lkml.org 
[lkml]   [2010]   [Apr]   [26]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: USB gadget with drivers "on board"
On Mon, 26 Apr 2010, Josua Dietze wrote:

> Michał Nazarewicz schrieb:
>
> > On Mon, 26 Apr 2010 16:16:05 +0200, Daniel Mack <daniel@caiaq.de> wrote:
> >> Are you sure they don't do exactly that by running two interfaces in
> >> the same configuration?
> >
> > Yes, I'm sure. I've investigated an USB GSM modem which, when plugged
> > for the first time reports as mass storage (single configuration, single
> > interface) and when drivers are installed as a full blown composite
> > gadget. I still haven't figured out how it does that.
>
>
> These are the notorious mode switching devices. In Windows, they
> obviously install a special storage driver doing one specific action
> on each following plugging.
> This action - some storage or control command - will "flip" the
> device, making it "disconnect" and returning as a completely different
> composite device.
>
> Storage commands used for this procedure range from "SCSI rezero" over
> "passthrough" to "SCSI eject", or involve vendor specific stuff.

I was going to say the same thing. For ease of use, I recommend using
a "SCSI eject" to trigger the mode change. That way, Linux users who
don't have the usb-modeswitch program installed can get the same effect
by running eject.

Alan Stern

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2010-04-26 21:37    [W:0.079 / U:3.196 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site