USB and suspend. Will it still charge?

Carsten Haitzler (The Rasterman) raster at
Wed Apr 23 06:26:45 CEST 2008

On Tue, 22 Apr 2008 15:42:36 +0100 Andy Green <andy at> babbled:

> Hash: SHA1
> Somebody in the thread at some point said:
> | This afternoon I recognized my laptop throwing a note about "USB device
> | detached" when Freerunner goes suspend.
> | Raster knows, at least Windows definitely will power down the
> USB-connector
> | when it sees USB-disconnect.
> |
> | Maybe we should investigate this, and should clock down the CPU and
> shut off
> | LCM, but not go to suspend while charging.
> | I should mention I'm not even sure Freerunner did charge at all at this
> | moment, just in case this makes a difference.
> What's the actual concern there?  If it is to do with missing charging
> state change, the PMU throws an interrupt to the CPU on USB connector
> insertion and removal, AFAIK these will cause wake.

concern is:

we plug in, phone wakes. phone gets bored. phone goes to sleep. uspend happens.
pc detects device removal. pc powers down usb port. phone does not have power
from usb. no charging happens.


Carsten Haitzler (The Rasterman) <raster at>

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