diff options
| author | Johan Hovold <jhovold@gmail.com> | 2013-03-19 09:21:06 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-03-21 15:59:01 -0700 |
| commit | cb25505fc604292c70fc02143fc102f54c8595f0 (patch) | |
| tree | bc648be558cdcae4376ab51ca038653ad506b3c9 | |
| parent | c93d81955005c2ac0ea072f88d376026208410e1 (diff) | |
USB: cdc-acm: fix device unregistration
Unregister tty device in disconnect as is required by the USB stack.
By deferring unregistration to when the last tty reference is dropped,
the parent interface device can get unregistered before the child
resulting in broken hotplug events being generated when the tty is
finally closed:
KERNEL[2290.798128] remove /devices/pci0000:00/0000:00:1d.7/usb2/2-1/2-1:3.1 (usb)
KERNEL[2290.804589] remove /devices/pci0000:00/0000:00:1d.7/usb2/2-1 (usb)
KERNEL[2294.554799] remove /2-1:3.1/tty/ttyACM0 (tty)
The driver must deal with tty callbacks after disconnect by checking the
disconnected flag. Specifically, further opens must be prevented and
this is already implemented.
Cc: stable <stable@vger.kernel.org>
Cc: Oliver Neukum <oneukum@suse.de>
Acked-by: Oliver Neukum <oneukum@suse.de>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/usb/class/cdc-acm.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index c125b61c249..387dc6c8ad2 100644 --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -593,7 +593,6 @@ static void acm_port_destruct(struct tty_port *port) dev_dbg(&acm->control->dev, "%s\n", __func__); - tty_unregister_device(acm_tty_driver, acm->minor); acm_release_minor(acm); usb_put_intf(acm->control); kfree(acm->country_codes); @@ -1426,6 +1425,8 @@ static void acm_disconnect(struct usb_interface *intf) stop_data_traffic(acm); + tty_unregister_device(acm_tty_driver, acm->minor); + usb_free_urb(acm->ctrlurb); for (i = 0; i < ACM_NW; i++) usb_free_urb(acm->wb[i].urb); |