Subject: Re: Blackberry Curve, USB, and NetBSD?
To: John Nemeth <>
From: Manuel Bouyer <>
List: tech-kern
Date: 09/28/2007 20:00:18
On Fri, Sep 28, 2007 at 07:47:14AM -0700, John Nemeth wrote:
>      There are plenty of things that draw power such as little fans and
> lights which don't have any electronics at all.  Although, I guess it
> is possible that these devices are playing fast and loose with the
> specs.

I don't remember the exact value, but a device is allocated limited power
when first plugged into the USB port, which may not be enough for
charging. Once it has identified to the host
and said how much power it needs (or, eventually, sent the power
requirements for different PM modes), the host can budget the power and
return to the device how much it can get from the USB power supply.

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference