#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>

#include "lights.h"

void init_pwm()
{
	/* Async clock */
	PLLCSR = _BV(PLLE);

	/* Synchronize to the phase lock */
	_delay_ms(1);
	while ((PLLCSR & _BV(PLOCK)) == 0)
		;
	PLLCSR |= _BV(PCKE);

	TCCR1C = _BV(COM1D0) | _BV(COM1D1) | _BV(PWM1D);
	TCCR1A = _BV(COM1A0) | _BV(COM1A1) | _BV(COM1B0) | _BV(COM1B1) | _BV(PWM1A) | _BV(PWM1B);
	TCCR1B = _BV(7)				// PWM1X: PWM inversion mode
		| _BV(CS10) 			// no clock prescaling
		;
	TC1H = 0x01;
	OCR1C = 0xFF;				// TOP value

	TC1H = 0x00;
	OCR1D = OCR1B = OCR1A = 0;		// initial stride is 0

	DDRB  &= ~(_BV( PB1 ) | _BV( PB3 ) | _BV( PB5 )); // tristate it
	PORTB &= ~(_BV( PB1 ) | _BV( PB3 ) | _BV( PB5 )); // set to zero
}

void pwm_on(unsigned char n)
{
	switch (n) {
	case 0: DDRB |= _BV(PB1); break;
	case 1: DDRB |= _BV(PB3); break;
	case 2: DDRB |= _BV(PB5); break;
	}
}

void pwm_off(unsigned char n)
{
	switch (n) {
	case 0: DDRB &= ~_BV(PB1); break;
	case 1: DDRB &= ~_BV(PB3); break;
	case 2: DDRB &= ~_BV(PB5); break;
	}
}

void pwm_set(unsigned char n, unsigned char stride)
{
	TC1H = 0x00;
	switch (n) {
	case 0: OCR1A = stride; break;
	case 1: OCR1B = stride; break;
	case 2: OCR1D = stride; break;
	}
}

#if 0
static void inline pwm_handler()
{
	OCR1A = pwmval[0];
	OCR1B = pwmval[1];
	OCR1D = pwmval[2];
	TIMSK &= ~_BV(TOIE1);
}

ISR(TIMER1_OVF_vect)
{
	pwm_handler();
}
#endif