[linux-dvb] RFC: remove support from v4l-dvb for kernels < 2.6.16

[Andy Walls]

On Thu, 2008-07-03 at 23:52 +0200, Hans Verkuil wrote:
> RFC: remove support from v4l-dvb for kernels < 2.6.16
> 
> After spending some time trying to get v4l-dvb to compile on older 
> kernels I discovered that:
> 
> - it is OK for kernels >= 2.6.19
> 
> - it does not compile at the moment for kernels >= 2.6.16 and < 2.6.19, 
> but that this can be fixed.
> 
> - that it can be made to compile for kernels >= 2.6.12 and < 2.6.16, 
> although quite a few drivers had to be disabled and looking at the type 
> of compile warnings emitted the result would likely crash, especially 
> the closer one gets to 2.6.12.
> 
> - that I no longer can compile against older kernels since gcc-4.1.2 no 
> longer accepts some constructions used in those kernel sources.

But a user can have an old kernel version and an old tool chain.  IMO I
don't think gcc's version is a valid criterion, as that makes an
assumption about what the user is using to build his very old kernel.

I know Fedora 5 used to include a gcc-3.2.3 (in the compat-gcc-32
package) for compiling older stuff.  I guess there was a major shift in
gcc after that point.  (I use gcc-3.2.3 in building the x86_64-mips
cross compiler tool chain for building the linux v2.4.20 firmware for my
router.) 


> I did a few scans and of the approximately 932 KERNEL_VERSION checks 
> only 268 remain if we drop support for anything below 2.6.26. That's a 
> major cleanup.

> Since it is now simply broken for anything below 2.6.19 I think it is a 
> good solution to on the one hand do a major cleanup at the expense of 
> making it unlikely that we will ever support kernels below 2.6.16, and 
> on the other hand at least start to support 2.6.16 and up.

Only supporting 2.6.26 onward would prompt a surge of questions
regarding compilation problems for users who are only a few kernel
versions behind.  I think your suggestion of supporting a few kernels
back (2.6.16 or 2.6.19) is preferable.

My $0.02

-Andy