From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965521AbcBQS40 (ORCPT ); Wed, 17 Feb 2016 13:56:26 -0500 Received: from mx2.suse.de ([195.135.220.15]:33183 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965192AbcBQS4Y (ORCPT ); Wed, 17 Feb 2016 13:56:24 -0500 Message-ID: <1455735227.26846.4.camel@suse.com> Subject: Re: [PATCH 0/3] usb: USB Type-C Class and driver for UCSI From: Oliver Neukum To: Heikki Krogerus Cc: Greg KH , Felipe Balbi , Mathias Nyman , linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org Date: Wed, 17 Feb 2016 19:53:47 +0100 In-Reply-To: <1455037283-106479-1-git-send-email-heikki.krogerus@linux.intel.com> References: <1455037283-106479-1-git-send-email-heikki.krogerus@linux.intel.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.12.11 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2016-02-09 at 19:01 +0200, Heikki Krogerus wrote: > Hi, > > The OS, or more precisely the user space, needs to be able to control > a few things regarding USB Type-C ports. The first thing that must be > allowed to be controlled is the data role. USB Type-C ports will > select the data role randomly with DRP ports. When USB PD is > supported, also independent (from data role) power role swapping can > be supported together with Alternate Mode control. What about S4? We need to restore the alternate mode upon resume, if we are the DFP and as that might involve storage devices it needs to be done in kernel space. Regards Oliver