Re: [v4 01/15] dt-bindings: iio: adc: Add ast2600-adc bindings

Rob Herring
2021-08-24T12:13:11Z

On Mon, Aug 23, 2021 at 03:02:26PM +0800, Billy Tsai wrote:
> Add device tree bindings document for the aspeed ast2600 adc device
> driver.
>
> Signed-off-by: Billy Tsai <billy_tsai@aspeedtech.com>
> ---
> .../bindings/iio/adc/aspeed,ast2600-adc.yaml | 97 +++++++++++++++++++
> 1 file changed, 97 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/iio/adc/aspeed,ast2600-adc.yaml
>
> diff --git a/Documentation/devicetree/bindings/iio/adc/aspeed,ast2600-adc.yaml b/Documentation/devicetree/bindings/iio/adc/aspeed,ast2600-adc.yaml
> new file mode 100644
> index 000000000000..248cda7d91e9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/aspeed,ast2600-adc.yaml
> @@ -0,0 +1,97 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/adc/aspeed,ast2600-adc.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: ADC that forms part of an ASPEED server management processor.
> +
> +maintainers:
> + - Billy Tsai <billy_tsai@aspeedtech.com>
> +
> +description: |
> + • 10-bits resolution for 16 voltage channels.
> + • The device split into two individual engine and each contains 8 voltage
> + channels.
> + • Channel scanning can be non-continuous.
> + • Programmable ADC clock frequency.
> + • Programmable upper and lower threshold for each channels.
> + • Interrupt when larger or less than threshold for each channels.
> + • Support hysteresis for each channels.
> + • Built-in a compensating method.
> + • Built-in a register to trim internal reference voltage.
> + • Internal or External reference voltage.
> + • Support 2 Internal reference voltage 1.2v or 2.5v.
> + • Integrate dividing circuit for battery sensing.
> +
> +properties:
> + compatible:
> + enum:
> + - aspeed,ast2600-adc0
> + - aspeed,ast2600-adc1

What's the difference between 0 and 1?

> +
> + reg:
> + maxItems: 1
> +
> + clocks:
> + description:
> + Input clock used to derive the sample clock. Expected to be the
> + SoC's APB clock.

How many clocks?

> +
> + resets:
> + maxItems: 1
> +
> + "#io-channel-cells":
> + const: 1
> +
> + vref-supply:
> + description:
> + The external regulator supply ADC reference voltage.
> +
> + aspeed,int_vref_mv:

Don't use '_' in property names.

Use standard unit suffixes as defined in property-units.yaml.

> + $ref: /schemas/types.yaml#/definitions/uint32

And then you can drop this.

> + enum: [1200, 2500]
> + description:
> + ADC internal reference voltage in millivolts.
> +
> + aspeed,battery-sensing:
> + type: boolean
> + description:
> + Inform the driver that last channel will be used to sensor battery.
> +
> + aspeed,trim-data-valid:
> + type: boolean
> + description: |
> + The ADC reference voltage can be calibrated to obtain the trimming
> + data which will be stored in otp. This property informs the driver that
> + the data store in the otp is valid.
> +
> +required:
> + - compatible
> + - reg
> + - clocks
> + - resets
> + - "#io-channel-cells"
> +
> +additionalProperties: false
> +
> +examples:
> + - |
> + #include <dt-bindings/clock/ast2600-clock.h>
> + adc0: adc@1e6e9000 {
> + compatible = "aspeed,ast2600-adc0";
> + reg = <0x1e6e9000 0x100>;
> + clocks = <&syscon ASPEED_CLK_APB2>;
> + resets = <&syscon ASPEED_RESET_ADC>;
> + #io-channel-cells = <1>;
> + aspeed,int_vref_mv = <2500>;
> + };
> + adc1: adc@1e6e9100 {
> + compatible = "aspeed,ast2600-adc1";
> + reg = <0x1e6e9100 0x100>;
> + clocks = <&syscon ASPEED_CLK_APB2>;
> + resets = <&syscon ASPEED_RESET_ADC>;
> + #io-channel-cells = <1>;
> + aspeed,int_vref_mv = <2500>;
> + };
> +...
> --
> 2.25.1
>
>