[PATCH 05/18] tty: serial: samsung_tty: add support for Apple UARTs

[Greg Kroah-Hartman]

On Tue, Feb 09, 2021 at 01:18:21AM +0900, Hector Martin wrote:
> On 08/02/2021 19.34, Marc Zyngier wrote:
> > On 2021-02-07 09:12, Hector Martin 'marcan' wrote:
> > > On 06/02/2021 22.15, Marc Zyngier wrote:
> > > > Do you actually need a new port type here? Looking at the driver
> > > > itself, it is mainly used to work out the IRQ model. Maybe introducing
> > > > a new irq_type field in the port structure would be better than
> > > > exposing this to userspace (which should see something that is exactly
> > > > the same as a S3C UART).
> > > 
> > > Well... every S3C variant already has its own port type here.
> > > 
> > > #define PORT_S3C2410    55
> > > #define PORT_S3C2440    61
> > > #define PORT_S3C2400    67
> > > #define PORT_S3C2412    73
> > > #define PORT_S3C6400    84
> > > 
> > > If we don't introduce a new one, which one should we pretend to be? :)
> > 
> > Pick one! :D
> 
> *queries /dev/urandom* :-)
> 
> > > I agree that it might make sense to merge all of these into one,
> > > though; I don't know what the original reason for splitting them out
> > > is. But now that they're part of the userspace API, this might not be
> > > a good idea. Though, unsurprisingly, some googling suggests there are
> > > zero users of these defines in userspace.
> > 
> > I don't think we can do that, but I don't think we should keep adding
> > to this unless there is a very good reason. Greg would know, I expect.
> 
> Greg, what do you think? Add more PORT_ UART types for Samsung variants, or
> overload one of the existing ones and deal with it in the driver?

I HATE adding new PORT_ types, as I am almost positive no one uses them,
but as they are in the uapi files, we can't delete them.

So, just use an existing one, why do you want a new one?  If you don't
have a userspace tool that requires it, don't bother.

Just use PORT_8250 and be done with it.  I should force all new drivers
to use that as well :)

thanks,

greg k-h