usb: phy: am335x: fix race condition in _probe

BugLink: https://bugs.launchpad.net/bugs/1818813

commit a53469a6 upstream.

power off the phy should be done before populate the phy. Otherwise,
am335x_init() could be called by the phy owner to power on the phy first,
then am335x_phy_probe() turns off the phy again without the caller knowing
it.

Fixes: 2fc711d7 ("usb: phy: am335x: Enable USB remote wakeup using PHY wakeup")
Cc: stable@vger.kernel.org # v3.18+
Signed-off-by: Bin Liu <b-liu@ti.com>
Signed-off-by: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Juerg Haefliger <juergh@canonical.com>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>

drivers/usb/phy/phy-am335x.c

@@ -56,9 +56,6 @@ static int am335x_phy_probe(struct platform_device *pdev)
 	if (ret)
 		return ret;
 
-	ret = usb_add_phy_dev(&am_phy->usb_phy_gen.phy);
-	if (ret)
-		return ret;
 	am_phy->usb_phy_gen.phy.init = am335x_init;
 	am_phy->usb_phy_gen.phy.shutdown = am335x_shutdown;
 
@@ -77,7 +74,7 @@ static int am335x_phy_probe(struct platform_device *pdev)
 	device_set_wakeup_enable(dev, false);
 	phy_ctrl_power(am_phy->phy_ctrl, am_phy->id, false);
 
-	return 0;
+	return usb_add_phy_dev(&am_phy->usb_phy_gen.phy);
 }
 
 static int am335x_phy_remove(struct platform_device *pdev)