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 7title: STMicroelectronics STM32 DFSDM ADC device driver 8 9maintainers: 10 - Fabrice Gasnier <fabrice.gasnier@st.com> 11 - Olivier Moysan <olivier.moysan@st.com> 12 13description: | 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 25properties: 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 64required: 65 - compatible 66 - reg 67 - clocks 68 - clock-names 69 - "#address-cells" 70 - "#size-cells" 71 72additionalProperties: false 73 74patternProperties: 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 255allOf: 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 286examples: 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... 335