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

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

From: Kazuya Mizuguchi <redacted>

commit 11432050f070810ba139d0226344eef120c3a559 upstream.

This patch fixes an issue that the NULL pointer dereference happens
when we uses g_audio driver. Since the g_audio driver will call
usb_ep_disable() in afunc_set_alt() before it calls usb_ep_enable(),
the uep->pipe of renesas usbhs driver will be NULL. So, this patch
adds a condition to avoid the oops.

Signed-off-by: Kazuya Mizuguchi <redacted>
Signed-off-by: Takeshi Kihara <redacted>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Fixes: 2f98382dc (usb: renesas_usbhs: Add Renesas USBHS Gadget)
Signed-off-by: Felipe Balbi <redacted>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/usb/renesas_usbhs/mod_gadget.c |    3 +++
 1 file changed, 3 insertions(+)

--- a/drivers/usb/renesas_usbhs/mod_gadget.c
+++ b/drivers/usb/renesas_usbhs/mod_gadget.c

@@ -602,6 +602,9 @@ static int usbhsg_ep_disable(struct usb_
 	struct usbhsg_uep *uep = usbhsg_ep_to_uep(ep);
 	struct usbhs_pipe *pipe = usbhsg_uep_to_pipe(uep);
 
+	if (!pipe)
+		return -EINVAL;
+
 	usbhsg_pipe_disable(uep);
 	usbhs_pipe_free(pipe);