USB: musb: do not work if no gadget driver is loaded

On OTG and gadget-only configurations, we need a gadget driver
in order to work properly, so avoid changing operation modes
when there's no gadget driver loaded.

Signed-off-by: Felipe Balbi <felipe.balbi@nokia.com>
Cc: David Brownell <dbrownell@users.sourceforge.net>
Acked-by: Anand Gadiyar <gadiyar@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/usb/musb/musb_core.c b/drivers/usb/musb/musb_core.c
index 1041bb734bb4..24ff09754e0c 100644
--- a/drivers/usb/musb/musb_core.c
+++ b/drivers/usb/musb/musb_core.c
@@ -1521,6 +1521,14 @@ irqreturn_t musb_interrupt(struct musb *musb)
                 (devctl & MUSB_DEVCTL_HM) ? "host" : "peripheral",
                 musb->int_usb, musb->int_tx, musb->int_rx);
 
+#ifdef CONFIG_USB_GADGET_MUSB_HDRC
+        if (is_otg_enabled(musb) || is_peripheral_enabled(musb))
+                if (!musb->gadget_driver) {
+                        DBG(5, "No gadget driver loaded\n");
+                        return IRQ_HANDLED;
+                }
+#endif
+
         /* the core can interrupt us for multiple reasons; docs have
          * a generic interrupt flowchart to follow
          */