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([2600:8803:e7e4:500:dd8:d93b:3cde:c07]) by smtp.gmail.com with ESMTPSA id 46e09a7af769-7e92ecfcc9csm1932228a34.21.2026.06.19.07.27.10 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 19 Jun 2026 07:27:11 -0700 (PDT) Message-ID: <073b0a89-65af-4a21-837d-851d35e3e294@baylibre.com> Date: Fri, 19 Jun 2026 09:27:10 -0500 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH RFC 2/3] dt-bindings: iio: adc: Add excitation current sources properties To: Kurt Borja , Jonathan Cameron , Rob Herring , Krzysztof Kozlowski , Conor Dooley Cc: =?UTF-8?Q?Nuno_S=C3=A1?= , Andy Shevchenko , linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org References: <20260618-new-channel-props-v1-0-963c1b5cf40a@gmail.com> <20260618-new-channel-props-v1-2-963c1b5cf40a@gmail.com> Content-Language: en-US From: David Lechner In-Reply-To: <20260618-new-channel-props-v1-2-963c1b5cf40a@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 6/18/26 7:33 PM, Kurt Borja wrote: > Some ADCs incorporate current sources that provide excitation current to > resistive temperature devices (RTDs), thermistors diodes and other > resistive sensors that require constant current biasing. > > The maxItems constraint of 16 is arbitrary but should be big enough for > most devices. I wouldn't put an arbitrary limit here. The bindings that include it can extend it to add a limit that makes sense instead. > > Signed-off-by: Kurt Borja > --- > Documentation/devicetree/bindings/iio/adc/adc.yaml | 23 ++++++++++++++++++++++ > 1 file changed, 23 insertions(+) > > diff --git a/Documentation/devicetree/bindings/iio/adc/adc.yaml b/Documentation/devicetree/bindings/iio/adc/adc.yaml > index c74c2084fdb68c..106b1e317411d5 100644 > --- a/Documentation/devicetree/bindings/iio/adc/adc.yaml > +++ b/Documentation/devicetree/bindings/iio/adc/adc.yaml > @@ -83,6 +83,29 @@ properties: > This array describes either a single reference source or a positive and > negative reference sources. > > + excitation-channels: > + $ref: /schemas/types.yaml#/definitions/uint32-array > + maxItems: 16 > + minItems: 1 > + description: > + Excitation current sources provide current to resistive temperature > + devices (RTDs), thermistors diodes and other resistive sensors that > + require constant current biasing. > + > + This array describes the mux configuration of the excitation current > + sources. > + > + excitation-current-microamp: > + maxItems: 16 > + minItems: 1 > + description: > + Excitation current sources provide current to resistive temperature > + devices (RTDs), thermistors diodes and other resistive sensors that > + require constant current biasing. > + > + This array describes the current configuration of the excitation current > + sources or the single matched current for all sources. > + > anyOf: > - oneOf: > - required: >