USB: unbind all interfaces before rebinding them

This patch (as1387) fixes a bug introduced during the changeover to
the runtime PM framework.  When a driver doesn't support resume or
reset-resume, and consequently its interfaces need to be unbound and
rebound, we have to unbind all the interfaces before trying to rebind
any of them.  Otherwise the driver's probe method for one interface
could try to claim a different interface and fail, because that other
interface hasn't been unbound yet.

This fixes Bugzilla #15788.  The symptom is that some USB sound cards
don't work after hibernation.

Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Tested-by: François Valenduc <francois.valenduc@tvcablenet.be>
Cc: stable <stable@kernel.org> [.34]
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 2 insertions, 0 deletions

diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index ded550eda5d9..de98a94d1853 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -1328,6 +1328,7 @@ int usb_resume(struct device *dev, pm_message_t msg)
 
         /* For all other calls, take the device back to full power and
          * tell the PM core in case it was autosuspended previously.
+         * Unbind the interfaces that will need rebinding later.
          */
         } else {
                 status = usb_resume_both(udev, msg);
@@ -1336,6 +1337,7 @@ int usb_resume(struct device *dev, pm_message_t msg)
                         pm_runtime_set_active(dev);
                         pm_runtime_enable(dev);
                         udev->last_busy = jiffies;
+                        do_unbind_rebind(udev, DO_REBIND);
                 }
         }