queue_head.h

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/*
 * Copyright (c) 2010 Jan Vesely
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
#ifndef DRV_UHCI_HW_STRUCT_QH_H
#define DRV_UHCI_HW_STRUCT_QH_H
#include <assert.h>

#include "link_pointer.h"
#include "transfer_descriptor.h"
#include "../utils/malloc32.h"

typedef struct queue_head {
        volatile link_pointer_t next;
        volatile link_pointer_t element;
} __attribute__((packed)) qh_t;
/*----------------------------------------------------------------------------*/
static inline void qh_init(qh_t *instance)
{
        assert(instance);

        instance->element = 0 | LINK_POINTER_TERMINATE_FLAG;
        instance->next = 0 | LINK_POINTER_TERMINATE_FLAG;
}
/*----------------------------------------------------------------------------*/
static inline void qh_set_next_qh(qh_t *instance, qh_t *next)
{
        uint32_t pa = addr_to_phys(next);
        if (pa) {
                instance->next = LINK_POINTER_QH(pa);
        } else {
                instance->next = LINK_POINTER_TERM;
        }
}
/*----------------------------------------------------------------------------*/
static inline void qh_set_element_td(qh_t *instance, td_t *td)
{
        uint32_t pa = addr_to_phys(td);
        if (pa) {
                instance->element = LINK_POINTER_TD(pa);
        } else {
                instance->element = LINK_POINTER_TERM;
        }
}
#endif

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