# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) %YAML 1.2 --- $id: http://devicetree.org/schemas/iio/adc/st,stm32-adc.yaml# $schema: http://devicetree.org/meta-schemas/core.yaml# title: STMicroelectronics STM32 ADC description: | STM32 ADC is a successive approximation analog-to-digital converter. It has several multiplexed input channels. Conversions can be performed in single, continuous, scan or discontinuous mode. Result of the ADC is stored in a left-aligned or right-aligned 32-bit data register. Conversions can be launched in software or using hardware triggers. The analog watchdog feature allows the application to detect if the input voltage goes beyond the user-defined, higher or lower thresholds. Each STM32 ADC block can have up to 3 ADC instances. maintainers: - Fabrice Gasnier properties: compatible: enum: - st,stm32f4-adc-core - st,stm32h7-adc-core - st,stm32mp1-adc-core - st,stm32mp13-adc-core reg: maxItems: 1 interrupts: description: | One or more interrupts for ADC block, depending on part used: - stm32f4 and stm32h7 share a common ADC interrupt line. - stm32mp1 has two separate interrupt lines, one for each ADC within ADC block. - stm32mp13 has an interrupt line per ADC block. minItems: 1 maxItems: 2 clocks: minItems: 1 maxItems: 2 description: | Core can use up to two clocks, depending on part used: - "adc" clock: for the analog circuitry, common to all ADCs. It's required on stm32f4. It's optional on stm32h7 and stm32mp1. - "bus" clock: for registers access, common to all ADCs. It's not present on stm32f4. It's required on stm32h7 and stm32mp1. clock-names: true st,max-clk-rate-hz: description: Allow to specify desired max clock rate used by analog circuitry. vdda-supply: description: Phandle to the vdda input analog voltage. vref-supply: description: Phandle to the vref input analog reference voltage. booster-supply: description: Phandle to the embedded booster regulator that can be used to supply ADC analog input switches on stm32h7 and stm32mp1. vdd-supply: description: Phandle to the vdd input voltage. It can be used to supply ADC analog input switches on stm32mp1. st,syscfg: description: Phandle to system configuration controller. It can be used to control the analog circuitry on stm32mp1. $ref: /schemas/types.yaml#/definitions/phandle-array interrupt-controller: true '#interrupt-cells': const: 1 '#address-cells': const: 1 '#size-cells': const: 0 allOf: - if: properties: compatible: contains: const: st,stm32f4-adc-core then: properties: clocks: maxItems: 1 clock-names: const: adc interrupts: items: - description: interrupt line common for all ADCs st,max-clk-rate-hz: minimum: 600000 maximum: 36000000 default: 36000000 booster-supply: false vdd-supply: false st,syscfg: false - if: properties: compatible: contains: const: st,stm32h7-adc-core then: properties: clocks: minItems: 1 maxItems: 2 clock-names: items: - const: bus - const: adc minItems: 1 interrupts: items: - description: interrupt line common for all ADCs st,max-clk-rate-hz: minimum: 120000 maximum: 36000000 default: 36000000 vdd-supply: false st,syscfg: false - if: properties: compatible: contains: const: st,stm32mp1-adc-core then: properties: clocks: minItems: 1 maxItems: 2 clock-names: items: - const: bus - const: adc minItems: 1 interrupts: items: - description: interrupt line for ADC1 - description: interrupt line for ADC2 st,max-clk-rate-hz: minimum: 120000 maximum: 36000000 default: 36000000 - if: properties: compatible: contains: const: st,stm32mp13-adc-core then: properties: clocks: minItems: 1 maxItems: 2 clock-names: items: - const: bus - const: adc minItems: 1 interrupts: items: - description: ADC interrupt line st,max-clk-rate-hz: minimum: 150000 maximum: 75000000 default: 75000000 additionalProperties: false required: - compatible - reg - interrupts - clocks - clock-names - vdda-supply - vref-supply - interrupt-controller - '#interrupt-cells' - '#address-cells' - '#size-cells' patternProperties: "^adc@[0-9]+$": type: object description: An ADC block node should contain at least one subnode, representing an ADC instance available on the machine. properties: compatible: enum: - st,stm32f4-adc - st,stm32h7-adc - st,stm32mp1-adc - st,stm32mp13-adc reg: description: | Offset of ADC instance in ADC block. Valid values are: - 0x0: ADC1 - 0x100: ADC2 - 0x200: ADC3 (stm32f4 only) maxItems: 1 '#io-channel-cells': const: 1 '#address-cells': const: 1 '#size-cells': const: 0 interrupts: description: | IRQ Line for the ADC instance. Valid values are: - 0 for adc@0 (single adc for stm32mp13) - 1 for adc@100 - 2 for adc@200 (stm32f4 only) maxItems: 1 clocks: description: Input clock private to this ADC instance. It's required only on stm32f4, that has per instance clock input for registers access. maxItems: 1 dmas: description: RX DMA Channel maxItems: 1 dma-names: const: rx assigned-resolution-bits: description: | Resolution (bits) to use for conversions: - can be 6, 8, 10 or 12 on stm32f4 and stm32mp13 - can be 8, 10, 12, 14 or 16 on stm32h7 and stm32mp1 st,adc-channels: description: | List of single-ended channels muxed for this ADC. It can have up to: - 16 channels, numbered from 0 to 15 (for in0..in15) on stm32f4 - 19 channels, numbered from 0 to 18 (for in0..in18) on stm32mp13. - 20 channels, numbered from 0 to 19 (for in0..in19) on stm32h7 and stm32mp1. $ref: /schemas/types.yaml#/definitions/uint32-array deprecated: true st,adc-diff-channels: description: | List of differential channels muxed for this ADC. Some channels can be configured as differential instead of single-ended on stm32h7 and on stm32mp1. Positive and negative inputs pairs are listed: , ,... vinp and vinn are numbered from 0 to 19. Note: At least one of "st,adc-channels" or "st,adc-diff-channels" is required if no adc generic channel is defined. These legacy channel properties are exclusive with adc generic channel bindings. Both properties can be used together. Some channels can be used as single-ended and some other ones as differential (mixed). But channels can't be configured both as single-ended and differential. $ref: /schemas/types.yaml#/definitions/uint32-matrix items: items: - description: | "vinp" indicates positive input number minimum: 0 maximum: 19 - description: | "vinn" indicates negative input number minimum: 0 maximum: 19 deprecated: true st,min-sample-time-nsecs: description: Minimum sampling time in nanoseconds. Depending on hardware (board) e.g. high/low analog input source impedance, fine tune of ADC sampling time may be recommended. This can be either one value or an array that matches "st,adc-channels" and/or "st,adc-diff-channels" list, to set sample time resp. for all channels, or independently for each channel. $ref: /schemas/types.yaml#/definitions/uint32-array deprecated: true nvmem-cells: items: - description: Phandle to the calibration vrefint data provided by otp nvmem-cell-names: items: - const: vrefint patternProperties: "^channel@([0-9]|1[0-9])$": type: object $ref: adc.yaml description: Represents the external channels which are connected to the ADC. properties: reg: items: minimum: 0 maximum: 19 label: description: | Unique name to identify which channel this is. Reserved label names "vddcore", "vddcpu", "vddq_ddr", "vrefint" and "vbat" are used to identify internal channels with matching names. diff-channels: $ref: /schemas/types.yaml#/definitions/uint32-array items: minimum: 0 maximum: 19 st,min-sample-time-ns: description: | Minimum sampling time in nanoseconds. Depending on hardware (board) e.g. high/low analog input source impedance, fine tune of ADC sampling time may be recommended. required: - reg additionalProperties: false allOf: - if: properties: compatible: contains: const: st,stm32f4-adc then: properties: reg: enum: - 0x0 - 0x100 - 0x200 interrupts: minimum: 0 maximum: 2 assigned-resolution-bits: enum: [6, 8, 10, 12] default: 12 st,adc-channels: minItems: 1 maxItems: 16 items: minimum: 0 maximum: 15 st,adc-diff-channels: false st,min-sample-time-nsecs: minItems: 1 maxItems: 16 items: minimum: 80 required: - clocks - if: properties: compatible: contains: enum: - st,stm32h7-adc - st,stm32mp1-adc then: properties: reg: enum: - 0x0 - 0x100 interrupts: minimum: 0 maximum: 1 assigned-resolution-bits: enum: [8, 10, 12, 14, 16] default: 16 st,adc-channels: minItems: 1 maxItems: 20 items: minimum: 0 maximum: 19 st,min-sample-time-nsecs: minItems: 1 maxItems: 20 items: minimum: 40 - if: properties: compatible: contains: const: st,stm32mp13-adc then: properties: reg: const: 0x0 interrupts: const: 0 assigned-resolution-bits: enum: [6, 8, 10, 12] default: 12 st,adc-channels: minItems: 1 maxItems: 19 items: minimum: 0 maximum: 18 st,min-sample-time-nsecs: minItems: 1 maxItems: 19 items: minimum: 40 additionalProperties: false required: - compatible - reg - interrupts - '#io-channel-cells' examples: - | // Example 1: with stm32f429, ADC1, single-ended channel 8 adc123: adc@40012000 { compatible = "st,stm32f4-adc-core"; reg = <0x40012000 0x400>; interrupts = <18>; clocks = <&rcc 0 168>; clock-names = "adc"; st,max-clk-rate-hz = <36000000>; vdda-supply = <&vdda>; vref-supply = <&vref>; interrupt-controller; #interrupt-cells = <1>; #address-cells = <1>; #size-cells = <0>; adc@0 { compatible = "st,stm32f4-adc"; #io-channel-cells = <1>; reg = <0x0>; clocks = <&rcc 0 168>; interrupt-parent = <&adc123>; interrupts = <0>; st,adc-channels = <8>; dmas = <&dma2 0 0 0x400 0x0>; dma-names = "rx"; assigned-resolution-bits = <8>; }; // ... // other adc child nodes follow... }; - | // Example 2: with stm32mp157c to setup ADC1 with: // - channels 0 & 1 as single-ended // - channels 2 & 3 as differential (with resp. 6 & 7 negative inputs) #include #include adc12: adc@48003000 { compatible = "st,stm32mp1-adc-core"; reg = <0x48003000 0x400>; interrupts = , ; clocks = <&rcc ADC12>, <&rcc ADC12_K>; clock-names = "bus", "adc"; booster-supply = <&booster>; vdd-supply = <&vdd>; vdda-supply = <&vdda>; vref-supply = <&vref>; st,syscfg = <&syscfg>; interrupt-controller; #interrupt-cells = <1>; #address-cells = <1>; #size-cells = <0>; adc@0 { compatible = "st,stm32mp1-adc"; #io-channel-cells = <1>; reg = <0x0>; interrupt-parent = <&adc12>; interrupts = <0>; st,adc-channels = <0 1>; st,adc-diff-channels = <2 6>, <3 7>; st,min-sample-time-nsecs = <5000>; dmas = <&dmamux1 9 0x400 0x05>; dma-names = "rx"; }; // ... // other adc child node follow... }; - | // Example 3: with stm32mp157c to setup ADC2 with: // - internal channels 13, 14, 15. #include #include adc122: adc@48003000 { compatible = "st,stm32mp1-adc-core"; reg = <0x48003000 0x400>; interrupts = , ; clocks = <&rcc ADC12>, <&rcc ADC12_K>; clock-names = "bus", "adc"; booster-supply = <&booster>; vdd-supply = <&vdd>; vdda-supply = <&vdda>; vref-supply = <&vref>; st,syscfg = <&syscfg>; interrupt-controller; #interrupt-cells = <1>; #address-cells = <1>; #size-cells = <0>; adc@100 { compatible = "st,stm32mp1-adc"; #io-channel-cells = <1>; reg = <0x100>; interrupts = <1>; #address-cells = <1>; #size-cells = <0>; channel@13 { reg = <13>; label = "vrefint"; st,min-sample-time-ns = <9000>; }; channel@14 { reg = <14>; label = "vddcore"; st,min-sample-time-ns = <9000>; }; channel@15 { reg = <15>; label = "vbat"; st,min-sample-time-ns = <9000>; }; }; }; ...