| Message ID | BN6PR04MB06600A3AFE160C6E07BF5B2CA3BA0@BN6PR04MB0660.namprd04.prod.outlook.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | iio: adc: Add a current from voltage driver | expand |
On Fri, May 15, 2020 at 07:26:18PM -0700, Jonathan Bakker wrote: > Some devices may require a current adc, but only have a voltage > ADC onboard. In order to read the current, they have a resistor > connected to the ADC. Add bindings for this possibility. > > Signed-off-by: Jonathan Bakker <xc-racer2@live.ca> > --- > .../iio/adc/linux,current-from-voltage.yaml | 47 +++++++++++++++++++ > 1 file changed, 47 insertions(+) > create mode 100644 Documentation/devicetree/bindings/iio/adc/linux,current-from-voltage.yaml > > diff --git a/Documentation/devicetree/bindings/iio/adc/linux,current-from-voltage.yaml b/Documentation/devicetree/bindings/iio/adc/linux,current-from-voltage.yaml > new file mode 100644 > index 000000000000..385d317607c3 > --- /dev/null > +++ b/Documentation/devicetree/bindings/iio/adc/linux,current-from-voltage.yaml > @@ -0,0 +1,47 @@ > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) > +%YAML 1.2 > +--- > +$id: http://devicetree.org/schemas/iio/adc/linux,current-from-voltage.yaml# > +$schema: http://devicetree.org/meta-schemas/core.yaml# > + > +title: Current ADC from voltage ADC and resistor > + > +maintainers: > + - Jonathan Bakker <xc-racer2@live.ca> > + > +properties: > + compatible: > + const: linux,current-from-voltage How is an ADC with a resistor attached a Linux thing? So you don't need 'linux', but then 'current-from-voltage' isn't the best naming. I don't have a suggestion ATM. > + > + io-channel-names: > + const: adc > + > + io-channels: > + maxItems: 1 > + description: Voltage ADC channel > + > + linux,resistor-ohms: > + description: Strength of resistor connected to voltage ADC Wouldn't you need this to be micro-ohms? Otherwise, there'd be too much voltage drop? Rob
Hi Rob, On 2020-05-28 1:13 p.m., Rob Herring wrote: > On Fri, May 15, 2020 at 07:26:18PM -0700, Jonathan Bakker wrote: >> Some devices may require a current adc, but only have a voltage >> ADC onboard. In order to read the current, they have a resistor >> connected to the ADC. Add bindings for this possibility. >> >> Signed-off-by: Jonathan Bakker <xc-racer2@live.ca> >> --- >> .../iio/adc/linux,current-from-voltage.yaml | 47 +++++++++++++++++++ >> 1 file changed, 47 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/iio/adc/linux,current-from-voltage.yaml >> >> diff --git a/Documentation/devicetree/bindings/iio/adc/linux,current-from-voltage.yaml b/Documentation/devicetree/bindings/iio/adc/linux,current-from-voltage.yaml >> new file mode 100644 >> index 000000000000..385d317607c3 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/iio/adc/linux,current-from-voltage.yaml >> @@ -0,0 +1,47 @@ >> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) >> +%YAML 1.2 >> +--- >> +$id: http://devicetree.org/schemas/iio/adc/linux,current-from-voltage.yaml# >> +$schema: http://devicetree.org/meta-schemas/core.yaml# >> + >> +title: Current ADC from voltage ADC and resistor >> + >> +maintainers: >> + - Jonathan Bakker <xc-racer2@live.ca> >> + >> +properties: >> + compatible: >> + const: linux,current-from-voltage > > How is an ADC with a resistor attached a Linux thing? So you don't need > 'linux', but then 'current-from-voltage' isn't the best naming. I don't > have a suggestion ATM. > The good/bad news is that I was re-implementing an existing driver under a new name :) The compatible is current-sense-shunt for this exact same purpose. Thanks, Jonathan >> + >> + io-channel-names: >> + const: adc >> + >> + io-channels: >> + maxItems: 1 >> + description: Voltage ADC channel >> + >> + linux,resistor-ohms: >> + description: Strength of resistor connected to voltage ADC > > Wouldn't you need this to be micro-ohms? Otherwise, there'd be too much > voltage drop? > > Rob >
diff --git a/Documentation/devicetree/bindings/iio/adc/linux,current-from-voltage.yaml b/Documentation/devicetree/bindings/iio/adc/linux,current-from-voltage.yaml new file mode 100644 index 000000000000..385d317607c3 --- /dev/null +++ b/Documentation/devicetree/bindings/iio/adc/linux,current-from-voltage.yaml @@ -0,0 +1,47 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/iio/adc/linux,current-from-voltage.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Current ADC from voltage ADC and resistor + +maintainers: + - Jonathan Bakker <xc-racer2@live.ca> + +properties: + compatible: + const: linux,current-from-voltage + + io-channel-names: + const: adc + + io-channels: + maxItems: 1 + description: Voltage ADC channel + + linux,resistor-ohms: + description: Strength of resistor connected to voltage ADC + + "#io-channel-cells": + const: 0 + +required: + - compatible + - io-channel-names + - io-channels + - linux,resistor-ohms + - "#io-channel-cells" + +examples: + - | + current-from-voltage { + compatible = "linux,current-from-voltage"; + io-channel-names = "adc"; + io-channels = <&adc 9>; + linux,resistor-ohms = <47>; + #io-channel-cells = <0>; + io-channel-ranges; + }; + +...
Some devices may require a current adc, but only have a voltage ADC onboard. In order to read the current, they have a resistor connected to the ADC. Add bindings for this possibility. Signed-off-by: Jonathan Bakker <xc-racer2@live.ca> --- .../iio/adc/linux,current-from-voltage.yaml | 47 +++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 Documentation/devicetree/bindings/iio/adc/linux,current-from-voltage.yaml