Re: [PATCH 0/3] serial: Fix support for UPF_SPD_* flags

From: Andy Shevchenko
Date: Tue Mar 22 2022 - 10:30:34 EST


On Mon, Mar 21, 2022 at 11:07 PM Pali Rohár <pali@xxxxxxxxxx> wrote:
>
> Support for UPF_SPD_* flags is currently broken in more drivers for two
> reasons. First one is that uart_update_timeout() function does not

the uart_update_timeout()

> calculate timeout for UPF_SPD_CUST flag correctly. Second reason is that
> userspace termios structre is modified by most drivers after each

structure

...

> (error handling was ommited for simplification)

omitted

> After calling set_active_spd_cust_baud() function SPD custom divisor
> should be active and therefore is_spd_cust_active() should return true.
>
> But it is not active (cfgetospeed does not return B38400) and this patch
> series should fix it. I have tested it with 8250 driver.

drivers

> Originally Johan Hovold reported that there may be issue with these
> ASYNC_SPD_FLAGS in email:
> https://lore.kernel.org/linux-serial/20211007133146.28949-1-johan@xxxxxxxxxx/
>
>
> Johan, Greg, could you please test these patches if there is not any
> regression?

I'm wondering why we are still supporting this ugly hack?
Doesn't BOTHER work for you?

I would rather expect to have this removed completely.

--
With Best Regards,
Andy Shevchenko