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