source: mainline/uspace/drv/bus/usb/usbmid/usbmid.c

/*
 * Copyright (c) 2011 Vojtech Horky
 * Copyright (c) 2018 Ondrej Hlavaty
 * 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 drvusbmid
 * @{
 */

/**
 * @file
 * Helper functions.
 */

#include <errno.h>
#include <str_error.h>
#include <stdlib.h>
#include <usb_iface.h>
#include <usb/dev/pipes.h>
#include <usb/classes/classes.h>
#include <usb/dev/recognise.h>
#include "usbmid.h"

/**
 * Get USB device description by calling HC and altering the interface field.
 *
 * @param[in] fun Device function the operation is running on.
 * @param[out] desc Device descriptor.
 * @return Error code.
 */
static errno_t usb_iface_description(ddf_fun_t *fun, usb_device_desc_t *desc)
{
        usbmid_interface_t *iface = ddf_fun_data_get(fun);
        assert(iface);
        usb_device_t *usb_dev = ddf_dev_data_get(ddf_fun_get_dev(fun));
        assert(usb_dev);

        async_exch_t *exch = usb_device_bus_exchange_begin(usb_dev);
        if (!exch)
                return EPARTY;

        usb_device_desc_t tmp_desc;
        const errno_t ret = usb_get_my_description(exch, &tmp_desc);

        if (ret == EOK && desc) {
                *desc = tmp_desc;
                desc->iface = iface->interface_no;
        }

        usb_device_bus_exchange_end(exch);

        return EOK;
}

/** DDF interface of the child - USB functions. */
static usb_iface_t child_usb_iface = {
        .get_my_description = usb_iface_description,
};

/** Operations for children - interface functions. */
static ddf_dev_ops_t child_device_ops = {
        .interfaces[USB_DEV_IFACE] = &child_usb_iface
};

errno_t usbmid_interface_destroy(usbmid_interface_t *mid_iface)
{
        assert(mid_iface);
        assert_link_not_used(&mid_iface->link);
        const errno_t ret = ddf_fun_unbind(mid_iface->fun);
        if (ret != EOK) {
                return ret;
        }
        ddf_fun_destroy(mid_iface->fun);
        return EOK;
}

/** Spawn new child device from one interface.
 *
 * @param parent Parent MID device.
 * @param iface Interface information.
 * @param device_descriptor Device descriptor.
 * @param interface_descriptor Interface descriptor.
 * @return Error code.
 */
errno_t usbmid_spawn_interface_child(usb_device_t *parent,
    usbmid_interface_t **iface_ret,
    const usb_standard_device_descriptor_t *device_descriptor,
    const usb_standard_interface_descriptor_t *interface_descriptor)
{
        ddf_fun_t *child = NULL;
        char *child_name = NULL;
        errno_t rc;

        /*
         * Name is class name followed by interface number.
         * The interface number shall provide uniqueness while the
         * class name something humanly understandable.
         */
        errno_t ret = asprintf(&child_name, "%s%hhu",
            usb_str_class(interface_descriptor->interface_class),
            interface_descriptor->interface_number);
        if (ret < 0) {
                return ENOMEM;
        }

        /* Create the device. */
        child = usb_device_ddf_fun_create(parent, fun_inner, child_name);
        free(child_name);
        if (child == NULL) {
                return ENOMEM;
        }

        match_id_list_t match_ids;
        init_match_ids(&match_ids);

        rc = usb_device_create_match_ids_from_interface(device_descriptor,
            interface_descriptor, &match_ids);
        if (rc != EOK) {
                ddf_fun_destroy(child);
                return rc;
        }

        list_foreach(match_ids.ids, link, match_id_t, match_id) {
                rc = ddf_fun_add_match_id(child, match_id->id, match_id->score);
                if (rc != EOK) {
                        clean_match_ids(&match_ids);
                        ddf_fun_destroy(child);
                        return rc;
                }
        }
        clean_match_ids(&match_ids);
        ddf_fun_set_ops(child, &child_device_ops);

        usbmid_interface_t *iface = ddf_fun_data_alloc(child, sizeof(*iface));

        iface->fun = child;
        iface->interface_no = interface_descriptor->interface_number;
        link_initialize(&iface->link);

        rc = ddf_fun_bind(child);
        if (rc != EOK) {
                /* This takes care of match_id deallocation as well. */
                ddf_fun_destroy(child);
                return rc;
        }
        *iface_ret = iface;

        return EOK;
}

/**
 * @}
 */