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-rw-r--r--roms/u-boot/drivers/sound/sound.c38
1 files changed, 38 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/sound/sound.c b/roms/u-boot/drivers/sound/sound.c
new file mode 100644
index 000000000..b0eab2339
--- /dev/null
+++ b/roms/u-boot/drivers/sound/sound.c
@@ -0,0 +1,38 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2012 Samsung Electronics
+ * R. Chandrasekar <rcsekar@samsung.com>
+ */
+
+#include <common.h>
+#include <log.h>
+#include <sound.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;
+
+ assert(freq);
+
+ /* Make sure we don't overflow our buffer */
+ if (size % 2)
+ size--;
+
+ while (size) {
+ int i, j;
+
+ for (i = 0; size && i < half; i++) {
+ size -= 2;
+ for (j = 0; j < channels; j++)
+ *data++ = amplitude;
+ }
+ for (i = 0; size && i < period - half; i++) {
+ size -= 2;
+ for (j = 0; j < channels; j++)
+ *data++ = -amplitude;
+ }
+ }
+}