do_command() may fail. The fix adds the missed return value of
do_command(). If it fails, returns its error code.
Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
                }
                if (sd->params.qx3.button) {
                        /* button pressed - unlock the latch */
-                       do_command(gspca_dev, CPIA_COMMAND_WriteMCPort,
+                       ret = do_command(gspca_dev, CPIA_COMMAND_WriteMCPort,
                                   3, 0xdf, 0xdf, 0);
-                       do_command(gspca_dev, CPIA_COMMAND_WriteMCPort,
+                       if (ret)
+                               return ret;
+                       ret = do_command(gspca_dev, CPIA_COMMAND_WriteMCPort,
                                   3, 0xff, 0xff, 0);
+                       if (ret)
+                               return ret;
                }
 
                /* test whether microscope is cradled */