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

From: Michal Malý
Date: Mon Jan 25 2016 - 16:02:44 EST


On Mon, 2016-01-25 at 15:17 +0100, Jiri Kosina wrote:
> On Sat, 23 Jan 2016, Michal Malà wrote:
>
> > I briefly considered leaving the switch up to the userspace and
> handling theÂ
> > device in the kernel only once it's been switched. I am however
> uncertain howÂ
> > to advertise this to the users. Writing a tiny app that would
> currently handleÂ
> > just one device seems like an overkill, abusing usb_modeswitch
> seems counter-
> > intuitive as it's purpose is to handle various USB modems.Â
>
> Well, originally usb_modeswitch (beware, it's called "modeswitch",
> notÂ
> "modemswitch" :) ) was purely for handling ZeroCD on USB 3G modems,
> andÂ
> it's currently still by far the most common case, but there are
> otherÂ
> devices being handled by that package now; I for example recall someÂ
> HP printers needing a magic USB command to be sent to it before they
> wouldÂ
> 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.

Ok, that's interesting... I tinkered with usb_modeswitch a bit and I
made it switch the G920 just fine after a while. Consider the patches
dropped then, letting usb_modeswitch take care of this sounds
reasonable.

Michal