Re: [linux-usb-devel] Problems with USB disk [solved]

Alan Stern
2007-09-13T15:09:30Z

On Thu, 13 Sep 2007, Mark Lord wrote:

> Alan Stern wrote:
> > On Wed, 12 Sep 2007, Mark Lord wrote:
> >
> >> Chuck Ebbert wrote:
> ..
> >>> Oh, nice. The usb-storage (SCSI) disk spins itself down and we can't handle that.
> >>> Should we be disabling auto-spindown when we connect the device, or be able to
> >>> handle this by sending the start command when needed?
> >> There's more to this.
> >>
> >> My Sandisk Cruzer Micro 1GB USB sticks suffer from this regression.
> >
> > I seriously doubt that. Are you claiming that your USB stick spins
> > itself down during a suspend? And then requires to be spun back up
> > before it will resume proper operation?
>
> No, the machine is not being suspended at all.
>
> What happens is, there's a nice little LED on the Cruzer stick,
> that is "lit" when the stick itself is not in a "power suspend" state
> (or whatever you USB folks call it).

We call it "suspended". (Wasn't there an episode of Classic Trek where
Mr. Spock explained to somebody, "I call them `ears'."?)

> On 2.6.22, that little LED stays "on" normally, and flickers off/on
> when data is being transfered.
>
> The new "USB autosuspend" logic in 2.6.23 now causes that little LED
> to turn off after a few seconds of inactivity.
>
> Once that happens, the USB stick is not accessible until after a longish
> timeout (~30s I think), followed by a USB reset. Then it is usable again
> until the next inactivity timeout and autosuspend (a few seconds).

So this _isn't_ the regression described above -- to wit, that the
drive gets spun down and then won't work without first being spun back
up. You wrote:

> >> My Sandisk Cruzer Micro 1GB USB sticks suffer from this regression.

But it doesn't. It suffers from a different regression.

Alan Stern