On Thu, 7 Jul 2022 08:31:26 +0000 Ibrahim Tilki <Ibrahim.Tilki@xxxxxxxxxx> wrote: > Adding devicetree binding documentation for max11410 adc. > > Signed-off-by: Ibrahim Tilki <Ibrahim.Tilki@xxxxxxxxxx> > Reviewed-by: Nurettin Bolucu <Nurettin.Bolucu@xxxxxxxxxx> Hi. A few questions inline. Mostly stuff I couldn't figure out from a quick scan through the datasheet. > --- > .../bindings/iio/adc/adi,max11410.yaml | 168 ++++++++++++++++++ > 1 file changed, 168 insertions(+) > create mode 100644 Documentation/devicetree/bindings/iio/adc/adi,max11410.yaml > > diff --git a/Documentation/devicetree/bindings/iio/adc/adi,max11410.yaml b/Documentation/devicetree/bindings/iio/adc/adi,max11410.yaml > new file mode 100644 > index 000000000..f28d29fb2 > --- /dev/null > +++ b/Documentation/devicetree/bindings/iio/adc/adi,max11410.yaml > @@ -0,0 +1,168 @@ > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) > +# Copyright 2022 Analog Devices Inc. > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/iio/adc/adi,max11410.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Analog Devices MAX11410 ADC device driver > + > +maintainers: > + - Ibrahim Tilki <ibrahim.tilki@xxxxxxxxxx> > + > +description: | > + Bindings for the Analog Devices MAX11410 ADC device. Datasheet can be > + found here: > + https://datasheets.maximintegrated.com/en/ds/MAX11410.pdf > + > +properties: > + compatible: > + enum: > + - adi,max11410 > + > + reg: > + description: SPI chip select number for the device Description not needed as same for all SPI devices. > + maxItems: 1 > + > + interrupts: > + description: IRQ line for the ADC The description doesn't tell us anything so drop it. There is no need to provide description lines for self documenting items like this. > + maxItems: 1 > + > + '#address-cells': > + const: 1 > + > + '#size-cells': > + const: 0 > + > + avdd-supply: > + description: avdd supply can be used as reference for conversion. Mention it's also a necessary power supply. As mentioned in driver review I'd suggest you actually treat this as 'no explicit reference supplied'. That simplifies the meaning of the adi,reference below. > + > + vref0p-supply: > + description: vref0p supply can be used as reference for conversion. > + > + vref1p-supply: > + description: vref1p supply can be used as reference for conversion. > + > + vref2p-supply: > + description: vref2p supply can be used as reference for conversion. > + > + vref0n-supply: > + description: vref0n supply can be used as reference for conversion. > + > + vref1n-supply: > + description: vref1n supply can be used as reference for conversion. > + > + vref2n-supply: > + description: vref2n supply can be used as reference for conversion. > + > + spi-max-frequency: > + maximum: 8000000 > + > +required: > + - compatible > + - reg > + - avdd-supply > + > +patternProperties: > + "^channel(@[0-9a-f]+)?$": > + $ref: "adc.yaml" > + type: object > + description: Represents the external channels which are connected to the ADC. > + > + properties: > + reg: > + description: The channel number in single-ended mode. > + minimum: 0 > + maximum: 10 > + > + adi,reference: > + description: | > + Select the reference source to use when converting on > + the specific channel. Valid values are: > + 0: REF0P/REF0N VREF0P etc to match namign above. > + 1: REF1P/REF1N > + 2: REF2P/REF2N > + 3: AVDD/AGND > + 4: REF0P/AGND > + 5: REF1P/AGND > + 6: REF2P/AGND Is it valid to use REF0P/AGND for a differential channel? If not I would reduce this list to 0-2 only. If it is valid (so actually useful to do so) then we are stuck with this. That does make me wonder if there is a difference between 3 and 7? If not, just don't list 7 > + 7: AVDD/AGND > + If this field is left empty, AVDD/AGND is selected. > + $ref: /schemas/types.yaml#/definitions/uint32 > + enum: [0, 1, 2, 3, 4, 5, 6, 7] > + default: 7 > + > + adi,input-mode: > + description: | > + Select signal path of input channels. When PGA path is selected, > + hardwaregain property is enabled for channel. Valid values are: > + 0: Buffered, low-power, unity-gain path (default) > + 1: Bypass path > + 2: PGA path > + $ref: /schemas/types.yaml#/definitions/uint32 > + enum: [0, 1, 2] > + default: 0 > + > + diff-channels: true > + > + bipolar: true > + > + settling-time-us: true > + > + adi,buffered-vrefp: > + description: Enable buffered mode for positive reference. > + type: boolean > + > + adi,buffered-vrefn: > + description: Enable buffered mode for negative reference. > + type: boolean > + > + required: > + - reg > + > + additionalProperties: false > + > +additionalProperties: false > + > +examples: > + - | > + spi { > + #address-cells = <1>; > + #size-cells = <0>; > + > + adc@0 { > + compatible = "adi,max11410"; > + reg = <0>; > + spi-max-frequency = <8000000>; > + interrupts = <25 2>; > + interrupt-parent = <&gpio>; > + > + avdd-supply = <&adc_avdd>; > + > + vref1p-supply = <&adc_vref1p>; > + vref1n-supply = <&adc_vref1n>; > + > + #address-cells = <1>; > + #size-cells = <0>; > + > + channel@0 { > + reg = <0>; > + }; > + > + channel@1 { > + reg = <1>; > + diff-channels = <2 3>; > + adi,reference = <1>; > + bipolar; > + settling-time-us = <100000>; > + }; > + > + channel@2 { > + reg = <2>; > + diff-channels = <7 9>; > + adi,reference = <5>; > + adi,input-mode = <2>; > + settling-time-us = <50000>; > + }; > + }; > + };
