Chris Brown wrote:
>
> On 22/03/07, *Dave Jones* <davej(a)redhat.com <mailto:davej@redhat.com>>
> wrote:
>
> On Thu, Mar 22, 2007 at 11:15:32AM -0400, Chuck Ebbert wrote:
>
> > What are we supposed to do when this kind of thing happens? It
> appears that
> > multiple drivers claim to support the same hardware.
>
> Grr, this happens far too often. We have the same with for eg,
> orinoco and hostap right now. The usual deal is that we either
> just build the 'best' driver for that hardware, or if there's a case
> where both drivers support the same hardware _and_ some hardware unique
> to them, we nobble the pci table so that the crappier driver
> doesn't load on that hardware.
>
> As to which is the best one in this case.. I really don't know.
>
> Or maybe this is a situation where it's valid to have both drivers
> loaded?
> We don't actually support that right now, but patches went to
> linux-pci list
> last week that should be showing up in GregKHs tree adding an
> alternative
> method for drivers to bind to a device in situations where it's
> possible
> for two drivers to drive different parts of the same chip.
> (This case has been showing up more and more recently too..
> agp vs edac, matroxfb vs lm_sensors,..)
>
>
> Taking a look at:
>
>
http://lwn.net/Articles/212535/
>
> which may be able to shed some light on the changes.
Yep.
> Even with the
> blackbird driver blacklisted, the v4l2 loads but the dvb driver does
> not. It should be noted that the two co-exist peacefully when loaded but
> something is preventing the latter from loading - perhaps because the
> kernel "sees" the driver requirements as being satisfied by the v4l2
module?
>
> In any case, in this instance it is just that the cx88-dvb driver is
> failing to load as opposed to anything more sinister.
Interestingly enough, I was talking to one of the vl4-dvb maintainers
(Michael Krufky) on irc about this very driver two days ago. The
cx88-dvb driver is *supposed* to auto-load via a request_module() call
in cx8802. Similar for cx88-blackbird. Things broke when support for the
Hauppauge HVR1300 was added, because it actually needs *both* cx88-dvb
and cx88-blackbird. Upstream v4l-dvb has this fixed, verified by me from
20070302 snapshot cx88-dvb/cx8802 drivers.