source: mainline/uspace/lib/usbvirt/src/stdreq.c@ 56b962d

/*
 * 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 usb
 * @{
 */
/** @file
 * @brief Preprocessing of standard device requests.
 */
#include <errno.h>
#include <stdlib.h>
#include <mem.h>
#include <usb/devreq.h>

#include "private.h"


typedef int (*usbvirt_stdreq_handler_t)(usbvirt_device_t *,
usb_device_request_setup_packet_t *, uint8_t *);

/*
 * All sub handlers must return EFORWARD to inform the caller that
 * they were not able to process the request (yes, it is abuse of
 * this error code but such error code shall not collide with anything
 * else in this context).
 */
 
/** GET_DESCRIPTOR handler. */
static int handle_get_descriptor(usbvirt_device_t *device,
    usb_device_request_setup_packet_t *setup_packet, uint8_t *extra_data)
{
        uint8_t type = setup_packet->value_high;
        uint8_t index = setup_packet->value_low;

        /* 
         * Standard device descriptor.
         */
        if ((type == USB_DESCTYPE_DEVICE) && (index == 0)) {
                if (device->descriptors && device->descriptors->device) {
                        return device->control_transfer_reply(device, 0,
                            device->descriptors->device,
                            device->descriptors->device->length);
                } else {
                        return EFORWARD;
                }
        }
        
        /*
         * Configuration descriptor together with interface, endpoint and
         * class-specific descriptors.
         */
        if (type == USB_DESCTYPE_CONFIGURATION) {
                if (!device->descriptors) {
                        return EFORWARD;
                }
                if (index >= device->descriptors->configuration_count) {
                        return EFORWARD;
                }
                /* Copy the data. */
                usbvirt_device_configuration_t *config = &device->descriptors
                    ->configuration[index];
                uint8_t *all_data = malloc(config->descriptor->total_length);
                if (all_data == NULL) {
                        return ENOMEM;
                }
                
                uint8_t *ptr = all_data;
                memcpy(ptr, config->descriptor, config->descriptor->length);
                ptr += config->descriptor->length;
                size_t i;
                for (i = 0; i < config->extra_count; i++) {
                        usbvirt_device_configuration_extras_t *extra
                            = &config->extra[i];
                        memcpy(ptr, extra->data, extra->length);
                        ptr += extra->length;
                }
                
                int rc = device->control_transfer_reply(device, 0,
                    all_data, config->descriptor->total_length);
                
                free(all_data);
                
                return rc;
        }
        
        return EFORWARD;
}

/** SET_ADDRESS handler. */
static int handle_set_address(usbvirt_device_t *device,
    usb_device_request_setup_packet_t *setup_packet, uint8_t *extra_data)
{
        uint16_t new_address = setup_packet->value;
        uint16_t zero1 = setup_packet->index;
        uint16_t zero2 = setup_packet->length;

        if ((zero1 != 0) || (zero2 != 0)) {
                return EINVAL;
        }
        
        if (new_address > 127) {
                return EINVAL;
        }
        
        device->new_address = new_address;
        
        return EOK;
}

/** SET_CONFIGURATION handler. */
static int handle_set_configuration(usbvirt_device_t *device,
    usb_device_request_setup_packet_t *setup_packet, uint8_t *extra_data)
{
        uint16_t configuration_value = setup_packet->value;
        uint16_t zero1 = setup_packet->index;
        uint16_t zero2 = setup_packet->length;

        if ((zero1 != 0) || (zero2 != 0)) {
                return EINVAL;
        }
        
        /*
         * Configuration value is 1 byte information.
         */
        if (configuration_value > 255) {
                return EINVAL;
        }
        
        /*
         * Do nothing when in default state. According to specification,
         * this is not specified.
         */
        if (device->state == USBVIRT_STATE_DEFAULT) {
                return EOK;
        }
        
        if (configuration_value == 0) {
                device->state = USBVIRT_STATE_ADDRESS;
        } else {
                /*
                * TODO: browse provided configurations and verify that
                * user selected existing configuration.
                */
                device->state = USBVIRT_STATE_CONFIGURED;
                if (device->descriptors) {
                        device->descriptors->current_configuration
                            = configuration_value;
                }
        }
                
        return EOK;
}

static usbvirt_stdreq_handler_t local_handlers[USB_DEVREQ_LAST_STD] = {
        [USB_DEVREQ_GET_DESCRIPTOR] = handle_get_descriptor,
        [USB_DEVREQ_SET_ADDRESS] = handle_set_address,
        [USB_DEVREQ_SET_CONFIGURATION] = handle_set_configuration
};

/** Handle standard device request. */
int handle_std_request(usbvirt_device_t *device,
    usb_device_request_setup_packet_t *request_packet, uint8_t *data)
{
        int request = request_packet->request;

        device->lib_debug(device, 3, USBVIRT_DEBUGTAG_CONTROL_PIPE_ZERO,
            "handling standard request %d", request);

        if (request >= USB_DEVREQ_LAST_STD) {
                return ENOTSUP;
        }
        
        int rc = EFORWARD;
        if ((device->ops)
            && (device->ops->on_standard_request[request])) {
                rc = device->ops->on_standard_request[request](device,
                    request_packet, data);
        }

        if (rc == EFORWARD) {
                if (local_handlers[request]) {
                        rc = local_handlers[request](device,
                            request_packet, data);
                } else {
                        rc = ENOTSUP;
                }
        }

        assert(rc != EFORWARD);
        return rc;
}

/**
 * @}
 */