usb: dwc3: ep0: Don't reset resource alloc flag (including ep0)

The DWC3_EP_RESOURCE_ALLOCATED flag ensures that the resource of an
endpoint is only assigned once. Unless the endpoint is reset, don't
clear this flag. Otherwise we may set endpoint resource again, which
prevents the driver from initiate transfer after handling a STALL or
endpoint halt to the control endpoint.

Commit f2e0eee ("usb: dwc3: ep0: Don't reset resource alloc flag")
was fixing the initial issue, but did this only for physical ep1. Since
the function dwc3_ep0_stall_and_restart is resetting the flags for both
physical endpoints, this also has to be done for ep0.

Cc: [email protected]
Fixes: b311048 ("usb: dwc3: gadget: Rewrite endpoint allocation flow")
Acked-by: Thinh Nguyen <[email protected]>
Signed-off-by: Michael Grzeschik <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Greg Kroah-Hartman <[email protected]>

Author: mgrzeschik

drivers/usb/dwc3/ep0.c

@@ -232,7 +232,8 @@ void dwc3_ep0_stall_and_restart(struct dwc3 *dwc)
 	/* stall is always issued on EP0 */
 	dep = dwc->eps[0];
 	__dwc3_gadget_ep_set_halt(dep, 1, false);
-	dep->flags = DWC3_EP_ENABLED;
+	dep->flags &= DWC3_EP_RESOURCE_ALLOCATED;
+	dep->flags |= DWC3_EP_ENABLED;
 	dwc->delayed_status = false;
 
 	if (!list_empty(&dep->pending_list)) {