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
62required:
63  - compatible
64  - reg
65  - clocks
66  - clock-names
67  - "#address-cells"
68  - "#size-cells"
69
70additionalProperties: false
71
72patternProperties:
73  "^filter@[0-9]+$":
74    type: object
75    description: child node
76
77    properties:
78      compatible:
79        enum:
80          - st,stm32-dfsdm-adc
81          - st,stm32-dfsdm-dmic
82
83      reg:
84        description: Specifies the DFSDM filter instance used.
85        maxItems: 1
86
87      interrupts:
88        maxItems: 1
89
90      st,adc-channels:
91        description: |
92          List of single-ended channels muxed for this ADC.
93          On stm32h7 and stm32mp1:
94          - For st,stm32-dfsdm-adc: up to 8 channels numbered from 0 to 7.
95          - For st,stm32-dfsdm-dmic: 1 channel numbered from 0 to 7.
96        $ref: /schemas/types.yaml#/definitions/uint32-array
97        items:
98          minimum: 0
99          maximum: 7
100
101      st,adc-channel-names:
102        description: List of single-ended channel names.
103
104      st,filter-order:
105        description: |
106          SinC filter order from 0 to 5.
107          - 0: FastSinC
108          - [1-5]: order 1 to 5.
109          For audio purpose it is recommended to use order 3 to 5.
110        $ref: /schemas/types.yaml#/definitions/uint32
111        items:
112          minimum: 0
113          maximum: 5
114
115      "#io-channel-cells":
116        const: 1
117
118      st,adc-channel-types:
119        description: |
120          Single-ended channel input type.
121          - "SPI_R": SPI with data on rising edge (default)
122          - "SPI_F": SPI with data on falling edge
123          - "MANCH_R": manchester codec, rising edge = logic 0, falling edge = logic 1
124          - "MANCH_F": manchester codec, rising edge = logic 1, falling edge = logic 0
125        items:
126          enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
127        $ref: /schemas/types.yaml#/definitions/non-unique-string-array
128
129      st,adc-channel-clk-src:
130        description: |
131          Conversion clock source.
132          - "CLKIN": external SPI clock (CLKIN x)
133          - "CLKOUT": internal SPI clock (CLKOUT) (default)
134          - "CLKOUT_F": internal SPI clock divided by 2 (falling edge).
135          - "CLKOUT_R": internal SPI clock divided by 2 (rising edge).
136        items:
137          enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
138        $ref: /schemas/types.yaml#/definitions/non-unique-string-array
139
140      st,adc-alt-channel:
141        description:
142          Must be defined if two sigma delta modulators are
143          connected on same SPI input.
144          If not set, channel n is connected to SPI input n.
145          If set, channel n is connected to SPI input n + 1.
146        type: boolean
147
148      st,filter0-sync:
149        description:
150          Set to 1 to synchronize with DFSDM filter instance 0.
151          Used for multi microphones synchronization.
152        type: boolean
153
154      dmas:
155        maxItems: 1
156
157      dma-names:
158        items:
159          - const: rx
160
161    required:
162      - compatible
163      - reg
164      - interrupts
165      - st,adc-channels
166      - st,adc-channel-names
167      - st,filter-order
168      - "#io-channel-cells"
169
170    allOf:
171      - if:
172          properties:
173            compatible:
174              contains:
175                const: st,stm32-dfsdm-adc
176
177      - then:
178          properties:
179            st,adc-channels:
180              minItems: 1
181              maxItems: 8
182
183            st,adc-channel-names:
184              minItems: 1
185              maxItems: 8
186
187            st,adc-channel-types:
188              minItems: 1
189              maxItems: 8
190
191            st,adc-channel-clk-src:
192              minItems: 1
193              maxItems: 8
194
195            io-channels:
196              description:
197                From common IIO binding. Used to pipe external sigma delta
198                modulator or internal ADC output to DFSDM channel.
199
200          required:
201            - io-channels
202
203      - if:
204          properties:
205            compatible:
206              contains:
207                const: st,stm32-dfsdm-dmic
208
209      - then:
210          properties:
211            st,adc-channels:
212              maxItems: 1
213
214            st,adc-channel-names:
215              maxItems: 1
216
217            st,adc-channel-types:
218              maxItems: 1
219
220            st,adc-channel-clk-src:
221              maxItems: 1
222
223          required:
224            - dmas
225            - dma-names
226
227          patternProperties:
228            "^dfsdm-dai+$":
229              type: object
230              description: child node
231
232              properties:
233                compatible:
234                  enum:
235                    - st,stm32h7-dfsdm-dai
236
237                "#sound-dai-cells":
238                  const: 0
239
240                io-channels:
241                  description:
242                    From common IIO binding. Used to pipe external sigma delta
243                    modulator or internal ADC output to DFSDM channel.
244
245              required:
246                - compatible
247                - "#sound-dai-cells"
248                - io-channels
249
250allOf:
251  - if:
252      properties:
253        compatible:
254          contains:
255            const: st,stm32h7-dfsdm
256
257  - then:
258      patternProperties:
259        "^filter@[0-9]+$":
260          properties:
261            reg:
262              items:
263                minimum: 0
264                maximum: 3
265
266  - if:
267      properties:
268        compatible:
269          contains:
270            const: st,stm32mp1-dfsdm
271
272  - then:
273      patternProperties:
274        "^filter@[0-9]+$":
275          properties:
276            reg:
277              items:
278                minimum: 0
279                maximum: 5
280
281examples:
282  - |
283    #include <dt-bindings/interrupt-controller/arm-gic.h>
284    #include <dt-bindings/clock/stm32mp1-clks.h>
285    dfsdm: dfsdm@4400d000 {
286      compatible = "st,stm32mp1-dfsdm";
287      reg = <0x4400d000 0x800>;
288      clocks = <&rcc DFSDM_K>, <&rcc ADFSDM_K>;
289      clock-names = "dfsdm", "audio";
290      #address-cells = <1>;
291      #size-cells = <0>;
292
293      dfsdm0: filter@0 {
294        compatible = "st,stm32-dfsdm-dmic";
295        reg = <0>;
296        interrupts = <GIC_SPI 110 IRQ_TYPE_LEVEL_HIGH>;
297        dmas = <&dmamux1 101 0x400 0x01>;
298        dma-names = "rx";
299        #io-channel-cells = <1>;
300        st,adc-channels = <1>;
301        st,adc-channel-names = "dmic0";
302        st,adc-channel-types = "SPI_R";
303        st,adc-channel-clk-src = "CLKOUT";
304        st,filter-order = <5>;
305
306        asoc_pdm0: dfsdm-dai {
307          compatible = "st,stm32h7-dfsdm-dai";
308          #sound-dai-cells = <0>;
309          io-channels = <&dfsdm0 0>;
310        };
311      };
312
313      dfsdm_pdm1: filter@1 {
314        compatible = "st,stm32-dfsdm-adc";
315        reg = <1>;
316        interrupts = <GIC_SPI 111 IRQ_TYPE_LEVEL_HIGH>;
317        dmas = <&dmamux1 102 0x400 0x01>;
318        dma-names = "rx";
319        #io-channel-cells = <1>;
320        st,adc-channels = <2 3>;
321        st,adc-channel-names = "in2", "in3";
322        st,adc-channel-types = "SPI_R", "SPI_R";
323        st,adc-channel-clk-src = "CLKOUT_F", "CLKOUT_F";
324        io-channels = <&sd_adc2 &sd_adc3>;
325        st,filter-order = <1>;
326      };
327    };
328
329...
330