source: mainline/uspace/lib/usbhid/src/hidreport.c@ 7d521e24

/*
 * Copyright (c) 2011 Lubos Slovak
 * 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 HID keyboard device structure and API.
 */

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

#include <usb/debug.h>
#include <usb/classes/hidparser.h>
#include <usb/dev/dp.h>
#include <usb/dev/driver.h>
#include <usb/dev/pipes.h>
#include <usb/classes/hid.h>
#include <usb/descriptor.h>
#include <usb/dev/request.h>

#include <usb/classes/hidreport.h>

static int usb_hid_get_report_descriptor(usb_device_t *dev, 
    uint8_t **report_desc, size_t *size)
{
        assert(report_desc != NULL);
        assert(size != NULL);
        
        usb_dp_parser_t parser =  {
                .nesting = usb_dp_standard_descriptor_nesting
        };
        
        usb_dp_parser_data_t parser_data = {
                .data = dev->descriptors.configuration,
                .size = dev->descriptors.configuration_size,
                .arg = NULL
        };
        
        /*
         * First nested descriptor of the configuration descriptor.
         */
        uint8_t *d = 
            usb_dp_get_nested_descriptor(&parser, &parser_data, 
            dev->descriptors.configuration);
        
        /*
         * Find the interface descriptor corresponding to our interface number.
         */
        int i = 0;
        while (d != NULL && i < dev->interface_no) {
                d = usb_dp_get_sibling_descriptor(&parser, &parser_data, 
                    dev->descriptors.configuration, d);
                ++i;
        }
        
        if (d == NULL) {
                usb_log_error("The %d. interface descriptor not found!\n",
                    dev->interface_no);
                return ENOENT;
        }
        
        /*
         * First nested descriptor of the interface descriptor.
         */
        uint8_t *iface_desc = d;
        d = usb_dp_get_nested_descriptor(&parser, &parser_data, iface_desc);
        
        /*
         * Search through siblings until the HID descriptor is found.
         */
        while (d != NULL && *(d + 1) != USB_DESCTYPE_HID) {
                d = usb_dp_get_sibling_descriptor(&parser, &parser_data, 
                    iface_desc, d);
        }
        
        if (d == NULL) {
                usb_log_fatal("No HID descriptor found!\n");
                return ENOENT;
        }
        
        if (*d != sizeof(usb_standard_hid_descriptor_t)) {
                usb_log_error("HID descriptor has wrong size (%u, expected %zu"
                    ")\n", *d, sizeof(usb_standard_hid_descriptor_t));
                return EINVAL;
        }
        
        usb_standard_hid_descriptor_t *hid_desc = 
            (usb_standard_hid_descriptor_t *)d;
        
        uint16_t length =  hid_desc->report_desc_info.length;
        size_t actual_size = 0;

        /*
         * Allocate space for the report descriptor.
         */
        *report_desc = (uint8_t *)malloc(length);
        if (*report_desc == NULL) {
                usb_log_error("Failed to allocate space for Report descriptor."
                    "\n");
                return ENOMEM;
        }
        
        usb_log_debug("Getting Report descriptor, expected size: %u\n", length);
        
        /*
         * Get the descriptor from the device.
         */
        int rc = usb_request_get_descriptor(&dev->ctrl_pipe,
            USB_REQUEST_TYPE_STANDARD, USB_REQUEST_RECIPIENT_INTERFACE,
            USB_DESCTYPE_HID_REPORT, 0, dev->interface_no,
            *report_desc, length, &actual_size);

        if (rc != EOK) {
                free(*report_desc);
                *report_desc = NULL;
                return rc;
        }

        if (actual_size != length) {
                free(*report_desc);
                *report_desc = NULL;
                usb_log_error("Report descriptor has wrong size (%zu, expected "
                    "%u)\n", actual_size, length);
                return EINVAL;
        }
        
        *size = length;
        
        usb_log_debug("Done.\n");
        
        return EOK;
}

/*----------------------------------------------------------------------------*/

int usb_hid_process_report_descriptor(usb_device_t *dev, 
    usb_hid_report_t *report)
{
        if (dev == NULL || report == NULL) {
                usb_log_error("Failed to process Report descriptor: wrong "
                    "parameters given.\n");
                return EINVAL;
        }
        
        uint8_t *report_desc = NULL;
        size_t report_size;
        
        int rc = usb_hid_get_report_descriptor(dev, &report_desc, 
            &report_size);
        
        if (rc != EOK) {
                usb_log_error("Problem with getting Report descriptor: %s.\n",
                    str_error(rc));
                if (report_desc != NULL) {
                        free(report_desc);
                }
                return rc;
        }
        
        assert(report_desc != NULL);
        
        rc = usb_hid_parse_report_descriptor(report, report_desc, report_size);
        if (rc != EOK) {
                usb_log_error("Problem parsing Report descriptor: %s.\n",
                    str_error(rc));
                free(report_desc);
                return rc;
        }
        
        usb_hid_descriptor_print(report);
        free(report_desc);
        
        return EOK;
}

/**
 * @}
 */