USB: usblp: fix runtime PM after driver unbind

Since commit c2b71462d294 ("USB: core: Fix bug caused by duplicate
interface PM usage counter") USB drivers must always balance their
runtime PM gets and puts, including when the driver has already been
unbound from the interface.

Leaving the interface with a positive PM usage counter would prevent a
later bound driver from suspending the device.

Fixes: c2b71462d294 ("USB: core: Fix bug caused by duplicate interface PM usage counter")
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191001084908.2003-3-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/class/usblp.c b/drivers/usb/class/usblp.c
index 7fea4999d352956bd4221ef9a827dd58113535ee..fb8bd60c83f487d67c1b1479dc2d1cf86d1a8bed 100644 (file)
--- a/drivers/usb/class/usblp.c
+++ b/drivers/usb/class/usblp.c
@@ -461,10 +461,12 @@ static int usblp_release(struct inode *inode, struct file *file)
 
        mutex_lock(&usblp_mutex);
        usblp->used = 0;
-       if (usblp->present) {
+       if (usblp->present)
                usblp_unlink_urbs(usblp);
-               usb_autopm_put_interface(usblp->intf);
-       } else          /* finish cleanup from disconnect */
+
+       usb_autopm_put_interface(usblp->intf);
+
+       if (!usblp->present)            /* finish cleanup from disconnect */
                usblp_cleanup(usblp);
        mutex_unlock(&usblp_mutex);
        return 0;