xref: /linux/Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml (revision 3a39d672e7f48b8d6b91a09afa4b55352773b4b5) 
1# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2%YAML 1.2
3---
4$id: http://devicetree.org/schemas/iio/adc/st,stm32-dfsdm-adc.yaml#
5$schema: http://devicetree.org/meta-schemas/core.yaml#
6
7title: STMicroelectronics STM32 DFSDM ADC device driver
8
9maintainers:
10  - Fabrice Gasnier <fabrice.gasnier@foss.st.com>
11  - Olivier Moysan <olivier.moysan@foss.st.com>
12
13description: |
14  STM32 DFSDM ADC is a sigma delta analog-to-digital converter dedicated to
15  interface external sigma delta modulators to STM32 micro controllers.
16  It is mainly targeted for:
17  - Sigma delta modulators (motor control, metering...)
18  - PDM microphones (audio digital microphone)
19
20  It features up to 8 serial digital interfaces (SPI or Manchester) and
21  up to 4 filters on stm32h7 or 6 filters on stm32mp1.
22
23  Each child node matches with a filter instance.
24
25properties:
26  compatible:
27    enum:
28      - st,stm32h7-dfsdm
29      - st,stm32mp1-dfsdm
30
31  reg:
32    maxItems: 1
33
34  clocks:
35    items:
36      - description:
37          Internal clock used for DFSDM digital processing and control blocks.
38          dfsdm clock can also feed CLKOUT, when CLKOUT is used.
39      - description: audio clock can be used as an alternate to feed CLKOUT.
40    minItems: 1
41
42  clock-names:
43    items:
44      - const: dfsdm
45      - const: audio
46    minItems: 1
47
48  "#address-cells":
49    const: 1
50
51  "#size-cells":
52    const: 0
53
54  spi-max-frequency:
55    description:
56      SPI clock OUT frequency (Hz). Requested only for SPI master mode.
57      This clock must be set according to the "clock" property.
58      Frequency must be a multiple of the rcc clock frequency.
59      If not, SPI CLKOUT frequency will not be accurate.
60    maximum: 20000000
61
62  access-controllers:
63    minItems: 1
64    maxItems: 2
65
66required:
67  - compatible
68  - reg
69  - clocks
70  - clock-names
71  - "#address-cells"
72  - "#size-cells"
73
74additionalProperties: false
75
76patternProperties:
77  "^filter@[0-9]+$":
78    type: object
79    unevaluatedProperties: false
80    description: child node
81
82    properties:
83      compatible:
84        enum:
85          - st,stm32-dfsdm-adc
86          - st,stm32-dfsdm-dmic
87
88      reg:
89        description: Specifies the DFSDM filter instance used.
90        maxItems: 1
91
92      interrupts:
93        maxItems: 1
94
95      st,adc-channels:
96        description: |
97          List of single-ended channels muxed for this ADC.
98          On stm32h7 and stm32mp1:
99          - For st,stm32-dfsdm-adc: up to 8 channels numbered from 0 to 7.
100          - For st,stm32-dfsdm-dmic: 1 channel numbered from 0 to 7.
101        $ref: /schemas/types.yaml#/definitions/uint32-array
102        items:
103          minimum: 0
104          maximum: 7
105        deprecated: true
106
107      st,adc-channel-names:
108        description: List of single-ended channel names.
109        deprecated: true
110
111      st,filter-order:
112        description: |
113          SinC filter order from 0 to 5.
114          - 0: FastSinC
115          - [1-5]: order 1 to 5.
116          For audio purpose it is recommended to use order 3 to 5.
117        $ref: /schemas/types.yaml#/definitions/uint32
118        maximum: 5
119
120      "#io-channel-cells":
121        const: 1
122
123      '#address-cells':
124        const: 1
125
126      '#size-cells':
127        const: 0
128
129      st,adc-channel-types:
130        description: |
131          Single-ended channel input type.
132          - "SPI_R": SPI with data on rising edge (default)
133          - "SPI_F": SPI with data on falling edge
134          - "MANCH_R": manchester codec, rising edge = logic 0, falling edge = logic 1
135          - "MANCH_F": manchester codec, rising edge = logic 1, falling edge = logic 0
136        items:
137          enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
138        $ref: /schemas/types.yaml#/definitions/non-unique-string-array
139        deprecated: true
140
141      st,adc-channel-clk-src:
142        description: |
143          Conversion clock source.
144          - "CLKIN": external SPI clock (CLKIN x)
145          - "CLKOUT": internal SPI clock (CLKOUT) (default)
146          - "CLKOUT_F": internal SPI clock divided by 2 (falling edge).
147          - "CLKOUT_R": internal SPI clock divided by 2 (rising edge).
148        items:
149          enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
150        $ref: /schemas/types.yaml#/definitions/non-unique-string-array
151        deprecated: true
152
153      st,adc-alt-channel:
154        description:
155          Must be defined if two sigma delta modulators are
156          connected on same SPI input.
157          If not set, channel n is connected to SPI input n.
158          If set, channel n is connected to SPI input n + 1.
159        type: boolean
160        deprecated: true
161
162      st,filter0-sync:
163        description:
164          Set to 1 to synchronize with DFSDM filter instance 0.
165          Used for multi microphones synchronization.
166        type: boolean
167
168      dmas:
169        maxItems: 1
170
171      dma-names:
172        items:
173          - const: rx
174
175    required:
176      - compatible
177      - reg
178      - interrupts
179      - st,filter-order
180      - "#io-channel-cells"
181
182    patternProperties:
183      "^channel@[0-7]$":
184        type: object
185        $ref: adc.yaml
186        unevaluatedProperties: false
187        description: Represents the external channels which are connected to the DFSDM.
188
189        properties:
190          reg:
191            maximum: 7
192
193          label:
194            description:
195              Unique name to identify which channel this is.
196
197          st,adc-channel-type:
198            description: |
199              Single-ended channel input type.
200              - "SPI_R": SPI with data on rising edge (default)
201              - "SPI_F": SPI with data on falling edge
202              - "MANCH_R": manchester codec, rising edge = logic 0, falling edge = logic 1
203              - "MANCH_F": manchester codec, rising edge = logic 1, falling edge = logic 0
204            $ref: /schemas/types.yaml#/definitions/string
205            enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
206
207          st,adc-channel-clk-src:
208            description: |
209              Conversion clock source.
210              - "CLKIN": external SPI clock (CLKIN x)
211              - "CLKOUT": internal SPI clock (CLKOUT) (default)
212              - "CLKOUT_F": internal SPI clock divided by 2 (falling edge).
213              - "CLKOUT_R": internal SPI clock divided by 2 (rising edge).
214            $ref: /schemas/types.yaml#/definitions/string
215            enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
216
217          st,adc-alt-channel:
218            description:
219              Must be defined if two sigma delta modulators are
220              connected on same SPI input.
221              If not set, channel n is connected to SPI input n.
222              If set, channel n is connected to SPI input n + 1.
223            type: boolean
224
225          io-backends:
226            description:
227              Used to pipe external sigma delta modulator or internal ADC backend to DFSDM channel.
228            maxItems: 1
229
230        required:
231          - reg
232
233    allOf:
234      - if:
235          properties:
236            compatible:
237              contains:
238                const: st,stm32-dfsdm-adc
239
240        then:
241          properties:
242            st,adc-channels:
243              minItems: 1
244              maxItems: 8
245
246            st,adc-channel-names:
247              minItems: 1
248              maxItems: 8
249
250            st,adc-channel-types:
251              minItems: 1
252              maxItems: 8
253
254            st,adc-channel-clk-src:
255              minItems: 1
256              maxItems: 8
257
258            io-channels:
259              description:
260                From common IIO binding. Used to pipe external sigma delta
261                modulator or internal ADC output to DFSDM channel.
262              deprecated: true
263
264          if:
265            required:
266              - st,adc-channels
267          then:
268            required:
269              - io-channels
270
271          patternProperties:
272            "^channel@[0-7]$":
273              required:
274                - io-backends
275
276      - if:
277          properties:
278            compatible:
279              contains:
280                const: st,stm32-dfsdm-dmic
281
282        then:
283          properties:
284            st,adc-channels:
285              maxItems: 1
286
287            st,adc-channel-names:
288              maxItems: 1
289
290            st,adc-channel-types:
291              maxItems: 1
292
293            st,adc-channel-clk-src:
294              maxItems: 1
295
296          required:
297            - dmas
298            - dma-names
299
300          patternProperties:
301            "^dfsdm-dai+$":
302              type: object
303              additionalProperties: false
304              description: child node
305
306              properties:
307                compatible:
308                  enum:
309                    - st,stm32h7-dfsdm-dai
310
311                "#sound-dai-cells":
312                  const: 0
313
314                io-channels:
315                  description:
316                    From common IIO binding. Used to pipe external sigma delta
317                    modulator or internal ADC output to DFSDM channel.
318
319                port:
320                  $ref: /schemas/sound/audio-graph-port.yaml#
321                  unevaluatedProperties: false
322
323              required:
324                - compatible
325                - "#sound-dai-cells"
326                - io-channels
327
328allOf:
329  - if:
330      properties:
331        compatible:
332          contains:
333            const: st,stm32h7-dfsdm
334
335    then:
336      patternProperties:
337        "^filter@[0-9]+$":
338          properties:
339            reg:
340              items:
341                minimum: 0
342                maximum: 3
343
344  - if:
345      properties:
346        compatible:
347          contains:
348            const: st,stm32mp1-dfsdm
349
350    then:
351      patternProperties:
352        "^filter@[0-9]+$":
353          properties:
354            reg:
355              items:
356                minimum: 0
357                maximum: 5
358
359examples:
360  - |
361    #include <dt-bindings/interrupt-controller/arm-gic.h>
362    #include <dt-bindings/clock/stm32mp1-clks.h>
363    dfsdm: dfsdm@4400d000 {
364      compatible = "st,stm32mp1-dfsdm";
365      reg = <0x4400d000 0x800>;
366      clocks = <&rcc DFSDM_K>, <&rcc ADFSDM_K>;
367      clock-names = "dfsdm", "audio";
368      #address-cells = <1>;
369      #size-cells = <0>;
370
371      // Example 1: Audio use case with generic binding
372      dfsdm0: filter@0 {
373        compatible = "st,stm32-dfsdm-dmic";
374        reg = <0>;
375        interrupts = <GIC_SPI 110 IRQ_TYPE_LEVEL_HIGH>;
376        dmas = <&dmamux1 101 0x400 0x01>;
377        dma-names = "rx";
378        #io-channel-cells = <1>;
379        #address-cells = <1>;
380        #size-cells = <0>;
381        st,filter-order = <5>;
382
383        channel@1 {
384          reg = <1>;
385          label = "dmic0";
386          st,adc-channel-type = "SPI_R";
387          st,adc-channel-clk-src = "CLKOUT";
388          st,adc-alt-channel;
389        };
390
391        asoc_pdm0: dfsdm-dai {
392          compatible = "st,stm32h7-dfsdm-dai";
393          #sound-dai-cells = <0>;
394          io-channels = <&dfsdm0 0>;
395        };
396      };
397
398      // Example 2: Analog use case with generic binding
399      dfsdm1: filter@1 {
400        compatible = "st,stm32-dfsdm-adc";
401        reg = <1>;
402        interrupts = <GIC_SPI 111 IRQ_TYPE_LEVEL_HIGH>;
403        dmas = <&dmamux1 102 0x400 0x01>;
404        dma-names = "rx";
405        st,filter-order = <1>;
406        #io-channel-cells = <1>;
407        #address-cells = <1>;
408        #size-cells = <0>;
409
410        channel@2 {
411          reg = <2>;
412          label = "in2";
413          st,adc-channel-type = "SPI_F";
414          st,adc-channel-clk-src = "CLKOUT";
415          st,adc-alt-channel;
416          io-backends = <&sd_adc2>;
417        };
418
419        channel@3 {
420          reg = <3>;
421          label = "in3";
422          st,adc-channel-type = "SPI_R";
423          st,adc-channel-clk-src = "CLKOUT";
424          io-backends = <&sd_adc3>;
425        };
426      };
427    };
428
429...
430