USB: fix error handling in trancevibrator

trancevibrator should not pretend success if it returns an error.

Signed-off-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/usb/misc/trancevibrator.c b/drivers/usb/misc/trancevibrator.c
index 67e2fc20eeeb..03368edf3f22 100644
--- a/drivers/usb/misc/trancevibrator.c
+++ b/drivers/usb/misc/trancevibrator.c
@@ -59,13 +59,14 @@ static ssize_t set_speed(struct device *dev, struct device_attribute *attr,
 {
         struct usb_interface *intf = to_usb_interface(dev);
         struct trancevibrator *tv = usb_get_intfdata(intf);
-        int temp, retval;
+        int temp, retval, old;
 
         temp = simple_strtoul(buf, NULL, 10);
         if (temp > 255)
                 temp = 255;
         else if (temp < 0)
                 temp = 0;
+        old = tv->speed;
         tv->speed = temp;
 
         dev_dbg(&tv->udev->dev, "speed = %d\n", tv->speed);
@@ -77,6 +78,7 @@ static ssize_t set_speed(struct device *dev, struct device_attribute *attr,
                                  tv->speed, /* speed value */
                                  0, NULL, 0, USB_CTRL_GET_TIMEOUT);
         if (retval) {
+                tv->speed = old;
                 dev_dbg(&tv->udev->dev, "retval = %d\n", retval);
                 return retval;
         }