usb: gadget: function: acm: make f_acm pass USB20CV Chapter9

During Halt Endpoint Test, our interrupt endpoint
will be disabled, which will clear out ep->desc
to NULL. Unless we call config_ep_by_speed() again,
we will not be able to enable this endpoint which
will make us fail that test.

Fixes: f9c56cd (usb: gadget: Clear usb_endpoint_descriptor
	inside the struct usb_ep on disable)
Cc: <stable@vger.kernel.org> # v3.4+
Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --git a/drivers/usb/gadget/function/f_acm.c b/drivers/usb/gadget/function/f_acm.c
index 6da4685490ef7668dfdbc8be950cfbd63dd2d3cb..aad8165e98ef84d314f74826e97d1bd0641a5b95 100644 (file)
--- a/drivers/usb/gadget/function/f_acm.c
+++ b/drivers/usb/gadget/function/f_acm.c
@@ -433,12 +433,12 @@ static int acm_set_alt(struct usb_function *f, unsigned intf, unsigned alt)
                        dev_vdbg(&cdev->gadget->dev,
                                 "reset acm control interface %d\n", intf);
                        usb_ep_disable(acm->notify);
-               } else {
-                       dev_vdbg(&cdev->gadget->dev,
-                                "init acm ctrl interface %d\n", intf);
+               }
+
+               if (!acm->notify->desc)
                        if (config_ep_by_speed(cdev->gadget, f, acm->notify))
                                return -EINVAL;
-               }
+
                usb_ep_enable(acm->notify);
                acm->notify->driver_data = acm;