[PATCH v3] serial: PL011: clear pending interrupts

[Chanho Min]

On Tue, Mar 13, 2012 at 9:27 PM, Linus Walleij
<linus.walleij at stericsson.com> wrote:
> From: Linus Walleij <linus.walleij at linaro.org>
>
> Chanho Min reported that when the boot loader transfers
> control to the kernel, there may be pending interrupts
> causing the UART to lock up in an eternal loop trying to
> pick tokens from the FIFO (since the RX interrupt flag
> indicates there are tokens) while in practice there are
> no tokens - in fact there is only a pending IRQ flag.
>
> This patch address the issue with a combination of two
> patches suggested by Russell King that clears and mask
> all interrupts at probe() and clears any pending error
> and RX interrupts at port startup time.
>
> We suspect the spurious interrupts are a side-effect of
> switching the UART from FIFO to non-FIFO mode.
I've tested this patch, and have confirmed that the issue is resolved
on our CA9 platform.
In addition, May I ask to change the tag as follows.

Reported-by: Chanho Min <chanho.min at lge.com>
Reviewed-by: Jong-Sung Kim <neidhard.kim at lge.com>

Thanks a lot !
Chanho Min