Re: Re: [PATCH v6 11/13] serial: 8250_dw: add Ambarella CV75 quirks

[Andy Shevchenko]

On Thu, Sep 10, 2026 at 05:12:52PM +0800, zl020895 wrote:

> > Wondering if we should undo this in the port's .shutdown() callback.
> I saw the shutdown path already covers it: dw8250_shutdown() calls
> serial8250_do_shutdown(), which does
> 	up->ier = 0;
> 	serial_port_out(port, UART_IER, 0);
> so both the IER shadow and hardware IER are cleared, including ETOI.

Depending on the answer to Ilpo the enabling may need an updated comment
summarising the above.

> At 2026-09-10 16:33:14, "Andy Shevchenko" <andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
> >On Fri, Sep 04, 2026 at 02:38:18PM +0800, Long Zhao via B4 Relay wrote:

...

> >> +	/*
> >> +	 * Ambarella keeps variant IER bits (e.g. ETOI) set for correct RX
> >> +	 * timeout behaviour. Force them into the 8250 IER shadow so later
> >> +	 * generic IER updates do not clear them.
> >> +	 */
> >
> >Wondering if we should undo this in the port's .shutdown() callback.

-- 
With Best Regards,
Andy Shevchenko