Re: [PATCH] serial: lantiq: add missing interrupt ack

[Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>]

On Fri, 2 Jun 2023, Bernhard Seibold wrote:

> Currently, the error interrupt is never acknowledged, so once active it
> will stay active indefinitely, causing the handler to be called in an
> infinite loop.
> 
> Fixes: 2f0fc4159a6a ("SERIAL: Lantiq: Add driver for MIPS Lantiq SOCs.")
> Cc: <stable@xxxxxxxxxxxxxxx>
> Signed-off-by: Bernhard Seibold <mail@xxxxxxxxxxxxxxxxxxx>
> ---
>  drivers/tty/serial/lantiq.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/tty/serial/lantiq.c b/drivers/tty/serial/lantiq.c
> index a58e9277dfad..f1387f1024db 100644
> --- a/drivers/tty/serial/lantiq.c
> +++ b/drivers/tty/serial/lantiq.c
> @@ -250,6 +250,7 @@ lqasc_err_int(int irq, void *_port)
>  	struct ltq_uart_port *ltq_port = to_ltq_uart_port(port);
>  
>  	spin_lock_irqsave(&ltq_port->lock, flags);
> +	__raw_writel(ASC_IRNCR_EIR, port->membase + LTQ_ASC_IRNCR);
>  	/* clear any pending interrupts */
>  	asc_update_bits(0, ASCWHBSTATE_CLRPE | ASCWHBSTATE_CLRFE |
>  		ASCWHBSTATE_CLRROE, port->membase + LTQ_ASC_WHBSTATE);

Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx>

This has been there since the beginning, it is a bit odd if nobody has hit 
this before now.

-- 
 i.