Re: [PATCH 1/2] dt-bindings: iio: adc: adding MCP3564 ADC

From: Jonathan Cameron
Date: Sun May 28 2023 - 15:00:09 EST


On Wed, 24 May 2023 12:37:43 +0200
Mike Looijmans <mike.looijmans@xxxxxxxx> wrote:

> On 19-05-2023 18:01, marius.cristea@xxxxxxxxxxxxx wrote:
> > From: Marius Cristea <marius.cristea@xxxxxxxxxxxxx>
> >
> > This is the device tree schema for iio driver for
> > Microchip family of 153.6 ksps, Low-Noise 16/24-Bit
> > Delta-Sigma ADCs with an SPI interface.
> >
> > Signed-off-by: Marius Cristea <marius.cristea@xxxxxxxxxxxxx>
> > ---
> > .../bindings/iio/adc/microchip,mcp3564.yaml | 88 +++++++++++++++++++
> > 1 file changed, 88 insertions(+)
> > create mode 100644 Documentation/devicetree/bindings/iio/adc/microchip,mcp3564.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/iio/adc/microchip,mcp3564.yaml b/Documentation/devicetree/bindings/iio/adc/microchip,mcp3564.yaml
> > new file mode 100644
> > index 000000000000..407a125e3776
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/iio/adc/microchip,mcp3564.yaml
> > @@ -0,0 +1,88 @@
> > +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/iio/adc/microchip,mcp3564.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Microchip MCP346X and MCP356X ADC Family
> > +
> > +maintainers:
> > + - Marius Cristea <marius.cristea@xxxxxxxxxxxxx>
> > +
> > +description: |
> > + Bindings for the Microchip family of 153.6 ksps, Low-Noise 16/24-Bit
> > + Delta-Sigma ADCs with an SPI interface.
> > +
> > +properties:
> > + compatible:
> > + enum:
> > + - microchip,mcp3461
> > + - microchip,mcp3462
> > + - microchip,mcp3464
> > + - microchip,mcp3461r
> > + - microchip,mcp3462r
> > + - microchip,mcp3464r
> > + - microchip,mcp3561
> > + - microchip,mcp3562
> > + - microchip,mcp3564
> > + - microchip,mcp3561r
> > + - microchip,mcp3562r
> > + - microchip,mcp3564r
> > +
> > + reg:
> > + maxItems: 1
> > +
> > + spi-max-frequency: true
> > +
> > + spi-cpha: true
> > +
> > + spi-cpol: true
> > +
> > + vref-supply:
> > + description:
> > + Some devices have a specific reference voltage supplied on a different
> > + pin to the other supplies. Needed to be able to establish channel scaling
> > + unless there is also an internal reference available (e.g. mcp3564r)
> > +
> > + microchip,hw-device-address:
> > + $ref: /schemas/types.yaml#/definitions/uint32
> > + minimum: 0
> > + maximum: 3
> > + description:
> > + The address is set on a per-device basis by fuses in the factory,
> > + configured on request. If not requested, the fuses are set for 0x1.
> > + The device address is part of the device markings to avoid
> > + potential confusion. This address is coded on two bits, so four possible
> > + addresses are available when multiple devices are present on the same
> > + SPI bus with only one Chip Select line for all devices.
> > +
> > + "#io-channel-cells":
>
> That's a typo, "io" should be "iio", right?

Nope. I honestly can't remember the history behind that, but it's
just io. Probably to do with IIO being Linux specific and this needing
to be generic, but its just an educated guess.

Jonathan