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 3C233F4EB; Wed, 21 Aug 2024 00:34:50 +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=1724200490; cv=none; b=C245Pgp40CY0m5bA3KeGr9Dd4K5v9hzmj1vFvYoNy7PVOPmjvS3N4IIY1il7xVsdI9nZAWpgGYQvkJxLHoc5o3+ykP4tmxUzKLMy128BfnmfY0FWz0Z1pKt9IY8OJa1rQED843yqlU37BKojCXI+FSxOC4mvKWce/6lwo0efQKI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1724200490; c=relaxed/simple; bh=fUJI4jZmft/izpLYURRjAmm97Z8N86Ii30QM5siTy/o=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=adiXtWmmmboRA23r3hsMHxVFpP4Ah+w9ew9LCxvl5N4l1dNHjKR7Fw5aG+gx+T1kCQ/MXZBYVcjb1W04SwjcgkPqgegP8cVkNJrwdkF1mLoDoA47DU+UDtKJ5sljKRoK7HGi9cf7Y3yGrF1AA4l+9t55uFTC4C32PiQhVNWLKcQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=H9RNHwUR; 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="H9RNHwUR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 1B451C4AF0E; Wed, 21 Aug 2024 00:34:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1724200490; bh=fUJI4jZmft/izpLYURRjAmm97Z8N86Ii30QM5siTy/o=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=H9RNHwURn4F9TVrLMI9zpvovJ5R8Jqn2JPWT2QB8WbMbJn11pD1vZJUtenhL+zZdg B4AvbIJuWjmRPb53zH1Kp0qAU7g9g1GheQ7KhEOYHniT9sQONL+3/AKnSmo91RF9aq zV5Al3qjDXo2bPR9Ob4+lCxNfXIXdExtSLWhuOiIqzBGmKPLtxgOvFgcB635gLgMvo DovglIz4Y5Q96tT78/Xr8f64uBtfRGVI95ylLCIivF228NRw1Er85sboSfcZgKA+8D GHFDh5MGS1oCHhmFOm+G9NgU5bsFQa5wAOd+4BJxbB0AR0/POi0G5Q3BaIPBOLd0tl CnjvPwsQNvhVA== Date: Tue, 20 Aug 2024 19:34:47 -0500 From: "Rob Herring (Arm)" To: Stephen Boyd Cc: Daniel Scally , Andy Shevchenko , Jonas Karlman , Robert Foss , Andrzej Hajda , Rob Herring , David Airlie , Maarten Lankhorst , Sakari Ailus , Douglas Anderson , Vinod Koul , Benson Leung , Dmitry Baryshkov , patches@lists.linux.dev, Heikki Krogerus , Daniel Vetter , Jernej Skrabec , Laurent Pinchart , Neil Armstrong , Prashant Malani , "Rafael J . Wysocki" , Pin-yen Lin , Krzysztof Kozlowski , Conor Dooley , linux-kernel@vger.kernel.org, Ivan Orlov , Mika Westerberg , Thomas Zimmermann , Greg Kroah-Hartman , Tzung-Bi Shih , dri-devel@lists.freedesktop.org, linux-usb@vger.kernel.org, linux-acpi@vger.kernel.org, chrome-platform@lists.linux.dev, Alexandre Belloni , Maxime Ripard , Lee Jones , devicetree@vger.kernel.org, Guenter Roeck Subject: Re: [PATCH v3 14/17] dt-bindings: usb: Add ports to google,cros-ec-typec for DP altmode Message-ID: <172420048648.2348348.16719987576551800332.robh@kernel.org> References: <20240819223834.2049862-1-swboyd@chromium.org> <20240819223834.2049862-15-swboyd@chromium.org> Precedence: bulk X-Mailing-List: chrome-platform@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240819223834.2049862-15-swboyd@chromium.org> On Mon, 19 Aug 2024 15:38:28 -0700, Stephen Boyd wrote: > Add a DT graph binding to google,cros-ec-typec so that it can combine > DisplayPort (DP) and USB SuperSpeed (SS) data into a USB type-c endpoint > that is connected to the usb-c-connector node's SS endpoint. This also > allows us to connect the DP and USB nodes in the graph to the USB type-c > connectors, providing the full picture of the USB type-c data flows in > the system. > > Allow there to be multiple typec nodes underneath the EC node so that > one DT graph exists per DP bridge. The EC is actually controlling TCPCs > and redrivers that combine the DP and USB signals together so this more > accurately reflects the hardware design without introducing yet another > DT node underneath the EC for USB type-c. > > If the type-c ports are being shared between a single DP controller then > the ports need to know about each other and determine a policy to drive > DP to one type-c port. If the type-c ports each have their own dedicated > DP controller then they're able to operate independently and enter/exit > DP altmode independently as well. We can't connect the DP controller's > endpoint to one usb-c-connector port@1 endpoint and the USB controller's > endpoint to another usb-c-connector port@1 endpoint either because the > DP muxing case would have DP connected to two usb-c-connector endpoints > which the graph binding doesn't support. > > Therefore, one typec node is required per the capabilities of the type-c > port(s) being managed. This also lets us indicate which type-c ports the > DP controller is wired to. For example, if DP was connected to ports 0 > and 2, while port 1 was connected to another DP controller we wouldn't > be able to implement that without having some other DT property to > indicate which output ports are connected to the DP endpoint. > > Cc: Rob Herring > Cc: Krzysztof Kozlowski > Cc: Conor Dooley > Cc: Lee Jones > Cc: Benson Leung > Cc: Guenter Roeck > Cc: Prashant Malani > Cc: Tzung-Bi Shih > Cc: > Cc: > Cc: Pin-yen Lin > Signed-off-by: Stephen Boyd > --- > .../bindings/mfd/google,cros-ec.yaml | 7 +- > .../bindings/usb/google,cros-ec-typec.yaml | 229 ++++++++++++++++++ > 2 files changed, 233 insertions(+), 3 deletions(-) > Reviewed-by: Rob Herring (Arm)