Re: Kill I4L?

From: Paul Bolle
Date: Mon Feb 09 2015 - 07:12:11 EST

On Mon, 2015-02-09 at 00:59 +0100, Karsten Keil wrote:
> Am 08.02.2015 um 20:47 schrieb Tilman Schmidt:
> > Am 07.02.2015 um 21:43 schrieb Paul Bolle:
> >> 2) Broader picture: if I remember correctly there are now four
> >> different flavors of ISDN in the kernel: - really old: pre-i4l
> >
> > I don't think any traces of that are still present in current kernel
> > releases. It should all have been left behind on the switch to 2.6.
> Yes.

I just refreshed my memory: drivers/isdn/hysdn predates I4L. It was
added in v2.3.45, while I4L was mainlined in v2.6.4. But, on the other
hand, one can optionally use HYSDN via "just old" CAPI.

(HYSDN looks a bit odd. By default "they register as ethernet card". I
guess this will only work if both ends of the ISDN connection have a
setup like that. But, who knows, maybe someone is still using HYSDN in
that way. serves "Sponsored Listings", by the way.)

> >> - very old: i4l - just old: CAPI - not so old: mISDN
> >
> > Those are the in-tree ones. To make matters worse, the Asterisk people
> > invented three more (Zaptel, DAHDI and vISDN) which are maintained
> > out-of-tree. Apparently they weren't satisfied with any the in-tree
> > ones and didn't feel like helping to improve one of them to match
> > their needs.
> >
> >> [snip] So the current ISDN situation is a bit messy.
> >
> > That's putting it mildly.
> >
> >> Tilman might be able to provide a clearer, and maybe less grumpy,
> >> summary of the current situation.
> >
> > Don't know about either. ;-)

Paul Bolle

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