 Gigabit Multimedia
18 Serial Links (GMSL) and outputs them on a CSI-2 D-PHY port using up to 4 data
19 lanes.
20
21 In addition to video data, the GMSL links carry a bidirectional control
22 channel that encapsulates I2C messages. The MAX9286 forwards all I2C traffic
23 not addressed to itself to the other side of the links, where a GMSL
24 serializer will output it on a local I2C bus. In the other direction all I2C
25 traffic received over GMSL by the MAX9286 is output on the local I2C bus.
26
27 properties:
28 '#address-cells':
29 const: 1
30
31 '#size-cells':
32 const: 0
33
34 compatible:
35 const: maxim,max9286
36
37 reg:
38 description: I2C device address
39 maxItems: 1
40
41 poc-supply:
42 description: Regulator providing Power over Coax to all the ports
43
44 enable-gpios:
45 description: GPIO connected to the \#PWDN pin with inverted polarity
46 maxItems: 1
47
48 gpio-controller: true
49
50 '#gpio-cells':
51 const: 2
52
53 maxim,bus-width:
54 $ref: /schemas/types.yaml#/definitions/uint32
55 enum: [ 24, 27, 32 ]
56 description: |
57 The GMSL serial data bus width. This setting is normally controlled by
58 the BWS pin, but may be overridden with this property. The value must
59 match the configuration of the remote serializers.
60
61 maxim,i2c-remote-bus-hz:
62 enum: [ 8470, 28300, 84700, 105000, 173000, 339000, 533000, 837000 ]
63 default: 105000
64 description: |
65 The I2C clock frequency for the remote I2C buses. The value must match
66 the configuration of the remote serializers.
67
68 maxim,reverse-channel-microvolt:
69 minimum: 30000
70 maximum: 200000
71 default: 170000
72 description: |
73 Initial amplitude of the reverse control channel, in micro volts.
74
75 The initial amplitude shall be adjusted to a value compatible with the
76 configuration of the connected remote serializer.
77
78 Some camera modules (for example RDACM20) include an on-board MCU that
79 pre-programs the embedded serializer with power supply noise immunity
80 (high-threshold) enabled. A typical value of the deserializer's reverse
81 channel amplitude to communicate with pre-programmed serializers is
82 170000 micro volts.
83
84 A typical value for the reverse channel amplitude to communicate with
85 a remote serializer whose high-threshold noise immunity is not enabled
86 is 100000 micro volts
87
88 maxim,gpio-poc:
89 $ref: /schemas/types.yaml#/definitions/uint32-array
90 minItems: 2
91 maxItems: 2
92 description: |
93 Index of the MAX9286 gpio output line (0 or 1) that controls Power over
94 Coax to the cameras and its associated polarity flag.
95
96 The property accepts an array of two unsigned integers, the first being
97 the gpio line index (0 or 1) and the second being the gpio line polarity
98 flag (GPIO_ACTIVE_HIGH or GPIO_ACTIVE_LOW) as defined in
99 <include/dt-bindings/gpio/gpio.h>.
100
101 When the remote cameras power is controlled by one of the MAX9286 gpio
102 lines, this property has to be used to specify which line among the two
103 available ones controls the remote camera power enablement.
104
105 When this property is used it is not possible to register a gpio
106 controller as the gpio lines are controlled directly by the MAX9286 and
107 not available for consumers, nor the 'poc-supply' property should be
108 specified.
109
110 ports:
111 $ref: /schemas/graph.yaml#/properties/ports
112
113 properties:
114 port@0:
115 $ref: /schemas/graph.yaml#/properties/port
116 description: GMSL Input 0
117
118 port@1:
119 $ref: /schemas/graph.yaml#/properties/port
120 description: GMSL Input 1
121
122 port@2:
123 $ref: /schemas/graph.yaml#/properties/port
124 description: GMSL Input 2
125
126 port@3:
127 $ref: /schemas/graph.yaml#/properties/port
128 description: GMSL Input 3
129
130 port@4:
131 $ref: /schemas/graph.yaml#/$defs/port-base
132 unevaluatedProperties: false
133 description: CSI-2 Output
134
135 properties:
136 endpoint:
137 $ref: /schemas/media/video-interfaces.yaml#
138 unevaluatedProperties: false
139
140 properties:
141 data-lanes: true
142
143 required:
144 - data-lanes
145
146 required:
147 - port@4
148
149 i2c-mux:
150 type: object
151 $ref: /schemas/i2c/i2c-mux.yaml#
152 unevaluatedProperties: false
153 description: |
154 Each GMSL link is modelled as a child bus of an i2c bus multiplexer/switch.
155
156 patternProperties:
157 "^i2c@[0-3]$":
158 type: object
159 additionalProperties: false
160 description: |
161 Child node of the i2c bus multiplexer which represents a GMSL link.
162 Each serializer device on the GMSL link remote end is represented with
163 an i2c-mux child node. The MAX9286 chip supports up to 4 GMSL
164 channels.
165
166 properties:
167 reg:
168 description: The index of the GMSL channel.
169 maxItems: 1
170
171 '#address-cells':
172 const: 1
173
174 '#size-cells':
175 const: 0
176
177 patternProperties:
178 "^camera@[a-f0-9]+$":
179 type: object
180 description: |
181 The remote camera device, composed by a GMSL serializer and a
182 connected video source.
183
184 properties:
185 compatible:
186 description: The remote device compatible string.
187
188 reg:
189 minItems: 2
190 maxItems: 3
191 description: |
192 The I2C addresses to be assigned to the remote devices through
193 address reprogramming. The number of entries depends on the
194 requirements of the currently connected remote device.
195
196 port:
197 $ref: /schemas/graph.yaml#/properties/port
198 description: Connection to the MAX9286 sink.
199
200 required:
201 - compatible
202 - reg
203 - port
204
205 additionalProperties: false
206
207 patternProperties:
208 "^port[0-3]-poc-supply$":
209 description: Regulator providing Power over Coax for a particular port
210
211 required:
212 - compatible
213 - reg
214 - ports
215 - i2c-mux
216
217 allOf:
218 # Only one way of specifying power supplies is allowed: 'maxim,gpio-poc',
219 # 'poc-supply' or per-port poc-supply. Additionally, if 'maxim,gpio-poc' is
220 # present, then 'gpio-controller' isn't allowed.
221 - if:
222 required:
223 - maxim,gpio-poc
224 then:
225 properties:
226 poc-supply: false
227 gpio-controller: false
228 patternProperties:
229 "^port[0-3]-poc-supply$": false
230
231 - if:
232 required:
233 - poc-supply
234 then:
235 patternProperties:
236 "^port[0-3]-poc-supply$": false
237
238 additionalProperties: false
239
240 examples:
241 - |
242 #include <dt-bindings/gpio/gpio.h>
243
244 i2c@e66d8000 {
245 #address-cells = <1>;
246 #size-cells = <0>;
247
248 reg = <0 0xe66d8000>;
249
250 gmsl-deserializer@2c {
251 compatible = "maxim,max9286";
252 reg = <0x2c>;
253 poc-supply = <&camera_poc_12v>;
254 enable-gpios = <&gpio 13 GPIO_ACTIVE_HIGH>;
255
256 gpio-controller;
257 #gpio-cells = <2>;
258
259 maxim,i2c-remote-bus-hz = <339000>;
260 maxim,reverse-channel-microvolt = <170000>;
261
262 ports {
263 #address-cells = <1>;
264 #size-cells = <0>;
265
266 port@0 {
267 reg = <0>;
268
269 max9286_in0: endpoint {
270 remote-endpoint = <&rdacm20_out0>;
271 };
272 };
273
274 port@1 {
275 reg = <1>;
276
277 max9286_in1: endpoint {
278 remote-endpoint = <&rdacm20_out1>;
279 };
280 };
281
282 port@2 {
283 reg = <2>;
284
285 max9286_in2: endpoint {
286 remote-endpoint = <&rdacm20_out2>;
287 };
288 };
289
290 port@3 {
291 reg = <3>;
292
293 max9286_in3: endpoint {
294 remote-endpoint = <&rdacm20_out3>;
295 };
296 };
297
298 port@4 {
299 reg = <4>;
300
301 max9286_out: endpoint {
302 data-lanes = <1 2 3 4>;
303 remote-endpoint = <&csi40_in>;
304 };
305 };
306 };
307
308 i2c-mux {
309 #address-cells = <1>;
310 #size-cells = <0>;
311
312 i2c@0 {
313 #address-cells = <1>;
314 #size-cells = <0>;
315 reg = <0>;
316
317 camera@51 {
318 compatible = "imi,rdacm20";
319 reg = <0x51>, <0x61>;
320
321 port {
322 rdacm20_out0: endpoint {
323 remote-endpoint = <&max9286_in0>;
324 };
325 };
326
327 };
328 };
329
330 i2c@1 {
331 #address-cells = <1>;
332 #size-cells = <0>;
333 reg = <1>;
334
335 camera@52 {
336 compatible = "imi,rdacm20";
337 reg = <0x52>, <0x62>;
338
339 port {
340 rdacm20_out1: endpoint {
341 remote-endpoint = <&max9286_in1>;
342 };
343 };
344 };
345 };
346
347 i2c@2 {
348 #address-cells = <1>;
349 #size-cells = <0>;
350 reg = <2>;
351
352 camera@53 {
353 compatible = "imi,rdacm20";
354 reg = <0x53>, <0x63>;
355
356 port {
357 rdacm20_out2: endpoint {
358 remote-endpoint = <&max9286_in2>;
359 };
360 };
361 };
362 };
363
364 i2c@3 {
365 #address-cells = <1>;
366 #size-cells = <0>;
367 reg = <3>;
368
369 camera@54 {
370 compatible = "imi,rdacm20";
371 reg = <0x54>, <0x64>;
372
373 port {
374 rdacm20_out3: endpoint {
375 remote-endpoint = <&max9286_in3>;
376 };
377 };
378 };
379 };
380 };
381 };
382
383 /*
384 * Example of a deserializer that controls the camera Power over Coax
385 * through one of its gpio lines.
386 */
387 gmsl-deserializer@6c {
388 compatible = "maxim,max9286";
389 reg = <0x6c>;
390 enable-gpios = <&gpio 14 GPIO_ACTIVE_HIGH>;
391
392 /*
393 * The remote camera power is controlled by MAX9286 GPIO line #0.
394 * No 'poc-supply' nor 'gpio-controller' are specified.
395 */
396 maxim,gpio-poc = <0 GPIO_ACTIVE_LOW>;
397
398 /*
399 * Do not describe connections as they're the same as in the previous
400 * example.
401 */
402 ports {
403 #address-cells = <1>;
404 #size-cells = <0>;
405
406 port@4 {
407 reg = <4>;
408 };
409 };
410
411 i2c-mux {
412 #address-cells = <1>;
413 #size-cells = <0>;
414 };
415 };
416 };
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