Re: [PATCH v4 2/5] serial/8250: Use the cache value of the FCR register

From: Ilpo Järvinen
Date: Thu Mar 17 2022 - 04:29:57 EST


On Wed, 16 Mar 2022, Wander Lairson Costa wrote:

> commit 5021d709b31b ("tty: serial: Use fifo in 8250 console driver")
> erroneous tries to read the FCR register content, but this register is
> write-only.
>
> This patch fixes that by reading the content from the port struct fcr
> field.
>
> Thanks to Jon Hunter and Jiri Slaby.
>
> Suggested-by: Jiri Slaby <jirislaby@xxxxxxxxxx>
> Reported-by: Jon Hunter <jonathanh@xxxxxxxxxx>
> Signed-off-by: Wander Lairson Costa <wander@xxxxxxxxxx>
> ---
> drivers/tty/serial/8250/8250_port.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/tty/serial/8250/8250_port.c b/drivers/tty/serial/8250/8250_port.c
> index 2abb3de11a48..9f3fa9fe2a4e 100644
> --- a/drivers/tty/serial/8250/8250_port.c
> +++ b/drivers/tty/serial/8250/8250_port.c
> @@ -3410,7 +3410,7 @@ void serial8250_console_write(struct uart_8250_port *up, const char *s,
>
> use_fifo = (up->capabilities & UART_CAP_FIFO) &&
> port->fifosize > 1 &&
> - (serial_port_in(port, UART_FCR) & UART_FCR_ENABLE_FIFO) &&
> + (up->fcr & UART_FCR_ENABLE_FIFO) &&

Didn't you just add this line in 1/5? Please merge this kind of fixes that
are due to development history of a change to the main patch itself.


--
i.