959 lines
23 KiB
C
959 lines
23 KiB
C
/****************************************************************************
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* drivers/audio/tone.c
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*
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* Copyright (C) 2016 Gregory Nutt. All rights reserved.
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* Author: Alan Carvalho de Assis <acassis@gmail.com>
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*
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* This driver is based on Tone Alarm driver from PX4 project. It was
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* modified to become a NuttX driver and to use the Oneshot Timer API.
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*
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* The PX4 driver is here:
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* https://github.com/PX4/Firmware/blob/master/src/drivers/stm32/tone_alarm/tone_alarm.cpp
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in
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* the documentation and/or other materials provided with the
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* distribution.
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* 3. Neither the name NuttX nor the names of its contributors may be
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* used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
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* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.
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*
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****************************************************************************/
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <nuttx/config.h>
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#include <sys/types.h>
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#include <stdint.h>
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#include <stdlib.h>
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#include <stdbool.h>
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#include <stdlib.h>
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#include <ctype.h>
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#include <unistd.h>
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#include <string.h>
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#include <semaphore.h>
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#include <math.h>
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#include <fcntl.h>
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#include <assert.h>
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#include <errno.h>
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#include <debug.h>
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#include <nuttx/kmalloc.h>
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#include <nuttx/fs/fs.h>
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#include <nuttx/arch.h>
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#include <nuttx/drivers/pwm.h>
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#include <nuttx/timers/oneshot.h>
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#include <nuttx/audio/tone.h>
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#include <arch/irq.h>
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#ifdef CONFIG_AUDIO_TONE
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/****************************************************************************
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* Pre-processor Definitions
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****************************************************************************/
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/* Define tone modes */
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#define MODE_NORMAL 1
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#define MODE_LEGATO 2
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#define MODE_STACCATO 3
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/* Max tune string length*/
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#define MAX_TUNE_LEN (1 * 256)
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/****************************************************************************
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* Private Types
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****************************************************************************/
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/* This structure describes the state of the upper half driver */
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struct tone_upperhalf_s
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{
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uint8_t crefs; /* The number of times the device has been
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* opened */
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volatile bool started; /* True: pulsed output is being generated */
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sem_t exclsem; /* Supports mutual exclusion */
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struct pwm_info_s tone; /* Pulsed output for Audio Tone */
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struct pwm_lowerhalf_s *devtone;
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struct oneshot_lowerhalf_s *oneshot;
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};
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/****************************************************************************
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* Private Data
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****************************************************************************/
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/* Buffer to store the tune */
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static char tune_buf[MAX_TUNE_LEN];
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/* Semitone offsets from C for the characters 'A'-'G' */
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static const uint8_t g_note_tab[] = { 9, 11, 0, 2, 4, 5, 7 };
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/* Global variable used by the tone generator */
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static const char *g_tune;
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static const char *g_next;
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static uint8_t g_tempo;
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static uint8_t g_note_mode;
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static uint32_t g_note_length;
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static uint32_t g_silence_length;
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static uint8_t g_octave;
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static bool g_repeat;
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/****************************************************************************
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* Private Function Prototypes
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****************************************************************************/
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static int tone_open(FAR struct file *filep);
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static int tone_close(FAR struct file *filep);
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static ssize_t tone_read(FAR struct file *filep, FAR char *buffer,
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size_t buflen);
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static ssize_t tone_write(FAR struct file *filep, FAR const char *buffer,
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size_t buflen);
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static int next_char(void);
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static uint8_t next_number(void);
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static uint8_t next_dots(void);
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static void next_note(FAR struct tone_upperhalf_s *upper);
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/****************************************************************************
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* Private Data
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****************************************************************************/
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static const struct file_operations g_toneops =
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{
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tone_open, /* open */
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tone_close, /* close */
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tone_read, /* read */
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tone_write, /* write */
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0, /* seek */
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0 /* ioctl */
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#ifndef CONFIG_DISABLE_POLL
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, 0 /* poll */
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#endif
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#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
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, 0 /* unlink */
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#endif
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};
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/****************************************************************************
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* Private Functions
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****************************************************************************/
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/****************************************************************************
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* Name: oneshot_callback
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****************************************************************************/
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static void oneshot_callback(FAR struct oneshot_lowerhalf_s *lower,
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FAR void *arg)
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{
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FAR struct tone_upperhalf_s *upper = (FAR struct tone_upperhalf_s *)arg;
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audinfo("Oneshot timer expired!\n");
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/* Play the next note */
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next_note(upper);
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}
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/****************************************************************************
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* Name: note_to_freq
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*
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* Description:
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* This function converts a note value in the range C1 to B7 to frequency.
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*
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****************************************************************************/
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static uint16_t note_to_freq(uint8_t note)
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{
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/* Compute the frequency in Hz */
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uint16_t freq = 880.0f * expf(logf(2.0f) * ((int)note - 46) / 12.0f);
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return freq;
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}
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/****************************************************************************
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* Name: note_duration
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*
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* Description:
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* This function calculates the duration in microseconds of play and
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* silence for a note given the current tempo, length and mode and the
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* number of dots following in the play string.
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*
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****************************************************************************/
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static uint32_t note_duration(FAR uint32_t *silence, uint32_t note_length,
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uint32_t dots)
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{
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uint32_t whole_note_period = (60 * 1000000 * 4) / g_tempo;
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uint32_t note_period;
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uint32_t dot_extension;
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if (note_length == 0)
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{
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note_length = 1;
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}
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note_period = whole_note_period / note_length;
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switch (g_note_mode)
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{
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case MODE_NORMAL:
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*silence = note_period / 8;
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break;
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case MODE_STACCATO:
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*silence = note_period / 4;
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break;
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case MODE_LEGATO:
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*silence = 0;
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break;
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default:
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auderr("Mode undefined!\n");
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break;
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}
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note_period -= *silence;
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dot_extension = note_period / 2;
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while (dots--)
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{
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note_period += dot_extension;
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dot_extension /= 2;
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}
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return note_period;
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}
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/****************************************************************************
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* Name: rest_duration
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*
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* Description:
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* This function calculates the duration in microseconds of a rest
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* corresponding to a given note length.
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*
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****************************************************************************/
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static uint32_t rest_duration(uint32_t rest_length, uint32_t dots)
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{
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uint32_t whole_note_period = (60 * 1000000 * 4) / g_tempo;
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uint32_t rest_period;
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uint32_t dot_extension;
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if (rest_length == 0)
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{
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rest_length = 1;
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}
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rest_period = whole_note_period / rest_length;
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dot_extension = rest_period / 2;
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while (dots--)
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{
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rest_period += dot_extension;
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dot_extension /= 2;
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}
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return rest_period;
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}
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/****************************************************************************
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* Name: start_note
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****************************************************************************/
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static void start_note(FAR struct tone_upperhalf_s *upper, uint8_t note)
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{
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FAR struct pwm_lowerhalf_s *tone = upper->devtone;
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upper->tone.frequency = note_to_freq(note);
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upper->tone.duty = 50;
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tone->ops->start(tone, &upper->tone);
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return;
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}
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/****************************************************************************
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* Name: stop_note
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****************************************************************************/
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static void stop_note(FAR struct tone_upperhalf_s *upper)
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{
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FAR struct pwm_lowerhalf_s *tone = upper->devtone;
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tone->ops->stop(tone);
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return;
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}
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/****************************************************************************
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* Name: start_tune
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*
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* Description:
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* This function starts playing the note.
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*
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****************************************************************************/
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static void start_tune(FAR struct tone_upperhalf_s *upper, const char *tune)
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{
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FAR struct timespec ts;
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/* Kill any current playback */
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ONESHOT_CANCEL(upper->oneshot, &ts);
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/* Record the tune */
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g_tune = tune;
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g_next = tune;
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/* Initialise player state */
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g_tempo = 120;
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g_note_length = 4;
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g_note_mode = MODE_NORMAL;
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g_octave = 4;
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g_silence_length = 0;
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g_repeat = false;
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/* Schedule a callback to start playing */
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ts.tv_sec = 1;
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ts.tv_nsec = 0;
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ONESHOT_START(upper->oneshot, oneshot_callback, upper, &ts);
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}
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/****************************************************************************
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* Name: next_note
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*
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* Description:
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* This function parses the next note out of the string and play it.
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*
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****************************************************************************/
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static void next_note(FAR struct tone_upperhalf_s *upper)
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{
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uint32_t note;
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uint32_t note_length;
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uint32_t duration;
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uint32_t sec;
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uint32_t nsec;
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FAR struct timespec ts;
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/* Do we have an inter-note gap to wait for? */
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if (g_silence_length > 0)
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{
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stop_note(upper);
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duration = g_silence_length;
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/* Setup the time duration */
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sec = duration / USEC_PER_SEC;
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nsec = ((duration) - (sec * USEC_PER_SEC)) * NSEC_PER_USEC;
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ts.tv_sec = (time_t) sec;
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ts.tv_nsec = (unsigned long)nsec;
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ONESHOT_START(upper->oneshot, oneshot_callback, upper, &ts);
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g_silence_length = 0;
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return;
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}
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/* Make sure we still have a tune - may be removed by the write / ioctl
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* handler */
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if ((g_next == NULL) || (g_tune == NULL))
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{
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stop_note(upper);
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return;
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}
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/* Parse characters out of the string until we have resolved a note */
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note = 0;
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note_length = g_note_length;
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while (note == 0)
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{
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/* We always need at least one character from the string */
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int c = next_char();
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if (c == 0)
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{
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goto tune_end;
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}
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g_next++;
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switch (c)
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{
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uint8_t nt;
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/* Select note length */
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case 'L':
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g_note_length = next_number();
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if (g_note_length < 1)
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{
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auderr("note length too short!\n");
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goto tune_error;
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}
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break;
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/* Select octave */
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case 'O':
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g_octave = next_number();
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if (g_octave > 6)
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{
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g_octave = 6;
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}
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break;
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/* Decrease octave */
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case '<':
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if (g_octave > 0)
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{
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g_octave--;
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}
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break;
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/* Increase octave */
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case '>':
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if (g_octave < 6)
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{
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g_octave++;
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}
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break;
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/* Select inter-note gap */
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case 'M':
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c = next_char();
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if (c == 0)
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{
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auderr("no character after M!\n");
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goto tune_error;
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}
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g_next++;
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switch (c)
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{
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case 'N':
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g_note_mode = MODE_NORMAL;
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break;
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case 'L':
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g_note_mode = MODE_LEGATO;
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break;
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case 'S':
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g_note_mode = MODE_STACCATO;
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break;
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case 'F':
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g_repeat = false;
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break;
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case 'B':
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g_repeat = true;
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break;
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default:
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auderr("unknown symbol: %c!\n", c);
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goto tune_error;
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break;
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}
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/* Pause for a note length */
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case 'P':
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stop_note(upper);
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duration = rest_duration(next_number(), next_dots());
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/* Setup the time duration */
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sec = duration / USEC_PER_SEC;
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nsec = ((duration) - (sec * USEC_PER_SEC)) * NSEC_PER_USEC;
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ts.tv_sec = (time_t) sec;
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ts.tv_nsec = (unsigned long)nsec;
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ONESHOT_START(upper->oneshot, oneshot_callback, upper, &ts);
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return;
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/* Change tempo */
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case 'T':
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nt = next_number();
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if ((nt >= 32) && (nt <= 255))
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{
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g_tempo = nt;
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}
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else
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{
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auderr("T is out of range 32-255!\n");
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goto tune_error;
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}
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break;
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/* Play an arbitrary note */
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case 'N':
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note = next_number();
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if (note > 84)
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{
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auderr("Note higher than 84!\n");
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goto tune_error;
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}
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/* This is a rest - pause for the current note length */
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if (note == 0)
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{
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duration = rest_duration(g_note_length, next_dots());
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/* Setup the time duration */
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sec = duration / USEC_PER_SEC;
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nsec = ((duration) - (sec * USEC_PER_SEC)) * NSEC_PER_USEC;
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ts.tv_sec = (time_t) sec;
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ts.tv_nsec = (unsigned long)nsec;
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ONESHOT_START(upper->oneshot, oneshot_callback, upper, &ts);
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return;
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}
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break;
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/* Play a note in the current octave */
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case 'A':
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case 'B':
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case 'C':
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case 'D':
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case 'E':
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case 'F':
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case 'G':
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note = g_note_tab[c - 'A'] + (g_octave * 12) + 1;
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c = next_char();
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switch (c)
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{
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/* Up a semitone */
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case '#':
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case '+':
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if (note < 84)
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{
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note++;
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}
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g_next++;
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break;
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/* Down a semitone */
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case '-':
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if (note > 1)
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{
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note--;
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}
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g_next++;
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break;
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/* No next char here is OK */
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default:
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break;
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}
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/* Shorthand length notation */
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note_length = next_number();
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if (note_length == 0)
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{
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note_length = g_note_length;
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}
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break;
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default:
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goto tune_error;
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}
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}
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|
|
/* 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;
|
|
int ndx;
|
|
|
|
/* 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,
|
|
FAR struct oneshot_lowerhalf_s *oneshot)
|
|
{
|
|
FAR struct tone_upperhalf_s *upper;
|
|
|
|
/* 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;
|
|
|
|
/* Register the PWM device */
|
|
|
|
audinfo("Registering %s\n", path);
|
|
return register_driver(path, &g_toneops, 0666, upper);
|
|
}
|
|
|
|
#endif /* CONFIG_AUDIO_TONE */
|