source: mainline/uspace/lib/usb/src/hc.c@ f3922c2

/*
 * Copyright (c) 2011 Vojtech Horky
 * Copyright (c) 2011 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.
 */

/** @addtogroup libusb
 * @{
 */
/** @file
 * General communication with host controller driver (implementation).
 */

#include <usb/debug.h>

#include <assert.h>
#include <errno.h>
#include <usbhc_iface.h>
#include <usb/dev.h>
#include <usb/hc.h>

static int usb_hc_connection_add_ref(usb_hc_connection_t *connection)
{
        assert(connection);
        
        fibril_mutex_lock(&connection->guard);
        if (connection->ref_count == 0) {
                assert(connection->hc_sess == NULL);
                /* Parallel exchange for us */
                connection->hc_sess = devman_device_connect(EXCHANGE_PARALLEL,
                        connection->hc_handle, 0);
                if (!connection->hc_sess) {
                        fibril_mutex_unlock(&connection->guard);
                        return ENOMEM;
                }
        }
        
        ++connection->ref_count;
        fibril_mutex_unlock(&connection->guard);
        return EOK;
}

static int usb_hc_connection_del_ref(usb_hc_connection_t *connection)
{
        assert(connection);
        
        fibril_mutex_lock(&connection->guard);
        if (connection->ref_count == 0) {
                /* Closing already closed connection... */
                assert(connection->hc_sess == NULL);
                fibril_mutex_unlock(&connection->guard);
                return EOK;
        }
        
        --connection->ref_count;
        int ret = EOK;
        if (connection->ref_count == 0) {
                assert(connection->hc_sess);
                ret = async_hangup(connection->hc_sess);
                connection->hc_sess = NULL;
        }
        fibril_mutex_unlock(&connection->guard);
        return ret;
}

#define EXCH_INIT(connection, exch) \
do { \
        exch = NULL; \
        if (!connection) \
                return EBADMEM; \
        const int ret = usb_hc_connection_add_ref(connection); \
        if (ret != EOK) \
                return ret; \
        exch = async_exchange_begin(connection->hc_sess); \
        if (exch == NULL) { \
                usb_hc_connection_del_ref(connection); \
                return ENOMEM; \
        } \
} while (0)

#define EXCH_FINI(connection, exch) \
if (exch) { \
        async_exchange_end(exch); \
        usb_hc_connection_del_ref(connection); \
} else (void)0


void usb_hc_connection_deinitialize(usb_hc_connection_t *connection)
{
        assert(connection);
        fibril_mutex_lock(&connection->guard);
        if (connection->ref_count != 0) {
                usb_log_warning("%u stale reference(s) to HC connection.\n",
                    connection->ref_count);
                assert(connection->hc_sess);
                async_hangup(connection->hc_sess);
                connection->hc_sess = NULL;
                connection->ref_count = 0;
        }
        fibril_mutex_unlock(&connection->guard);
}

/** Open connection to host controller.
 *
 * @param connection Connection to the host controller.
 * @return Error code.
 */
int usb_hc_connection_open(usb_hc_connection_t *connection)
{
        return usb_hc_connection_add_ref(connection);
}

/** Close connection to the host controller.
 *
 * @param connection Connection to the host controller.
 * @return Error code.
 */
int usb_hc_connection_close(usb_hc_connection_t *connection)
{
        return usb_hc_connection_del_ref(connection);
}


/** Get handle of USB device with given address.
 *
 * @param[in] connection Opened connection to host controller.
 * @param[in] address Address of device in question.
 * @param[out] handle Where to write the device handle.
 * @return Error code.
 */
int usb_hc_get_handle_by_address(usb_hc_connection_t *connection,
    usb_address_t address, devman_handle_t *handle)
{
        async_exch_t *exch;
        EXCH_INIT(connection, exch);

        const int ret = usbhc_get_handle(exch, address, handle);

        EXCH_FINI(connection, exch);
        return ret;
}

int usb_hc_read(usb_hc_connection_t *connection, usb_address_t address,
    usb_endpoint_t endpoint, uint64_t setup, void *data, size_t size,
    size_t *real_size)
{
        async_exch_t *exch;
        EXCH_INIT(connection, exch);

        const int ret =
            usbhc_read(exch, address, endpoint, setup, data, size, real_size);

        EXCH_FINI(connection, exch);
        return ret;
}

int usb_hc_write(usb_hc_connection_t *connection, usb_address_t address,
    usb_endpoint_t endpoint, uint64_t setup, const void *data, size_t size)
{
        async_exch_t *exch;
        EXCH_INIT(connection, exch);

        const int ret = usbhc_write(exch, address, endpoint, setup, data, size);

        EXCH_FINI(connection, exch);
        return ret;
}

/**
 * @}
 */