Re: Comments requested: driver for Quatech PCI serial cards

Alan Cox
2012-11-14T23:52:06Z

On Thu, 15 Nov 2012 09:40:54 +1030
Jonathan Woithe <jwoithe@just42.net> wrote:

> On Wed, Nov 14, 2012 at 12:12:22PM +0000, Alan Cox wrote:
> > > - the name of the module. Anything with "qt" in it will confuse people.
> > > I'm thinking along the lines of serial-quatech or quatech-serial:
> > > comments welcome.
> >
> > qt is fine in kernel - just be careful of the qt usb module.
>
> Ok.
>
> > I think in the same place I'd start by just adding the needed identifiers
> > to the 8250_pci driver along with any needed init helper.
>
> Is this in relation to the proposed signal routing API?

No in relation to throwing that driver away and doing it right.

> supplied by Quatech (which are not opensource unfortunately) will not be
> compatible with the new driver, necessitating the writing of new replacement
> userspace utilities.

tragedy 8)

> > As far as I can see the issues are
> >
> > 1. Clock multiplier feature
> >
> > Supportable by flags in 8250.c and worst case by providing a custom
> > set_termios. No API needed.
> >
> > 2. RS485/RS422 options
> >
> > Supportable by adding TIOCRS485 handling/callout to 8250.c (needs doing
> > anyway)
>
> Based on this, is it fair to say that the driver in its current basic form
> (clean-ups notwithstanding) cannot be considered for inclusion in mainline?

It is.

> our upcoming system. I'm guessing that the difficulties with the driver as
> it's currently structured may have been the reason it was never pushed to
> mainline by the original author in 2007.

There are not many difficulties I can see. You just add the identifiers
to the 8250_pci tables and a couple of small bits of code and everything
but the RS422/485 stuff just works.

If you need the RS422 stuff then yes its a bit more work.

Alan