alsa_api_test: Add the option to test filling mmap buffer
Test the API to fill whole buffer with zeros. The sequence is:
1. Use snd_pcm_mmap_begin to get the mmap buffer.
2. Fill the mmap buffer with zeros using memset.
3. Do not call snd_pcm_mmap_commit.
4. Let device play for some periods.
5. Use snd_pcm_mmap_begin to get the mmap buffer.
6. Check mmap buffer contains all zeros.
BUG=chromium:601346
TEST=run `alsa_api_test --device hw:1,0 --fill` on samus.
Change-Id: Iea92341f0fe3d1094ea4311198b768bbaaf7cdbf
Reviewed-on: https://chromium-review.googlesource.com/341842
Commit-Ready: Cheng-Yi Chiang <cychiang@chromium.org>
Tested-by: Cheng-Yi Chiang <cychiang@chromium.org>
Reviewed-by: Hsinyu Chao <hychao@chromium.org>
diff --git a/alsa_api_test.c b/alsa_api_test.c
index 55a4740..2122de9 100644
--- a/alsa_api_test.c
+++ b/alsa_api_test.c
@@ -22,14 +22,18 @@
static snd_pcm_uframes_t period_size = 240;
/* Fill frames of zeros. */
-static void pcm_fill_zeros(snd_pcm_t *handle, snd_pcm_uframes_t frames) {
- short *play_buf;
- int err;
+static void pcm_fill(snd_pcm_t *handle, snd_pcm_uframes_t frames,
+ int16_t value) {
+ int16_t *play_buf;
+ int err, i;
play_buf = calloc(frames * channels, sizeof(play_buf[0]));
- printf("Write %d into device\n", (int)frames);
+ for (i = 0; i < frames * channels; i++)
+ play_buf[i] = value;
- if ((err = snd_pcm_writei(handle, play_buf, frames))
+ printf("Write %d of value %d into device\n", (int)frames, (int)value);
+
+ if ((err = snd_pcm_mmap_writei(handle, play_buf, frames))
!= frames) {
fprintf(stderr, "write to audio interface failed (%s)\n",
snd_strerror(err));
@@ -55,7 +59,7 @@
}
if ((err = snd_pcm_hw_params_set_access(handle, hw_params,
- SND_PCM_ACCESS_RW_INTERLEAVED)) < 0) {
+ SND_PCM_ACCESS_MMAP_INTERLEAVED)) < 0) {
fprintf(stderr, "cannot set access type (%s)\n",
snd_strerror(err));
exit(1);
@@ -223,7 +227,7 @@
pcm_init(handle);
- pcm_fill_zeros(handle, buffer_frames);
+ pcm_fill(handle, buffer_frames, 0);
wait_for_periods(handle, wait_periods);
@@ -255,7 +259,7 @@
check_hw_level_in_range(hw_level, 0, fuzz);
/* Fills some zeros after moving to make sure PCM still plays fine. */
- pcm_fill_zeros(handle, period_size * periods_after_move);
+ pcm_fill(handle, period_size * periods_after_move, 0);
hw_level = buffer_frames - snd_pcm_avail(handle);
printf("hw_level after filling %d period is %d\n",
periods_after_move, (int)hw_level);
@@ -289,7 +293,7 @@
pcm_init(handle);
- pcm_fill_zeros(handle, buffer_frames);
+ pcm_fill(handle, buffer_frames, 0);
wait_for_periods(handle, wait_periods);
@@ -339,9 +343,70 @@
}
}
+void alsa_fill_test()
+{
+ int err;
+ snd_pcm_t *handle;
+ unsigned int wait_periods = 10;
+ const snd_pcm_channel_area_t *my_areas;
+ snd_pcm_uframes_t offset, frames;
+ int16_t *dst, *zeros;
+ int n_bytes;
+
+ if ((err = snd_pcm_open(&handle, play_dev,
+ SND_PCM_STREAM_PLAYBACK, 0)) < 0) {
+ fprintf(stderr, "cannot open audio device %s (%s)\n",
+ play_dev, snd_strerror(err));
+ exit(1);
+ }
+
+ pcm_init(handle);
+
+ /* Write nonzero values into buffer. */
+ pcm_fill(handle, buffer_frames, 1);
+
+ /* Play for some periods. */
+ wait_for_periods(handle, wait_periods);
+
+ /* Get the mmap area. */
+ err = snd_pcm_mmap_begin(handle, &my_areas, &offset, &frames);
+ if (err < 0) {
+ fprintf(stderr, "cannot mmap begin (%s)\n", snd_strerror(err));
+ exit(1);
+ }
+
+ /* Fill whole buffer with zeros without committing it.
+ * The number of bytes is buffer_frames * channel * 2 (16 bit sample) */
+ n_bytes = buffer_frames * channels * 2;
+ memset((int8_t *)my_areas[0].addr, 0, n_bytes);
+ printf("Filled mmap buffer with zeros\n");
+
+ /* Play for some periods. */
+ wait_for_periods(handle, wait_periods);
+
+ /* Check the samples in buffer are all zeros. */
+ err = snd_pcm_mmap_begin(handle, &my_areas, &offset, &frames);
+ if (err < 0) {
+ fprintf(stderr, "cannot mmap begin the second time (%s)\n",
+ snd_strerror(err));
+ exit(1);
+ }
+ dst = (int16_t *)my_areas[0].addr;
+
+ zeros = calloc(buffer_frames * channels, sizeof(zeros[0]));
+
+ if (memcmp(zeros, dst, n_bytes)) {
+ fprintf(stderr, "buffer is not all zeros\n");
+ free(zeros);
+ exit(1);
+ }
+ free(zeros);
+ printf("Buffer is filled with zeros\n");
+}
+
int main(int argc, char *argv[])
{
- int c, drop_test = 0, move_test = 0;
+ int c, drop_test = 0, move_test = 0, fill_test = 0;
const char *short_opt = "hd:rm";
struct option long_opt[] =
{
@@ -349,6 +414,7 @@
{"device", required_argument, NULL, 'd'},
{"drop", no_argument, NULL, 'r'},
{"move", no_argument, NULL, 'm'},
+ {"fill", no_argument, NULL, 'f'},
{NULL, 0, NULL, 0 }
};
@@ -372,12 +438,18 @@
printf("Test snd_pcm_forward\n");
break;
+ case 'f':
+ fill_test = 1;
+ printf("Test snd_pcm_mmap_begin and filling buffer.\n");
+ break;
+
case 'h':
printf("Usage: %s [OPTIONS]\n", argv[0]);
printf(" --device <Device> Device, default to hw:0,0\n");
printf(" -h, --help Print this help and exit\n");
printf(" --drop Test snd_pcm_drop\n");
printf(" --move Test snd_pcm_forward\n");
+ printf(" --fill Test snd_pcm_mmap_begin\n");
printf("\n");
return(0);
break;
@@ -406,5 +478,10 @@
exit(0);
}
+ if (fill_test) {
+ alsa_fill_test();
+ exit(0);
+ }
+
exit(0);
}
