#include <libopencm3/stm32/gpio.h>
#include <libopencm3/stm32/rcc.h>
#include <libopencm3/stm32/timer.h>

#include <buzzer.h>
#include <macros.h>

struct buzzer buzzers[] = {
	{ TIM2, TIM_OC1 },
};

size_t nbuzzers = count_of(buzzers);

void buzzer_init(struct buzzer *buzzer)
{
	rcc_periph_reset_pulse(buzzer->timer);

	timer_set_mode(buzzer->timer, TIM_CR1_CKD_CK_INT, TIM_CR1_CMS_EDGE,
		TIM_CR1_DIR_UP);

	timer_set_prescaler(buzzer->timer, 72);
	timer_set_repetition_counter(buzzer->timer, 0);
	timer_enable_preload(buzzer->timer);
	timer_enable_break_main_output(buzzer->timer);
	timer_continuous_mode(buzzer->timer);

	timer_disable_oc_output(buzzer->timer, buzzer->channel);
	timer_set_oc_mode(buzzer->timer, buzzer->channel, TIM_OCM_PWM1);
	timer_set_oc_value(buzzer->timer, buzzer->channel, 0);
	timer_enable_oc_output(buzzer->timer, buzzer->channel);
}

void buzzer_enable(struct buzzer *buzzer)
{
	timer_enable_counter(buzzer->timer);
}

void buzzer_disable(struct buzzer *buzzer)
{
	timer_disable_counter(buzzer->timer);
}

void buzzer_set_freq(struct buzzer *buzzer, uint32_t freq)
{
	uint32_t period = 1000000 / freq;

	timer_set_period(buzzer->timer, period);
	timer_set_oc_value(buzzer->timer, buzzer->channel, period / 2);
}