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dm: sound: Use the correct number of channels for sound 

At present the 'beep' sound generates a waveform for only one channel even
if two are being used. This means that the beep is twice the frequency it
should be. Correct this by making it a parameter.

The fix in a previous commit was correct for sandbox but not for other
boards.

Fixes: 03f11e87a8 ("sound: Correct data output in sound_create_square_wave()")
Signed-off-by: Simon Glass <sjg@chromium.org>
This commit is contained in:
Simon Glass 2018-12-10 10:37:51 -07:00
parent e221cdcf44
commit f987177db9
3 changed files with 14 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/sound/sound-uclass.c
View File

@ -53,7 +53,7 @@ int sound_beep(struct udevice *dev, int msecs, int frequency_hz)
} }
sound_create_square_wave(i2s_uc_priv->samplingrate, data, data_size, sound_create_square_wave(i2s_uc_priv->samplingrate, data, data_size,
frequency_hz); frequency_hz, i2s_uc_priv->channels);
while (msecs >= 1000) { while (msecs >= 1000) {
ret = sound_play(dev, data, data_size); ret = sound_play(dev, data, data_size);

11
drivers/sound/sound.c
View File

@ -8,7 +8,7 @@
#include <sound.h> #include <sound.h>
void sound_create_square_wave(uint sample_rate, unsigned short *data, int size, void sound_create_square_wave(uint sample_rate, unsigned short *data, int size,
uint freq) uint freq, uint channels)
{ {
const unsigned short amplitude = 16000; /* between 1 and 32767 */ const unsigned short amplitude = 16000; /* between 1 and 32767 */
const int period = freq ? sample_rate / freq : 0; const int period = freq ? sample_rate / freq : 0;
@ -21,14 +21,17 @@ void sound_create_square_wave(uint sample_rate, unsigned short *data, int size,
size--; size--;
while (size) { while (size) {
int i; int i, j;
for (i = 0; size && i < half; i++) { for (i = 0; size && i < half; i++) {
size -= 2; size -= 2;
*data++ = amplitude; for (j = 0; j < channels; j++)
*data++ = amplitude;
} }
for (i = 0; size && i < period - half; i++) { for (i = 0; size && i < period - half; i++) {
size -= 2; size -= 2;
*data++ = -amplitude; for (j = 0; j < channels; j++)
*data++ = -amplitude;
} }
} }
} }

11
include/sound.h
View File

@ -37,13 +37,14 @@ struct sound_uc_priv {
/** /**
* Generates square wave sound data for 1 second * Generates square wave sound data for 1 second
* *
* @param sample_rate Sample rate in Hz * @sample_rate: Sample rate in Hz
* @param data data buffer pointer * @data: data buffer pointer
* @param size size of the buffer in bytes * @size: size of the buffer in bytes
* @param freq frequency of the wave * @freq: frequency of the wave
* @channels: Number of channels to use
*/ */
void sound_create_square_wave(uint sample_rate, unsigned short *data, int size, void sound_create_square_wave(uint sample_rate, unsigned short *data, int size,
uint freq); uint freq, uint channels);
/* /*
* The sound uclass brings together a data transport (currently only I2C) and a * The sound uclass brings together a data transport (currently only I2C) and a