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     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
  64 required:
  65   - compatible
  66   - reg
  67   - clocks
  68   - clock-names
  69   - "#address-cells"
  70   - "#size-cells"
  71
  72 additionalProperties: false
  73
  74 patternProperties:
  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
 106       st,filter-order:
 107         description: |
 108           SinC filter order from 0 to 5.
 109           - 0: FastSinC
 110           - [1-5]: order 1 to 5.
 111           For audio purpose it is recommended to use order 3 to 5.
 112         $ref: /schemas/types.yaml#/definitions/uint32
 113         items:
 114           minimum: 0
 115           maximum: 5
 116
 117       "#io-channel-cells":
 118         const: 1
 119
 120       st,adc-channel-types:
 121         description: |
 122           Single-ended channel input type.
 123           - "SPI_R": SPI with data on rising edge (default)
 124           - "SPI_F": SPI with data on falling edge
 125           - "MANCH_R": manchester codec, rising edge = logic 0, falling edge = logic 1
 126           - "MANCH_F": manchester codec, rising edge = logic 1, falling edge = logic 0
 127         items:
 128           enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
 129         $ref: /schemas/types.yaml#/definitions/non-unique-string-array
 130
 131       st,adc-channel-clk-src:
 132         description: |
 133           Conversion clock source.
 134           - "CLKIN": external SPI clock (CLKIN x)
 135           - "CLKOUT": internal SPI clock (CLKOUT) (default)
 136           - "CLKOUT_F": internal SPI clock divided by 2 (falling edge).
 137           - "CLKOUT_R": internal SPI clock divided by 2 (rising edge).
 138         items:
 139           enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
 140         $ref: /schemas/types.yaml#/definitions/non-unique-string-array
 141
 142       st,adc-alt-channel:
 143         description:
 144           Must be defined if two sigma delta modulators are
 145           connected on same SPI input.
 146           If not set, channel n is connected to SPI input n.
 147           If set, channel n is connected to SPI input n + 1.
 148         type: boolean
 149
 150       st,filter0-sync:
 151         description:
 152           Set to 1 to synchronize with DFSDM filter instance 0.
 153           Used for multi microphones synchronization.
 154         type: boolean
 155
 156       dmas:
 157         maxItems: 1
 158
 159       dma-names:
 160         items:
 161           - const: rx
 162
 163     required:
 164       - compatible
 165       - reg
 166       - interrupts
 167       - st,adc-channels
 168       - st,adc-channel-names
 169       - st,filter-order
 170       - "#io-channel-cells"
 171
 172     allOf:
 173       - if:
 174           properties:
 175             compatible:
 176               contains:
 177                 const: st,stm32-dfsdm-adc
 178
 179       - then:
 180           properties:
 181             st,adc-channels:
 182               minItems: 1
 183               maxItems: 8
 184
 185             st,adc-channel-names:
 186               minItems: 1
 187               maxItems: 8
 188
 189             st,adc-channel-types:
 190               minItems: 1
 191               maxItems: 8
 192
 193             st,adc-channel-clk-src:
 194               minItems: 1
 195               maxItems: 8
 196
 197             io-channels:
 198               description:
 199                 From common IIO binding. Used to pipe external sigma delta
 200                 modulator or internal ADC output to DFSDM channel.
 201
 202           required:
 203             - io-channels
 204
 205       - if:
 206           properties:
 207             compatible:
 208               contains:
 209                 const: st,stm32-dfsdm-dmic
 210
 211       - then:
 212           properties:
 213             st,adc-channels:
 214               maxItems: 1
 215
 216             st,adc-channel-names:
 217               maxItems: 1
 218
 219             st,adc-channel-types:
 220               maxItems: 1
 221
 222             st,adc-channel-clk-src:
 223               maxItems: 1
 224
 225           required:
 226             - dmas
 227             - dma-names
 228
 229           patternProperties:
 230             "^dfsdm-dai+$":
 231               type: object
 232               description: child node
 233
 234               properties:
 235                 compatible:
 236                   enum:
 237                     - st,stm32h7-dfsdm-dai
 238
 239                 "#sound-dai-cells":
 240                   const: 0
 241
 242                 io-channels:
 243                   description:
 244                     From common IIO binding. Used to pipe external sigma delta
 245                     modulator or internal ADC output to DFSDM channel.
 246
 247               required:
 248                 - compatible
 249                 - "#sound-dai-cells"
 250                 - io-channels
 251
 252 allOf:
 253   - if:
 254       properties:
 255         compatible:
 256           contains:
 257             const: st,stm32h7-dfsdm
 258
 259   - then:
 260       patternProperties:
 261         "^filter@[0-9]+$":
 262           properties:
 263             reg:
 264               items:
 265                 minimum: 0
 266                 maximum: 3
 267
 268   - if:
 269       properties:
 270         compatible:
 271           contains:
 272             const: st,stm32mp1-dfsdm
 273
 274   - then:
 275       patternProperties:
 276         "^filter@[0-9]+$":
 277           properties:
 278             reg:
 279               items:
 280                 minimum: 0
 281                 maximum: 5
 282
 283 examples:
 284   - |
 285     #include <dt-bindings/interrupt-controller/arm-gic.h>
 286     #include <dt-bindings/clock/stm32mp1-clks.h>
 287     dfsdm: dfsdm@4400d000 {
 288       compatible = "st,stm32mp1-dfsdm";
 289       reg = <0x4400d000 0x800>;
 290       clocks = <&rcc DFSDM_K>, <&rcc ADFSDM_K>;
 291       clock-names = "dfsdm", "audio";
 292       #address-cells = <1>;
 293       #size-cells = <0>;
 294
 295       dfsdm0: filter@0 {
 296         compatible = "st,stm32-dfsdm-dmic";
 297         reg = <0>;
 298         interrupts = <GIC_SPI 110 IRQ_TYPE_LEVEL_HIGH>;
 299         dmas = <&dmamux1 101 0x400 0x01>;
 300         dma-names = "rx";
 301         #io-channel-cells = <1>;
 302         st,adc-channels = <1>;
 303         st,adc-channel-names = "dmic0";
 304         st,adc-channel-types = "SPI_R";
 305         st,adc-channel-clk-src = "CLKOUT";
 306         st,filter-order = <5>;
 307
 308         asoc_pdm0: dfsdm-dai {
 309           compatible = "st,stm32h7-dfsdm-dai";
 310           #sound-dai-cells = <0>;
 311           io-channels = <&dfsdm0 0>;
 312         };
 313       };
 314
 315       dfsdm_pdm1: filter@1 {
 316         compatible = "st,stm32-dfsdm-adc";
 317         reg = <1>;
 318         interrupts = <GIC_SPI 111 IRQ_TYPE_LEVEL_HIGH>;
 319         dmas = <&dmamux1 102 0x400 0x01>;
 320         dma-names = "rx";
 321         #io-channel-cells = <1>;
 322         st,adc-channels = <2 3>;
 323         st,adc-channel-names = "in2", "in3";
 324         st,adc-channel-types = "SPI_R", "SPI_R";
 325         st,adc-channel-clk-src = "CLKOUT_F", "CLKOUT_F";
 326         io-channels = <&sd_adc2 &sd_adc3>;
 327         st,filter-order = <1>;
 328       };
 329     };
 330
 331 ...