AIOC/stm32/aioc-fw/Src/usb_descriptors.c

/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2019 Ha Thach (tinyusb.org)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 */
#include "tusb.h"
#include "usb_descriptors.h"
#include "stm32f3xx_hal.h"

/* A combination of interfaces must have a unique product id, since PC will save device driver after the first plug.
 * Same VID/PID with different interface e.g MSC (first), then CDC (later) will possibly cause system error on PC.
 *
 * Auto ProductID layout's Bitmap:
 *   [MSB]       MIDI | HID | MSC | CDC          [LSB]
 */
#define _PID_MAP(itf, n)  ( (CFG_TUD_##itf) << (n) )
#define USB_PID           (0x4000 | _PID_MAP(CDC, 0) | _PID_MAP(MSC, 1) | _PID_MAP(HID, 2) | \
                           _PID_MAP(MIDI, 3) | _PID_MAP(VENDOR, 4) | _PID_MAP(AUDIO, 5))

#define USB_VID   0xCafe
#define USB_BCD   0x0200

//--------------------------------------------------------------------+
// Device Descriptors
//--------------------------------------------------------------------+
tusb_desc_device_t const desc_device =
{
    .bLength            = sizeof(tusb_desc_device_t),
    .bDescriptorType    = TUSB_DESC_DEVICE,
    .bcdUSB             = USB_BCD,

    // Use Interface Association Descriptor (IAD) for CDC
    // As required by USB Specs IAD's subclass must be common class (2) and protocol must be IAD (1)
    .bDeviceClass       = TUSB_CLASS_MISC,
    .bDeviceSubClass    = MISC_SUBCLASS_COMMON,
    .bDeviceProtocol    = MISC_PROTOCOL_IAD,
    .bMaxPacketSize0    = CFG_TUD_ENDPOINT0_SIZE,

    .idVendor           = USB_VID,
    .idProduct          = USB_PID,
    .bcdDevice          = 0x0100,

    .iManufacturer      = STR_IDX_MANUFACTURER,
    .iProduct           = STR_IDX_PRODUCT,
    .iSerialNumber      = STR_IDX_SERIAL,

    .bNumConfigurations = 0x01
};

// Invoked when received GET DEVICE DESCRIPTOR
// Application return pointer to descriptor
uint8_t const * tud_descriptor_device_cb(void)
{
  return (uint8_t const *) &desc_device;
}

//--------------------------------------------------------------------+
// Configuration Descriptor
//--------------------------------------------------------------------+
#define CONFIG_TOTAL_LEN    (TUD_CONFIG_DESC_LEN + CFG_TUD_CDC * TUD_CDC_DESC_LEN + 1 * TUD_AUDIO_IO_DESC_LEN)

uint8_t const desc_fs_configuration[] =
{
  // Config number, interface count, string index, total length, attribute, power in mA
  TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, 0x00, 100),
  TUD_CDC_DESCRIPTOR(ITF_NUM_CDC_0, STR_IDX_CDCITF, EPNUM_CDC_0_NOTIF, 8, EPNUM_CDC_0_OUT, EPNUM_CDC_0_IN, CFG_TUD_CDC_EP_BUFSIZE),
  TUD_AUDIO_IO_DESCRIPTOR(/*_itfnum*/ ITF_NUM_AUDIO_CONTROL, /*_stridx*/ STR_IDX_AUDIOITF, /*_nBytesPerSample*/ CFG_TUD_AUDIO_FUNC_1_N_BYTES_PER_SAMPLE, /*_nBitsUsedPerSample*/ CFG_TUD_AUDIO_FUNC_1_N_BYTES_PER_SAMPLE*8, /*_epin*/ EPNUM_AUDIO_IN, /*_epinsize*/ CFG_TUD_AUDIO_FUNC_1_EP_IN_SZ_MAX, /*_epout*/ EPNUM_AUDIO_OUT, /*_epoutsize*/ CFG_TUD_AUDIO_FUNC_1_EP_OUT_SZ_MAX, /*_epfb*/ EPNUM_AUDIO_FB)
};

// Invoked when received GET CONFIGURATION DESCRIPTOR
// Application return pointer to descriptor
// Descriptor contents must exist long enough for transfer to complete
uint8_t const * tud_descriptor_configuration_cb(uint8_t index)
{
  (void) index; // for multiple configurations

  TU_ASSERT(!TUD_OPT_HIGH_SPEED);
  return desc_fs_configuration;
}

//--------------------------------------------------------------------+
// String Descriptors
//--------------------------------------------------------------------+
static uint32_t crc32(const uint8_t * buf_ptr, uint32_t buf_len)
{
    /* Generate a serial number from processor UID using CRC32 */
    const uint32_t crc32_init = 0xFFFFFFFFUL;
    const uint32_t crc32_poly = 0xEDB88320UL;
    uint32_t serial = crc32_init; /* CRC32 Initial value */

    while (buf_len-- > 0) {
       uint8_t byte = *buf_ptr++;
       serial = serial ^ byte;
       for (uint8_t j=0; j<8; j++) {
          uint32_t mask = -(serial & 1);
          serial = (serial >> 1) ^ (crc32_poly & mask);
       }
    }

    return ~serial;
}

static const char * get_serial(void)
{
    static char serial_str[sizeof(uint32_t) * 2 + 1];
    uint32_t serial_num = crc32((uint8_t *) UID_BASE, 12);

    for (uint8_t i=0; i<(sizeof(uint32_t) * 2); i++) {
        uint8_t nibble = ((serial_num & 0xF0000000UL) >> 28);
        serial_str[i] = nibble < 0xA ? nibble + '0' : nibble - 0xA + 'a';
        serial_num <<= 4;
    }

    return serial_str;
}

static uint8_t ascii_to_utf16(uint8_t * buffer, uint32_t size, const char * str)
{
    uint8_t len = 0;

    while ( (*str != '\0') && (size > 0) ) {
        *buffer++ = *str++;
        *buffer++ = 0x00;
        size -= 2;
        len += 2;
    }

    return len;
}

// Invoked when received GET STRING DESCRIPTOR request
// Application return pointer to descriptor, whose contents must exist long enough for transfer to complete
uint8_t const * tud_descriptor_string_cb(uint8_t index, uint16_t langid)
{
  (void) langid;
  static uint8_t buffer[64];
  uint8_t * ptr = &buffer[2];
  uint8_t len = sizeof(buffer) - 2;

  switch (index) {
  case STR_IDX_LANGUAGE:
      ptr[0] = 0x09; ptr[1] = 0x04;
      len = 2;
      break;

  case STR_IDX_MANUFACTURER:
      len = ascii_to_utf16(ptr, len, USB_STRING_MANUFACTURER);
      break;

  case STR_IDX_PRODUCT:
      len = ascii_to_utf16(ptr, len, USB_STRING_PRODUCT);
      break;

  case STR_IDX_SERIAL:
      len = ascii_to_utf16(ptr, len, get_serial());
      break;

  case STR_IDX_CDCITF:
      len = ascii_to_utf16(ptr, len, USB_STRING_CDCITF);
      break;

  case STR_IDX_AUDIOITF:
      len = ascii_to_utf16(ptr, len, USB_STRING_AUDIOITF);
      break;

  case STR_IDX_AUDIOIN:
      len = ascii_to_utf16(ptr, len, USB_STRING_AUDIOIN);
      break;

  case STR_IDX_AUDIOOUT:
      len = ascii_to_utf16(ptr, len, USB_STRING_AUDIOOUT);
      break;

  case STR_IDX_AUDIOINVOL:
      len = ascii_to_utf16(ptr, len, USB_STRING_AUDIOINVOL);
      break;

  case STR_IDX_AUDIOOUTVOL:
      len = ascii_to_utf16(ptr, len, USB_STRING_AUDIOOUTVOL);
      break;

  case STR_IDX_AUDIOINCHAN:
      len = ascii_to_utf16(ptr, len, USB_STRING_AUDIOINCHAN);
      break;

  case STR_IDX_AUDIOOUTCHAN:
      len = ascii_to_utf16(ptr, len, USB_STRING_AUDIOOUTCHAN);
      break;

  default:
      TU_ASSERT(0, NULL);
      break;
  }

  buffer[0] = len + 2;
  buffer[1] = TUSB_DESC_STRING;

  return buffer;
}