Re: [PATCH 2/2] serial: Airoha SoC UART and HSUART support

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Jan 06, 2025 at 01:35:10PM +0100, Benjamin Larsson wrote:
> Hi.
> 
> > > > > diff --git a/include/uapi/linux/serial_core.h b/include/uapi/linux/serial_core.h
> > > > > index 9c007a106330..c71fb338accb 100644
> > > > > --- a/include/uapi/linux/serial_core.h
> > > > > +++ b/include/uapi/linux/serial_core.h
> > > > > @@ -231,6 +231,12 @@
> > > > >    /* Sunplus UART */
> > > > >    #define PORT_SUNPLUS 123
> > > > > 
> > > > > +/* Airoha UART */
> > > > > +#define PORT_AIROHA  124
> > > > > +
> > > > > +/* Airoha HSUART */
> > > > > +#define PORT_AIROHA_HS       125
> > > > 
> > > > Do you REALLY need these port definitions in userspace?  If so, what is
> > > > going to use them there?
> > > > 
> > > 
> > > Testing another PORT define gives this result:
> > > 
> > > grep -ri PORT_MTK_BTIF *
> > > 
> > > drivers/tty/serial/8250/8250_of.c:            .data = (void *)PORT_MTK_BTIF, },
> > > drivers/tty/serial/8250/8250_port.c:  [PORT_MTK_BTIF] = {
> > > include/uapi/linux/serial_core.h:#define PORT_MTK_BTIF        117
> > > 
> > > Per my understanding this is how the current code is designed to work.
> > 
> > That's a very old pattern, I'm asking you if you need this new number in
> > userspace, which is what you are doing here.  I'd prefer not to add new
> > values here as they are a pain to manage and we can never change them if
> > added.
> > 
> 
> I dont need it in userspace. I need it in serial8250_config uart_config[]
> that uses this header.

Then use something internal to the kernel please, and not exported to
userspace where it must never change for the next 50+ years :(

thanks,

greg k-h