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
 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         items:
 112           minimum: 0
 113           maximum: 5
 114
 115       "#io-channel-cells":
 116         const: 1
 117
 118       st,adc-channel-types:
 119         description: |
 120           Single-ended channel input type.
 121           - "SPI_R": SPI with data on rising edge (default)
 122           - "SPI_F": SPI with data on falling edge
 123           - "MANCH_R": manchester codec, rising edge = logic 0, falling edge = logic 1
 124           - "MANCH_F": manchester codec, rising edge = logic 1, falling edge = logic 0
 125         items:
 126           enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
 127         $ref: /schemas/types.yaml#/definitions/non-unique-string-array
 128
 129       st,adc-channel-clk-src:
 130         description: |
 131           Conversion clock source.
 132           - "CLKIN": external SPI clock (CLKIN x)
 133           - "CLKOUT": internal SPI clock (CLKOUT) (default)
 134           - "CLKOUT_F": internal SPI clock divided by 2 (falling edge).
 135           - "CLKOUT_R": internal SPI clock divided by 2 (rising edge).
 136         items:
 137           enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
 138         $ref: /schemas/types.yaml#/definitions/non-unique-string-array
 139
 140       st,adc-alt-channel:
 141         description:
 142           Must be defined if two sigma delta modulators are
 143           connected on same SPI input.
 144           If not set, channel n is connected to SPI input n.
 145           If set, channel n is connected to SPI input n + 1.
 146         type: boolean
 147
 148       st,filter0-sync:
 149         description:
 150           Set to 1 to synchronize with DFSDM filter instance 0.
 151           Used for multi microphones synchronization.
 152         type: boolean
 153
 154       dmas:
 155         maxItems: 1
 156
 157       dma-names:
 158         items:
 159           - const: rx
 160
 161     required:
 162       - compatible
 163       - reg
 164       - interrupts
 165       - st,adc-channels
 166       - st,adc-channel-names
 167       - st,filter-order
 168       - "#io-channel-cells"
 169
 170     allOf:
 171       - if:
 172           properties:
 173             compatible:
 174               contains:
 175                 const: st,stm32-dfsdm-adc
 176
 177       - then:
 178           properties:
 179             st,adc-channels:
 180               minItems: 1
 181               maxItems: 8
 182
 183             st,adc-channel-names:
 184               minItems: 1
 185               maxItems: 8
 186
 187             st,adc-channel-types:
 188               minItems: 1
 189               maxItems: 8
 190
 191             st,adc-channel-clk-src:
 192               minItems: 1
 193               maxItems: 8
 194
 195             io-channels:
 196               description:
 197                 From common IIO binding. Used to pipe external sigma delta
 198                 modulator or internal ADC output to DFSDM channel.
 199
 200           required:
 201             - io-channels
 202
 203       - if:
 204           properties:
 205             compatible:
 206               contains:
 207                 const: st,stm32-dfsdm-dmic
 208
 209       - then:
 210           properties:
 211             st,adc-channels:
 212               maxItems: 1
 213
 214             st,adc-channel-names:
 215               maxItems: 1
 216
 217             st,adc-channel-types:
 218               maxItems: 1
 219
 220             st,adc-channel-clk-src:
 221               maxItems: 1
 222
 223           required:
 224             - dmas
 225             - dma-names
 226
 227           patternProperties:
 228             "^dfsdm-dai+$":
 229               type: object
 230               description: child node
 231
 232               properties:
 233                 compatible:
 234                   enum:
 235                     - st,stm32h7-dfsdm-dai
 236
 237                 "#sound-dai-cells":
 238                   const: 0
 239
 240                 io-channels:
 241                   description:
 242                     From common IIO binding. Used to pipe external sigma delta
 243                     modulator or internal ADC output to DFSDM channel.
 244
 245               required:
 246                 - compatible
 247                 - "#sound-dai-cells"
 248                 - io-channels
 249
 250 allOf:
 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
 281 examples:
 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 ...