/*
   * Copyright (C) 2012 Samsung Electronics
   * R. Chandrasekar <rcsekar@samsung.com>
   *
   * SPDX-License-Identifier:	GPL-2.0+
   */
  
  #include <common.h>
  #include <sound.h>
  
  void sound_create_square_wave(unsigned short *data, int size, uint32_t freq)
  {
  	const int sample = 48000;
  	const unsigned short amplitude = 16000; /* between 1 and 32767 */
  	const int period = freq ? sample / freq : 0;
  	const int half = period / 2;
  
  	assert(freq);
  
  	/* Make sure we don't overflow our buffer */
  	if (size % 2)
  		size--;
  
  	while (size) {
  		int i;
  		for (i = 0; size && i < half; i++) {
  			size -= 2;
  			*data++ = amplitude;
  			*data++ = amplitude;
  		}
  		for (i = 0; size && i < period - half; i++) {
  			size -= 2;
  			*data++ = -amplitude;
  			*data++ = -amplitude;
  		}
  	}
  }