usb: add devicetree helpers for determining dr_mode and phy_type

This adds two little devicetree helper functions for determining the
dr_mode (host, peripheral, otg) and phy_type (utmi, ulpi,...) from
the devicetree.

Signed-off-by: Michael Grzeschik <m.grzeschik@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 47 insertions, 0 deletions

diff --git a/drivers/usb/phy/of.c b/drivers/usb/phy/of.c
new file mode 100644
index 000000000000..7ea0154da9d5
--- /dev/null
+++ b/drivers/usb/phy/of.c
@@ -0,0 +1,47 @@
+/*
+ * USB of helper code
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/usb/of.h>
+#include <linux/usb/otg.h>
+
+static const char *const usbphy_modes[] = {
+        [USBPHY_INTERFACE_MODE_UNKNOWN] = "",
+        [USBPHY_INTERFACE_MODE_UTMI]    = "utmi",
+        [USBPHY_INTERFACE_MODE_UTMIW]   = "utmi_wide",
+        [USBPHY_INTERFACE_MODE_ULPI]    = "ulpi",
+        [USBPHY_INTERFACE_MODE_SERIAL]  = "serial",
+        [USBPHY_INTERFACE_MODE_HSIC]    = "hsic",
+};
+
+/**
+ * of_usb_get_phy_mode - Get phy mode for given device_node
+ * @np: Pointer to the given device_node
+ *
+ * The function gets phy interface string from property 'phy_type',
+ * and returns the correspondig enum usb_phy_interface
+ */
+enum usb_phy_interface of_usb_get_phy_mode(struct device_node *np)
+{
+        const char *phy_type;
+        int err, i;
+
+        err = of_property_read_string(np, "phy_type", &phy_type);
+        if (err < 0)
+                return USBPHY_INTERFACE_MODE_UNKNOWN;
+
+        for (i = 0; i < ARRAY_SIZE(usbphy_modes); i++)
+                if (!strcmp(phy_type, usbphy_modes[i]))
+                        return i;
+
+        return USBPHY_INTERFACE_MODE_UNKNOWN;
+}
+EXPORT_SYMBOL_GPL(of_usb_get_phy_mode);