Re: users of drivers/misc/echo ?

[Harald Welte <laforge@gnumonks.org>]

Hi Dave,

On Tue, Feb 25, 2025 at 10:04:07PM +0000, Dr. David Alan Gilbert wrote:
> * Harald Welte (laforge@gnumonks.org) wrote:
> > Hi Dave,
> > 
> > On Tue, Feb 25, 2025 at 06:39:06PM +0000, Dr. David Alan Gilbert wrote:
> > > > Actually, looking at DAHDI, I really don't think anyone is still using
> > > > the dahdi_echocan_oslec code.  It is disabled by default and only built
> > > > if explicitly enabled by the user, and indeed if anyone did that it
> > > > would fail to build for any kernels that have moved it out of staging.
> > > 
> > > It looks like Debian is including and enabling it in it's DKMS build:
> > 
> > thanks, I didn't realize that.  You could reach out to the Debian maintainer of the package
> > if you'd want clarification.
> 
> Given that Debian build etc - what's your preference?   I'm happy to
> grind a patch to remove the kernel copy if Debian is using their own copy.
> Or do we leave it and fix up Debian to use it?

I've Cc'ed Tzafrir, the Debian maintainer of the DAHDI package.  Better to ask his
opinion directly rather than speculate about it.

Tzafrir: You can read this thread on lkml.org. The summary is that mainline Linux
is considering to remove drivers/misc/echo from the kernel source, as after removal
of mISDN there are no users of it left in mainline.

DAHDI doesn't build the dahdi_echocan_oslec by default, and the
Debian dahdi-linux DKMS seems to come with its own copy/version of the actual oslec
echo cancellation code rather than using the mainline one (which has migrated from
staging to misc a decade ago).

My opinion is that there's no reason mainline should keep drivers/misc/echo.

Regards,
	Harald

-- 
- Harald Welte <laforge@gnumonks.org>          https://laforge.gnumonks.org/
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