source: mainline/uspace/lib/usbhost/src/usb_endpoint_manager.c@ d8cdf39e

/*
 * Copyright (c) 2011 Jan Vesely
 * All rights eps.
 *
 * 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 libusbhost
 * @{
 */
/** @file
 * HC Endpoint management.
 */

#include <stdbool.h>
#include <assert.h>
#include <errno.h>

#include <usb/debug.h>
#include <usb/host/usb_endpoint_manager.h>

/** Endpoint compare helper function.
 *
 * USB_DIRECTION_BOTH matches both IN and OUT.
 * @param ep Endpoint to compare, non-null.
 * @param address Tested address.
 * @param endpoint Tested endpoint number.
 * @param direction Tested direction.
 * @return True if ep can be used to communicate with given device,
 * false otherwise.
 */
static inline bool ep_match(const endpoint_t *ep,
    usb_address_t address, usb_endpoint_t endpoint, usb_direction_t direction)
{
        assert(ep);
        return
            ((direction == ep->direction)
                || (ep->direction == USB_DIRECTION_BOTH)
                || (direction == USB_DIRECTION_BOTH))
            && (endpoint == ep->endpoint)
            && (address == ep->address);
}

/** Get list that holds endpoints for given address.
 * @param instance usb_endpoint_manager structure, non-null.
 * @param addr USB address, must be >= 0.
 * @return Pointer to the appropriate list.
 */
static list_t * get_list(usb_endpoint_manager_t *instance, usb_address_t addr)
{
        assert(instance);
        assert(addr >= 0);
        return &instance->endpoint_lists[addr % ENDPOINT_LIST_COUNT];
}

/** Internal search function, works on locked structure.
 * @param instance usb_endpoint_manager structure, non-null.
 * @param address USB address, must be valid.
 * @param endpoint USB endpoint number.
 * @param direction Communication direction.
 * @return Pointer to endpoint_t structure representing given communication
 * target, NULL if there is no such endpoint registered.
 * @note Assumes that the internal mutex is locked.
 */
static endpoint_t * find_locked(usb_endpoint_manager_t *instance,
    usb_address_t address, usb_endpoint_t endpoint, usb_direction_t direction)
{
        assert(instance);
        assert(fibril_mutex_is_locked(&instance->guard));
        if (address < 0)
                return NULL;
        list_foreach(*get_list(instance, address), iterator) {
                endpoint_t *ep = endpoint_get_instance(iterator);
                if (ep_match(ep, address, endpoint, direction))
                        return ep;
        }
        return NULL;
}

/** Calculate bandwidth that needs to be reserved for communication with EP.
 * Calculation follows USB 1.1 specification.
 * @param speed Device's speed.
 * @param type Type of the transfer.
 * @param size Number of byte to transfer.
 * @param max_packet_size Maximum bytes in one packet.
 */
size_t bandwidth_count_usb11(usb_speed_t speed, usb_transfer_type_t type,
    size_t size, size_t max_packet_size)
{
        /* We care about bandwidth only for interrupt and isochronous. */
        if ((type != USB_TRANSFER_INTERRUPT)
            && (type != USB_TRANSFER_ISOCHRONOUS)) {
                return 0;
        }

        const unsigned packet_count =
            (size + max_packet_size - 1) / max_packet_size;
        /* TODO: It may be that ISO and INT transfers use only one packet per
         * transaction, but I did not find text in USB spec to confirm this */
        /* NOTE: All data packets will be considered to be max_packet_size */
        switch (speed)
        {
        case USB_SPEED_LOW:
                assert(type == USB_TRANSFER_INTERRUPT);
                /* Protocol overhead 13B
                 * (3 SYNC bytes, 3 PID bytes, 2 Endpoint + CRC bytes, 2
                 * CRC bytes, and a 3-byte interpacket delay)
                 * see USB spec page 45-46. */
                /* Speed penalty 8: low speed is 8-times slower*/
                return packet_count * (13 + max_packet_size) * 8;
        case USB_SPEED_FULL:
                /* Interrupt transfer overhead see above
                 * or page 45 of USB spec */
                if (type == USB_TRANSFER_INTERRUPT)
                        return packet_count * (13 + max_packet_size);

                assert(type == USB_TRANSFER_ISOCHRONOUS);
                /* Protocol overhead 9B
                 * (2 SYNC bytes, 2 PID bytes, 2 Endpoint + CRC bytes, 2 CRC
                 * bytes, and a 1-byte interpacket delay)
                 * see USB spec page 42 */
                return packet_count * (9 + max_packet_size);
        default:
                return 0;
        }
}

/** Initialize to default state.
 * You need to provide valid bw_count function if you plan to use
 * add_endpoint/remove_endpoint pair.
 *
 * @param instance usb_endpoint_manager structure, non-null.
 * @param available_bandwidth Size of the bandwidth pool.
 * @param bw_count function to use to calculate endpoint bw requirements.
 * @return Error code.
 */
int usb_endpoint_manager_init(usb_endpoint_manager_t *instance,
    size_t available_bandwidth, bw_count_func_t bw_count)
{
        assert(instance);
        fibril_mutex_initialize(&instance->guard);
        instance->free_bw = available_bandwidth;
        instance->bw_count = bw_count;
        for (unsigned i = 0; i < ENDPOINT_LIST_COUNT; ++i) {
                list_initialize(&instance->endpoint_lists[i]);
        }
        return EOK;
}

/** Register endpoint structure.
 * Checks for duplicates.
 * @param instance usb_endpoint_manager, non-null.
 * @param ep endpoint_t to register.
 * @param data_size Size of data to transfer.
 * @return Error code.
 */
int usb_endpoint_manager_register_ep(usb_endpoint_manager_t *instance,
    endpoint_t *ep, size_t data_size)
{
        assert(instance);
        if (ep == NULL || ep->address < 0)
                return EINVAL;

        fibril_mutex_lock(&instance->guard);
        /* Check for available bandwidth */
        if (ep->bandwidth > instance->free_bw) {
                fibril_mutex_unlock(&instance->guard);
                return ENOSPC;
        }

        /* Check for existence */
        const endpoint_t *endpoint =
            find_locked(instance, ep->address, ep->endpoint, ep->direction);
        if (endpoint != NULL) {
                fibril_mutex_unlock(&instance->guard);
                return EEXISTS;
        }
        list_append(&ep->link, get_list(instance, ep->address));

        instance->free_bw -= ep->bandwidth;
        fibril_mutex_unlock(&instance->guard);
        return EOK;
}

/** Unregister endpoint structure.
 * Checks for duplicates.
 * @param instance usb_endpoint_manager, non-null.
 * @param ep endpoint_t to unregister.
 * @return Error code.
 */
int usb_endpoint_manager_unregister_ep(
    usb_endpoint_manager_t *instance, endpoint_t *ep)
{
        assert(instance);
        if (ep == NULL || ep->address < 0)
                return EINVAL;

        fibril_mutex_lock(&instance->guard);
        if (!list_member(&ep->link, get_list(instance, ep->address))) {
                fibril_mutex_unlock(&instance->guard);
                return ENOENT;
        }
        list_remove(&ep->link);
        instance->free_bw += ep->bandwidth;
        fibril_mutex_unlock(&instance->guard);
        return EOK;
}

/** Find endpoint_t representing the given communication route.
 * @param instance usb_endpoint_manager, non-null.
 * @param address
 */
endpoint_t * usb_endpoint_manager_find_ep(usb_endpoint_manager_t *instance,
    usb_address_t address, usb_endpoint_t endpoint, usb_direction_t direction)
{
        assert(instance);

        fibril_mutex_lock(&instance->guard);
        endpoint_t *ep = find_locked(instance, address, endpoint, direction);
        fibril_mutex_unlock(&instance->guard);
        return ep;
}

/** Create and register new endpoint_t structure.
 * @param instance usb_endpoint_manager structure, non-null.
 * @param address USB address.
 * @param endpoint USB endpoint number.
 * @param direction Communication direction.
 * @param type USB transfer type.
 * @param speed USB Communication speed.
 * @param max_packet_size Maximum size of data packets.
 * @param data_size Expected communication size.
 * @param callback function to call just after registering.
 * @param arg Argument to pass to the callback function.
 * @return Error code.
 */
int usb_endpoint_manager_add_ep(usb_endpoint_manager_t *instance,
    usb_address_t address, usb_endpoint_t endpoint, usb_direction_t direction,
    usb_transfer_type_t type, usb_speed_t speed, size_t max_packet_size,
    size_t data_size, ep_add_callback_t callback, void *arg)
{
        assert(instance);
        if (instance->bw_count == NULL)
                return ENOTSUP;
        if (address < 0)
                return EINVAL;

        const size_t bw =
            instance->bw_count(speed, type, data_size, max_packet_size);

        fibril_mutex_lock(&instance->guard);
        /* Check for available bandwidth */
        if (bw > instance->free_bw) {
                fibril_mutex_unlock(&instance->guard);
                return ENOSPC;
        }

        /* Check for existence */
        endpoint_t *ep = find_locked(instance, address, endpoint, direction);
        if (ep != NULL) {
                fibril_mutex_unlock(&instance->guard);
                return EEXISTS;
        }

        ep = endpoint_create(
            address, endpoint, direction, type, speed, max_packet_size, bw);
        if (!ep) {
                fibril_mutex_unlock(&instance->guard);
                return ENOMEM;
        }

        if (callback) {
                const int ret = callback(ep, arg);
                if (ret != EOK) {
                        fibril_mutex_unlock(&instance->guard);
                        endpoint_destroy(ep);
                        return ret;
                }
        }
        list_append(&ep->link, get_list(instance, ep->address));

        instance->free_bw -= ep->bandwidth;
        fibril_mutex_unlock(&instance->guard);
        return EOK;
}

/** Unregister and destroy endpoint_t structure representing given route.
 * @param instance usb_endpoint_manager structure, non-null.
 * @param address USB address.
 * @param endpoint USB endpoint number.
 * @param direction Communication direction.
 * @param callback Function to call after unregister, before destruction.
 * @arg Argument to pass to the callback function.
 * @return Error code.
 */
int usb_endpoint_manager_remove_ep(usb_endpoint_manager_t *instance,
    usb_address_t address, usb_endpoint_t endpoint, usb_direction_t direction,
    void (*callback)(endpoint_t *, void *), void *arg)
{
        assert(instance);
        fibril_mutex_lock(&instance->guard);
        endpoint_t *ep = find_locked(instance, address, endpoint, direction);
        if (ep != NULL) {
                list_remove(&ep->link);
                instance->free_bw += ep->bandwidth;
        }
        fibril_mutex_unlock(&instance->guard);
        if (ep == NULL)
                return ENOENT;

        if (callback) {
                callback(ep, arg);
        }
        endpoint_destroy(ep);
        return EOK;
}

int usb_endpoint_manager_reset_toggle(usb_endpoint_manager_t *instance,
    usb_target_t target, bool all)
{
        assert(instance);
        if (!usb_target_is_valid(target)) {
                return EINVAL;
        }

        int rc = ENOENT;

        fibril_mutex_lock(&instance->guard);
        list_foreach(*get_list(instance, target.address), it) {
                endpoint_t *ep = endpoint_get_instance(it);
                if ((ep->address == target.address)
                    && (all || ep->endpoint == target.endpoint)) {
                        endpoint_toggle_set(ep, 0);
                        rc = EOK;
                }
        }
        fibril_mutex_unlock(&instance->guard);
        return rc;
}

/** Unregister and destroy all endpoints using given address.
 * @param instance usb_endpoint_manager structure, non-null.
 * @param address USB address.
 * @param endpoint USB endpoint number.
 * @param direction Communication direction.
 * @param callback Function to call after unregister, before destruction.
 * @arg Argument to pass to the callback function.
 * @return Error code.
 */
void usb_endpoint_manager_remove_address(usb_endpoint_manager_t *instance,
    usb_address_t address, void (*callback)(endpoint_t *, void *), void *arg)
{
        assert(address >= 0);
        assert(instance);
        fibril_mutex_lock(&instance->guard);
        list_foreach(*get_list(instance, address), iterator) {
                endpoint_t *ep = endpoint_get_instance(iterator);
                if (ep->address == address) {
                        iterator = iterator->next;
                        list_remove(&ep->link);
                        if (callback)
                                callback(ep, arg);
                        endpoint_destroy(ep);
                }
        }
        fibril_mutex_unlock(&instance->guard);
}
/**
 * @}
 */