From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kukjin Kim Subject: RE: [PATCH v2] serial: samsung: Fixed wrong comparison for baudclk_rate Date: Thu, 17 May 2012 15:55:03 +0900 Message-ID: <0b1f01cd33f9$fc9503f0$f5bf0bd0$%kim@samsung.com> References: <000501cd3297$75fba910$61f2fb30$%kim@samsung.com> <20120515124538.GN10453@n2100.arm.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Return-path: In-reply-to: <20120515124538.GN10453@n2100.arm.linux.org.uk> Content-language: ko Sender: linux-samsung-soc-owner@vger.kernel.org To: 'Russell King - ARM Linux' , 'Kyoungil Kim' Cc: linux-arm-kernel@lists.infradead.org, linux-serial@vger.kernel.org, linux-samsung-soc@vger.kernel.org, 'Jun-Ho Yoon' , 'Alan Cox' List-Id: linux-serial@vger.kernel.org Russell King - ARM Linux wrote: > > On Tue, May 15, 2012 at 09:37:16PM +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 > > Signed-off-by: Kyoungil Kim > > --- > > 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..6a6a86a 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(port->baudclk) || port->baudclk == NULL) > > Still no. Why are you wanting to detect a NULL baud clock? > > As I said, drivers have no business interpreting anything but IS_ERR(clk) > as being an error. They should not make any other assumptions. > > Now that I look at this driver, it makes this mistake all over the place. > This needs to be fixed. Something like the below should do it. Please > check. > Russell, thanks for your kindly pointing out. Kyoungil, could you please re-submit for this as per Russell's suggestion (with Russell's patch)? Thanks. Best regards, Kgene. -- Kukjin Kim , Senior Engineer, SW Solution Development Team, Samsung Electronics Co., Ltd. > diff --git a/drivers/tty/serial/samsung.c b/drivers/tty/serial/samsung.c > index d8b0aee..6a952b1 100644 > --- a/drivers/tty/serial/samsung.c > +++ b/drivers/tty/serial/samsung.c > @@ -529,7 +529,7 @@ static void s3c24xx_serial_pm(struct uart_port *port, > unsigned int level, > > switch (level) { > case 3: > - if (!IS_ERR(ourport->baudclk) && ourport->baudclk != NULL) > + if (!IS_ERR(ourport->baudclk)) > clk_disable(ourport->baudclk); > > clk_disable(ourport->clk); > @@ -538,7 +538,7 @@ static void s3c24xx_serial_pm(struct uart_port *port, > unsigned int level, > case 0: > clk_enable(ourport->clk); > > - if (!IS_ERR(ourport->baudclk) && ourport->baudclk != NULL) > + if (!IS_ERR(ourport->baudclk)) > clk_enable(ourport->baudclk); > > break; > @@ -713,9 +713,9 @@ static void s3c24xx_serial_set_termios(struct > uart_port *port, > if (ourport->baudclk != clk) { > s3c24xx_serial_setsource(port, clk_sel); > > - if (ourport->baudclk != NULL && !IS_ERR(ourport->baudclk)) { > + if (!IS_ERR(ourport->baudclk)) { > clk_disable(ourport->baudclk); > - ourport->baudclk = NULL; > + ourport->baudclk = ERR_PTR(-EINVAL); > } > > clk_enable(clk); > @@ -1160,6 +1160,9 @@ static ssize_t s3c24xx_serial_show_clksrc(struct > device *dev, > struct uart_port *port = s3c24xx_dev_to_port(dev); > struct s3c24xx_uart_port *ourport = to_ourport(port); > > + if (IS_ERR(ourport->baudclk)) > + return -EINVAL; > + > return snprintf(buf, PAGE_SIZE, "* %s\n", ourport->baudclk->name); > } > > @@ -1200,6 +1203,7 @@ static int s3c24xx_serial_probe(struct > platform_device *pdev) > return -ENODEV; > } > > + ourport->baudclk = ERR_PTR(-EINVAL); > ourport->info = ourport->drv_data->info; > ourport->cfg = (pdev->dev.platform_data) ? > (struct s3c2410_uartcfg *)pdev->dev.platform_data :