Re: [PATCH 1/2] dt-bindings: iio: adc: add lltc,ltc2387

[Krzysztof Kozlowski <krzk@kernel.org>]

On Tue, Oct 27, 2026 at 03:44:08PM +0200, Nicolae-Daniel Deaconescu wrote:
> From: Sergiu Cuciurean <sergiu.cuciurean@analog.com>
> 
> Add bindings for the LTC2387-16 and LTC2387-18, 15 Msps SAR ADCs with
> an LVDS data interface, and for the ADAQ23875, ADAQ23876 and ADAQ23878
> uModule ADCs, which pair an LTC2387 die with a fully differential
> amplifier front end.
> 
> Conversion start (CNV) and the gated LVDS clock are driven by two PWM
> channels. Sample data is captured by an AXI ADC IP core, referenced
> through io-backends. adi,use-two-lanes selects two-lane output, and
> adi,gain-milli gives the front-end gain: fixed at 2 on the ADAQ23875,
> set by pin strapping on the ADAQ23876 and ADAQ23878.
> 
> Signed-off-by: Sergiu Cuciurean <sergiu.cuciurean@analog.com>
> Co-developed-by: Nicolae-Daniel Deaconescu <Nicolae-daniel.Deaconescu@analog.com>
> Signed-off-by: Nicolae-Daniel Deaconescu <Nicolae-daniel.Deaconescu@analog.com>
> Assisted-by: Claude:claude-opus-5-5

Drop tag. Not correct value for some time and recently checkpatch
complains. Anyway, your tag is the last one.

Please run scripts/checkpatch.pl on the patches and fix reported
warnings. After that, run also 'scripts/checkpatch.pl --strict' on the
patches and (probably) fix more warnings. Some warnings can be ignored,
especially from --strict run, but the code here looks like it needs a
fix. Feel free to get in touch if the warning is not clear.

> ---
>  .../bindings/iio/adc/lltc,ltc2387.yaml        | 138 ++++++++++++++++++
>  MAINTAINERS                                   |   8 +
>  2 files changed, 146 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/adc/lltc,ltc2387.yaml
> 
> diff --git a/Documentation/devicetree/bindings/iio/adc/lltc,ltc2387.yaml b/Documentation/devicetree/bindings/iio/adc/lltc,ltc2387.yaml
> new file mode 100644
> index 000000000000..f912260c8f79
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/adc/lltc,ltc2387.yaml
> @@ -0,0 +1,138 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +# Copyright 2022 Analog Devices Inc.
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/adc/lltc,ltc2387.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Linear Technology / Analog Devices LTC2387 ADC
> +
> +maintainers:
> +  - Sergiu Cuciurean <sergiu.cuciurean@analog.com>
> +  - Nicolae-Daniel Deaconescu <Nicolae-daniel.Deaconescu@analog.com>
> +
> +description: |
> +  The LTC2387-18 is a low noise, high speed, 18-bit 15Msps
> +  successive approximation register (SAR) ADC ideally
> +  suited for a wide range of applications.
> +
> +  https://www.analog.com/media/en/technical-documentation/data-sheets/238718fa.pdf
> +  https://www.analog.com/media/en/technical-documentation/data-sheets/238716f.pdf
> +
> +properties:
> +  compatible:
> +    enum:
> +      - adi,adaq23875
> +      - adi,adaq23876
> +      - adi,adaq23878
> +      - lltc,ltc2387-16
> +      - lltc,ltc2387-16-x4
> +      - lltc,ltc2387-18
> +      - lltc,ltc2387-18-x4
> +
> +  clocks:
> +    description: Sampling clock
> +    maxItems: 1
> +
> +  pwms:
> +    maxItems: 2
> +    description:
> +      PWM signals used to synchronize the sampling procedure
> +
> +  pwm-names:
> +    items:
> +      - const: cnv
> +      - const: clk_gate
> +
> +  io-backends:
> +    description:
> +      The AXI ADC IP block (axi_ltc2387) that captures the LVDS data stream.
> +    maxItems: 1
> +
> +  vref-supply:
> +    description:
> +      External voltage reference. When absent the device's internal 4.096 V
> +      reference is assumed.
> +
> +  adi,use-two-lanes:
> +    description: The device uses two lanes for data transfer
> +    type: boolean
> +
> +  adi,gain-milli:
> +    description:
> +      Gain of the fully-differential amplifier that the ADAQ2387x modules
> +      integrate ahead of the LTC2387 die, expressed as gain * 1000. It is
> +      fixed on the ADAQ23875 and set by pin strapping on the ADAQ23876 and
> +      ADAQ23878, so it must match the board. The bare ltc2387-* parts have
> +      no amplifier.
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    enum: [370, 730, 870, 1380, 2000, 2250]
> +
> +required:
> +  - compatible
> +  - clocks
> +  - io-backends
> +  - pwms
> +  - pwm-names
> +
> +allOf:
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              - lltc,ltc2387-16
> +              - lltc,ltc2387-16-x4
> +              - lltc,ltc2387-18
> +              - lltc,ltc2387-18-x4
> +    then:
> +      properties:
> +        adi,gain-milli: false
> +
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            const: adi,adaq23875
> +    then:
> +      properties:
> +        adi,gain-milli:
> +          const: 2000
> +
> +  - if:
> +      properties:
> +        compatible:
> +          contains:
> +            enum:
> +              - adi,adaq23876
> +              - adi,adaq23878
> +    then:
> +      properties:
> +        adi,gain-milli:
> +          enum: [370, 730, 870, 1380, 2250]
> +      required:
> +        - adi,gain-milli
> +
> +additionalProperties: false
> +
> +examples:
> +  - |
> +    adc {
> +            compatible = "lltc,ltc2387-16";

Use 4 spaces for example indentation.

Please run dt-check-style.

Best regards,
Krzysztof