source: mainline/uspace/lib/usb/src/pipes.c@ dc04868

/*
 * Copyright (c) 2011 Vojtech Horky
 * 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
 * USB endpoint pipes miscellaneous functions.
 */
#include <usb/usb.h>
#include <usb/pipes.h>
#include <errno.h>
#include <assert.h>
#include <usb/usbdrv.h>

/** Initialize connection to USB device.
 *
 * @param connection Connection structure to be initialized.
 * @param device Generic device backing the USB device.
 * @return Error code.
 */
int usb_device_connection_initialize_from_device(
    usb_device_connection_t *connection, device_t *device)
{
        assert(connection);
        assert(device);

        int rc;
        devman_handle_t hc_handle;
        usb_address_t my_address;

        rc = usb_drv_find_hc(device, &hc_handle);
        if (rc != EOK) {
                return rc;
        }

        int hc_phone = devman_device_connect(hc_handle, 0);
        if (hc_phone < 0) {
                return hc_phone;
        }

        my_address = usb_drv_get_my_address(hc_phone, device);
        if (my_address < 0) {
                rc = my_address;
                goto leave;
        }

        rc = usb_device_connection_initialize(connection,
            hc_handle, my_address);

leave:
        async_hangup(hc_phone);
        return rc;
}

/** Initialize connection to USB device.
 *
 * @param connection Connection structure to be initialized.
 * @param host_controller_handle Devman handle of host controller device is
 *      connected to.
 * @param device_address Device USB address.
 * @return Error code.
 */
int usb_device_connection_initialize(usb_device_connection_t *connection,
    devman_handle_t host_controller_handle, usb_address_t device_address)
{
        assert(connection);

        if ((device_address < 0) || (device_address >= USB11_ADDRESS_MAX)) {
                return EINVAL;
        }

        connection->hc_handle = host_controller_handle;
        connection->address = device_address;

        return EOK;
}


/** Start a session on the endpoint pipe.
 *
 * A session is something inside what any communication occurs.
 * It is expected that sessions would be started right before the transfer
 * and ended - see usb_endpoint_pipe_end_session() - after the last
 * transfer.
 * The reason for this is that session actually opens some communication
 * channel to the host controller (or to the physical hardware if you
 * wish) and thus it involves acquiring kernel resources.
 * Since they are limited, sessions shall not be longer than strictly
 * necessary.
 *
 * @param pipe Endpoint pipe to start the session on.
 * @return Error code.
 */
int usb_endpoint_pipe_start_session(usb_endpoint_pipe_t *pipe)
{
        assert(pipe);

        if (pipe->hc_phone >= 0) {
                return EBUSY;
        }

        int phone = devman_device_connect(pipe->wire->hc_handle, 0);
        if (phone < 0) {
                return phone;
        }

        pipe->hc_phone = phone;

        return EOK;
}


/** Ends a session on the endpoint pipe.
 *
 * @see usb_endpoint_pipe_start_session
 *
 * @param pipe Endpoint pipe to end the session on.
 * @return Error code.
 */
int usb_endpoint_pipe_end_session(usb_endpoint_pipe_t *pipe)
{
        assert(pipe);

        if (pipe->hc_phone < 0) {
                return ENOENT;
        }

        int rc = async_hangup(pipe->hc_phone);
        if (rc != EOK) {
                return rc;
        }

        pipe->hc_phone = -1;

        return EOK;
}

/**
 * @}
 */