From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sarah Sharp Subject: Re: [RFC PATCH] usb/acpi: Add support usb port power off mechanism for device fixed on the motherboard Date: Fri, 11 May 2012 13:11:24 -0700 Message-ID: <20120511201124.GF18754@xanatos> References: <4FAD3A51.4010803@intel.com> <20120511183543.GF7920@kroah.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mga03.intel.com ([143.182.124.21]:59015 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754380Ab2EKULb (ORCPT ); Fri, 11 May 2012 16:11:31 -0400 Content-Disposition: inline In-Reply-To: <20120511183543.GF7920@kroah.com> Sender: linux-acpi-owner@vger.kernel.org List-Id: linux-acpi@vger.kernel.org To: Greg KH Cc: Alan Stern , Lan Tianyu , lenb@kernel.org, linux-acpi@vger.kernel.org, linux-usb@vger.kernel.org On Fri, May 11, 2012 at 11:35:43AM -0700, Greg KH wrote: > On Fri, May 11, 2012 at 01:44:26PM -0400, Alan Stern wrote: > > On Sat, 12 May 2012, Lan Tianyu wrote: > > > So I should work on the external ports without devices firstly and > > > add the sys file for user to control? > > > > Yes, I think so. It will be less controversial and probably simpler. > > When that mechanism is ready, you should be able to use it > > automatically for unconnectable ports. > > > > One tricky thing: In theory, there should be a separate sysfs file for > > each port. That seems like a lot of overhead though; is there any way > > to present the information in a single file that won't offend sysfs > > purists? > > Why is that a lot of "overhead"? It's what, 7-9 files max? As Sarah > points out, one file for all ports is racy and can get to be a mess. > > But then again, I'm a "sysfs purist" :) Theoretically there's no maximum number for xHCI root ports, so I wouldn't be so sure you'll only have 9 files on future xHCI hosts. Sarah Sharp