From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758033AbbIVOaK (ORCPT ); Tue, 22 Sep 2015 10:30:10 -0400 Received: from mx1.redhat.com ([209.132.183.28]:38470 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755491AbbIVOaI (ORCPT ); Tue, 22 Sep 2015 10:30:08 -0400 Subject: Re: [linux-sunxi] Re: [PATCH 5/5] ARM: sun5i: Add C.H.I.P DTS To: Maxime Ripard References: <1442566130-3497-1-git-send-email-maxime.ripard@free-electrons.com> <1442566130-3497-6-git-send-email-maxime.ripard@free-electrons.com> <20150922124708.GZ4684@lukather> <56015146.2070509@redhat.com> <20150922140424.GA4684@lukather> Cc: Chen-Yu Tsai , Mike Turquette , Stephen Boyd , linux-arm-kernel , linux-clk , linux-kernel , linux-sunxi From: Hans de Goede Message-ID: <560165EC.4050208@redhat.com> Date: Tue, 22 Sep 2015 16:30:04 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.2.0 MIME-Version: 1.0 In-Reply-To: <20150922140424.GA4684@lukather> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 22-09-15 16:04, Maxime Ripard wrote: > On Tue, Sep 22, 2015 at 03:01:58PM +0200, Hans de Goede wrote: >>> In short, this is not about "power supply" but VBUS detection. IIRC, >>> if no VBUS detection method is provided, the phy driver just waits a >>> period of time after an ID pin change and then considers VBUS invalid. >> >> Right, but that is a hack for boards with no / broken vbus detection >> (or vbus control), we really want to use vbus-det where available, >> so I agree that a TODO comment here would be good. > > What's so special in our SoCs that makes that we can't just rely on > the ID pin ? (which seems to be working just fine here) There is nothing special, AFAIK all OTG ports (also for other SoCs) have some sort of vbus detection mechanism. We need the hack because vbus-det is broken on some of our boards. And where it is not broken we should be using vbus-det normallu. Regards, Hans