From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964793Ab3GCNGt (ORCPT ); Wed, 3 Jul 2013 09:06:49 -0400 Received: from devils.ext.ti.com ([198.47.26.153]:56792 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753804Ab3GCNGr (ORCPT ); Wed, 3 Jul 2013 09:06:47 -0400 Message-ID: <51D421BC.9050600@ti.com> Date: Wed, 3 Jul 2013 16:06:04 +0300 From: Roger Quadros User-Agent: Mozilla/5.0 (X11; Linux i686; rv:16.0) Gecko/20121011 Thunderbird/16.0.1 MIME-Version: 1.0 To: CC: Alan Stern , , , , , , Subject: Re: [RFC PATCH 4/6] USB: ehci-omap: Suspend the controller during bus suspend References: <51D28DB9.704@ti.com> <20130703125719.GD15056@arwen.pp.htv.fi> In-Reply-To: <20130703125719.GD15056@arwen.pp.htv.fi> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/03/2013 03:57 PM, Felipe Balbi wrote: > Hi, > > On Tue, Jul 02, 2013 at 01:17:58PM -0400, Alan Stern wrote: >> A PCI-based EHCI controller has two power sources: the core well (which >> is turned off during suspend) and the auxiliary well (which remains >> powered). That's how remote wakeup works; it uses the auxiliary well. > > This, kinda, matches what OMAP tries to do with pad wakeup. Just that > pad wakeup sits outside of the device itself. Perhaps we could look into > how PCI handles the aux well and take some inspiration from there. > > Any pointers under drivers/pci/ would be great :-) > >>From what I understood, auxiliary well is just a power source, and it keeps the EHCI controller powered even during suspend. If that is true then it is different from our situation as we power down the EHCI controller completely. cheers, -roger