keyboard/qmk/lib/vusb/examples/hid-custom-rq/firmware/main.c

/* Name: main.c
 * Project: hid-custom-rq example
 * Author: Christian Starkjohann
 * Creation Date: 2008-04-07
 * Tabsize: 4
 * Copyright: (c) 2008 by OBJECTIVE DEVELOPMENT Software GmbH
 * License: GNU GPL v2 (see License.txt), GNU GPL v3 or proprietary (CommercialLicense.txt)
 */

/*
This example should run on most AVRs with only little changes. No special
hardware resources except INT0 are used. You may have to change usbconfig.h for
different I/O pins for USB. Please note that USB D+ must be the INT0 pin, or
at least be connected to INT0 as well.
We assume that an LED is connected to port B bit 0. If you connect it to a
different port or bit, change the macros below:
*/
#define LED_PORT_DDR        DDRB
#define LED_PORT_OUTPUT     PORTB
#define LED_BIT             0

#include <avr/io.h>
#include <avr/wdt.h>
#include <avr/interrupt.h>  /* for sei() */
#include <util/delay.h>     /* for _delay_ms() */

#include <avr/pgmspace.h>   /* required by usbdrv.h */
#include "usbdrv.h"
#include "oddebug.h"        /* This is also an example for using debug macros */
#include "requests.h"       /* The custom request numbers we use */

/* ------------------------------------------------------------------------- */
/* ----------------------------- USB interface ----------------------------- */
/* ------------------------------------------------------------------------- */

PROGMEM const char usbHidReportDescriptor[22] = {   /* USB report descriptor */
    0x06, 0x00, 0xff,              // USAGE_PAGE (Generic Desktop)
    0x09, 0x01,                    // USAGE (Vendor Usage 1)
    0xa1, 0x01,                    // COLLECTION (Application)
    0x15, 0x00,                    //   LOGICAL_MINIMUM (0)
    0x26, 0xff, 0x00,              //   LOGICAL_MAXIMUM (255)
    0x75, 0x08,                    //   REPORT_SIZE (8)
    0x95, 0x01,                    //   REPORT_COUNT (1)
    0x09, 0x00,                    //   USAGE (Undefined)
    0xb2, 0x02, 0x01,              //   FEATURE (Data,Var,Abs,Buf)
    0xc0                           // END_COLLECTION
};
/* The descriptor above is a dummy only, it silences the drivers. The report
 * it describes consists of one byte of undefined data.
 * We don't transfer our data through HID reports, we use custom requests
 * instead.
 */

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

usbMsgLen_t usbFunctionSetup(uchar data[8])
{
usbRequest_t    *rq = (void *)data;

    if((rq->bmRequestType & USBRQ_TYPE_MASK) == USBRQ_TYPE_VENDOR){
        DBG1(0x50, &rq->bRequest, 1);   /* debug output: print our request */
        if(rq->bRequest == CUSTOM_RQ_SET_STATUS){
            if(rq->wValue.bytes[0] & 1){    /* set LED */
                LED_PORT_OUTPUT |= _BV(LED_BIT);
            }else{                          /* clear LED */
                LED_PORT_OUTPUT &= ~_BV(LED_BIT);
            }
        }else if(rq->bRequest == CUSTOM_RQ_GET_STATUS){
            static uchar dataBuffer[1];     /* buffer must stay valid when usbFunctionSetup returns */
            dataBuffer[0] = ((LED_PORT_OUTPUT & _BV(LED_BIT)) != 0);
            usbMsgPtr = dataBuffer;         /* tell the driver which data to return */
            return 1;                       /* tell the driver to send 1 byte */
        }
    }else{
        /* calss requests USBRQ_HID_GET_REPORT and USBRQ_HID_SET_REPORT are
         * not implemented since we never call them. The operating system
         * won't call them either because our descriptor defines no meaning.
         */
    }
    return 0;   /* default for not implemented requests: return no data back to host */
}

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

int __attribute__((noreturn)) main(void)
{
uchar   i;

    wdt_enable(WDTO_1S);
    /* If you don't use the watchdog, replace the call above with a wdt_disable().
     * On newer devices, the status of the watchdog (on/off, period) is PRESERVED
     * OVER RESET!
     */
    /* RESET status: all port bits are inputs without pull-up.
     * That's the way we need D+ and D-. Therefore we don't need any
     * additional hardware initialization.
     */
    odDebugInit();
    DBG1(0x00, 0, 0);       /* debug output: main starts */
    usbInit();
    usbDeviceDisconnect();  /* enforce re-enumeration, do this while interrupts are disabled! */
    i = 0;
    while(--i){             /* fake USB disconnect for > 250 ms */
        wdt_reset();
        _delay_ms(1);
    }
    usbDeviceConnect();
    LED_PORT_DDR |= _BV(LED_BIT);   /* make the LED bit an output */
    sei();
    DBG1(0x01, 0, 0);       /* debug output: main loop starts */
    for(;;){                /* main event loop */
#if 0   /* this is a bit too aggressive for a debug output */
        DBG2(0x02, 0, 0);   /* debug output: main loop iterates */
#endif
        wdt_reset();
        usbPoll();
    }
}

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