From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 01BE61420C9; Mon, 8 Jul 2024 14:59:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720450766; cv=none; b=srQ7wEYL1wNh2WaidHG+WrWtGca4ogXRe6pIJQhivl/R0CRdh3r0YYgBS68VbQG+Uq91da2njtIcoSJlPltdra6wXr2zUn8urHcmN1o4wk1hnRvcbIwl0/K1RGF8hTgNg4RpofiBnfBgU18ki3ajHiTnwPC0jtKMBVQr7f1yNog= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720450766; c=relaxed/simple; bh=oLZHFnJFNi8m8krEoLGQPvZmgohhon3PIubl9n/KAV0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=sJOa/ACZe3kQI8otI3pjfkXnYdOwqzpxFdip3ieolsXJheao5lzp58h3CWK2wV0yLyEx9FMx8riPlSq26fi7i/pWotQpbWvoCbqnOODjZx+7xVu09G1WSbzM/5NdJrFtKJiYOQJ6/Hj+F6m9D53RBUdctHZ0XnH+wmNGDNgoQeg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=pZdvM0Iu; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="pZdvM0Iu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 568C6C4AF0A; Mon, 8 Jul 2024 14:59:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1720450765; bh=oLZHFnJFNi8m8krEoLGQPvZmgohhon3PIubl9n/KAV0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=pZdvM0Iu0OAPSpNVJKkpK9Vv6BQAv/6gpvZLKeQtspun5Rxp50KwfkVTUFdSLbjI7 eAsCveae79U87T998w3/3UZaUHRqIlMW+xnXJQRzH5LA4a3JmmBhUFGAgGeRSZiBoG OWxiUxzLSaUZ2IS9b4ONFIiXx+3/nxpL281+IU4BboUJbGLBzXEAX9Tl48hWErU7aq 8gHJnqn9zE1d2yR6kA6tcSLqlxWAOBGcgq+oZMn+unZuTgBujNOS0TmXgoQ/VTZJA7 iJ2RGI3vXm8juu7HyUwWCdRWvwomvFdRdD7TQwnD6p/9X7v8TIG4/f+5jqNuwBlq2E GLurkwq23lFCA== Date: Mon, 8 Jul 2024 16:59:23 +0200 From: Maxime Ripard To: Marc Gonzalez Cc: Conor Dooley , Krzysztof Kozlowski , Rob Herring , Andrzej Hajda , Neil Armstrong , Robert Foss , Laurent Pinchart , Jonas Karlman , Jernej Skrabec , Maarten Lankhorst , Thomas Zimmermann , David Airlie , Daniel Vetter , Liam Girdwood , Mark Brown , dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-arm-msm@vger.kernel.org, Arnaud Vrac , Pierre-Hugues Husson , Dmitry Baryshkov Subject: Re: [PATCH v3 1/2] dt-bindings: display: bridge: add TI TDP158 Message-ID: <20240708-ethereal-romantic-piculet-d4ae66@houat> References: <20240627-tdp158-v3-0-fb2fbc808346@freebox.fr> <20240627-tdp158-v3-1-fb2fbc808346@freebox.fr> <20240701-bug-of-great-honeydew-cfb6ef@houat> 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-sha384; protocol="application/pgp-signature"; boundary="kopfx6abx7uf4ddg" Content-Disposition: inline In-Reply-To: --kopfx6abx7uf4ddg Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Jul 01, 2024 at 05:36:18PM GMT, Marc Gonzalez wrote: > On 01/07/2024 15:50, Maxime Ripard wrote: >=20 > > On Thu, Jun 27, 2024 at 01:13:03PM GMT, Marc Gonzalez wrote: > > > >> TDP158 is an AC-coupled DVI / HDMI to TMDS level shifting Redriver. > >> It supports DVI 1.0, HDMI 1.4b and 2.0b. > >> It supports 4 TMDS channels, HPD, and a DDC interface. > >> It supports dual power supply rails (1.1V on VDD, 3.3V on VCC) > >> for power reduction. Several methods of power management are > >> implemented to reduce overall power consumption. > >> It supports fixed receiver EQ gain using I2C or pin strap to > >> compensate for different lengths input cable or board traces. > >> > >> Features > >> > >> - AC-coupled TMDS or DisplayPort dual-mode physical layer input > >> to HDMI 2.0b TMDS physical layer output supporting up to 6Gbps > >> data rate, compatible with HDMI 2.0b electrical parameters > >> - DisplayPort dual-mode standard version 1.1 > >> - Programmable fixed receiver equalizer up to 15.5dB > >> - Global or independent high speed lane control, pre-emphasis > >> and transmit swing, and slew rate control > >> - I2C or pin strap programmable > >> - Configurable as a DisplayPort redriver through I2C > >> - Full lane swap on main lanes > >> - Low power consumption (200 mW at 6Gbps, 8 mW in shutdown) > >> > >> https://www.ti.com/lit/ds/symlink/tdp158.pdf > >> > >> Signed-off-by: Marc Gonzalez > >> --- > >> .../bindings/display/bridge/ti,tdp158.yaml | 51 +++++++++++++= +++++++++ > >> 1 file changed, 51 insertions(+) > >> > >> diff --git a/Documentation/devicetree/bindings/display/bridge/ti,tdp15= 8.yaml b/Documentation/devicetree/bindings/display/bridge/ti,tdp158.yaml > >> new file mode 100644 > >> index 0000000000000..21c8585c3bb2d > >> --- /dev/null > >> +++ b/Documentation/devicetree/bindings/display/bridge/ti,tdp158.yaml > >> @@ -0,0 +1,51 @@ > >> +# SPDX-License-Identifier: GPL-2.0-only > >> +%YAML 1.2 > >> +--- > >> +$id: http://devicetree.org/schemas/display/bridge/ti,tdp158.yaml# > >> +$schema: http://devicetree.org/meta-schemas/core.yaml# > >> + > >> +title: TI TDP158 HDMI to TMDS Redriver > >> + > >> +maintainers: > >> + - Arnaud Vrac > >> + - Pierre-Hugues Husson > >> + > >> +properties: > >> + compatible: > >> + const: ti,tdp158 > >> + > >> + reg: > >> + description: I2C address of the device > >> + > >> + enable-gpios: > >> + description: GPIO controlling bridge enable > >> + > >> + vcc-supply: > >> + description: Power supply 3.3V > >> + > >> + vdd-supply: > >> + description: Power supply 1.1V > >> + > >> + ports: > >> + $ref: /schemas/graph.yaml#/properties/ports > >> + > >> + properties: > >> + port@0: > >> + $ref: /schemas/graph.yaml#/properties/port > >> + description: Bridge input > >> + > >> + port@1: > >> + $ref: /schemas/graph.yaml#/properties/port > >> + description: Bridge output > >> + > >> + required: > >> + - port@0 > >> + - port@1 > >=20 > > The device supports DVI, HDMI or DP input, with various requirements and > > capabilities depending on the input. Your binding doesn't address that. > >=20 > > Similarly, it can do lane-swapping, so we should probably have a > > property to describe what mapping we want to use. > >=20 > > The i2c register access (and the whole behaviour of the device) is > > constrained on the I2C_EN pin status, and you can't read it from the > > device, so it's also something we need to have in the DT. >=20 > We are using the device in its default configuration. > (Power on via OE, then it works as expected) I know, but that doesn't really matter for a binding. > Can we leave any additional properties to be defined by whomever needs > them in the future? If you can guarantee that doing so would be backward compatible, sure. But that means being able to answer those questions with a reasonable plan. Maxime --kopfx6abx7uf4ddg Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iJUEABMJAB0WIQTkHFbLp4ejekA/qfgnX84Zoj2+dgUCZov+ygAKCRAnX84Zoj2+ dv/EAYDdyYxojHqIYebCO337L4bW6W074cgkpmwvgnbWAVxCRWViDUMdUTpKAXxf odUWQ6IBgJrGQ3od02hFC2F34PHn8/vUxZk9Lb2LuSmabRyII/7jnymhYesMtmfF 2INbhUBK+A== =HW4H -----END PGP SIGNATURE----- --kopfx6abx7uf4ddg--