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authorfishsoupisgood <github@madingley.org>2019-04-29 01:17:54 +0100
committerfishsoupisgood <github@madingley.org>2019-05-27 03:43:43 +0100
commit3f2546b2ef55b661fd8dd69682b38992225e86f6 (patch)
tree65ca85f13617aee1dce474596800950f266a456c /roms/u-boot/drivers/sound/sound.c
downloadqemu-master.tar.gz
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Initial import of qemu-2.4.1HEADmaster
Diffstat (limited to 'roms/u-boot/drivers/sound/sound.c')
-rw-r--r--roms/u-boot/drivers/sound/sound.c37
1 files changed, 37 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 00000000..9dda2dba
--- /dev/null
+++ b/roms/u-boot/drivers/sound/sound.c
@@ -0,0 +1,37 @@
+/*
+ * 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;
+ }
+ }
+}