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@@ -0,0 +1,65 @@
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+/*
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+ * otg.c -- USB OTG utility code
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+ *
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+ * Copyright (C) 2004 Texas Instruments
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+ *
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+ * This program is free software; you can redistribute it and/or modify
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+ * it under the terms of the GNU General Public License as published by
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+ * the Free Software Foundation; either version 2 of the License, or
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+ * (at your option) any later version.
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+ */
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+
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+#include <linux/kernel.h>
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+#include <linux/device.h>
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+
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+#include <linux/usb/otg.h>
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+
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+static struct otg_transceiver *xceiv;
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+
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+/**
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+ * otg_get_transceiver - find the (single) OTG transceiver
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+ *
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+ * Returns the transceiver driver, after getting a refcount to it; or
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+ * null if there is no such transceiver. The caller is responsible for
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+ * calling otg_put_transceiver() to release that count.
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+ *
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+ * For use by USB host and peripheral drivers.
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+ */
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+struct otg_transceiver *otg_get_transceiver(void)
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+{
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+ if (xceiv)
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+ get_device(xceiv->dev);
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+ return xceiv;
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+}
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+EXPORT_SYMBOL(otg_get_transceiver);
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+
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+/**
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+ * otg_put_transceiver - release the (single) OTG transceiver
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+ * @x: the transceiver returned by otg_get_transceiver()
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+ *
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+ * Releases a refcount the caller received from otg_get_transceiver().
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+ *
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+ * For use by USB host and peripheral drivers.
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+ */
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+void otg_put_transceiver(struct otg_transceiver *x)
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+{
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+ put_device(x->dev);
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+}
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+EXPORT_SYMBOL(otg_put_transceiver);
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+
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+/**
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+ * otg_set_transceiver - declare the (single) OTG transceiver
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+ * @x: the USB OTG transceiver to be used; or NULL
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+ *
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+ * This call is exclusively for use by transceiver drivers, which
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+ * coordinate the activities of drivers for host and peripheral
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+ * controllers, and in some cases for VBUS current regulation.
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+ */
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+int otg_set_transceiver(struct otg_transceiver *x)
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+{
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+ if (xceiv && x)
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+ return -EBUSY;
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+ xceiv = x;
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+ return 0;
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+}
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+EXPORT_SYMBOL(otg_set_transceiver);
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