media: stkwebcam: fix runtime PM after driver unbind

commit 30045f2174aab7fb4db7a9cf902d0aa6c75856a7 upstream.

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.

Note that runtime PM has never actually been enabled for this driver
since the support_autosuspend flag in its usb_driver struct is not set.

Fixes: c2b71462d294 ("USB: core: Fix bug caused by duplicate interface PM usage counter")
Cc: stable <stable@vger.kernel.org>
Acked-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>
Link: https://lore.kernel.org/r/20191001084908.2003-5-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/media/usb/stkwebcam/stk-webcam.c b/drivers/media/usb/stkwebcam/stk-webcam.c
index 1c48f2f1e14aa55ada2e381d10025777a7882f81..7297fd261df947044cb443b8ab626c4ed8c2f774 100644 (file)
--- a/drivers/media/usb/stkwebcam/stk-webcam.c
+++ b/drivers/media/usb/stkwebcam/stk-webcam.c
@@ -647,8 +647,7 @@ static int v4l_stk_release(struct file *fp)
                dev->owner = NULL;
        }
 
-       if (is_present(dev))
-               usb_autopm_put_interface(dev->interface);
+       usb_autopm_put_interface(dev->interface);
        mutex_unlock(&dev->lock);
        return v4l2_fh_release(fp);
 }