drivers: usb: common: add common code for usb drivers to use

Add common usb code which usb drivers makes use of it.

Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Reviewed-by: Simon Glass <sjg@chromium.org>

drivers/usb/common/Makefile

@@ -3,5 +3,6 @@
 # SPDX-License-Identifier:      GPL-2.0+
 #
 
+obj-$(CONFIG_DM_USB) += common.o
 obj-$(CONFIG_USB_EHCI_FSL) += fsl-dt-fixup.o
 obj-$(CONFIG_USB_XHCI_FSL) += fsl-dt-fixup.o

drivers/usb/common/common.c

@@ -0,0 +1,40 @@
+/*
+ * Provides code common for host and device side USB.
+ *
+ * (C) Copyright 2016
+ *     Texas Instruments Incorporated, <www.ti.com>
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#include <common.h>
+#include <libfdt.h>
+#include <linux/usb/otg.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static const char *const usb_dr_modes[] = {
+	[USB_DR_MODE_UNKNOWN]		= "",
+	[USB_DR_MODE_HOST]		= "host",
+	[USB_DR_MODE_PERIPHERAL]	= "peripheral",
+	[USB_DR_MODE_OTG]		= "otg",
+};
+
+enum usb_dr_mode usb_get_dr_mode(int node)
+{
+	const void *fdt = gd->fdt_blob;
+	const char *dr_mode;
+	int i;
+
+	dr_mode = fdt_getprop(fdt, node, "dr_mode", NULL);
+	if (!dr_mode) {
+		error("usb dr_mode not found\n");
+		return USB_DR_MODE_UNKNOWN;
+	}
+
+	for (i = 0; i < ARRAY_SIZE(usb_dr_modes); i++)
+		if (!strcmp(dr_mode, usb_dr_modes[i]))
+			return i;
+
+	return USB_DR_MODE_UNKNOWN;
+}

include/linux/usb/otg.h

@@ -17,4 +17,13 @@ enum usb_dr_mode {
 	USB_DR_MODE_OTG,
 };
 
+/**
+ * usb_get_dr_mode() - Get dual role mode for given device
+ * @node: Node offset to the given device
+ *
+ * The function gets phy interface string from property 'dr_mode',
+ * and returns the correspondig enum usb_dr_mode
+ */
+enum usb_dr_mode usb_get_dr_mode(int node);
+
 #endif /* __LINUX_USB_OTG_H */