Re: [PATCH RFC 07/10] tty: serial: Add Cortina Systems CS75xx UART driver

[Arnd Bergmann]

On Wed, Sep 30, 2026, at 12:57, Linus Walleij wrote:
> On Wed, Sep 30, 2026 at 9:00 AM Fil Dunsky via B4 Relay
> <devnull+filipp.dunsky.gmail.com@xxxxxxxxxx> wrote:
>>
>>
>> The ports are named ttyCS so that the driver can coexist with the 8250
>> driver in multiplatform kernels, and PORT_GENERIC is used rather than
>> allocating a new port type.
>>
>> Signed-off-by: Fil Dunsky <filipp.dunsky@xxxxxxxxx>
>
> Look at this in your Linux tree:
> git log -p b61c8bf4694b5115766849378dcb8787ff54e65e
>
> This is essentially a resurrection of that driver. It was deleted again
> because it was merged prematurely. Cortina never came back to revise
> the driver. (People run out of steam. Such things happen.)

Jason actually came back this summer to try again, see
https://lore.kernel.org/linux-arm-kernel/20260610112821.3030099-1-jason.li@xxxxxxxxxxxxxxxxxx/

> Anyways, clearly this driver is not just for CS75xx so name it
> cortina-uart.c simply, and update symbols accordingly. Kconfig
> should be SERIAL_CORTINA etc.

I think we clearly want a driver that works for both the Cortina
Systems CS75xx and the Cortina Access CA82xx, hopefully that
would also support the ones inbetween (CS80xx, CA81xx).

There do seem to be a few minor differences in the register
set, but I would expect that this can be dealt with based on
the compatible string.

   Arnd