On 05. 12. 19, 13:30, Xiongfeng Wang wrote: > > > On 2019/12/5 20:13, Greg KH wrote: >> On Thu, Dec 05, 2019 at 08:04:36PM +0800, Xiongfeng Wang wrote: >>> Fix the following warning: >>> drivers/tty/serial/omap-serial.c: In function serial_omap_rlsi: >>> drivers/tty/serial/omap-serial.c:496:16: warning: variable ch set but not used [-Wunused-but-set-variable] >>> >>> Reported-by: Hulk Robot <hulkci@xxxxxxxxxx> >>> Signed-off-by: Xiongfeng Wang <wangxiongfeng2@xxxxxxxxxx> >>> --- >>> drivers/tty/serial/omap-serial.c | 3 +-- >>> 1 file changed, 1 insertion(+), 2 deletions(-) >>> >>> diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c >>> index 6420ae5..54ee3ae 100644 >>> --- a/drivers/tty/serial/omap-serial.c >>> +++ b/drivers/tty/serial/omap-serial.c >>> @@ -493,10 +493,9 @@ static unsigned int check_modem_status(struct uart_omap_port *up) >>> static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr) >>> { >>> unsigned int flag; >>> - unsigned char ch = 0; >>> >>> if (likely(lsr & UART_LSR_DR)) >>> - ch = serial_in(up, UART_RX); >>> + serial_in(up, UART_RX); >> >> Shouldn't you be doing something with 'ch'? > > Sorry, my original thought is trying not to modify the existing logic. > I will look into the mechanism to see if I need to check 'ch'. The change looks in fact correct, see: commit 9a12fcf8b1543c99ffcec3d61db86f0dea52dc9d Author: Shubhrajyoti D <shubhrajyoti@xxxxxx> Date: Fri Sep 21 20:07:19 2012 +0530 serial: omap: fix the reciever line error case It also says: "This is recommended in the interrupt reset method in the table 23-246 of the omap4 TRM." The character read is erroneous and should be apparently dropped. But you should add a comment about it, though. thanks, -- js suse labs