[-next] USB: cypress_m8: remove set but not used variables 'actual_size, iflag'

On Sun, Sep 30, 2018 at 06:02:24PM +0200, Johan Hovold wrote:

On Sat, Sep 29, 2018 at 09:54:03AM +0000, YueHaibing wrote:

quoted

Fixes gcc '-Wunused-but-set-variable' warning:

drivers/usb/serial/cypress_m8.c: In function 'cypress_send':
drivers/usb/serial/cypress_m8.c:689:33: warning:
 variable 'actual_size' set but not used [-Wunused-but-set-variable]

drivers/usb/serial/cypress_m8.c: In function 'cypress_set_termios':
drivers/usb/serial/cypress_m8.c:866:18: warning:
 variable 'iflag' set but not used [-Wunused-but-set-variable]

Signed-off-by: YueHaibing <redacted>
---
 drivers/usb/serial/cypress_m8.c | 11 ++---------
 1 file changed, 2 insertions(+), 9 deletions(-)

diff --git a/drivers/usb/serial/cypress_m8.c b/drivers/usb/serial/cypress_m8.c
index 31c6091..98dff12 100644
--- a/drivers/usb/serial/cypress_m8.c
+++ b/drivers/usb/serial/cypress_m8.c

@@ -686,7 +686,7 @@ static int cypress_write(struct tty_struct *tty, struct usb_serial_port *port,
 
 static void cypress_send(struct usb_serial_port *port)
 {
-	int count = 0, result, offset, actual_size;
+	int count = 0, result, offset;
 	struct cypress_private *priv = usb_get_serial_port_data(port);
 	struct device *dev = &port->dev;
 	unsigned long flags;

@@ -758,12 +758,6 @@ static void cypress_send(struct usb_serial_port *port)
 	priv->write_urb_in_use = 1;
 	spin_unlock_irqrestore(&priv->lock, flags);
 
-	if (priv->cmd_ctrl)
-		actual_size = 1;
-	else
-		actual_size = count +
-			      (priv->pkt_fmt == packet_format_1 ? 2 : 1);
-

This looks like we have a bug in the driver, and sure enough we do.
Commit 9aa8dae7b1fa ("cypress_m8: use usb_fill_int_urb where
appropriate") incorrectly started setting the transfer length to the
size of the buffer.

This is like the third time recently where we've had found a real bug.

YueHaibing, could you mention in the commit message where the variable
became unused?  It would help reviewing.  It's not a Fixes tag but it
would look like this:

    "After commit 9aa8dae7b1fa ("cypress_m8: use usb_fill_int_urb where
     appropriate") then we don't use actual_size any more so that can
     be removed."


regards,
dan carpenter