Re: problems with usb stick after suspend and wake up

On Mon, 29 Sep 2014, Ivan Baldo wrote:

> El 29/09/14 11:15, Alan Stern escribi=F3:
> > The first error occurred the first time the computer tried to write
> > data to the stick following the resume.  Oddly enough, an earlier w=
rite
> > before the suspend worked correctly.  But the real problem occurred
> > when the computer asked the stick to provide the reason for the err=
or.
> > At that point the stick refused to answer.
> >
> > There were several resets, and the write was retried after each res=
et.
> > And each time the write failed, and the stick refused to answer whe=
n
> > asked the reason for the failure.
> >
> > There's no obvious cause for this problem.  It really looks like
> > something is wrong with the USB stick.
>      Ok the culprit is the USB stick, but when retrying and seeing th=
at=20
> the resets are unsuccessful, could the USB power be removed for the=20
> stick for half a second and restored and the write retried then?

The simple answer is No.  Host USB controllers often are not capable of=
=20
turning off USB power.

Besides, what would happen if the device were not a stick but a disk=20
drive with an external power supply?

Alan Stern

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