From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0F691C19F28 for ; Wed, 3 Aug 2022 15:57:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238083AbiHCP5v (ORCPT ); Wed, 3 Aug 2022 11:57:51 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59296 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238094AbiHCP5t (ORCPT ); Wed, 3 Aug 2022 11:57:49 -0400 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7E2465FBB; Wed, 3 Aug 2022 08:57:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1659542268; x=1691078268; h=date:from:to:cc:subject:message-id:references: mime-version:in-reply-to; bh=mOIJWP9CHMh9BXUsNu+7KhdpzZU4fbVzJUvkLwDE/es=; b=QbLDW4YmZiS65dZx1CEWrJvy79Ep5fHw6NRbMfoKG2x7kGTK7/BY9h6x 4wOzSyXCu4Yttk7YXpHABiHcQeP1ccKivAF9ajUtM2IAtaDeFTXQqgZH9 3G6wg+5dsLfVYjJk1XM6SgU1owwjSHYty/DBhKZWt1AZSAkz5zpq3cfPY PVSoQEhX5Kq6cih3ZnGk99CaHgS9i/QXq2WdNN/zyAW1JpakaRN4jV7uf aFGnNS31xAV0B5CN4q1WsBUKqH1PnqzwXMc3z6uCwp9Rlg7YZ1X1RDt/B aie24LNOk7vE8wdI3IBU83h0SnFW7qr2Etc8hZPH6p0CNzWYWcVsaoWvM g==; X-IronPort-AV: E=McAfee;i="6400,9594,10428"; a="287270048" X-IronPort-AV: E=Sophos;i="5.93,214,1654585200"; d="scan'208";a="287270048" Received: from orsmga004.jf.intel.com ([10.7.209.38]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Aug 2022 08:57:48 -0700 X-IronPort-AV: E=Sophos;i="5.93,214,1654585200"; d="scan'208";a="729250577" Received: from lahna.fi.intel.com (HELO lahna) ([10.237.72.162]) by orsmga004-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Aug 2022 08:57:44 -0700 Received: by lahna (sSMTP sendmail emulation); Wed, 03 Aug 2022 18:57:42 +0300 Date: Wed, 3 Aug 2022 18:57:42 +0300 From: Mika Westerberg To: Benson Leung Cc: Rajat Khandelwal , andreas.noever@gmail.com, michael.jamet@intel.com, YehezkelShB@gmail.com, linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, pmalani@google.com Subject: Re: [PATCH] Supporting wake on DP hot events behind TBT/USB4 routers Message-ID: References: <20220803010139.GA32634@rajth-NUC10i7FNH> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Hi Benson, On Wed, Aug 03, 2022 at 08:15:49AM -0700, Benson Leung wrote: > Hi Mika, > > On Tue, Aug 2, 2022 at 10:37 PM Mika Westerberg > wrote: > > > > Hi, > > > > On Wed, Aug 03, 2022 at 06:31:39AM +0530, Rajat Khandelwal wrote: > > > Current implementation doesn't allow user to go into system suspend > > > and simultaneously project the screen on an external display connected > > > to a TBT/USB4 device. This patch enables this feature. > > > > > > Let me know what you think about this. > > > > Please prefix patches to follow the sybsystem style. For Thunderbolt it > > should be "thunderbolt: ....". > > > > This will cause any monitor plug to wake up the system and I'm not sure > > we want that, at least to be default behaviour. If you have a regular > > Type-C (non-USB4/TBT) dock and you plug in a monitor to that, does it > > wake up? > > Speaking for Google and our ChromeOS USB-C policy, yes, if the host is > in S0iX or S3, an already attached USB-C docking station in DP Alt > Mode will respond to a display attach via HPD via an Alert message in > USB PD. We called this feature wake-on-dock. > > We implemented wake-on-dock for DP Alt Mode in the EC, since our EC > handles USB PD anyway, and is handling the PD Alert message which > contains the HPD status. > > However, when the dock supports USB4 or Thunderbolt, those modes don't > involve USB PD for device attach, so our EC doesn't have the role of > waking the system, so something else on the system must, which is this > feature being discussed. Okay understood. Thanks for explaining!