pwm_dac.c File Reference

#include <stddef.h>
#include "compiler.h"
#include "pwm_dac.h"
#include <avr32/io.h>
#include "intc.h"
#include "gpio.h"
#include "audio.h"

Macros
#define	PWM_DAC_PWM_CHANNEL_LSB   6
	Least significant 8-bit PWM channel. More...
#define	PWM_DAC_PWM_CHANNEL_LSB_PIN   _0
	Least significant 8-bit PWM channel pin. More...
#define	PWM_DAC_PWM_CHANNEL_MSB   4
	Most significant 8-bit PWM channel. More...
#define	PWM_DAC_PWM_CHANNEL_MSB_PIN   _1
	Most significant 8-bit PWM channel pin. More...

Functions
void	pwm_dac_decrease_volume (void)
	Decreases the output volume of the DAC. More...
void	pwm_dac_flush (void)
	Flushes the sample buffer being output to the DAC. More...
static __inline__ size_t	pwm_dac_get_log2_aligned_byte_size (size_t bit_size)
	Returns the logarithm to base 2 of the aligned byte size required to store the bit_size bit size saturated to the range [|8, 32|]. More...
static int16_t	pwm_dac_get_sample_16_bits (void)
	Generates a 16-bit sample from a sample stored in 16 bits. More...
static int16_t	pwm_dac_get_sample_32_bits (void)
	Generates a 16-bit sample from a sample stored in 32 bits. More...
static int16_t	pwm_dac_get_sample_8_bits (void)
	Generates a 16-bit sample from a sample stored in 8 bits. More...
uint8_t	pwm_dac_get_volume (void)
	Return the current volume. More...
void	pwm_dac_increase_volume (void)
	Increases the output volume of the DAC. More...
bool	pwm_dac_is_volume_boosted (void)
	Returns the state of the boost mode of the DAC. More...
bool	pwm_dac_is_volume_muted (void)
	Returns the state of the mute mode of the DAC. More...
void	pwm_dac_mute (bool mute)
	Mute audio if mute set to true. More...
bool	pwm_dac_output (void *sample_buffer, size_t sample_length)
	Outputs a sample buffer to the DAC. More...
static __inline__ void	pwm_dac_output_sample (int16_t sample)
	Outputs a sample to the DAC. More...
static void	pwm_dac_pwm_int_handler (void)
	PWM interrupt handler managing the DAC. More...
void	pwm_dac_set_volume (uint8_t volume)
	Set the current volume. More...
void	pwm_dac_setup (uint32_t sample_rate_hz, uint8_t num_channels, uint8_t bits_per_sample, bool swap_channels, void(*callback)(uint32_t arg), uint32_t callback_opt, uint32_t pba_hz)
	Sets the DAC up with new settings. More...
void	pwm_dac_start (uint32_t sample_rate_hz, uint8_t num_channels, uint8_t bits_per_sample, bool swap_channels, void(*callback)(uint32_t arg), uint32_t callback_opt, uint32_t pba_hz)
	Starts the DAC. More...
void	pwm_dac_stop (void)
	Stops the DAC. More...

Variables
static int16_t(*const	PWM_DAC_GET_SAMPLE [])(void)
	Table of pointers to the functions generating 16-bit samples from stored samples. More...
struct {
uint8_t   bits_per_sample
void(*   callback )(uint32_t arg)
uint32_t   callback_opt
bool   flushing
int16_t(*   get_sample )(void)
uint8_t   num_channels
volatile UnionPtr   reload_sample_buffer
volatile size_t   reload_sample_length
volatile UnionPtr   sample_buffer
volatile size_t   sample_length
bool   swap_channels
uint8_t   volume_shift
}	pwm_dac_output_params
	Output parameters. More...
static const gpio_map_t	PWM_DAC_PWM_GPIO_MAP
	Map of the PWM pins used by the PWM DAC. More...

#define PWM_DAC_PWM_CHANNEL_LSB   6

Least significant 8-bit PWM channel.

Referenced by pwm_dac_flush(), pwm_dac_output(), pwm_dac_output_sample(), pwm_dac_pwm_int_handler(), pwm_dac_start(), and pwm_dac_stop().

#define PWM_DAC_PWM_CHANNEL_LSB_PIN   _0

Least significant 8-bit PWM channel pin.

#define PWM_DAC_PWM_CHANNEL_MSB   4

Most significant 8-bit PWM channel.

Referenced by pwm_dac_flush(), pwm_dac_output(), pwm_dac_output_sample(), pwm_dac_pwm_int_handler(), pwm_dac_start(), and pwm_dac_stop().

#define PWM_DAC_PWM_CHANNEL_MSB_PIN   _1

Most significant 8-bit PWM channel pin.

static __inline__ size_t pwm_dac_get_log2_aligned_byte_size ( size_t  bit_size )

static

Returns the logarithm to base 2 of the aligned byte size required to store the bit_size bit size saturated to the range [|8, 32|].

References clz, max, and min.

Referenced by pwm_dac_output(), and pwm_dac_setup().

static int16_t pwm_dac_get_sample_16_bits ( void  )

static

Generates a 16-bit sample from a sample stored in 16 bits.

References pwm_dac_output_params.

static int16_t pwm_dac_get_sample_32_bits ( void  )

static

Generates a 16-bit sample from a sample stored in 32 bits.

References pwm_dac_output_params.

static int16_t pwm_dac_get_sample_8_bits ( void  )

static

Generates a 16-bit sample from a sample stored in 8 bits.

References pwm_dac_output_params.

static __inline__ void pwm_dac_output_sample ( int16_t  sample )

static

Outputs a sample to the DAC.

References PWM_DAC_PWM_CHANNEL_LSB, and PWM_DAC_PWM_CHANNEL_MSB.

Referenced by pwm_dac_flush(), pwm_dac_pwm_int_handler(), and pwm_dac_start().

static void pwm_dac_pwm_int_handler ( void  )

static

PWM interrupt handler managing the DAC.

References AUDIO_DAC_OUT_OF_SAMPLE_CB, AUDIO_DAC_RELOAD_CB, NULL, pwm_dac_output_params, pwm_dac_output_sample(), PWM_DAC_PWM_CHANNEL_LSB, and PWM_DAC_PWM_CHANNEL_MSB.

Referenced by pwm_dac_start().

uint8_t bits_per_sample

Referenced by audio_mixer_dacs_setup_direct(), audio_mixer_dacs_start_direct(), pwm_dac_setup(), and usb_stream_init().

void(* callback)(uint32_t arg)

uint32_t callback_opt

bool flushing

int16_t(* get_sample)(void)

Referenced by dac_pwm_int_handler(), and main().

uint8_t num_channels

int16_t(*const PWM_DAC_GET_SAMPLE[])(void)

static

Initial value:

=
{
  pwm_dac_get_sample_8_bits,
  pwm_dac_get_sample_16_bits,
  pwm_dac_get_sample_32_bits
}

Table of pointers to the functions generating 16-bit samples from stored samples.

Referenced by pwm_dac_setup().

struct { ... } pwm_dac_output_params

Initial value:

=
{
  .num_channels             = 0,
  .bits_per_sample          = 0,
  .swap_channels            = false,
  .callback                 = NULL,
  .callback_opt             = 0,
  .get_sample               = NULL,
  .sample_buffer            = {NULL},
  .sample_length            = 0,
  .reload_sample_buffer     = {NULL},
  .reload_sample_length     = 0,
  .volume_shift             = 0,
  .flushing                 = false
}

Output parameters.

Referenced by pwm_dac_decrease_volume(), pwm_dac_flush(), pwm_dac_get_sample_16_bits(), pwm_dac_get_sample_32_bits(), pwm_dac_get_sample_8_bits(), pwm_dac_get_volume(), pwm_dac_increase_volume(), pwm_dac_output(), pwm_dac_pwm_int_handler(), pwm_dac_set_volume(), pwm_dac_setup(), and pwm_dac_stop().

const gpio_map_t PWM_DAC_PWM_GPIO_MAP

static

Initial value:

=
{
  {ATPASTE4(AVR32_PWM_, PWM_DAC_PWM_CHANNEL_LSB, PWM_DAC_PWM_CHANNEL_LSB_PIN, _PIN),
   ATPASTE4(AVR32_PWM_, PWM_DAC_PWM_CHANNEL_LSB, PWM_DAC_PWM_CHANNEL_LSB_PIN, _FUNCTION)},
  {ATPASTE4(AVR32_PWM_, PWM_DAC_PWM_CHANNEL_MSB, PWM_DAC_PWM_CHANNEL_MSB_PIN, _PIN),
   ATPASTE4(AVR32_PWM_, PWM_DAC_PWM_CHANNEL_MSB, PWM_DAC_PWM_CHANNEL_MSB_PIN, _FUNCTION)}
}

Map of the PWM pins used by the PWM DAC.

volatile UnionPtr reload_sample_buffer

volatile size_t reload_sample_length

volatile UnionPtr sample_buffer

Referenced by aic23b_dac_output(), buff_player_malloc(), buff_player_put_pcm_buf(), ms3_dac_output(), and pwm_dac_output().

volatile size_t sample_length

Referenced by buff_player_malloc(), buff_player_put_pcm_buf(), and pwm_dac_output().

bool swap_channels

Referenced by aic23b_dac_setup(), audio_mixer_dacs_setup_direct(), audio_mixer_dacs_start_direct(), pwm_dac_setup(), and usb_stream_init().

uint8_t volume_shift