Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756269Ab3GQPhi (ORCPT ); Wed, 17 Jul 2013 11:37:38 -0400 Received: from iolanthe.rowland.org ([192.131.102.54]:42280 "HELO iolanthe.rowland.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1756147Ab3GQPhg (ORCPT ); Wed, 17 Jul 2013 11:37:36 -0400 Date: Wed, 17 Jul 2013 11:37:35 -0400 (EDT) From: Alan Stern X-X-Sender: stern@iolanthe.rowland.org To: Felipe Balbi cc: Rong Wang , Greg KH , Arnd Bergmann , , , Subject: Re: [PATCH] usb: udc: add gadget state kobject uevent In-Reply-To: <20130717132736.GA7614@arwen.pp.htv.fi> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1720 Lines: 44 On Wed, 17 Jul 2013, Felipe Balbi wrote: > On Wed, Jul 17, 2013 at 09:04:54PM +0800, Rong Wang wrote: > > Hi Felipe, > > > > On Wed, Jul 17, 2013 at 3:57 PM, Felipe Balbi wrote: > > > Hi, > > > > > > On Mon, Jul 15, 2013 at 11:31:17PM -0700, Greg KH wrote: > > >> > The question is since we default GADGET, so the g_mass_storage.ko is > > >> > installed early but connecting to a host PC > > >> > is randomly, But the udev has no idea when a host PC connects our device. > > >> > > > >> > So we consider it's reasonable to let the udev know the GADGET device state. > > >> > Is there any alternative to our question? > > >> > > >> I thought we already export events for gadget device states, have you > > >> looked for them? I can't dig through the code at the moment, but this > > >> seems like a pretty common issue... > > >> > > >> Felipe, any ideas? > > > > > > we already expose that in sysfs. IIRC udev can act on sysfs changes, > > > no ? > > > > I do not know if udev can polling sysfs file content change. I'll study this. > > > > But the change is triggered by calling usb_gadget_set_state, and I find > > composite framework do not call this. Then we should do this common work > > in every udc driver? > > yes. Only the UDC driver knows when the controller is moving among those > states. Not quite. Only the gadget driver knows when the transition between ADDRESS and CONFIGURED occurs. This should be added to composite.c. Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/