This patch (as1266) changes the way usb-serial manages its minor
numbers. There's no need to retain a minor number after the device
has been disconnected, since the only thing the minor gets used for is
to determine which port corresponds to a device file during open().
(It also gets used in serial_proc_show, but we don't have to worry
about that.)
Returning minor numbers during serial_disconnect rather than
destroy_serial allows the numbers (and hence device node names) to be
reused even when a process is holding an unplugged device's file open.
This is what users expect to happen, and there's no reason not to do
it.
Signed-off-by: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>
---
Not intended for 2.6.31, although it could be merged immediately if
there are no objections.
Index: usb-2.6/drivers/usb/serial/usb-serial.c
===================================================================
--- usb-2.6.orig/drivers/usb/serial/usb-serial.c
+++ usb-2.6/drivers/usb/serial/usb-serial.c
@@ -138,10 +138,6 @@ static void destroy_serial(struct kref *
dbg("%s - %s", __func__, serial->type->description);
- /* return the minor range that this device had */
- if (serial->minor != SERIAL_TTY_NO_MINOR)
- return_serial(serial);
-
serial->type->release(serial);
for (i = 0; i < serial->num_ports; ++i) {
@@ -1157,6 +1153,10 @@ void usb_serial_disconnect(struct usb_in
}
serial->type->disconnect(serial);
+ /* return the minor range that this device had */
+ if (serial->minor != SERIAL_TTY_NO_MINOR)
+ return_serial(serial);
+
/* let the last holder of this object
* cause it to be cleaned up */
usb_serial_put(serial);
--
To unsubscribe from this list: send the line "unsubscribe linux-usb" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
