tmk_keyboard/tool/mbed/mbed-sdk/libraries/USBDevice/USBMIDI/USBMIDI.cpp

/* Copyright (c) 2010-2011 mbed.org, MIT License
*
* 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 "stdint.h"
#include "USBMIDI.h"


USBMIDI::USBMIDI(uint16_t vendor_id, uint16_t product_id, uint16_t product_release)
 : USBDevice(vendor_id, product_id, product_release), cur_data(0), data_end(true)
{
    midi_evt = NULL;
    USBDevice::connect();
}

// write plain MIDIMessage that will be converted to USBMidi event packet
void USBMIDI::write(MIDIMessage m) {
    // first byte keeped for retro-compatibility
    for(int p=1; p < m.length; p+=3) {
        uint8_t buf[4];
        // Midi message to USBMidi event packet
        buf[0]=m.data[1] >> 4;
        // SysEx
        if(buf[0] == 0xF) {
            if((m.length - p) > 3) {
                // SysEx start or continue
                buf[0]=0x4;
            } else {
                switch(m.length - p) {
                    case 1:
                        // SysEx end with one byte
                        buf[0]=0x5;
                        break;
                    case 2:
                        // SysEx end with two bytes
                        buf[0]=0x6;
                        break;
                    case 3:
                        // SysEx end with three bytes
                        buf[0]=0x7;
                        break;
                }
            }
        }
        buf[1]=m.data[p];

        if(p+1 < m.length)
            buf[2]=m.data[p+1];
        else
            buf[2]=0;

        if(p+2 < m.length)
            buf[3]=m.data[p+2];
        else
            buf[3]=0;

        USBDevice::write(EPBULK_IN, buf, 4, MAX_PACKET_SIZE_EPBULK);
    }
}


void USBMIDI::attach(void (*fptr)(MIDIMessage)) {
    midi_evt = fptr;
}

bool USBMIDI::EPBULK_OUT_callback() {
    uint8_t buf[64];
    uint32_t len;
    readEP(EPBULK_OUT, buf, &len, 64);

    if (midi_evt != NULL) {
        for (uint32_t i=0; i<len; i+=4) {   
            uint8_t data_read;
            data_end=true;
            switch(buf[i]) {
            case 0x2:
                // Two-bytes System Common Message - undefined in USBMidi 1.0
                data_read=2;
                break;
            case 0x4:
                // SysEx start or continue
                data_end=false;
                data_read=3;
                break;
            case 0x5:
                 // Single-byte System Common Message or SysEx end with one byte
                data_read=1;
                break;
            case 0x6:
                // SysEx end with two bytes
                data_read=2;
                break;
            case 0xC:
                // Program change
                data_read=2;
                break;
            case 0xD:
                // Channel pressure
                data_read=2;
                break;      
            case 0xF:
                // Single byte
                data_read=1;
                break;    
            default:
                // Others three-bytes messages
                data_read=3;
                break;      
            } 
        
            for(uint8_t j=1;j<data_read+1;j++) {
                data[cur_data]=buf[i+j];
                cur_data++;
            }
        
            if(data_end) {
                 midi_evt(MIDIMessage(data,cur_data));
                 cur_data=0;            
            }
       }
    }

    // We reactivate the endpoint to receive next characters
    readStart(EPBULK_OUT, MAX_PACKET_SIZE_EPBULK);
    return true;
}

// Called in ISR context
// Set configuration. Return false if the
// configuration is not supported.
bool USBMIDI::USBCallback_setConfiguration(uint8_t configuration) {
    if (configuration != DEFAULT_CONFIGURATION) {
        return false;
    }

    // Configure endpoints > 0
    addEndpoint(EPBULK_IN, MAX_PACKET_SIZE_EPBULK);
    addEndpoint(EPBULK_OUT, MAX_PACKET_SIZE_EPBULK);

    // We activate the endpoint to be able to receive data
    readStart(EPBULK_OUT, MAX_PACKET_SIZE_EPBULK);
    return true;
}


uint8_t * USBMIDI::stringIinterfaceDesc() {
    static uint8_t stringIinterfaceDescriptor[] = {
        0x0c,                           //bLength
        STRING_DESCRIPTOR,              //bDescriptorType 0x03
        'A',0,'u',0,'d',0,'i',0,'o',0   //bString iInterface - Audio
    };
    return stringIinterfaceDescriptor;
}

uint8_t * USBMIDI::stringIproductDesc() {
    static uint8_t stringIproductDescriptor[] = {
        0x16,                                                       //bLength
        STRING_DESCRIPTOR,                                          //bDescriptorType 0x03
        'M',0,'b',0,'e',0,'d',0,' ',0,'A',0,'u',0,'d',0,'i',0,'o',0 //bString iProduct - Mbed Audio
    };
    return stringIproductDescriptor;
}


uint8_t * USBMIDI::configurationDesc() {
    static uint8_t configDescriptor[] = {
        // configuration descriptor
        0x09, 0x02, 0x65, 0x00, 0x02, 0x01, 0x00, 0xc0, 0x50,

        // The Audio Interface Collection
        0x09, 0x04, 0x00, 0x00, 0x00, 0x01, 0x01, 0x00, 0x00, // Standard AC Interface Descriptor
        0x09, 0x24, 0x01, 0x00, 0x01, 0x09, 0x00, 0x01, 0x01, // Class-specific AC Interface Descriptor
        0x09, 0x04, 0x01, 0x00, 0x02, 0x01, 0x03, 0x00, 0x00, // MIDIStreaming Interface Descriptors
        0x07, 0x24, 0x01, 0x00, 0x01, 0x41, 0x00,             // Class-Specific MS Interface Header Descriptor

        // MIDI IN JACKS
        0x06, 0x24, 0x02, 0x01, 0x01, 0x00,
        0x06, 0x24, 0x02, 0x02, 0x02, 0x00,

        // MIDI OUT JACKS
        0x09, 0x24, 0x03, 0x01, 0x03, 0x01, 0x02, 0x01, 0x00,
        0x09, 0x24, 0x03, 0x02, 0x06, 0x01, 0x01, 0x01, 0x00,

        // OUT endpoint descriptor
        0x09, 0x05, 0x02, 0x02, 0x40, 0x00, 0x00, 0x00, 0x00,
        0x05, 0x25, 0x01, 0x01, 0x01,

        // IN endpoint descriptor
        0x09, 0x05, 0x82, 0x02, 0x40, 0x00, 0x00, 0x00, 0x00,
        0x05, 0x25, 0x01, 0x01, 0x03,
    };
    return configDescriptor;
}