dwc3: core: added an API to invoke irq handlers

Since interrupt support is not present in u-boot, added an
API to handle the interrupts in dwc3 core. This API can be
polled to handle the interrupts.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>
diff --git a/drivers/usb/dwc3/core.c b/drivers/usb/dwc3/core.c
index bd34dbd..5a8d5ea 100644
--- a/drivers/usb/dwc3/core.c
+++ b/drivers/usb/dwc3/core.c
@@ -758,6 +758,27 @@
 	}
 }
 
+/**
+ * dwc3_uboot_handle_interrupt - handle dwc3 core interrupt
+ * @index: index of this controller
+ *
+ * Invokes dwc3 gadget interrupts.
+ *
+ * Generally called from board file.
+ */
+void dwc3_uboot_handle_interrupt(int index)
+{
+	struct dwc3 *dwc = NULL;
+
+	list_for_each_entry(dwc, &dwc3_list, list) {
+		if (dwc->index != index)
+			continue;
+
+		dwc3_gadget_uboot_handle_interrupt(dwc);
+		break;
+	}
+}
+
 MODULE_ALIAS("platform:dwc3");
 MODULE_AUTHOR("Felipe Balbi <balbi@ti.com>");
 MODULE_LICENSE("GPL v2");