From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from sender4-op-o11.zoho.com (sender4-op-o11.zoho.com [136.143.188.11]) (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 75979320CCC for ; Wed, 15 Jul 2026 19:16:50 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.11 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784143014; cv=pass; b=amlKiug1DfgnofLLk+GwkqVq6SUx1JCzPDNAe7DQWau2XuJTKhIyOSeLEIU4g1SAuhELRiiumS0hD6oFSu41u5UVuVcagUOk2ELS+dm4nFXk+KEOjl4EOmjnguvugYXbOkWVomltSyfPtrYZwwiWggNffxjIv8tRsiHnpcc1YrQ= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784143014; c=relaxed/simple; bh=aIrgBTDaGKbHi60MuWiqEbjkCwmSMECQr/l0VD3Vtyc=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=b2JjqVcsWKphOIG2X2c+9Bc9lrO3NOGLb1jWy5uifyP4VECPVpDsIX7jND+TS6P2Jsc3jwjI7CvgMHcFDivjAMVYo1CqgoTsxsf+pavlno9R4gLT3dyqzxna+u2i7Wbh+XXArW+aRj/olSg8SJ5QcQKNgJS2h2HZgaGCqYwKpeA= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (1024-bit key) header.d=collabora.com header.i=sebastian.reichel@collabora.com header.b=kYjS8uHy; arc=pass smtp.client-ip=136.143.188.11 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=collabora.com header.i=sebastian.reichel@collabora.com header.b="kYjS8uHy" ARC-Seal: i=1; a=rsa-sha256; t=1784142993; cv=none; d=zohomail.com; s=zohoarc; b=LYcr0N8qbpdREd0byDKZ3MBm+lLW9I0Y9sk4UJyNU6hrgKqxD6dc96GZBh/zmhyMrhLhYs0lds4fo/RVR4DESodjeia2fOivhsi74WoKjl25INVLtk7Jcc915N9b+rDLG1T9pZJQJjInr5Zk0juvIDn/ZUcVpW1Tf1JdDfa86yE= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1784142993; h=Content-Type:Cc:Cc:Date:Date:From:From:In-Reply-To:MIME-Version:Message-ID:References:Subject:Subject:To:To:Message-Id:Reply-To; bh=09JIm2bYrw4hSvnoipMr6olQgKBUeyKwwBq6wlZYhsg=; b=LCy4+XqYQbv511aYJOdVy6qU9FEkHnpwBJD60ExMUy94CrLPTW7jQdtGVhFwHnPEURtXajTxVpQGEBlLhY4zU0nzbB9JZggwhfCgsVsfsNM4KnLUDiCxIbIfx8AHAtGbUMi4gSU8obDlfHXLHRmAL69XjtWJuoDHQEcSXJGUZBU= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=sebastian.reichel@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1784142993; s=zohomail; d=collabora.com; i=sebastian.reichel@collabora.com; h=Date:Date:From:From:To:To:Cc:Cc:Subject:Subject:Message-ID:References:MIME-Version:Content-Type:In-Reply-To:Message-Id:Reply-To; bh=09JIm2bYrw4hSvnoipMr6olQgKBUeyKwwBq6wlZYhsg=; b=kYjS8uHyB9w2WWbGcHw0EBAtbE+h+cUbFLCS9pyg/ddfz987xPANA7b2J2EGXeMG XMi4oAKUWHtyoRXNW0h8ckyHkaw+al4s0TcarRkjfeIieHp+dbqeKwTKx5/HMmhW4Ld l9DazjDh3mOWR8GbYA72dB9jbV1STjTOiO7drwKM= Received: by mx.zohomail.com with SMTPS id 1784142990210370.495977626671; Wed, 15 Jul 2026 12:16:30 -0700 (PDT) Received: by venus (Postfix, from userid 1000) id 0C8A6180820; Wed, 15 Jul 2026 21:16:27 +0200 (CEST) Date: Wed, 15 Jul 2026 21:16:27 +0200 From: Sebastian Reichel To: Rob Herring , Krzysztof Kozlowski , Conor Dooley , Dmitry Baryshkov , Dmitry Baryshkov Cc: dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, kernel@collabora.com Subject: Re: [PATCH RFC v3 09/10] dt-bindings: display: rockchip: dw-dp: fix sound DAI cells Message-ID: References: <20260612-synopsys-dw-dp-improvements-v3-0-dc61e6352508@collabora.com> <20260612-synopsys-dw-dp-improvements-v3-9-dc61e6352508@collabora.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha512; protocol="application/pgp-signature"; boundary="wmlwreimakep7qlw" Content-Disposition: inline In-Reply-To: <20260612-synopsys-dw-dp-improvements-v3-9-dc61e6352508@collabora.com> X-Zoho-Virus-Status: 1 X-Zoho-AV-Stamp: zmail-av-0.2.10.1.5.2/284.121.97 X-ZohoMailClient: External --wmlwreimakep7qlw Content-Type: text/plain; protected-headers=v1; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Subject: Re: [PATCH RFC v3 09/10] dt-bindings: display: rockchip: dw-dp: fix sound DAI cells MIME-Version: 1.0 Hi DT binding maintainers (& Dmitry for his DP background), Can you have a look at this please? It has been a month, since I send this and multiple months since I send RFCv1. Would be good to have your preference here, so that I can implement it accordingly in the next version. On Fri, Jun 12, 2026 at 08:00:55PM +0200, Sebastian Reichel wrote: > The RK3588 and RK3576 DesignWare DisplayPort controllers both have two > possible DAI interfaces: I2S and S/PDIF. Thus it is needed to have an > argument to select the right interface. >=20 > In case of RK3576 this is not enough though. The RK3576 has the same IP > as RK3588, but configured with Multi Stream Transport (MST) enabled for > up to 3 displays and thus has a total of 6 DAI interfaces (I2S and > S/PDIF for each possible stream. Meanwhile the RK3588 does not support > MST and thus has only 2 DAI interfaces. >=20 > The binding update right now only supports the simple single stream > transport (SST) setup. To avoid further DT ABI breakage (or complicated > bindings supporting different number of arguments), it's probably a good > idea to take MST into account now even though the upstream Linux driver > does not yet support it. >=20 > I see two options: >=20 > 1. Adding yet another cell, so that we have the following: > <&dp_ctrl [display_stream] [i2s_or_spdif]>; potentially append > extra input ports for MST video data to existing ports node > (e.g. port@2). I would only handle the sound DAI part in my > patch and basically use '0' for the display stream and just > leave the option of using '1' or '2' once MST support is added. My guess is, that this is preferred. > 2. The vendor kernel creates a sub-node for each supported display > stream and puts the ports mapping as well as the DAI reference > into that. This bundles all information for one display stream > together, which creates a clean look but the subnode does not > really describe any real thing in the hardware. FWIW that looks like this: dp@
{ props-from-this-binding; /* SST or MST stream 0 */ dp0 { #sound-dai-cells =3D <1>; ports { ... }; }; /* MST stream 1 */ dp1 { #sound-dai-cells =3D <1>; ports { ... }; }; /* MST stream 2 */ dp2 { #sound-dai-cells =3D <1>; ports { ... }; }; }; While the grouping looks nice to me from the audio/video controller to DP controller point of view, it's less sensible for the connection from the DP controller to the DP/USB-C connector as all streams are bundled at that point. Thanks and greetings, -- Sebastian > As upstream MST support seems to be quite limited, I wish for some > feedback about the preferred way to handle this. >=20 > Signed-off-by: Sebastian Reichel > --- > .../devicetree/bindings/display/rockchip/rockchip,dw-dp.yaml | 5= +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) >=20 > diff --git a/Documentation/devicetree/bindings/display/rockchip/rockchip,= dw-dp.yaml b/Documentation/devicetree/bindings/display/rockchip/rockchip,dw= -dp.yaml > index 2b0d9e23e943..1303d0e2145a 100644 > --- a/Documentation/devicetree/bindings/display/rockchip/rockchip,dw-dp.y= aml > +++ b/Documentation/devicetree/bindings/display/rockchip/rockchip,dw-dp.y= aml > @@ -83,7 +83,8 @@ properties: > maxItems: 1 > =20 > "#sound-dai-cells": > - const: 0 > + const: 1 > + description: 0 for I2S, 1 for SPDIF > =20 > required: > - compatible > @@ -144,7 +145,7 @@ examples: > resets =3D <&cru SRST_DP0>; > phys =3D <&usbdp_phy0 PHY_TYPE_DP>; > power-domains =3D <&power RK3588_PD_VO0>; > - #sound-dai-cells =3D <0>; > + #sound-dai-cells =3D <1>; > =20 > ports { > #address-cells =3D <1>; >=20 > --=20 > 2.53.0 >=20 --wmlwreimakep7qlw Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCgAdFiEE72YNB0Y/i3JqeVQT2O7X88g7+poFAmpX3H8ACgkQ2O7X88g7 +prDaA/+J+o4Ka0pqiKFsl6B5vJAD6vsP+iiE/zqMIa1Q6zE29IVyt3DySRofwBL 99yNQ+3ufn9nTFDyBr1qMAv4LegIqgrM+EucnxPvOD159SS9d+7bFngcVeUh7P47 fUfbjxLqw9QkzK0nQotCc9EyYjQV2a/5JUSqThcIGPPAx3uYdQqlS0hfCdR1GVCe Loa64cD3EOyZ79O1lsDYJ4xEsAtUm+ztHd0t1RMSLUmaq68aNSus/Muh5eHuvzUH AAAQELgud9U/TbtGEBR6AjM2KdthxBJZcnH6bkx8vs4KKAar8KGz9DuEF8na4Nmi IM+k0YIyo2ESWsZGnjK7DmgmtnVk4j8J8LDmHUaTpA+Eg0/fUpW331+I+hLNXjF2 FzObpZ9JkumAZuPnczA2lfBctftuQ9voDHg5PbBfemgK7bdOy+PvgEle4H512bxm nbg3H6BexThWQW7A3WnxvxifoATFhidzN/Awj3oXTjY4Yfemwb3X5jRPZ713TgkG U9kky7/B3NPi19uunkJoDtM2HhA7PqjGUnKw4j06AhzPs433bdD4DVBL6FJRIrO+ UQ4JBJQW8t8JtDYRkvp3mFyBbQTqw8EjeIKxMAPdv2JHEEEOQz1/lyaHNSEdwIoy AdualjvMfi6DKwBpBTfUUDHjMsiDtsiUxeVelpU8KbZeTRafk68= =dfEW -----END PGP SIGNATURE----- --wmlwreimakep7qlw--