Re: [PATCH 0/2] Add a skeleton module to perform a basic initialization on certain USB devices

From: Jiri Kosina
Date: Mon Jan 25 2016 - 09:17:17 EST

On Sat, 23 Jan 2016, Michal Malý wrote:

> I briefly considered leaving the switch up to the userspace and handling the
> device in the kernel only once it's been switched. I am however uncertain how
> to advertise this to the users. Writing a tiny app that would currently handle
> just one device seems like an overkill, abusing usb_modeswitch seems counter-
> intuitive as it's purpose is to handle various USB modems.

Well, originally usb_modeswitch (beware, it's called "modeswitch", not
"modemswitch" :) ) was purely for handling ZeroCD on USB 3G modems, and
it's currently still by far the most common case, but there are other
devices being handled by that package now; I for example recall some
HP printers needing a magic USB command to be sent to it before they would
start printing, and usb_modeswitch is handling those now AFAIK.

So if we do this in userspace, I think usb_modeswitch is not a bad choice.


Jiri Kosina