Re: [PATCH] USB: add Sensoray 2255 v4l driver

From: Oliver Neukum
Date: Thu May 15 2008 - 16:14:20 EST


Am Donnerstag 15 Mai 2008 22:10:49 schrieb Greg KH:
> On Thu, May 15, 2008 at 09:54:12PM +0200, Oliver Neukum wrote:
> > Am Donnerstag 15 Mai 2008 20:44:24 schrieb Greg KH:
> > > On Thu, May 15, 2008 at 02:03:18PM +0200, Oliver Neukum wrote:
> > > > Am Donnerstag 15 Mai 2008 13:38:37 schrieb Oliver Neukum:
> > > > > 3. The firmware stuff. That's an interesting solution. However:
> > > >
> > > > Actually, on second thought, I take that back. It's a bad solution.
> > > > If you don't want to do it in probe(), the only other sensible place
> > > > is in open(). That way you can avoid the whole trouble if nobody
> > > > opens the device. And you need to handle the case of unloaded
> > > > firmware anyway, so you can trigger firmware load there.
> > >
> > > No, we want to do firmware load on probe, I'll change it to be async so
> >
> > Could you state your reasons for that preference?
>
> I don't want to create the device nodes, and have userspace think the
> device really is working, only to have everything fall down and die if
> open() is called and the firmware isn't present. I'd rather not create
> the video devices if we know this isn't going to work at all.

Yes, that makes sense. However, then you might want to look into
spawning a thread per bus rather than a delayed failure mechanism.

Regards
Oliver


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