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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/u-boot/drivers/sound/sound.c
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/u-boot/drivers/sound/sound.c')
-rw-r--r--qemu/roms/u-boot/drivers/sound/sound.c37
1 files changed, 37 insertions, 0 deletions
diff --git a/qemu/roms/u-boot/drivers/sound/sound.c b/qemu/roms/u-boot/drivers/sound/sound.c
new file mode 100644
index 000000000..9dda2dba8
--- /dev/null
+++ b/qemu/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;
+ }
+ }
+}