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
203          required:
204            - io-channels
205
206      - if:
207          properties:
208            compatible:
209              contains:
210                const: st,stm32-dfsdm-dmic
211
212      - then:
213          properties:
214            st,adc-channels:
215              maxItems: 1
216
217            st,adc-channel-names:
218              maxItems: 1
219
220            st,adc-channel-types:
221              maxItems: 1
222
223            st,adc-channel-clk-src:
224              maxItems: 1
225
226          required:
227            - dmas
228            - dma-names
229
230          patternProperties:
231            "^dfsdm-dai+$":
232              type: object
233              description: child node
234
235              properties:
236                compatible:
237                  enum:
238                    - st,stm32h7-dfsdm-dai
239
240                "#sound-dai-cells":
241                  const: 0
242
243                io-channels:
244                  description:
245                    From common IIO binding. Used to pipe external sigma delta
246                    modulator or internal ADC output to DFSDM channel.
247
248              required:
249                - compatible
250                - "#sound-dai-cells"
251                - io-channels
252
253allOf:
254  - if:
255      properties:
256        compatible:
257          contains:
258            const: st,stm32h7-dfsdm
259
260  - then:
261      patternProperties:
262        "^filter@[0-9]+$":
263          properties:
264            reg:
265              items:
266                minimum: 0
267                maximum: 3
268
269  - if:
270      properties:
271        compatible:
272          contains:
273            const: st,stm32mp1-dfsdm
274
275  - then:
276      patternProperties:
277        "^filter@[0-9]+$":
278          properties:
279            reg:
280              items:
281                minimum: 0
282                maximum: 5
283
284examples:
285  - |
286    #include <dt-bindings/interrupt-controller/arm-gic.h>
287    #include <dt-bindings/clock/stm32mp1-clks.h>
288    dfsdm: dfsdm@4400d000 {
289      compatible = "st,stm32mp1-dfsdm";
290      reg = <0x4400d000 0x800>;
291      clocks = <&rcc DFSDM_K>, <&rcc ADFSDM_K>;
292      clock-names = "dfsdm", "audio";
293      #address-cells = <1>;
294      #size-cells = <0>;
295
296      dfsdm0: filter@0 {
297        compatible = "st,stm32-dfsdm-dmic";
298        reg = <0>;
299        interrupts = <GIC_SPI 110 IRQ_TYPE_LEVEL_HIGH>;
300        dmas = <&dmamux1 101 0x400 0x01>;
301        dma-names = "rx";
302        #io-channel-cells = <1>;
303        st,adc-channels = <1>;
304        st,adc-channel-names = "dmic0";
305        st,adc-channel-types = "SPI_R";
306        st,adc-channel-clk-src = "CLKOUT";
307        st,filter-order = <5>;
308
309        asoc_pdm0: dfsdm-dai {
310          compatible = "st,stm32h7-dfsdm-dai";
311          #sound-dai-cells = <0>;
312          io-channels = <&dfsdm0 0>;
313        };
314      };
315
316      dfsdm_pdm1: filter@1 {
317        compatible = "st,stm32-dfsdm-adc";
318        reg = <1>;
319        interrupts = <GIC_SPI 111 IRQ_TYPE_LEVEL_HIGH>;
320        dmas = <&dmamux1 102 0x400 0x01>;
321        dma-names = "rx";
322        #io-channel-cells = <1>;
323        st,adc-channels = <2 3>;
324        st,adc-channel-names = "in2", "in3";
325        st,adc-channel-types = "SPI_R", "SPI_R";
326        st,adc-channel-clk-src = "CLKOUT_F", "CLKOUT_F";
327        io-channels = <&sd_adc2 &sd_adc3>;
328        st,filter-order = <1>;
329      };
330    };
331
332...
333