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         allOf:
  99           - $ref: /schemas/types.yaml#/definitions/uint32-array
 100           - items:
 101               minimum: 0
 102               maximum: 7
 103
 104       st,adc-channel-names:
 105         description: List of single-ended channel names.
 106         allOf:
 107           - $ref: /schemas/types.yaml#/definitions/string-array
 108
 109       st,filter-order:
 110         description: |
 111           SinC filter order from 0 to 5.
 112           - 0: FastSinC
 113           - [1-5]: order 1 to 5.
 114           For audio purpose it is recommended to use order 3 to 5.
 115         allOf:
 116           - $ref: /schemas/types.yaml#/definitions/uint32
 117           - items:
 118               minimum: 0
 119               maximum: 5
 120
 121       "#io-channel-cells":
 122         const: 1
 123
 124       st,adc-channel-types:
 125         description: |
 126           Single-ended channel input type.
 127           - "SPI_R": SPI with data on rising edge (default)
 128           - "SPI_F": SPI with data on falling edge
 129           - "MANCH_R": manchester codec, rising edge = logic 0, falling edge = logic 1
 130           - "MANCH_F": manchester codec, rising edge = logic 1, falling edge = logic 0
 131         items:
 132           enum: [ SPI_R, SPI_F, MANCH_R, MANCH_F ]
 133         allOf:
 134           - $ref: /schemas/types.yaml#/definitions/non-unique-string-array
 135
 136       st,adc-channel-clk-src:
 137         description: |
 138           Conversion clock source.
 139           - "CLKIN": external SPI clock (CLKIN x)
 140           - "CLKOUT": internal SPI clock (CLKOUT) (default)
 141           - "CLKOUT_F": internal SPI clock divided by 2 (falling edge).
 142           - "CLKOUT_R": internal SPI clock divided by 2 (rising edge).
 143         items:
 144           enum: [ CLKIN, CLKOUT, CLKOUT_F, CLKOUT_R ]
 145         allOf:
 146           - $ref: /schemas/types.yaml#/definitions/non-unique-string-array
 147
 148       st,adc-alt-channel:
 149         description:
 150           Must be defined if two sigma delta modulators are
 151           connected on same SPI input.
 152           If not set, channel n is connected to SPI input n.
 153           If set, channel n is connected to SPI input n + 1.
 154         type: boolean
 155
 156       st,filter0-sync:
 157         description:
 158           Set to 1 to synchronize with DFSDM filter instance 0.
 159           Used for multi microphones synchronization.
 160         type: boolean
 161
 162       dmas:
 163         maxItems: 1
 164
 165       dma-names:
 166         items:
 167           - const: rx
 168
 169     required:
 170       - compatible
 171       - reg
 172       - interrupts
 173       - st,adc-channels
 174       - st,adc-channel-names
 175       - st,filter-order
 176       - "#io-channel-cells"
 177
 178     allOf:
 179       - if:
 180           properties:
 181             compatible:
 182               contains:
 183                 const: st,stm32-dfsdm-adc
 184
 185       - then:
 186           properties:
 187             st,adc-channels:
 188               minItems: 1
 189               maxItems: 8
 190
 191             st,adc-channel-names:
 192               minItems: 1
 193               maxItems: 8
 194
 195             st,adc-channel-types:
 196               minItems: 1
 197               maxItems: 8
 198
 199             st,adc-channel-clk-src:
 200               minItems: 1
 201               maxItems: 8
 202
 203             io-channels:
 204               description:
 205                 From common IIO binding. Used to pipe external sigma delta
 206                 modulator or internal ADC output to DFSDM channel.
 207                 This is not required for "st,stm32-dfsdm-pdm" compatibility as
 208                 PDM microphone is binded in Audio DT node.
 209
 210           required:
 211             - io-channels
 212
 213       - if:
 214           properties:
 215             compatible:
 216               contains:
 217                 const: st,stm32-dfsdm-dmic
 218
 219       - then:
 220           properties:
 221             st,adc-channels:
 222               maxItems: 1
 223
 224             st,adc-channel-names:
 225               maxItems: 1
 226
 227             st,adc-channel-types:
 228               maxItems: 1
 229
 230             st,adc-channel-clk-src:
 231               maxItems: 1
 232
 233           required:
 234             - dmas
 235             - dma-names
 236
 237           patternProperties:
 238             "^dfsdm-dai+$":
 239               type: object
 240               description: child node
 241
 242               properties:
 243                 "#sound-dai-cells":
 244                   const: 0
 245
 246                 io-channels:
 247                   description:
 248                     From common IIO binding. Used to pipe external sigma delta
 249                     modulator or internal ADC output to DFSDM channel.
 250
 251               required:
 252                 - "#sound-dai-cells"
 253                 - io-channels
 254
 255 allOf:
 256   - if:
 257       properties:
 258         compatible:
 259           contains:
 260             const: st,stm32h7-dfsdm
 261
 262   - then:
 263       patternProperties:
 264         "^filter@[0-9]+$":
 265           properties:
 266             reg:
 267               items:
 268                 minimum: 0
 269                 maximum: 3
 270
 271   - if:
 272       properties:
 273         compatible:
 274           contains:
 275             const: st,stm32mp1-dfsdm
 276
 277   - then:
 278       patternProperties:
 279         "^filter@[0-9]+$":
 280           properties:
 281             reg:
 282               items:
 283                 minimum: 0
 284                 maximum: 5
 285
 286 examples:
 287   - |
 288     #include <dt-bindings/interrupt-controller/arm-gic.h>
 289     #include <dt-bindings/clock/stm32mp1-clks.h>
 290     dfsdm: dfsdm@4400d000 {
 291       compatible = "st,stm32mp1-dfsdm";
 292       reg = <0x4400d000 0x800>;
 293       clocks = <&rcc DFSDM_K>, <&rcc ADFSDM_K>;
 294       clock-names = "dfsdm", "audio";
 295       #address-cells = <1>;
 296       #size-cells = <0>;
 297
 298       dfsdm0: filter@0 {
 299         compatible = "st,stm32-dfsdm-dmic";
 300         reg = <0>;
 301         interrupts = <GIC_SPI 110 IRQ_TYPE_LEVEL_HIGH>;
 302         dmas = <&dmamux1 101 0x400 0x01>;
 303         dma-names = "rx";
 304         #io-channel-cells = <1>;
 305         st,adc-channels = <1>;
 306         st,adc-channel-names = "dmic0";
 307         st,adc-channel-types = "SPI_R";
 308         st,adc-channel-clk-src = "CLKOUT";
 309         st,filter-order = <5>;
 310
 311         asoc_pdm0: dfsdm-dai {
 312           compatible = "st,stm32h7-dfsdm-dai";
 313           #sound-dai-cells = <0>;
 314           io-channels = <&dfsdm0 0>;
 315         };
 316       };
 317
 318       dfsdm_pdm1: filter@1 {
 319         compatible = "st,stm32-dfsdm-adc";
 320         reg = <1>;
 321         interrupts = <GIC_SPI 111 IRQ_TYPE_LEVEL_HIGH>;
 322         dmas = <&dmamux1 102 0x400 0x01>;
 323         dma-names = "rx";
 324         #io-channel-cells = <1>;
 325         st,adc-channels = <2 3>;
 326         st,adc-channel-names = "in2", "in3";
 327         st,adc-channel-types = "SPI_R", "SPI_R";
 328         st,adc-channel-clk-src = "CLKOUT_F", "CLKOUT_F";
 329         io-channels = <&sd_adc2 &sd_adc3>;
 330         st,filter-order = <1>;
 331       };
 332     };
 333
 334 ...