source: mainline/uspace/lib/usbvirt/src/main.c@ d493ac17

/*
 * Copyright (c) 2010 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 libusbvirt
 * @{
 */
/** @file
 * @brief Device registration with virtual USB framework.
 */
#include <devman.h>
#include <errno.h>
#include <stdlib.h>
#include <mem.h>
#include <assert.h>

#include "private.h"

#define NAMESPACE "usb"

/** Virtual device wrapper. */
typedef struct {
        /** Actual device. */
        usbvirt_device_t *device;
        /** Phone to host controller. */
        int vhcd_phone;
        /** Device id. */
        sysarg_t id;
        /** Linked-list member. */
        link_t link;
} virtual_device_t;

/*** List of known device. */
static LIST_INITIALIZE(device_list);

/** Find virtual device wrapper based on the contents. */
static virtual_device_t *find_device(usbvirt_device_t *device)
{
        if (list_empty(&device_list)) {
                return NULL;
        }
        
        link_t *pos;
        for (pos = device_list.next; pos != &device_list; pos = pos->next) {
                virtual_device_t *dev
                    = list_get_instance(pos, virtual_device_t, link);
                if (dev->device == device) {
                        return dev;
                }
        }
        
        return NULL;
}

/** Find virtual device wrapper by its id. */
static virtual_device_t *find_device_by_id(sysarg_t id)
{
        if (list_empty(&device_list)) {
                return NULL;
        }
        
        link_t *pos;
        for (pos = device_list.next; pos != &device_list; pos = pos->next) {
                virtual_device_t *dev
                    = list_get_instance(pos, virtual_device_t, link);
                if (dev->id == id) {
                        return dev;
                }
        }
        
        return NULL;
}

/** Reply to a control transfer. */
static int control_transfer_reply(usbvirt_device_t *device,
            usb_endpoint_t endpoint, void *buffer, size_t size)
{
        usbvirt_control_transfer_t *transfer = &device->current_control_transfers[endpoint];
        if (transfer->data != NULL) {
                free(transfer->data);
        }
        transfer->data = malloc(size);
        memcpy(transfer->data, buffer, size);
        transfer->data_size = size;
        
        return EOK;
}

/** Initialize virtual device. */
static void device_init(usbvirt_device_t *dev)
{
        dev->transaction_out = transaction_out;
        dev->transaction_setup = transaction_setup;
        dev->transaction_in = transaction_in;
        
        dev->control_transfer_reply = control_transfer_reply;
        
        dev->debug = user_debug;
        dev->lib_debug = lib_debug;
        
        dev->state = USBVIRT_STATE_DEFAULT;
        dev->address = 0;
        dev->new_address = -1;
        
        size_t i;
        for (i = 0; i < USB11_ENDPOINT_MAX; i++) {
                usbvirt_control_transfer_t *transfer = &dev->current_control_transfers[i];
                transfer->direction = 0;
                transfer->request = NULL;
                transfer->request_size = 0;
                transfer->data = NULL;
                transfer->data_size = 0;
        }
}

/** Add a virtual device.
 * The returned device (if not NULL) shall be destroy via destroy_device().
 */
static virtual_device_t *add_device(usbvirt_device_t *dev)
{
        assert(find_device(dev) == NULL);
        virtual_device_t *new_device
            = (virtual_device_t *) malloc(sizeof(virtual_device_t));
        
        new_device->device = dev;
        link_initialize(&new_device->link);
        
        list_append(&new_device->link, &device_list);
        
        return new_device;
}

/** Destroy virtual device. */
static void destroy_device(virtual_device_t *dev)
{
        if (dev->vhcd_phone > 0) {
                async_hangup(dev->vhcd_phone);
        }
        
        list_remove(&dev->link);
        
        free(dev);
}

/** Callback connection handler. */
static void callback_connection(ipc_callid_t iid, ipc_call_t *icall)
{
        // FIXME - determine which device just called back
        virtual_device_t *dev = find_device_by_id(0);
        if (dev == NULL) {
                async_answer_0(iid, EINVAL);
                printf("Ooops\n");
                return;
        }

        device_callback_connection(dev->device, iid, icall);
}

/** Create necessary phones for communication with virtual HCD.
 * This function wraps following calls:
 * -# open <code>/dev/devices/\\virt\\usbhc</code> for reading
 * -# access phone of file opened in previous step
 * -# create callback through just opened phone
 * -# create handler for calling on data from host to function
 * -# return the (outgoing) phone
 *
 * @warning This function is wrapper for several actions and therefore
 * it is not possible - in case of error - to determine at which point
 * error occurred.
 *
 * @param dev Device to connect.
 * @return EOK on success or error code from errno.h.
 */
int usbvirt_connect(usbvirt_device_t *dev)
{
        virtual_device_t *virtual_device = find_device(dev);
        if (virtual_device != NULL) {
                return EEXISTS;
        }
        
        const char *vhc_path = "/virt/usbhc/hc";
        int rc;
        devman_handle_t handle;

        rc = devman_device_get_handle(vhc_path, &handle, 0);
        if (rc != EOK) {
                printf("devman_device_get_handle() failed\n");
                return rc;
        }
        
        int hcd_phone = devman_device_connect(handle, 0);
        
        if (hcd_phone < 0) {
                printf("devman_device_connect() failed\n");
                return hcd_phone;
        }
        
        rc = async_connect_to_me(hcd_phone, 0, 0, 0, callback_connection);
        if (rc != EOK) {
                printf("ipc_connect_to_me() failed\n");
                return rc;
        }
        
        device_init(dev);
        
        virtual_device = add_device(dev);
        virtual_device->vhcd_phone = hcd_phone;
        virtual_device->id = 0;
        
        return EOK;
}

/** Prepares device as local.
 * This is useful if you want to have a virtual device in the same task
 * as HCD.
 *
 * @param dev Device to connect.
 * @return Error code.
 * @retval EOK Device connected.
 * @retval EEXISTS This device is already connected.
 */
int usbvirt_connect_local(usbvirt_device_t *dev)
{
        virtual_device_t *virtual_device = find_device(dev);
        if (virtual_device != NULL) {
                return EEXISTS;
        }
        
        device_init(dev);
        
        virtual_device = add_device(dev);
        virtual_device->vhcd_phone = -1;
        virtual_device->id = 0;
        
        return EOK;
}

/** Disconnects device from HCD.
 *
 * @param dev Device to be disconnected.
 * @return Error code.
 * @retval EOK Device connected.
 * @retval ENOENT This device is not connected.
 */
int usbvirt_disconnect(usbvirt_device_t *dev)
{
        virtual_device_t *virtual_device = find_device(dev);
        if (virtual_device == NULL) {
                return ENOENT;
        }
        
        destroy_device(virtual_device);
        
        return EOK;
}


/**
 * @}
 */