Documentation/devicetree/bindings/iio/adc/st,stm32-dfsdm-adc.yaml

   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
   7 title: STMicroelectronics STM32 DFSDM ADC device driver
   8
   9 maintainers:
  10   - Fabrice Gasnier <fabrice.gasnier@st.com>
  11   - Olivier Moysan <olivier.moysan@st.com>
  12
  13 description: |
  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
  25 properties:
  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
  62 required:
  63   - compatible
  64   - reg
  65   - clocks
  66   - clock-names
  67   - "#address-cells"
  68   - "#size-cells"
  69
  70 additionalProperties: false
  71
  72 patternProperties:
  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         $ref: /schemas/types.yaml#/definitions/string-array
 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         items:
 113           minimum: 0
 114           maximum: 5
 115
 116       "#io-channel-cells":
 117         const: 1
 118
 119       st,adc-channel-types:
 120         description: |
 121           Single-ended channel input type.
 122           - "SPI_R": SPI with data on rising edge (default)
 123           - "SPI_F": SPI with data on falling edge
 124           - "MANCH_R": manchester codec, rising edge = logic 0, falling edge = logic 1
 125           - "MANCH_F": manchester codec, rising edge = logic 1, falling edge = logic 0
 126         items:
 127           enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
 128         $ref: /schemas/types.yaml#/definitions/non-unique-string-array
 129
 130       st,adc-channel-clk-src:
 131         description: |
 132           Conversion clock source.
 133           - "CLKIN": external SPI clock (CLKIN x)
 134           - "CLKOUT": internal SPI clock (CLKOUT) (default)
 135           - "CLKOUT_F": internal SPI clock divided by 2 (falling edge).
 136           - "CLKOUT_R": internal SPI clock divided by 2 (rising edge).
 137         items:
 138           enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
 139         $ref: /schemas/types.yaml#/definitions/non-unique-string-array
 140
 141       st,adc-alt-channel:
 142         description:
 143           Must be defined if two sigma delta modulators are
 144           connected on same SPI input.
 145           If not set, channel n is connected to SPI input n.
 146           If set, channel n is connected to SPI input n + 1.
 147         type: boolean
 148
 149       st,filter0-sync:
 150         description:
 151           Set to 1 to synchronize with DFSDM filter instance 0.
 152           Used for multi microphones synchronization.
 153         type: boolean
 154
 155       dmas:
 156         maxItems: 1
 157
 158       dma-names:
 159         items:
 160           - const: rx
 161
 162     required:
 163       - compatible
 164       - reg
 165       - interrupts
 166       - st,adc-channels
 167       - st,adc-channel-names
 168       - st,filter-order
 169       - "#io-channel-cells"
 170
 171     allOf:
 172       - if:
 173           properties:
 174             compatible:
 175               contains:
 176                 const: st,stm32-dfsdm-adc
 177
 178       - then:
 179           properties:
 180             st,adc-channels:
 181               minItems: 1
 182               maxItems: 8
 183
 184             st,adc-channel-names:
 185               minItems: 1
 186               maxItems: 8
 187
 188             st,adc-channel-types:
 189               minItems: 1
 190               maxItems: 8
 191
 192             st,adc-channel-clk-src:
 193               minItems: 1
 194               maxItems: 8
 195
 196             io-channels:
 197               description:
 198                 From common IIO binding. Used to pipe external sigma delta
 199                 modulator or internal ADC output to DFSDM channel.
 200
 201           required:
 202             - io-channels
 203
 204       - if:
 205           properties:
 206             compatible:
 207               contains:
 208                 const: st,stm32-dfsdm-dmic
 209
 210       - then:
 211           properties:
 212             st,adc-channels:
 213               maxItems: 1
 214
 215             st,adc-channel-names:
 216               maxItems: 1
 217
 218             st,adc-channel-types:
 219               maxItems: 1
 220
 221             st,adc-channel-clk-src:
 222               maxItems: 1
 223
 224           required:
 225             - dmas
 226             - dma-names
 227
 228           patternProperties:
 229             "^dfsdm-dai+$":
 230               type: object
 231               description: child node
 232
 233               properties:
 234                 compatible:
 235                   enum:
 236                     - st,stm32h7-dfsdm-dai
 237
 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                 - compatible
 248                 - "#sound-dai-cells"
 249                 - io-channels
 250
 251 allOf:
 252   - if:
 253       properties:
 254         compatible:
 255           contains:
 256             const: st,stm32h7-dfsdm
 257
 258   - then:
 259       patternProperties:
 260         "^filter@[0-9]+$":
 261           properties:
 262             reg:
 263               items:
 264                 minimum: 0
 265                 maximum: 3
 266
 267   - if:
 268       properties:
 269         compatible:
 270           contains:
 271             const: st,stm32mp1-dfsdm
 272
 273   - then:
 274       patternProperties:
 275         "^filter@[0-9]+$":
 276           properties:
 277             reg:
 278               items:
 279                 minimum: 0
 280                 maximum: 5
 281
 282 examples:
 283   - |
 284     #include <dt-bindings/interrupt-controller/arm-gic.h>
 285     #include <dt-bindings/clock/stm32mp1-clks.h>
 286     dfsdm: dfsdm@4400d000 {
 287       compatible = "st,stm32mp1-dfsdm";
 288       reg = <0x4400d000 0x800>;
 289       clocks = <&rcc DFSDM_K>, <&rcc ADFSDM_K>;
 290       clock-names = "dfsdm", "audio";
 291       #address-cells = <1>;
 292       #size-cells = <0>;
 293
 294       dfsdm0: filter@0 {
 295         compatible = "st,stm32-dfsdm-dmic";
 296         reg = <0>;
 297         interrupts = <GIC_SPI 110 IRQ_TYPE_LEVEL_HIGH>;
 298         dmas = <&dmamux1 101 0x400 0x01>;
 299         dma-names = "rx";
 300         #io-channel-cells = <1>;
 301         st,adc-channels = <1>;
 302         st,adc-channel-names = "dmic0";
 303         st,adc-channel-types = "SPI_R";
 304         st,adc-channel-clk-src = "CLKOUT";
 305         st,filter-order = <5>;
 306
 307         asoc_pdm0: dfsdm-dai {
 308           compatible = "st,stm32h7-dfsdm-dai";
 309           #sound-dai-cells = <0>;
 310           io-channels = <&dfsdm0 0>;
 311         };
 312       };
 313
 314       dfsdm_pdm1: filter@1 {
 315         compatible = "st,stm32-dfsdm-adc";
 316         reg = <1>;
 317         interrupts = <GIC_SPI 111 IRQ_TYPE_LEVEL_HIGH>;
 318         dmas = <&dmamux1 102 0x400 0x01>;
 319         dma-names = "rx";
 320         #io-channel-cells = <1>;
 321         st,adc-channels = <2 3>;
 322         st,adc-channel-names = "in2", "in3";
 323         st,adc-channel-types = "SPI_R", "SPI_R";
 324         st,adc-channel-clk-src = "CLKOUT_F", "CLKOUT_F";
 325         io-channels = <&sd_adc2 &sd_adc3>;
 326         st,filter-order = <1>;
 327       };
 328     };
 329
 330 ...