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    unevaluatedProperties: false
76    description: child node
77
78    properties:
79      compatible:
80        enum:
81          - st,stm32-dfsdm-adc
82          - st,stm32-dfsdm-dmic
83
84      reg:
85        description: Specifies the DFSDM filter instance used.
86        maxItems: 1
87
88      interrupts:
89        maxItems: 1
90
91      st,adc-channels:
92        description: |
93          List of single-ended channels muxed for this ADC.
94          On stm32h7 and stm32mp1:
95          - For st,stm32-dfsdm-adc: up to 8 channels numbered from 0 to 7.
96          - For st,stm32-dfsdm-dmic: 1 channel numbered from 0 to 7.
97        $ref: /schemas/types.yaml#/definitions/uint32-array
98        items:
99          minimum: 0
100          maximum: 7
101
102      st,adc-channel-names:
103        description: List of single-ended channel names.
104
105      st,filter-order:
106        description: |
107          SinC filter order from 0 to 5.
108          - 0: FastSinC
109          - [1-5]: order 1 to 5.
110          For audio purpose it is recommended to use order 3 to 5.
111        $ref: /schemas/types.yaml#/definitions/uint32
112        maximum: 5
113
114      "#io-channel-cells":
115        const: 1
116
117      st,adc-channel-types:
118        description: |
119          Single-ended channel input type.
120          - "SPI_R": SPI with data on rising edge (default)
121          - "SPI_F": SPI with data on falling edge
122          - "MANCH_R": manchester codec, rising edge = logic 0, falling edge = logic 1
123          - "MANCH_F": manchester codec, rising edge = logic 1, falling edge = logic 0
124        items:
125          enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
126        $ref: /schemas/types.yaml#/definitions/non-unique-string-array
127
128      st,adc-channel-clk-src:
129        description: |
130          Conversion clock source.
131          - "CLKIN": external SPI clock (CLKIN x)
132          - "CLKOUT": internal SPI clock (CLKOUT) (default)
133          - "CLKOUT_F": internal SPI clock divided by 2 (falling edge).
134          - "CLKOUT_R": internal SPI clock divided by 2 (rising edge).
135        items:
136          enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
137        $ref: /schemas/types.yaml#/definitions/non-unique-string-array
138
139      st,adc-alt-channel:
140        description:
141          Must be defined if two sigma delta modulators are
142          connected on same SPI input.
143          If not set, channel n is connected to SPI input n.
144          If set, channel n is connected to SPI input n + 1.
145        type: boolean
146
147      st,filter0-sync:
148        description:
149          Set to 1 to synchronize with DFSDM filter instance 0.
150          Used for multi microphones synchronization.
151        type: boolean
152
153      dmas:
154        maxItems: 1
155
156      dma-names:
157        items:
158          - const: rx
159
160    required:
161      - compatible
162      - reg
163      - interrupts
164      - st,adc-channels
165      - st,adc-channel-names
166      - st,filter-order
167      - "#io-channel-cells"
168
169    allOf:
170      - if:
171          properties:
172            compatible:
173              contains:
174                const: st,stm32-dfsdm-adc
175
176        then:
177          properties:
178            st,adc-channels:
179              minItems: 1
180              maxItems: 8
181
182            st,adc-channel-names:
183              minItems: 1
184              maxItems: 8
185
186            st,adc-channel-types:
187              minItems: 1
188              maxItems: 8
189
190            st,adc-channel-clk-src:
191              minItems: 1
192              maxItems: 8
193
194            io-channels:
195              description:
196                From common IIO binding. Used to pipe external sigma delta
197                modulator or internal ADC output to DFSDM channel.
198
199          required:
200            - io-channels
201
202      - if:
203          properties:
204            compatible:
205              contains:
206                const: st,stm32-dfsdm-dmic
207
208        then:
209          properties:
210            st,adc-channels:
211              maxItems: 1
212
213            st,adc-channel-names:
214              maxItems: 1
215
216            st,adc-channel-types:
217              maxItems: 1
218
219            st,adc-channel-clk-src:
220              maxItems: 1
221
222          required:
223            - dmas
224            - dma-names
225
226          patternProperties:
227            "^dfsdm-dai+$":
228              type: object
229              additionalProperties: false
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