usbconfig.c

#include "usbdrv/usbdrv.h"
#include <avr/interrupt.h>



/* USB device descriptor */
const PROGMEM uchar deviceDescrMIDI[] = 
{
	18,			/* sizeof(usbDescriptorDevice): length of descriptor in bytes */
	USBDESCR_DEVICE,	/* descriptor type */
	0x10, 0x01,		/* USB version supported */
	0,			/* device class: defined at interface level */
	0,			/* subclass */
	0,			/* protocol */
	8,			/* max packet size */
	USB_CFG_VENDOR_ID,	/* 2 bytes */
	USB_CFG_DEVICE_ID,	/* 2 bytes */
	USB_CFG_DEVICE_VERSION,	/* 2 bytes */
	1,			/* manufacturer string index */
	2,			/* product string index */
	0,			/* serial number string index */
	1,			/* number of configurations */
};

/* USB configuration descriptor */
const PROGMEM uchar configDescrMIDI[] =
{
	9,			/* sizeof(usbDescrConfig): length of descriptor in bytes */
	USBDESCR_CONFIG,	/* descriptor type */
	101, 0,			/* total length of data returned (including inlined descriptors) */
	2,			/* number of interfaces in this configuration */
	1,			/* index of this configuration */
	0,			/* configuration name string index */
	0,
	/* USBATTR_BUSPOWER, */
	USB_CFG_MAX_BUS_POWER / 2,	/* max USB current in 2mA units */

	/* B.3 AudioControl Interface Descriptors
	The AudioControl interface describes the device structure (audio function topology)
	and is used to manipulate the Audio Controls. This device has no audio function
	incorporated. However, the AudioControl interface is mandatory and therefore both
	the standard AC interface descriptor and the classspecific AC interface descriptor
	must be present. The class-specific AC interface descriptor only contains the header
	descriptor. */

	/* B.3.1 Standard AC Interface Descriptor
	The AudioControl interface has no dedicated endpoints associated with it. It uses the
	default pipe (endpoint 0) for all communication purposes. Class-specific AudioControl
	Requests are sent using the default pipe. There is no Status Interrupt endpoint provided. */

	/* AC interface descriptor follows inline: */
	9,			/* sizeof(usbDescrInterface): length of descriptor in bytes */
	USBDESCR_INTERFACE,	/* descriptor type */
	0,			/* index of this interface */
	0,			/* alternate setting for this interface */
	0,			/* endpoints excl 0: number of endpoint descriptors to follow */
	1,			/* */
	1,			/* */
	0,			/* */
	0,			/* string index for interface */

	/* B.3.2 Class-specific AC Interface Descriptor
	The Class-specific AC interface descriptor is always headed by a Header descriptor
	that contains general information about the AudioControl interface. It contains all
	the pointers needed to describe the Audio Interface Collection, associated with the
	described audio function. Only the Header descriptor is present in this device
	because it does not contain any audio functionality as such. */
	/* AC Class-Specific descriptor */
	9,			/* sizeof(usbDescrCDC_HeaderFn): length of descriptor in bytes */
	36,			/* descriptor type */
	1,			/* header functional descriptor */
	0x0, 0x01,		/* bcdADC */
	9, 0,			/* wTotalLength */
	1,			/* */
	1,			/* */

	/* B.4 MIDIStreaming Interface Descriptors */

	/* B.4.1 Standard MS Interface Descriptor */
	/* interface descriptor follows inline: */
	9,			/* length of descriptor in bytes */
	USBDESCR_INTERFACE,	/* descriptor type */
	1,			/* index of this interface */
	0,			/* alternate setting for this interface */
	2,			/* endpoints excl 0: number of endpoint descriptors to follow */
	1,			/* AUDIO */
	3,			/* MS */
	0,			/* unused */
	0,			/* string index for interface */

	/* B.4.2 Class-specific MS Interface Descriptor */
	/* MS Class-Specific descriptor */
	7,			/* length of descriptor in bytes */
	36,			/* descriptor type */
	1,			/* header functional descriptor */
	0x0, 0x01,		/* bcdADC */
	65, 0,			/* wTotalLength */

	/* B.4.3 MIDI IN Jack Descriptor */
	6,			/* bLength */
	36,			/* descriptor type */
	2,			/* MIDI_IN_JACK desc subtype */
	1,			/* EMBEDDED bJackType */
	1,			/* bJackID */
	0,			/* iJack */

	6,			/* bLength */
	36,			/* descriptor type */
	2,			/* MIDI_IN_JACK desc subtype */
	2,			/* EXTERNAL bJackType */
	2,			/* bJackID */
	0,			/* iJack */

	/* B.4.4 MIDI OUT Jack Descriptor */
	9,			/* length of descriptor in bytes */
	36,			/* descriptor type */
	3,			/* MIDI_OUT_JACK descriptor */
	1,			/* EMBEDDED bJackType */
	3,			/* bJackID */
	1,			/* No of input pins */
	2,			/* BaSourceID */
	1,			/* BaSourcePin */
	0,			/* iJack */

	9,			/* bLength of descriptor in bytes */
	36,			/* bDescriptorType */
	3,			/* MIDI_OUT_JACK bDescriptorSubtype */
	2,			/* EXTERNAL bJackType */
	4,			/* bJackID */
	1,			/* bNrInputPins */
	1,			/* baSourceID (0) */
	1,			/* baSourcePin (0) */
	0,			/* iJack */


	/* B.5 Bulk OUT Endpoint Descriptors */

	/* B.5.1 Standard Bulk OUT Endpoint Descriptor */
	9,			/* bLenght */
	USBDESCR_ENDPOINT,	/* bDescriptorType = endpoint */
	0x1,			/* bEndpointAddress OUT endpoint number 1 */
	3,			/* bmAttributes: 2:Bulk, 3:Interrupt endpoint */
	8, 0,			/* wMaxPacketSize */
	10,			/* bIntervall in ms */
	0,			/* bRefresh */
	0,			/* bSyncAddress */

	/* B.5.2 Class-specific MS Bulk OUT Endpoint Descriptor */
	5,			/* bLength of descriptor in bytes */
	37,			/* bDescriptorType */
	1,			/* bDescriptorSubtype */
	1,			/* bNumEmbMIDIJack */
	1,			/* baAssocJackID (0) */


	/* B.6 Bulk IN Endpoint Descriptors */

	/* B.6.1 Standard Bulk IN Endpoint Descriptor */
	9,			/* bLenght */
	USBDESCR_ENDPOINT,	/* bDescriptorType = endpoint */
	0x81,			/* bEndpointAddress IN endpoint number 1 */
	3,			/* bmAttributes: 2: Bulk, 3: Interrupt endpoint */
	8, 0,			/* wMaxPacketSize */
	10,			/* bIntervall in ms */
	0,			/* bRefresh */
	0,			/* bSyncAddress */

	/* B.6.2 Class-specific MS Bulk IN Endpoint Descriptor */
	5,			/* bLength of descriptor in bytes */
	37,			/* bDescriptorType */
	1,			/* bDescriptorSubtype */
	1,			/* bNumEmbMIDIJack (0) */
	3,			/* baAssocJackID (0) */
};

uchar usbFunctionDescriptor(usbRequest_t * rq)
{
	if (rq->wValue.bytes[1] == USBDESCR_DEVICE) {
		usbMsgPtr = (uchar *) deviceDescrMIDI;
		return sizeof(deviceDescrMIDI);
	}
	else {		/* must be config descriptor */
		usbMsgPtr = (uchar *) configDescrMIDI;
		return sizeof(configDescrMIDI);
	}
}

uchar usbFunctionSetup(uchar *data)
{
	(void)data;
	return 0;
}


static void calibrateOscillator(void)
{
	uchar step = 128, trialValue = 0, optimumValue;
	int x, optimumDev, targetValue = (unsigned)(1499 * (double)F_CPU / 10.5e6 + 0.5);

	/* do a binary search: */
	do
	{
		OSCCAL = trialValue + step;
		x = usbMeasureFrameLength();	/* proportional to current real frequency */
		if(x < targetValue)		/* frequency still too low */
			trialValue += step;
		step >>= 1;
	}
	while(step > 0);

	/* We have a precision of +/- 1 for optimum OSCCAL here */
	/* now do a neighborhood search for optimum value */

	optimumValue = trialValue;

	optimumDev = x; /* this is certainly far away from optimum */

	for(OSCCAL = trialValue - 1; OSCCAL <= trialValue + 1; OSCCAL++)
	{
		x = usbMeasureFrameLength() - targetValue;

		if(x < 0) x = -x;	/* absolute value */

		if(x < optimumDev)
		{
			optimumDev = x;
			optimumValue = OSCCAL;
		}
	}
	OSCCAL = optimumValue;
}

void usbEventResetReady(void)
{
	/* Disable interrupts during oscillator calibration since
	the usbMeasureFrameLength function counts CPU cycles. */
	cli();
	calibrateOscillator();
	sei();
}