/****************************************************************************
* drivers/audio/tone.c
*
* Copyright (C) 2016 Gregory Nutt. All rights reserved.
* Author: Alan Carvalho de Assis <acassis@gmail.com>
*
* This driver is based on Tone Alarm driver from PX4 project. It was
* modified to become a NuttX driver and to use the Oneshot Timer API.
*
* The PX4 driver is here:
* https://github.com/PX4/Firmware/blob/master/src/drivers/stm32/tone_alarm/tone_alarm.cpp
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <stdint.h>
#include <stdlib.h>
#include <stdbool.h>
#include <stdlib.h>
#include <ctype.h>
#include <unistd.h>
#include <string.h>
#include <semaphore.h>
#include <fcntl.h>
#include <assert.h>
#include <errno.h>
#include <debug.h>
#include <nuttx/kmalloc.h>
#include <nuttx/fs/fs.h>
#include <nuttx/arch.h>
#include <nuttx/drivers/pwm.h>
#include <nuttx/timers/oneshot.h>
#include <nuttx/audio/tone.h>
#include <arch/irq.h>
#ifdef CONFIG_AUDIO_TONE
/****************************************************************************
* Pre-processor Definitions
****************************************************************************/
/* Define tone modes */
#define MODE_NORMAL 1
#define MODE_LEGATO 2
#define MODE_STACCATO 3
/* Max tune string length*/
#define MAX_TUNE_LEN (1 * 256)
/****************************************************************************
* Private Types
****************************************************************************/
/* This structure describes the state of the upper half driver */
struct tone_upperhalf_s
{
uint8_t crefs; /* The number of times the device has been
* opened */
#ifdef CONFIG_PWM_MULTICHAN
uint8_t channel; /* Output channel that drives the tone. */
#endif
volatile bool started; /* True: pulsed output is being generated */
sem_t exclsem; /* Supports mutual exclusion */
struct pwm_info_s tone; /* Pulsed output for Audio Tone */
struct pwm_lowerhalf_s *devtone;
struct oneshot_lowerhalf_s *oneshot;
};
/****************************************************************************
* Private Data
****************************************************************************/
/* Buffer to store the tune */
static char tune_buf[MAX_TUNE_LEN];
/* Semitone offsets from C for the characters 'A'-'G' */
static const uint8_t g_note_tab[] = { 9, 11, 0, 2, 4, 5, 7 };
/* Notes in Frequency */
static const uint16_t g_notes_freq[84] =
{
0x0041, 0x0045, 0x0049, 0x004d, 0x0052, 0x0057, 0x005c,
0x0061, 0x0067, 0x006e, 0x0074, 0x007b, 0x0082, 0x008a,
0x0092, 0x009b, 0x00a4, 0x00ae, 0x00b8, 0x00c3, 0x00cf,
0x00dc, 0x00e9, 0x00f6, 0x0105, 0x0115, 0x0125, 0x0137,
0x0149, 0x015d, 0x0171, 0x0187, 0x019f, 0x01b8, 0x01d2,
0x01ed, 0x020b, 0x022a, 0x024b, 0x026e, 0x0293, 0x02ba,
0x02e3, 0x030f, 0x033e, 0x0370, 0x03a4, 0x03db, 0x0416,
0x0454, 0x0496, 0x04dc, 0x0526, 0x0574, 0x05c7, 0x061f,
0x067d, 0x06e0, 0x0748, 0x07b7, 0x082d, 0x08a9, 0x092d,
0x09b9, 0x0a4d, 0x0ae9, 0x0b8f, 0x0c3f, 0x0cfa, 0x0dc0,
0x0e91, 0x0f6f, 0x105a, 0x1152, 0x125a, 0x1372, 0x149a,
0x15d3, 0x171f, 0x187f, 0x19f4, 0x1b80, 0x1d22, 0x1ede
};
/* Global variable used by the tone generator */
static const char *g_tune;
static const char *g_next;
static uint8_t g_tempo;
static uint8_t g_note_mode;
static uint32_t g_note_length;
static uint32_t g_silence_length;
static uint8_t g_octave;
static bool g_repeat;
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
static void oneshot_callback(FAR struct oneshot_lowerhalf_s *lower,
FAR void *arg);
static uint32_t note_duration(FAR uint32_t *silence, uint32_t note_length,
uint32_t dots);
static uint32_t rest_duration(uint32_t rest_length, uint32_t dots);
static void start_note(FAR struct tone_upperhalf_s *upper, uint8_t note);
static void stop_note(FAR struct tone_upperhalf_s *upper);
static void start_tune(FAR struct tone_upperhalf_s *upper, const char *tune);
static void next_note(FAR struct tone_upperhalf_s *upper);
static int next_char(void);
static uint8_t next_number(void);
static uint8_t next_dots(void);
static int tone_open(FAR struct file *filep);
static int tone_close(FAR struct file *filep);
static ssize_t tone_read(FAR struct file *filep, FAR char *buffer,
size_t buflen);
static ssize_t tone_write(FAR struct file *filep, FAR const char *buffer,
size_t buflen);
/****************************************************************************
* Private Data
****************************************************************************/
static const struct file_operations g_toneops =
{
tone_open, /* open */
tone_close, /* close */
tone_read, /* read */
tone_write, /* write */
0, /* seek */
0 /* ioctl */
#ifndef CONFIG_DISABLE_POLL
, 0 /* poll */
#endif
#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
, 0 /* unlink */
#endif
};
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: oneshot_callback
****************************************************************************/
static void oneshot_callback(FAR struct oneshot_lowerhalf_s *lower,
FAR void *arg)
{
FAR struct tone_upperhalf_s *upper = (FAR struct tone_upperhalf_s *)arg;
audinfo("Oneshot timer expired!\n");
/* Play the next note */
next_note(upper);
}
/****************************************************************************
* Name: note_duration
*
* Description:
* This function calculates the duration in microseconds of play and
* silence for a note given the current tempo, length and mode and the
* number of dots following in the play string.
*
****************************************************************************/
static uint32_t note_duration(FAR uint32_t *silence, uint32_t note_length,
uint32_t dots)
{
uint32_t whole_note_period = (60 * 1000000 * 4) / g_tempo;
uint32_t note_period;
uint32_t dot_extension;
if (note_length == 0)
{
note_length = 1;
}
note_period = whole_note_period / note_length;
switch (g_note_mode)
{
case MODE_NORMAL:
*silence = note_period / 8;
break;
case MODE_STACCATO:
*silence = note_period / 4;
break;
case MODE_LEGATO:
*silence = 0;
break;
default:
auderr("Mode undefined!\n");
break;
}
note_period -= *silence;
dot_extension = note_period / 2;
while (dots--)
{
note_period += dot_extension;
dot_extension /= 2;
}
return note_period;
}
/****************************************************************************
* Name: rest_duration
*
* Description:
* This function calculates the duration in microseconds of a rest
* corresponding to a given note length.
*
****************************************************************************/
static uint32_t rest_duration(uint32_t rest_length, uint32_t dots)
{
uint32_t whole_note_period = (60 * 1000000 * 4) / g_tempo;
uint32_t rest_period;
uint32_t dot_extension;
if (rest_length == 0)
{
rest_length = 1;
}
rest_period = whole_note_period / rest_length;
dot_extension = rest_period / 2;
while (dots--)
{
rest_period += dot_extension;
dot_extension /= 2;
}
return rest_period;
}
/****************************************************************************
* Name: start_note
****************************************************************************/
static void start_note(FAR struct tone_upperhalf_s *upper, uint8_t note)
{
FAR struct pwm_lowerhalf_s *tone = upper->devtone;
upper->tone.frequency = g_notes_freq[note - 1];
#ifdef CONFIG_PWM_MULTICHAN
upper->tone.channels[0].channel = upper->channel;
upper->tone.channels[0].duty = b16HALF;
#else
upper->tone.duty = b16HALF;
#endif
/* REVISIT: Should check the return value */
tone->ops->start(tone, &upper->tone);
}
/****************************************************************************
* Name: stop_note
****************************************************************************/
static void stop_note(FAR struct tone_upperhalf_s *upper)
{
FAR struct pwm_lowerhalf_s *tone = upper->devtone;
tone->ops->stop(tone);
}
/****************************************************************************
* Name: start_tune
*
* Description:
* This function starts playing the note.
*
****************************************************************************/
static void start_tune(FAR struct tone_upperhalf_s *upper, const char *tune)
{
FAR struct timespec ts;
/* Kill any current playback */
ONESHOT_CANCEL(upper->oneshot, &ts);
/* Record the tune */
g_tune = tune;
g_next = tune;
/* Initialise player state */
g_tempo = 120;
g_note_length = 4;
g_note_mode = MODE_NORMAL;
g_octave = 4;
g_silence_length = 0;
g_repeat = false;
/* Schedule a callback to start playing */
ts.tv_sec = 1;
ts.tv_nsec = 0;
ONESHOT_START(upper->oneshot, oneshot_callback, upper, &ts);
}
/****************************************************************************
* Name: next_note
*
* Description:
* This function parses the next note out of the string and play it.
*
****************************************************************************/
static void next_note(FAR struct tone_upperhalf_s *upper)
{
uint32_t note;
uint32_t note_length;
uint32_t duration;
uint32_t sec;
uint32_t nsec;
FAR struct timespec ts;
/* Do we have an inter-note gap to wait for? */
if (g_silence_length > 0)
{
stop_note(upper);
duration = g_silence_length;
/* Setup the time duration */
sec = duration / USEC_PER_SEC;
nsec = ((duration) - (sec * USEC_PER_SEC)) * NSEC_PER_USEC;
ts.tv_sec = (time_t) sec;
ts.tv_nsec = (unsigned long)nsec;
ONESHOT_START(upper->oneshot, oneshot_callback, upper, &ts);
g_silence_length = 0;
return;
}
/* Make sure we still have a tune - may be removed by the write / ioctl
* handler */
if ((g_next == NULL) || (g_tune == NULL))
{
stop_note(upper);
return;
}
/* Parse characters out of the string until we have resolved a note */
note = 0;
note_length = g_note_length;
while (note == 0)
{
/* We always need at least one character from the string */
int c = next_char();
if (c == 0)
{
goto tune_end;
}
g_next++;
switch (c)
{
uint8_t nt;
/* Select note length */
case 'L':
g_note_length = next_number();
if (g_note_length < 1)
{
auderr("note length too short!\n");
goto tune_error;
}
break;
/* Select octave */
case 'O':
g_octave = next_number();
if (g_octave > 6)
{
g_octave = 6;
}
break;
/* Decrease octave */
case '<':
if (g_octave > 0)
{
g_octave--;
}
break;
/* Increase octave */
case '>':
if (g_octave < 6)
{
g_octave++;
}
break;
/* Select inter-note gap */
case 'M':
c = next_char();
if (c == 0)
{
auderr("no character after M!\n");
goto tune_error;
}
g_next++;
switch (c)
{
case 'N':
g_note_mode = MODE_NORMAL;
break;
case 'L':
g_note_mode = MODE_LEGATO;
break;
case 'S':
g_note_mode = MODE_STACCATO;
break;
case 'F':
g_repeat = false;
break;
case 'B':
g_repeat = true;
break;
default:
auderr("unknown symbol: %c!\n", c);
goto tune_error;
break;
}
/* Pause for a note length */
case 'P':
stop_note(upper);
duration = rest_duration(next_number(), next_dots());
/* Setup the time duration */
sec = duration / USEC_PER_SEC;
nsec = ((duration) - (sec * USEC_PER_SEC)) * NSEC_PER_USEC;
ts.tv_sec = (time_t) sec;
ts.tv_nsec = (unsigned long)nsec;
ONESHOT_START(upper->oneshot, oneshot_callback, upper, &ts);
return;
/* Change tempo */
case 'T':
nt = next_number();
if ((nt >= 32) && (nt <= 255))
{
g_tempo = nt;
}
else
{
auderr("T is out of range 32-255!\n");
goto tune_error;
}
break;
/* Play an arbitrary note */
case 'N':
note = next_number();
if (note > 84)
{
auderr("Note higher than 84!\n");
goto tune_error;
}
/* This is a rest - pause for the current note length */
if (note == 0)
{
duration = rest_duration(g_note_length, next_dots());
/* Setup the time duration */
sec = duration / USEC_PER_SEC;
nsec = ((duration) - (sec * USEC_PER_SEC)) * NSEC_PER_USEC;
ts.tv_sec = (time_t) sec;
ts.tv_nsec = (unsigned long)nsec;
ONESHOT_START(upper->oneshot, oneshot_callback, upper, &ts);
return;
}
break;
/* Play a note in the current octave */
case 'A':
case 'B':
case 'C':
case 'D':
case 'E':
case 'F':
case 'G':
note = g_note_tab[c - 'A'] + (g_octave * 12) + 1;
c = next_char();
switch (c)
{
/* Up a semitone */
case '#':
case '+':
if (note < 84)
{
note++;
}
g_next++;
break;
/* Down a semitone */
case '-':
if (note > 1)
{
note--;
}
g_next++;
break;
/* No next char here is OK */
default:
break;
}
/* Shorthand length notation */
note_length = next_number();
if (note_length == 0)
{
note_length = g_note_length;
}
break;
default:
goto tune_error;
}
}
/* Compute the duration of the note and the following silence (if any) */
duration = note_duration(&g_silence_length, note_length, next_dots());
/* Start playing the note */
start_note(upper, note);
/* Setup time duration */
sec = duration / USEC_PER_SEC;
nsec = ((duration) - (sec * USEC_PER_SEC)) * NSEC_PER_USEC;
ts.tv_sec = (time_t) sec;
ts.tv_nsec = (unsigned long)nsec;
/* And arrange a callback when the note should stop */
ONESHOT_START(upper->oneshot, oneshot_callback, upper, &ts);
return;
/* Tune looks bad (unexpected EOF, bad character, etc.) */
tune_error:
auderr("tune error\n");
/* Don't loop on error */
g_repeat = false;
/* Stop (and potentially restart) the tune */
tune_end:
stop_note(upper);
if (g_repeat)
{
start_tune(upper, g_tune);
}
else
{
g_tune = NULL;
}
}
/****************************************************************************
* Name: next_char
*
* Description:
* This function find the next character in the string, discard any
* whitespace and return the canonical (uppercase) version.
*
****************************************************************************/
static int next_char(void)
{
while (isspace(*g_next))
{
g_next++;
}
return toupper(*g_next);
}
/****************************************************************************
* Name: next_number
*
* Description:
* This function extract a number from the string, consuming all the digit
* characters.
*
****************************************************************************/
static uint8_t next_number(void)
{
uint8_t number = 0;
int c;
for (;;)
{
c = next_char();
if (!isdigit(c))
{
return number;
}
g_next++;
number = (number * 10) + (c - '0');
}
return number;
}
/****************************************************************************
* Name: next_dots
*
* Description:
* This function consumes dot characters from the string, returning the
* number consumed.
*
****************************************************************************/
static uint8_t next_dots(void)
{
uint8_t dots = 0;
while (next_char() == '.')
{
g_next++;
dots++;
}
return dots;
}
/****************************************************************************
* Name: tone_open
*
* Description:
* This function is called whenever the PWM device is opened.
*
****************************************************************************/
static int tone_open(FAR struct file *filep)
{
FAR struct inode *inode = filep->f_inode;
FAR struct tone_upperhalf_s *upper = inode->i_private;
uint8_t tmp;
int ret;
audinfo("crefs: %d\n", upper->crefs);
/* Get exclusive access to the device structures */
ret = sem_wait(&upper->exclsem);
if (ret < 0)
{
ret = -get_errno();
goto errout;
}
/* Increment the count of references to the device. If this the first time
* that the driver has been opened for this device, then initialize the
* device. */
tmp = upper->crefs + 1;
if (tmp == 0)
{
/* More than 255 opens; uint8_t overflows to zero */
ret = -EMFILE;
goto errout_with_sem;
}
/* Save the new open count on success */
upper->crefs = tmp;
ret = OK;
errout_with_sem:
sem_post(&upper->exclsem);
errout:
return ret;
}
/****************************************************************************
* Name: tone_close
*
* Description:
* This function is called when the PWM device is closed.
*
****************************************************************************/
static int tone_close(FAR struct file *filep)
{
FAR struct inode *inode = filep->f_inode;
FAR struct tone_upperhalf_s *upper = inode->i_private;
int ret;
audinfo("crefs: %d\n", upper->crefs);
/* Get exclusive access to the device structures */
ret = sem_wait(&upper->exclsem);
if (ret < 0)
{
ret = -get_errno();
goto errout;
}
/* Decrement the references to the driver. If the reference count will
* decrement to 0, then uninitialize the driver. */
if (upper->crefs > 1)
{
upper->crefs--;
}
sem_post(&upper->exclsem);
ret = OK;
errout:
return ret;
}
/****************************************************************************
* Name: tone_read
*
* Description:
* A dummy read method. This is provided only to satisfy the VFS layer.
*
****************************************************************************/
static ssize_t tone_read(FAR struct file *filep, FAR char *buffer,
size_t buflen)
{
/* Return zero -- usually meaning end-of-file */
return 0;
}
/****************************************************************************
* Name: tone_write
*
* Description:
* A dummy write method. This is provided only to satisfy the VFS layer.
*
****************************************************************************/
static ssize_t tone_write(FAR struct file *filep, FAR const char *buffer,
size_t buflen)
{
FAR struct inode *inode = filep->f_inode;
FAR struct tone_upperhalf_s *upper = inode->i_private;
/* We need to receive a string #RRGGBB = 7 bytes */
if (buffer == NULL)
{
/* Well... nothing to do */
return -EINVAL;
}
if (buflen >= MAX_TUNE_LEN)
{
/* Too big to it inside internal buffer (with extra NUL terminator) */
return -EINVAL;
}
/* Copy music to internal buffer */
memcpy(tune_buf, buffer, buflen);
/* Failsafe NUL terminated string */
tune_buf[buflen] = '\0';
/* Let the music play */
start_tune(upper, tune_buf);
return buflen;
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: tone_register
*
* Description:
* This function binds an instance of a "lower half" PWM driver with
* the "upper half" Audio Tone device and registers that device so that can
* be used by application code.
*
*
* Input parameters:
* path - The full path to the driver to be registers in the NuttX pseudo-
* filesystem. The recommended convention is to name of PWM driver
* as "/dev/tone0".
* tone - A pointer to an instance of lower half PWM
* drivers for the tone device. This instance will be bound to the Audio
* tone driver and must persists as long as that driver persists.
*
* Returned Value:
* Zero on success; a negated errno value on failure.
*
****************************************************************************/
int tone_register(FAR const char *path, FAR struct pwm_lowerhalf_s *tone,
#ifdef CONFIG_PWM_MULTICHAN
int channel,
#endif
FAR struct oneshot_lowerhalf_s *oneshot)
{
FAR struct tone_upperhalf_s *upper;
DEBUGASSERT(path != NULL && tone != NULL);
/* Allocate the upper-half data structure */
upper =
(FAR struct tone_upperhalf_s *)kmm_zalloc(sizeof(struct tone_upperhalf_s));
if (!upper)
{
auderr("ERROR: Allocation failed\n");
return -ENOMEM;
}
/* Initialize the PWM device structure (it was already zeroed by
* kmm_zalloc()).
*/
sem_init(&upper->exclsem, 0, 1);
upper->devtone = tone;
upper->oneshot = oneshot;
#ifdef CONFIG_PWM_MULTICHAN
upper->channel = (uint8_t)channel;
#endif
/* Register the PWM device */
audinfo("Registering %s\n", path);
return register_driver(path, &g_toneops, 0666, upper);
}
#endif /* CONFIG_AUDIO_TONE */