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@foss.st.com>
  11   - Olivier Moysan <olivier.moysan@foss.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     unevaluatedProperties: false
  76     description: child node
  77
  78     properties:
  79       compatible:
  80         enum:
  81           - st,stm32-dfsdm-adc
  82           - st,stm32-dfsdm-dmic
  83
  84       reg:
  85         description: Specifies the DFSDM filter instance used.
  86         maxItems: 1
  87
  88       interrupts:
  89         maxItems: 1
  90
  91       st,adc-channels:
  92         description: |
  93           List of single-ended channels muxed for this ADC.
  94           On stm32h7 and stm32mp1:
  95           - For st,stm32-dfsdm-adc: up to 8 channels numbered from 0 to 7.
  96           - For st,stm32-dfsdm-dmic: 1 channel numbered from 0 to 7.
  97         $ref: /schemas/types.yaml#/definitions/uint32-array
  98         items:
  99           minimum: 0
 100           maximum: 7
 101
 102       st,adc-channel-names:
 103         description: List of single-ended channel names.
 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         maximum: 5
 113
 114       "#io-channel-cells":
 115         const: 1
 116
 117       st,adc-channel-types:
 118         description: |
 119           Single-ended channel input type.
 120           - "SPI_R": SPI with data on rising edge (default)
 121           - "SPI_F": SPI with data on falling edge
 122           - "MANCH_R": manchester codec, rising edge = logic 0, falling edge = logic 1
 123           - "MANCH_F": manchester codec, rising edge = logic 1, falling edge = logic 0
 124         items:
 125           enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
 126         $ref: /schemas/types.yaml#/definitions/non-unique-string-array
 127
 128       st,adc-channel-clk-src:
 129         description: |
 130           Conversion clock source.
 131           - "CLKIN": external SPI clock (CLKIN x)
 132           - "CLKOUT": internal SPI clock (CLKOUT) (default)
 133           - "CLKOUT_F": internal SPI clock divided by 2 (falling edge).
 134           - "CLKOUT_R": internal SPI clock divided by 2 (rising edge).
 135         items:
 136           enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
 137         $ref: /schemas/types.yaml#/definitions/non-unique-string-array
 138
 139       st,adc-alt-channel:
 140         description:
 141           Must be defined if two sigma delta modulators are
 142           connected on same SPI input.
 143           If not set, channel n is connected to SPI input n.
 144           If set, channel n is connected to SPI input n + 1.
 145         type: boolean
 146
 147       st,filter0-sync:
 148         description:
 149           Set to 1 to synchronize with DFSDM filter instance 0.
 150           Used for multi microphones synchronization.
 151         type: boolean
 152
 153       dmas:
 154         maxItems: 1
 155
 156       dma-names:
 157         items:
 158           - const: rx
 159
 160     required:
 161       - compatible
 162       - reg
 163       - interrupts
 164       - st,adc-channels
 165       - st,adc-channel-names
 166       - st,filter-order
 167       - "#io-channel-cells"
 168
 169     allOf:
 170       - if:
 171           properties:
 172             compatible:
 173               contains:
 174                 const: st,stm32-dfsdm-adc
 175
 176         then:
 177           properties:
 178             st,adc-channels:
 179               minItems: 1
 180               maxItems: 8
 181
 182             st,adc-channel-names:
 183               minItems: 1
 184               maxItems: 8
 185
 186             st,adc-channel-types:
 187               minItems: 1
 188               maxItems: 8
 189
 190             st,adc-channel-clk-src:
 191               minItems: 1
 192               maxItems: 8
 193
 194             io-channels:
 195               description:
 196                 From common IIO binding. Used to pipe external sigma delta
 197                 modulator or internal ADC output to DFSDM channel.
 198
 199           required:
 200             - io-channels
 201
 202       - if:
 203           properties:
 204             compatible:
 205               contains:
 206                 const: st,stm32-dfsdm-dmic
 207
 208         then:
 209           properties:
 210             st,adc-channels:
 211               maxItems: 1
 212
 213             st,adc-channel-names:
 214               maxItems: 1
 215
 216             st,adc-channel-types:
 217               maxItems: 1
 218
 219             st,adc-channel-clk-src:
 220               maxItems: 1
 221
 222           required:
 223             - dmas
 224             - dma-names
 225
 226           patternProperties:
 227             "^dfsdm-dai+$":
 228               type: object
 229               additionalProperties: false
 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 ...