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// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2012 Samsung Electronics
* R. Chandrasekar <rcsekar@samsung.com>
*/
#include <log.h>
#include <sound.h>
#include <linux/string.h>
void sound_create_square_wave(uint sample_rate, unsigned short *data, int size,
uint freq, uint channels)
{
const unsigned short amplitude = 16000; /* between 1 and 32767 */
const int period = freq ? sample_rate / freq : 0;
const int half = period / 2;
if (!half) {
memset(data, 0, size);
return;
}
/* Make sure we don't overflow our buffer */
if (size % 2)
size--;
while (size) {
int i, j;
for (i = 0; size && i < half; i++) {
for (j = 0; size && j < channels; j++, size -= 2)
*data++ = amplitude;
}
for (i = 0; size && i < period - half; i++) {
for (j = 0; size && j < channels; j++, size -= 2)
*data++ = -amplitude;
}
}
}
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