From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: [PATCH] mfd: twl4030-power: Fix poweroff with PM configuration enabled Date: Fri, 21 Nov 2014 15:37:10 -0800 Message-ID: <20141121233709.GA7046@atomide.com> References: <20141102180756.GH31454@atomide.com> <5458D29E.50908@compulab.co.il> <20141104154231.GP31454@atomide.com> <515E660B-B65D-41EF-97F5-74E4DE8FDD13@goldelico.com> <20141112212027.GK26481@atomide.com> <20141112223154.GP641@saruman> <20141119144348.169c4166@notabene.brown> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20141119144348.169c4166@notabene.brown> Sender: linux-kernel-owner@vger.kernel.org To: NeilBrown Cc: Felipe Balbi , "Dr. H. Nikolaus Schaller" , Grazvydas Ignotas , Igor Grinberg , Lee Jones , Samuel Ortiz , Russell King - ARM Linux , "linux-kernel@vger.kernel.org" , "linux-omap@vger.kernel.org" , List for communicating with real GTA04 owners List-Id: linux-omap@vger.kernel.org * NeilBrown [141118 19:45]: > On Wed, 12 Nov 2014 16:31:54 -0600 Felipe Balbi wrote: > > > > this is actually what the USB Battery Charging spec requires us to > > implement. If Linux is doing differently, it's a bug on Linux which > > should be fixed :-) > > > > No host is allowed to source more then one unit load (100mA in LS/FS/HS, > > 150mA in SS) until the device is fully enumerated. Host are also > > required to drop max current budget to 8mA (IIRC) if the device doesn't > > enumerate for however many minutes (I guess it was a pretty long > > threshold, something like half an hour or so. My memory fails me right > > now). > > > > I think the twl4030 driver does do the "right" thing unless the "allow_usb" > module parameter is set, in which case it enables charging at a higher rate > which is 600mA (default value of BCIIREF1). > > It would be nice if the driver could check if a charger was plugged in and > act accordingly. > The charger I have for my openmoko is identified by a 47K resistor between ID > and ground. The twl4030 can detect that easily enough, but it isn't very > standard. Sounds doable to me, feel free to patch it up since you guys are using the twl4030 charger :) > The standard is of course to have D+ and D- shorted, but I don't know if the > twl4030 can detect that? If it can, then getting some very early code to > check for the short (or the 47k resistor) and quickly enabling charging might > be a sufficient solution. I guess. Note that there's also the USB BC1.2 spec that is more complicated than having the data lines shorted. Regards, Tony