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         $ref: /schemas/types.yaml#/definitions/string-array
 106
 107       st,filter-order:
 108         description: |
 109           SinC filter order from 0 to 5.
 110           - 0: FastSinC
 111           - [1-5]: order 1 to 5.
 112           For audio purpose it is recommended to use order 3 to 5.
 113         $ref: /schemas/types.yaml#/definitions/uint32
 114         items:
 115           minimum: 0
 116           maximum: 5
 117
 118       "#io-channel-cells":
 119         const: 1
 120
 121       st,adc-channel-types:
 122         description: |
 123           Single-ended channel input type.
 124           - "SPI_R": SPI with data on rising edge (default)
 125           - "SPI_F": SPI with data on falling edge
 126           - "MANCH_R": manchester codec, rising edge = logic 0, falling edge = logic 1
 127           - "MANCH_F": manchester codec, rising edge = logic 1, falling edge = logic 0
 128         items:
 129           enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
 130         $ref: /schemas/types.yaml#/definitions/non-unique-string-array
 131
 132       st,adc-channel-clk-src:
 133         description: |
 134           Conversion clock source.
 135           - "CLKIN": external SPI clock (CLKIN x)
 136           - "CLKOUT": internal SPI clock (CLKOUT) (default)
 137           - "CLKOUT_F": internal SPI clock divided by 2 (falling edge).
 138           - "CLKOUT_R": internal SPI clock divided by 2 (rising edge).
 139         items:
 140           enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
 141         $ref: /schemas/types.yaml#/definitions/non-unique-string-array
 142
 143       st,adc-alt-channel:
 144         description:
 145           Must be defined if two sigma delta modulators are
 146           connected on same SPI input.
 147           If not set, channel n is connected to SPI input n.
 148           If set, channel n is connected to SPI input n + 1.
 149         type: boolean
 150
 151       st,filter0-sync:
 152         description:
 153           Set to 1 to synchronize with DFSDM filter instance 0.
 154           Used for multi microphones synchronization.
 155         type: boolean
 156
 157       dmas:
 158         maxItems: 1
 159
 160       dma-names:
 161         items:
 162           - const: rx
 163
 164     required:
 165       - compatible
 166       - reg
 167       - interrupts
 168       - st,adc-channels
 169       - st,adc-channel-names
 170       - st,filter-order
 171       - "#io-channel-cells"
 172
 173     allOf:
 174       - if:
 175           properties:
 176             compatible:
 177               contains:
 178                 const: st,stm32-dfsdm-adc
 179
 180       - then:
 181           properties:
 182             st,adc-channels:
 183               minItems: 1
 184               maxItems: 8
 185
 186             st,adc-channel-names:
 187               minItems: 1
 188               maxItems: 8
 189
 190             st,adc-channel-types:
 191               minItems: 1
 192               maxItems: 8
 193
 194             st,adc-channel-clk-src:
 195               minItems: 1
 196               maxItems: 8
 197
 198             io-channels:
 199               description:
 200                 From common IIO binding. Used to pipe external sigma delta
 201                 modulator or internal ADC output to DFSDM channel.
 202
 203           required:
 204             - io-channels
 205
 206       - if:
 207           properties:
 208             compatible:
 209               contains:
 210                 const: st,stm32-dfsdm-dmic
 211
 212       - then:
 213           properties:
 214             st,adc-channels:
 215               maxItems: 1
 216
 217             st,adc-channel-names:
 218               maxItems: 1
 219
 220             st,adc-channel-types:
 221               maxItems: 1
 222
 223             st,adc-channel-clk-src:
 224               maxItems: 1
 225
 226           required:
 227             - dmas
 228             - dma-names
 229
 230           patternProperties:
 231             "^dfsdm-dai+$":
 232               type: object
 233               description: child node
 234
 235               properties:
 236                 compatible:
 237                   enum:
 238                     - st,stm32h7-dfsdm-dai
 239
 240                 "#sound-dai-cells":
 241                   const: 0
 242
 243                 io-channels:
 244                   description:
 245                     From common IIO binding. Used to pipe external sigma delta
 246                     modulator or internal ADC output to DFSDM channel.
 247
 248               required:
 249                 - compatible
 250                 - "#sound-dai-cells"
 251                 - io-channels
 252
 253 allOf:
 254   - if:
 255       properties:
 256         compatible:
 257           contains:
 258             const: st,stm32h7-dfsdm
 259
 260   - then:
 261       patternProperties:
 262         "^filter@[0-9]+$":
 263           properties:
 264             reg:
 265               items:
 266                 minimum: 0
 267                 maximum: 3
 268
 269   - if:
 270       properties:
 271         compatible:
 272           contains:
 273             const: st,stm32mp1-dfsdm
 274
 275   - then:
 276       patternProperties:
 277         "^filter@[0-9]+$":
 278           properties:
 279             reg:
 280               items:
 281                 minimum: 0
 282                 maximum: 5
 283
 284 examples:
 285   - |
 286     #include <dt-bindings/interrupt-controller/arm-gic.h>
 287     #include <dt-bindings/clock/stm32mp1-clks.h>
 288     dfsdm: dfsdm@4400d000 {
 289       compatible = "st,stm32mp1-dfsdm";
 290       reg = <0x4400d000 0x800>;
 291       clocks = <&rcc DFSDM_K>, <&rcc ADFSDM_K>;
 292       clock-names = "dfsdm", "audio";
 293       #address-cells = <1>;
 294       #size-cells = <0>;
 295
 296       dfsdm0: filter@0 {
 297         compatible = "st,stm32-dfsdm-dmic";
 298         reg = <0>;
 299         interrupts = <GIC_SPI 110 IRQ_TYPE_LEVEL_HIGH>;
 300         dmas = <&dmamux1 101 0x400 0x01>;
 301         dma-names = "rx";
 302         #io-channel-cells = <1>;
 303         st,adc-channels = <1>;
 304         st,adc-channel-names = "dmic0";
 305         st,adc-channel-types = "SPI_R";
 306         st,adc-channel-clk-src = "CLKOUT";
 307         st,filter-order = <5>;
 308
 309         asoc_pdm0: dfsdm-dai {
 310           compatible = "st,stm32h7-dfsdm-dai";
 311           #sound-dai-cells = <0>;
 312           io-channels = <&dfsdm0 0>;
 313         };
 314       };
 315
 316       dfsdm_pdm1: filter@1 {
 317         compatible = "st,stm32-dfsdm-adc";
 318         reg = <1>;
 319         interrupts = <GIC_SPI 111 IRQ_TYPE_LEVEL_HIGH>;
 320         dmas = <&dmamux1 102 0x400 0x01>;
 321         dma-names = "rx";
 322         #io-channel-cells = <1>;
 323         st,adc-channels = <2 3>;
 324         st,adc-channel-names = "in2", "in3";
 325         st,adc-channel-types = "SPI_R", "SPI_R";
 326         st,adc-channel-clk-src = "CLKOUT_F", "CLKOUT_F";
 327         io-channels = <&sd_adc2 &sd_adc3>;
 328         st,filter-order = <1>;
 329       };
 330     };
 331
 332 ...