Re: [PATCH] serial: sprd: Support 12 uart ports

[Chunyan Zhang]

On Wed, 9 Aug 2023 at 13:52, wenhua lin <wenhua.lin1994@xxxxxxxxx> wrote:
>
> The change of the max ports is to adapt to an new
> SPRD serial hardware,also is backward-compatibility with old hardware.

This change seems not backward-compatible if the serial devices on
some old Unisoc SoCs can support 8 ports only.

BTW, please do not top-post your reply.

Thanks,
Chunyan

>
> Baolin Wang <baolin.wang@xxxxxxxxxxxxxxxxx> 于2023年8月7日周一 16:41写道：
> >
> >
> >
> > On 8/7/2023 4:07 PM, Wenhua Lin wrote:
> > > From: Wenhua Lin <wenhua.lin@xxxxxxxxxx>
> > >
> > > Support 12 uart ports, which can solve the problem
> > > of insufficient uart ports.
> >
> > This sounds incorrect to me.
> > If this is a software bug, please add a Fixes tag to backport for stable
> > kernels. If the change of the max ports is only avaliable on the new
> > SPRD serial hardware, you should ensure the change is
> > backward-compatibility with old hardware.
> >
> > > Signed-off-by: Wenhua Lin <wenhua.lin@xxxxxxxxxx>
> > > ---
> > >   drivers/tty/serial/sprd_serial.c | 2 +-
> > >   1 file changed, 1 insertion(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_serial.c
> > > index b58f51296ace..2774df490899 100644
> > > --- a/drivers/tty/serial/sprd_serial.c
> > > +++ b/drivers/tty/serial/sprd_serial.c
> > > @@ -22,7 +22,7 @@
> > >   #include <linux/tty_flip.h>
> > >
> > >   /* device name */
> > > -#define UART_NR_MAX          8
> > > +#define UART_NR_MAX          12
> > >   #define SPRD_TTY_NAME               "ttyS"
> > >   #define SPRD_FIFO_SIZE              128
> > >   #define SPRD_DEF_RATE               26000000