[PATCH 4.4 67/91] usb: gadget: udc: fsl: Add missing complete function.

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Magnus Lilja <lilja.mag...@gmail.com>

commit 5528954a1a0c49c6974ef1b8d6eaceff536204d5 upstream.

Commit 304f7e5e1d08 ("usb: gadget: Refactor request completion")
removed check if req->req.complete is non-NULL, resulting in a NULL
pointer derefence and a kernel panic.
This patch adds an empty complete function instead of re-introducing
the req->req.complete check.

Fixes: 304f7e5e1d08 ("usb: gadget: Refactor request completion")

Signed-off-by: Magnus Lilja <lilja.mag...@gmail.com>
Signed-off-by: Felipe Balbi <felipe.ba...@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 drivers/usb/gadget/udc/fsl_udc_core.c |   10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

--- a/drivers/usb/gadget/udc/fsl_udc_core.c
+++ b/drivers/usb/gadget/udc/fsl_udc_core.c
@@ -1249,6 +1249,12 @@ static const struct usb_gadget_ops fsl_g
        .udc_stop = fsl_udc_stop,
 };
 
+/*
+ * Empty complete function used by this driver to fill in the req->complete
+ * field when creating a request since the complete field is mandatory.
+ */
+static void fsl_noop_complete(struct usb_ep *ep, struct usb_request *req) { }
+
 /* Set protocol stall on ep0, protocol stall will automatically be cleared
    on new transaction */
 static void ep0stall(struct fsl_udc *udc)
@@ -1283,7 +1289,7 @@ static int ep0_prime_status(struct fsl_u
        req->req.length = 0;
        req->req.status = -EINPROGRESS;
        req->req.actual = 0;
-       req->req.complete = NULL;
+       req->req.complete = fsl_noop_complete;
        req->dtd_count = 0;
 
        ret = usb_gadget_map_request(&ep->udc->gadget, &req->req, ep_is_in(ep));
@@ -1366,7 +1372,7 @@ static void ch9getstatus(struct fsl_udc
        req->req.length = 2;
        req->req.status = -EINPROGRESS;
        req->req.actual = 0;
-       req->req.complete = NULL;
+       req->req.complete = fsl_noop_complete;
        req->dtd_count = 0;
 
        ret = usb_gadget_map_request(&ep->udc->gadget, &req->req, ep_is_in(ep));