From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 24C7B3AE6E4; Wed, 1 Jul 2026 19:39:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782934778; cv=none; b=C6YiHHzhPKxFHICTZPkUM7FJJ8AKF3+/h7Ifls4QmkjCNWC3ZD7S0wt59DsDK1EBFG3nUCyZFE5Ci08j4/AfojYPuzRmafVJtSo0Wmo1ZLwauzBykKmLL6OhHMQzYZRF1IJdeHMfknflOjchgyMj3+QCgUp6RBks4/yYw5D3QU0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782934778; c=relaxed/simple; bh=Ir58o5d3aiQ1D+TysP++ASg5OFXwIwp8eXpHJRU75u8=; h=Date:From:To:Cc:Subject:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=anUcBY231hx1+HVUEK+PTRdmLQgbCOkXBfVmSTZcvS9L0U9HSUaRHGrQbvhfZFpQDZ8Bs69N5B/HGR8Y2J9RGe2usJamNGmk7kDenmrCZOTQHHRgMyz50K375ZXKZPxM+hms6un07ek/cifvZXGfbui8ibvtb9EoLI8LJ/0S2zg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=TBFuOb0O; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="TBFuOb0O" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B0AD11F000E9; Wed, 1 Jul 2026 19:39:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782934776; bh=jy5ObGLgOB0CshRS3p6Ild0t4meQ24n2gU34SJVTSw0=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=TBFuOb0O/94MFU8S5lbwDjpIHvEal+YgKke9mcl7pft9sftg3eeiBwM2LZDOtoXza H/ib9x1LjF9jrnZydEBtn64NDkAFCcrPfEKEy3OsvAn0jkoVzziNLylBrlUS2UaWzH iSxrgLQU9EmWd3MYf0OVPjuQ9InhksCz0ekdUxdVxrfVqDpaS98j+2xmTqlSyQrgCK nRoOEjmliT/z0cDvVBxCvSYdQ3UkmT8iKIz0o5zNaJ329nMGsEdolItd+hgLQ0Rj6U YA4RyYMtpJKfHMF6r2RdGQxq1zLZMTpSZU6yQJgPLruVdovPQaAF8UXwiCU75DQmSN yXNfnevqtZM1w== Date: Wed, 1 Jul 2026 20:39:32 +0100 From: Jonathan Cameron To: David Lechner Cc: Nuno =?UTF-8?B?U8Oh?= , Andy Shevchenko , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Chris Hall , Patrick Edwards , Kurt Borja , Nguyen Minh Tien , linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 2/8] dt-bindings: iio: adc: Add excitation current sources properties Message-ID: <20260701203932.20e688db@jic23-huawei> In-Reply-To: <20260625-iio-adc-ti-ads122c14-v2-2-ceb9b0b561cb@baylibre.com> References: <20260625-iio-adc-ti-ads122c14-v2-0-ceb9b0b561cb@baylibre.com> <20260625-iio-adc-ti-ads122c14-v2-2-ceb9b0b561cb@baylibre.com> X-Mailer: Claws Mail 4.4.0 (GTK 3.24.52; x86_64-pc-linux-gnu) Precedence: bulk X-Mailing-List: linux-iio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit On Thu, 25 Jun 2026 16:55:04 -0500 David Lechner wrote: > From: Kurt Borja > > 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. > > Signed-off-by: Kurt Borja > Signed-off-by: David Lechner (TI) > --- > v2 changes (compared to Kurt's RFC v2): > * Make units nanoamps instead of microamps to fit known devices. > * Drop bit about allowing single value for multiple channels. > * Add bit about semantics of the array index. > --- > Documentation/devicetree/bindings/iio/adc/adc.yaml | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/Documentation/devicetree/bindings/iio/adc/adc.yaml b/Documentation/devicetree/bindings/iio/adc/adc.yaml > index 12800737d4fb..860601ec5334 100644 > --- a/Documentation/devicetree/bindings/iio/adc/adc.yaml > +++ b/Documentation/devicetree/bindings/iio/adc/adc.yaml > @@ -81,6 +81,26 @@ properties: > ADCs usually allow choosing between internal reference sources or a pair > of external pins. > > + excitation-channels: How would this apply if a device provided excitation on pins that didn't correspond to channels? i.e. some extra ones. Perhaps such a device that also supports configuration (rather than a static set up) would just need a different binding. Feels like I'm creating a corner case we may never see :) > + $ref: /schemas/types.yaml#/definitions/uint32-array > + 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-nanoamp: > + 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. The index in the array corresponds to the same index in the > + excitation-channels array. > + > anyOf: > - oneOf: > - required: >