Re: [patch] video: build fix for drivers/media/video/pvrusb2/

[Mike Isely <isely@isely.net>]

On Tue, 13 May 2008, Mike Isely wrote:

> On Tue, 13 May 2008, Mauro Carvalho Chehab wrote:
> 
> > On Tue, 13 May 2008 00:03:02 -0400
> > "Michael Krufky" <mkrufky@linuxtv.org> wrote:
> > 
> > > 
> > > That sounds like it would be OK, although something like this would
> > > probably be better:
> > > 
> > >  config VIDEO_PVRUSB2
> > >        tristate "Hauppauge WinTV-PVR USB2 support"
> > > -       depends on VIDEO_V4L2 && I2C
> > > +       depends on VIDEO_V4L2 && I2C && (DVB_CORE if VIDEO_PVRUSB2_DVB)
> > >        select FW_LOADER
> > >        select MEDIA_TUNER
> > >        select VIDEO_TVEEPROM
> > 
> > This doesn't look to be a good idea, since VIDEO_PVRUSB2_DVB depends on
> > VIDEO_PVRUSB2. So, you'll create a circular dependency. The syntax I've
> > proposed seems cleaner. Of course, it needs to be tested. IMO, all hybrid
> > devices should be dependent of VIDEO_MEDIA. This will help to avoid this kind
> > of issue.
> > 
> > > I don't know if that syntax works for "depends on" , but it does work
> > > for select.
> > > 
> > > if "depends on FOO if BAR" doesnt work, would adding "select DVB_CORE
> > > if VIDEO_PVRUSB2_DVB" solve the problem?
> > 
> > Also, this leads into a circular reference.
> 
> Mauro:
> 
> Where is the loop that results in a circular reference?  No part of V4L 
> or DVB depends (or otherwise has any reliance) on VIDEO_PVRUSB2.  All 
> Mike Krufky is trying to set up is that VIDEO_PVRUSB2 should only depend 
> on DVB_CORE if the DVB part of the driver (i.e. VIDEO_PVRUSB2_DVB) has 
> been enabled.  Without VIDEO_PVRUSB2_DVB selected, then DVB_CORE is not 
> required by the driver.
> 
> I've been quiet about this issue because I'm not a kconfig expert, but 
> you've lost me with this conclusion.
> 
>   -Mike

Never mind.  I think I see it, and will figure out the rest off-line.

  -Mike

-- 

Mike Isely
isely @ pobox (dot) com
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