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@st.com>
11  - Olivier Moysan <olivier.moysan@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    maxItems: 2
42
43  clock-names:
44    items:
45      - const: dfsdm
46      - const: audio
47    minItems: 1
48    maxItems: 2
49
50  "#address-cells":
51    const: 1
52
53  "#size-cells":
54    const: 0
55
56  spi-max-frequency:
57    description:
58      SPI clock OUT frequency (Hz). Requested only for SPI master mode.
59      This clock must be set according to the "clock" property.
60      Frequency must be a multiple of the rcc clock frequency.
61      If not, SPI CLKOUT frequency will not be accurate.
62    maximum: 20000000
63
64required:
65  - compatible
66  - reg
67  - clocks
68  - clock-names
69  - "#address-cells"
70  - "#size-cells"
71
72additionalProperties: false
73
74patternProperties:
75  "^filter@[0-9]+$":
76    type: object
77    description: child node
78
79    properties:
80      compatible:
81        enum:
82          - st,stm32-dfsdm-adc
83          - st,stm32-dfsdm-dmic
84
85      reg:
86        description: Specifies the DFSDM filter instance used.
87        maxItems: 1
88
89      interrupts:
90        maxItems: 1
91
92      st,adc-channels:
93        description: |
94          List of single-ended channels muxed for this ADC.
95          On stm32h7 and stm32mp1:
96          - For st,stm32-dfsdm-adc: up to 8 channels numbered from 0 to 7.
97          - For st,stm32-dfsdm-dmic: 1 channel numbered from 0 to 7.
98        $ref: /schemas/types.yaml#/definitions/uint32-array
99        items:
100          minimum: 0
101          maximum: 7
102
103      st,adc-channel-names:
104        description: List of single-ended channel names.
105        $ref: /schemas/types.yaml#/definitions/string-array
106
107      st,filter-order:
108        description: |
109          SinC filter order from 0 to 5.
110          - 0: FastSinC
111          - [1-5]: order 1 to 5.
112          For audio purpose it is recommended to use order 3 to 5.
113        $ref: /schemas/types.yaml#/definitions/uint32
114        items:
115          minimum: 0
116          maximum: 5
117
118      "#io-channel-cells":
119        const: 1
120
121      st,adc-channel-types:
122        description: |
123          Single-ended channel input type.
124          - "SPI_R": SPI with data on rising edge (default)
125          - "SPI_F": SPI with data on falling edge
126          - "MANCH_R": manchester codec, rising edge = logic 0, falling edge = logic 1
127          - "MANCH_F": manchester codec, rising edge = logic 1, falling edge = logic 0
128        items:
129          enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
130        $ref: /schemas/types.yaml#/definitions/non-unique-string-array
131
132      st,adc-channel-clk-src:
133        description: |
134          Conversion clock source.
135          - "CLKIN": external SPI clock (CLKIN x)
136          - "CLKOUT": internal SPI clock (CLKOUT) (default)
137          - "CLKOUT_F": internal SPI clock divided by 2 (falling edge).
138          - "CLKOUT_R": internal SPI clock divided by 2 (rising edge).
139        items:
140          enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
141        $ref: /schemas/types.yaml#/definitions/non-unique-string-array
142
143      st,adc-alt-channel:
144        description:
145          Must be defined if two sigma delta modulators are
146          connected on same SPI input.
147          If not set, channel n is connected to SPI input n.
148          If set, channel n is connected to SPI input n + 1.
149        type: boolean
150
151      st,filter0-sync:
152        description:
153          Set to 1 to synchronize with DFSDM filter instance 0.
154          Used for multi microphones synchronization.
155        type: boolean
156
157      dmas:
158        maxItems: 1
159
160      dma-names:
161        items:
162          - const: rx
163
164    required:
165      - compatible
166      - reg
167      - interrupts
168      - st,adc-channels
169      - st,adc-channel-names
170      - st,filter-order
171      - "#io-channel-cells"
172
173    allOf:
174      - if:
175          properties:
176            compatible:
177              contains:
178                const: st,stm32-dfsdm-adc
179
180      - then:
181          properties:
182            st,adc-channels:
183              minItems: 1
184              maxItems: 8
185
186            st,adc-channel-names:
187              minItems: 1
188              maxItems: 8
189
190            st,adc-channel-types:
191              minItems: 1
192              maxItems: 8
193
194            st,adc-channel-clk-src:
195              minItems: 1
196              maxItems: 8
197
198            io-channels:
199              description:
200                From common IIO binding. Used to pipe external sigma delta
201                modulator or internal ADC output to DFSDM channel.
202                This is not required for "st,stm32-dfsdm-pdm" compatibility as
203                PDM microphone is binded in Audio DT node.
204
205          required:
206            - io-channels
207
208      - if:
209          properties:
210            compatible:
211              contains:
212                const: st,stm32-dfsdm-dmic
213
214      - then:
215          properties:
216            st,adc-channels:
217              maxItems: 1
218
219            st,adc-channel-names:
220              maxItems: 1
221
222            st,adc-channel-types:
223              maxItems: 1
224
225            st,adc-channel-clk-src:
226              maxItems: 1
227
228          required:
229            - dmas
230            - dma-names
231
232          patternProperties:
233            "^dfsdm-dai+$":
234              type: object
235              description: child node
236
237              properties:
238                "#sound-dai-cells":
239                  const: 0
240
241                io-channels:
242                  description:
243                    From common IIO binding. Used to pipe external sigma delta
244                    modulator or internal ADC output to DFSDM channel.
245
246              required:
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