Kernel version 2.6.13 introduced a regression in the generic USB
serial converter driver (usbserial.o, drivers/usb/serial/generic.c).
The bug manifests, as far as I can tell, whenever you attempt to write
to the device -- the write will never complete (write() returns 0, or
blocks).
Signed-off-by: Randall Nortman <oss@wonderclown.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
        dbg("%s - port %d", __FUNCTION__, port->number);
 
        if (serial->num_bulk_out) {
-               if (port->write_urb_busy)
+               if (!(port->write_urb_busy))
                        room = port->bulk_out_size;
        }