RE: [PATCH] Clear previous interrupts after fifo is disabled

["Kim, Jong-Sung" <neidhard.kim@lge.com>]

> -----Original Message-----
> From: Chanho Min [mailto:chanho0207@gmail.com]
> Sent: Saturday, March 10, 2012 11:15 AM
> To: Greg Kroah-Hartman
> Cc: Linus Walleij; Russell King; Alan Cox; Shreshtha Kumar Sahu; Kim,
Jong-
> Sung; linux-kernel@vger.kernel.org; linux-serial@vger.kernel.org
> Subject: Re: [PATCH] Clear previous interrupts after fifo is disabled
> 
> >> To me it seems Russell's patch solves part of the problem, and
> >> Jong-Sung Kim's patch on top of that solves the entire problem, but
> >> Chanho need to come back and tell whether this is the case in
> >> practice.
> >
> > Ok, then, once it is tested, can someone resend them to me?
> >
> > thanks,
> >
> > greg k-h
> 
> I checked that Jong-Sung Kim's patch solved this hang-up issue and agree
on
> it. But, RTIS seems to be cleared as well.

You're right. RTIS should be cleared as well as RXIS. Revised patch:

diff --git a/drivers/tty/serial/amba-pl011.c
b/drivers/tty/serial/amba-pl011.c
index 6800f5f..39520db 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c
@@ -224,6 +224,11 @@ static int pl011_fifo_to_tty(struct uart_amba_port
*uap)
 		uart_insert_char(&uap->port, ch, UART011_DR_OE, ch, flag);
 	}
 
+	/* RTIS and/or RXIS, but RXFE? Just clear the interrupt(s) */
+	if(unlikely(fifotaken == 0))
+		writew(UART011_RTIS | UART011_RXIS, uap->port.membase +
+		       UART011_ICR);
+
 	return fifotaken;
 }