Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757944Ab3HMNSE (ORCPT ); Tue, 13 Aug 2013 09:18:04 -0400 Received: from www.linutronix.de ([62.245.132.108]:49370 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757640Ab3HMNSC (ORCPT ); Tue, 13 Aug 2013 09:18:02 -0400 Message-ID: <520A3206.5080505@linutronix.de> Date: Tue, 13 Aug 2013 15:17:58 +0200 From: Sebastian Andrzej Siewior User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130630 Icedove/17.0.7 MIME-Version: 1.0 To: Bin Liu CC: Sergei Shtylyov , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, balbi@ti.com, george.cherian@ti.com Subject: Re: [PATCH] usb: musb: am335x: Do not remove the session bin HOST-only mode References: <51F2BE6F.3010008@linutronix.de> <51F2D427.7050106@linutronix.de> <51F2DD90.2030405@linutronix.de> <20130729165329.GA5773@linutronix.de> <51F6ABA2.7060102@linutronix.de> <20130809160339.GA14829@linutronix.de> <5205516D.1030707@cogentembedded.com> <5209DCB9.8020705@linutronix.de> In-Reply-To: X-Enigmail-Version: 1.5.1 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1136 Lines: 31 On 08/13/2013 03:03 PM, Bin Liu wrote: > Sebastian, Hi Bin, >>>> + if (musb->port_mode == MUSB_PORT_MODE_HOST) { >>>> + val = USBMODE_IDDIG_A; >>>> + val |= USBMODE_ID_MUX_REG; >>> > I am going to so some tests today for this. I don't object to use the > mode register, but am wondering why we have to play with it for > host-only mode. The ID pin is grounded for host-only mode, which > should cause the same as setting mode register. I've been looking at the wiki page and it did not mention the ID pin for the second port. If it is grounded then this piece can be removed and the magic trick is just to skip the try_idle() call. I haven't found anything saying that it is required to clear the session bin in host mode, only in OTG. And then, I would assume to receive a session interrupt once we have the proper VBUS level which does not happen. > -Bin. Sebastian -- 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/