From mboxrd@z Thu Jan 1 00:00:00 1970 From: maxime.ripard@free-electrons.com (Maxime Ripard) Date: Tue, 29 Sep 2015 21:36:44 +0200 Subject: [linux-sunxi] Re: [PATCH 5/5] ARM: sun5i: Add C.H.I.P DTS In-Reply-To: <560165EC.4050208@redhat.com> 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> <560165EC.4050208@redhat.com> Message-ID: <20150929193644.GS7104@lukather> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Tue, Sep 22, 2015 at 04:30:04PM +0200, Hans de Goede wrote: > 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. Ah, and most controllers embed that directly into the controller itself and don't rely on a GPIO to do that. Understood. Thanks! Maxime -- Maxime Ripard, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 819 bytes Desc: Digital signature URL: