From mboxrd@z Thu Jan  1 00:00:00 1970
From: ki0351.kim@samsung.com (Kyoungil Kim)
Date: Tue, 15 May 2012 20:52:39 +0900
Subject: [PATCH] serial: samsung: Fixed wrong comparison for	baudclk_rate
In-Reply-To: <20120515101541.GH10453@n2100.arm.linux.org.uk>
References: <000101cd3283$5f58eba0$1e0ac2e0$%kim@samsung.com>
 <20120515101541.GH10453@n2100.arm.linux.org.uk>
Message-ID: <000301cd3291$3a7a6940$af6f3bc0$%kim@samsung.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Russell King wrote:
> On Tue, May 15, 2012 at 07:13:28PM +0900, Kyoungil Kim wrote:
> > port->baudclk_rate should be compared to the rate of port->baudclk,
> > because port->baudclk_rate was assigned as the rate of port->baudclk previously.
> > So to check that the current baudclk rate is same as previous rate,
> > the target of comparison sholud be the rate of port->baudclk.
> >
> > Signed-off-by: Jun-Ho, Yoon <junho78.yoon@samsung.com>
> > Signed-off-by: Kyoungil Kim <ki0351.kim@samsung.com>
> > ---
> >  drivers/tty/serial/samsung.c |    4 ++--
> >  1 files changed, 2 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c
> > index d8b0aee..c4867ea 100644
> > --- a/drivers/tty/serial/samsung.c
> > +++ b/drivers/tty/serial/samsung.c
> > @@ -1014,10 +1014,10 @@ static int s3c24xx_serial_cpufreq_transition(struct notifier_block *nb,
> >  	 * a disturbance in the clock-rate over the change.
> >  	 */
> >
> > -	if (IS_ERR(port->clk))
> > +	if (IS_ERR_OR_NULL(port->baudclk))
> 
> NAK.  See my previous emails on the validity of clk_get() return values.

I read your previous emails, but I don't understand.
Could you explain more details, please?