Re: [RFC/PATCH 1/5] usb: otg: add notifier support

From: Felipe Balbi
Date: Tue Jan 26 2010 - 13:52:41 EST

On Tue, Jan 26, 2010 at 04:21:28PM +0100, ext David Brownell wrote:
On Tuesday 26 January 2010, Felipe Balbi wrote:
>Thing is, supplying current is a bit more involved.  If the
>board can't supply 300 mA, the USB configuration selection
>mechanism has to know that, so it never selects peripheral
>configurations which require that much current.

but that's done already by the usb core, no ? It rules out configuration
based on the hub->power_budget (can't remember if the field is that
exact name).

Yes, it handles that ... but where does the power budget
come from? That's what I meant by "more involved".

we set it from board-files (on ARM, at least). It's a board characteristic, no ?

As in, the host/supplying side of the power equation can't
be event driven like the peripheral/consuming side can.

And that's another reason I think it's best to fully solve
the common (peripheral, recharge-that-batter) case first.

fair enough.

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