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 48A0E372663; Wed, 30 Sep 2026 12:15:04 +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=1790770506; cv=none; b=Nt5KNu1PmFfv10Jv75R6wOnFyRB+zTtu4avQGA8TN829eDg414IEj9JBglxk3deh1jBrBwjZUbeygkxkiZPXIPAEK/B0hpq9JLUbkhJZ+LtvkYSuVZUuQPgqbSCi2w+xYFrJRhZNH4Z13XXe3R23RvFWtKHeWW7TkYmk0hlQzf4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790770506; c=relaxed/simple; bh=xv0RqiOiKwlaT0J82cr/0v5YvERfM3N4VNRX1rS/bg4=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Y/qqG0mlp3cFwIUbbfrxK31phJMLHa1DltfaWgrOTTuatS02Y0kyiMVgKeilHRTsRXWqjeAscI/hnboqWNY8nGvc4Ua25pkupM5cxgNQQDP7wGyKFJRhKfc8fb2r779XkdN4elHjSseHEOLvLRfQPJBdoU0Co19R6kIYEFwuFV4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=a9VxevWX; 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="a9VxevWX" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A55151F000FF; Wed, 30 Sep 2026 12:15:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790770504; bh=Nc/fukDyXazndbYcPYi1K6bg0O60HvWUrSB7JCmYXcg=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=a9VxevWX5+tyC0lAYyQhbtuNuG60oulZbAJ18Kc7HkkaVy5TnineeBk6utelzOqIe /rGKfA3+RMvNjbL5bEq0CArAuB23/raRAOUuLN7aSPo1WxTMzIerD5hW5YWgZtcg7k ulzYB8vCEpasQ//khaB8A8V2q+pHqE8o0VC8OcF+oQ4XadEBvw3fNhlroGMmesvntm OdMuY27shJHFHI+AATFV5nJvc28gbtgAH2PGkQg2xe8rqAU0tPe8dW4sGvaHmjYBaz 3ilkXEzXic6OhX0BfqNwOlwYntSF41nwRVgP7AOGyRVi5jV/XRZzpfYVZjZ96i78cG f67do4nYc8DGA== Date: Wed, 30 Sep 2026 07:15:02 -0500 From: Rob Herring To: Marcelo Schmitt Cc: linux-iio@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux@analog.com, jic23@kernel.org, nuno.sa@analog.com, dlechner@baylibre.com, andy@kernel.org, Michael.Hennerich@analog.com, krzk+dt@kernel.org, conor+dt@kernel.org, corbet@lwn.net, skhan@linuxfoundation.org, marcelo.schmitt1@gmail.com Subject: Re: [PATCH v3 08/13] dt-bindings: iio: adc: adi,ad4134: Document SPI connection mode Message-ID: <20260930121502.GA2207237-robh@kernel.org> References: <12e5af9d96f6c5e800ad860d3cfa6ac8006a22e2.1790719425.git.marcelo.schmitt@analog.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <12e5af9d96f6c5e800ad860d3cfa6ac8006a22e2.1790719425.git.marcelo.schmitt@analog.com> On Tue, Sep 29, 2026 at 07:44:22PM -0300, Marcelo Schmitt wrote: > Document how AD4134 chips are connected to the host SPI controller > according to different wiring configurations. > > Signed-off-by: Marcelo Schmitt > --- > Change log v2 -> v3: > - Adjusted spi-rx-bus-width constraints. > > Unfortunately, I missed SPI connection mode properties when introducing AD4134 > dt-doc and the device driver defaulted to a no-CS configuration. Due to that, > conventional 4-wire mode can't be made default without leading to a regression. > Still, updating the SPI mode default to 4-wire is a sensible thing to do later > on if acceptable. > > .../bindings/iio/adc/adi,ad4134.yaml | 51 ++++++++++++++++--- > 1 file changed, 44 insertions(+), 7 deletions(-) > > diff --git a/Documentation/devicetree/bindings/iio/adc/adi,ad4134.yaml b/Documentation/devicetree/bindings/iio/adc/adi,ad4134.yaml > index ea6d7e026419..0b2a2cbfadae 100644 > --- a/Documentation/devicetree/bindings/iio/adc/adi,ad4134.yaml > +++ b/Documentation/devicetree/bindings/iio/adc/adi,ad4134.yaml > @@ -131,6 +131,26 @@ properties: > enum: [ free-running, gated ] > default: gated > > + adi,spi-mode: > + $ref: /schemas/types.yaml#/definitions/string > + enum: [ no-cs, 4-wire, one-channel-chain, two-channel-chain ] > + default: no-cs > + description: | > + This property indicates the SPI wiring configuration. > + * no-cs: The datasheet calls this "minimum I/O mode". In this mode, the CS > + line is not used (tied to GND). > + * 4-wire: Specifies a conventional SPI wiring configuration. > + * one-channel-chain: In this mode, the DOUT0 line of one chip is connected > + to DOUT2 of the next chip upstream in the chain. Only the data interface > + of the upmost device in the stream is in direct connection with the > + digital host. > + * two-channel-chain: In this mode, the DOUT0 and DOUT1 lines of one chip > + are respectively connected to DOUT2 and DOUT3 of the next chip upstream > + in the chain. Only the data interface of the upmost device in the stream > + is in direct connection with the digital host. > + > + '#daisy-chained-devices': true > + > required: > - compatible > - reg > @@ -141,13 +161,30 @@ required: > - clocks > - clock-names > > -oneOf: > - - required: > - - ldoin-supply > - - required: > - - avdd1v8-supply > - - dvdd1v8-supply > - - clkvdd-supply > +allOf: > + - oneOf: > + - required: > + - ldoin-supply > + - required: > + - avdd1v8-supply > + - dvdd1v8-supply > + - clkvdd-supply > + > + - oneOf: > + - required: [adi,spi-mode, '#daisy-chained-devices'] > + properties: > + adi,spi-mode: > + const: one-channel-chain > + spi-rx-bus-width: > + const: 1 > + - required: [adi,spi-mode, '#daisy-chained-devices'] > + properties: > + adi,spi-mode: > + const: two-channel-chain > + spi-rx-bus-width: > + const: 1, 1 This is not valid. I think it evaluates to a string. You want: items: - const: 1 - const: 1 Rob