USB power direction in host mode (was: Re: 3G USB Dongle (was Re: Neo as cellular modem?))

[Michael Shiloh]

Andy Green wrote:
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> Somebody in the thread at some point said:
> | Am Mi  28. Mai 2008 schrieb Brad Midgley:
> |> Joerg
> |>
> |> On Wed, May 28, 2008 at 2:30 AM, Joerg Reisenweber <joerg at openmoko.org>
> | wrote:
> |>> Am Mi  28. Mai 2008 schrieb Brad Midgley:
> |>>> i think it may still be up in the air
> |>> Nope it's not, see Y-cable in wiki. Should work perfectly. You just
> have
> | to
> |>> find the 5pin-mini-USB-plug to DIY one.
> |> is EN_USBHOST is deasserted by the system automatically now? I'll
> |> update the section in
> |> http://wiki.openmoko.org/wiki/Neo_FreeRunner_GTA02_Hardware if it is.
> |
> | No idea, it's a driver issue. On detection of 47k device is switching to
> | fastcharge, which I think is actually working. Also it should activate
> | LOGICAL hostmode for USB-controller same time (NOT asserting
> EN_USBHOST!),
> | which is needed for Y-Cable and doesn't hurt charger. I don't have the
> | slightest idea whether this already is in kernel or not.
> 
> It is deasserted if it sees you have a 1A charger in there, has been for
> a while.

A related question: I presume that it is the electrical signal 
EN_USBHOST which flips the switch which causes the USB port to source 
current in host mode, as opposed to sinking current in device mode.

This is of course what is expected of a USB host, but it also prevents 
us from charging the Freerunner when the USB port is in host mode, if an 
appropriate power source is available.

Question:
Is it possible to charge the Neo Freerunner when using the USB port in 
host mode, by ascerting LOGICAL hostmode and by NOT asserting EN_USBHOST?