usb: usbtmc: Fix disconnect/poll interaction

When the device is disconnected poll waiters were not being woken.

Changes for v2:
  - add commit summary
  - add Fixes and Reported-by tags

Fixes: eb6b92ecc0f9 ("Add support for receiving USBTMC USB488 SRQ notifications via poll/select")
Reported-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Dave Penkler <dpenkler@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/usb/class/usbtmc.c b/drivers/usb/class/usbtmc.c
index 419c72e10464..917a55c4480d 100644
--- a/drivers/usb/class/usbtmc.c
+++ b/drivers/usb/class/usbtmc.c
@@ -1525,13 +1525,14 @@ static void usbtmc_disconnect(struct usb_interface *intf)
         dev_dbg(&intf->dev, "usbtmc_disconnect called\n");
 
         data = usb_get_intfdata(intf);
-        usbtmc_free_int(data);
         usb_deregister_dev(intf, &usbtmc_class);
         sysfs_remove_group(&intf->dev.kobj, &capability_attr_grp);
         sysfs_remove_group(&intf->dev.kobj, &data_attr_grp);
         mutex_lock(&data->io_mutex);
         data->zombie = 1;
+        wake_up_all(&data->waitq);
         mutex_unlock(&data->io_mutex);
+        usbtmc_free_int(data);
         kref_put(&data->kref, usbtmc_delete);
 }