Message ID | 20230405140114.99011-4-frattaroli.nicolas@gmail.com |
---|---|
State | Changes Requested, archived |
Headers | show |
Series | Add MCP48XX bindings and driver support | expand |
Context | Check | Description |
---|---|---|
robh/checkpatch | success | |
robh/patch-applied | success | |
robh/dtbs-check | warning | build log |
robh/dt-meta-schema | success |
On 05/04/2023 16:01, Nicolas Frattaroli wrote: > The MCP4801, MCP4802, MCP4811, MCP4812, MCP4821, and MCP4822 are > SPI digital-to-analog converters by Microchip, which have an > internal voltage reference, in contrast to the MCP49xx series > of DACs which use an external voltage reference. > > Thus, these need a separate binding, as to not overcomplicate > the mcp4922 binding. The difference is just one property which is very easy to handle - one allOf:if:then: with vref-supply: false Are there any other differences? Best regards, Krzysztof
On Mittwoch, 5. April 2023 16:10:10 CEST Krzysztof Kozlowski wrote: > On 05/04/2023 16:01, Nicolas Frattaroli wrote: > > The MCP4801, MCP4802, MCP4811, MCP4812, MCP4821, and MCP4822 are > > SPI digital-to-analog converters by Microchip, which have an > > internal voltage reference, in contrast to the MCP49xx series > > of DACs which use an external voltage reference. > > > > Thus, these need a separate binding, as to not overcomplicate > > the mcp4922 binding. > > The difference is just one property which is very easy to handle - one > allOf:if:then: with > vref-supply: false > > Are there any other differences? > > Best regards, > Krzysztof > > In place of the external vref input, the MCP48XX series chips also have a "SHDN" input, which is an active-low pin to disable the whole chip and put it in a low power state. Future users of the bindings may want to model this as being tied to some GPIO, though I haven't done it here since I don't care about this feature. Kind regards, Nicolas Frattaroli
On 05/04/2023 16:17, Nicolas Frattaroli wrote: > On Mittwoch, 5. April 2023 16:10:10 CEST Krzysztof Kozlowski wrote: >> On 05/04/2023 16:01, Nicolas Frattaroli wrote: >>> The MCP4801, MCP4802, MCP4811, MCP4812, MCP4821, and MCP4822 are >>> SPI digital-to-analog converters by Microchip, which have an >>> internal voltage reference, in contrast to the MCP49xx series >>> of DACs which use an external voltage reference. >>> >>> Thus, these need a separate binding, as to not overcomplicate >>> the mcp4922 binding. >> >> The difference is just one property which is very easy to handle - one >> allOf:if:then: with >> vref-supply: false >> >> Are there any other differences? >> >> Best regards, >> Krzysztof >> >> > > In place of the external vref input, the MCP48XX series chips also > have a "SHDN" input, which is an active-low pin to disable the whole > chip and put it in a low power state. Future users of the bindings > may want to model this as being tied to some GPIO, though I haven't > done it here since I don't care about this feature. OK to keep them separate, but then you should add here powerdown-gpios. Bindings should be complete. Best regards, Krzysztof
diff --git a/Documentation/devicetree/bindings/iio/dac/microchip,mcp4822.yaml b/Documentation/devicetree/bindings/iio/dac/microchip,mcp4822.yaml new file mode 100644 index 000000000000..c6eaf0079add --- /dev/null +++ b/Documentation/devicetree/bindings/iio/dac/microchip,mcp4822.yaml @@ -0,0 +1,49 @@ +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/iio/dac/microchip,mcp4822.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Microchip MCP4801, MCP4802, MCP4811, MCP4812, MCP4821 and MCP4822 SPI DACs + +maintainers: + - Nicolas Frattaroli <frattaroli.nicolas@gmail.com> + +properties: + compatible: + enum: + - microchip,mcp4801 + - microchip,mcp4802 + - microchip,mcp4811 + - microchip,mcp4812 + - microchip,mcp4821 + - microchip,mcp4822 + + reg: + maxItems: 1 + + vdd-supply: true + +required: + - compatible + - reg + - vdd-supply + +allOf: + - $ref: /schemas/spi/spi-peripheral-props.yaml# + +unevaluatedProperties: false + +examples: + - | + spi { + #address-cells = <1>; + #size-cells = <0>; + + dac@0 { + compatible = "microchip,mcp4821"; + reg = <0>; + vdd-supply = <&dac_reg>; + }; + }; +...
The MCP4801, MCP4802, MCP4811, MCP4812, MCP4821, and MCP4822 are SPI digital-to-analog converters by Microchip, which have an internal voltage reference, in contrast to the MCP49xx series of DACs which use an external voltage reference. Thus, these need a separate binding, as to not overcomplicate the mcp4922 binding. Signed-off-by: Nicolas Frattaroli <frattaroli.nicolas@gmail.com> --- .../bindings/iio/dac/microchip,mcp4822.yaml | 49 +++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/dac/microchip,mcp4822.yaml