tests/kms_chamelium: capture audio data in real-time

Before this patch, the audio test first sends an audio signal for 2s, and then
checks whether the captured signal matches.

This patch makes it so we send and check the signal in parallel. Thus we can
stop the test as soon as we receive the correct signal. This saves ~2s per
audio test.

Signed-off-by: Simon Ser <simon.ser@intel.com>
Reviewed-by: Martin Peres <martin.peres@linux.intel.com>

2 files changed, 43 insertions, 19 deletions

diff --git a/lib/igt_alsa.c b/lib/igt_alsa.c
index 22089881..fc6d336b 100644
--- a/lib/igt_alsa.c
+++ b/lib/igt_alsa.c
@@ -497,7 +497,8 @@ void alsa_register_input_callback(struct alsa *alsa,
 /**
  * alsa_run:
  * @alsa: The target alsa structure
- * @duration_ms: The maximum duration of the run in milliseconds
+ * @duration_ms: The maximum duration of the run in milliseconds, or -1 for an
+ * infinite duration.
  *
  * Run ALSA playback and capture on the input and output devices for at
  * most @duration_ms milliseconds, calling the registered callbacks when needed.
@@ -545,7 +546,7 @@ int alsa_run(struct alsa *alsa, int duration_ms)
 	do {
 		reached = true;
 
-		if (output_total < output_limit) {
+		if (output_limit < 0 || output_total < output_limit) {
 			reached = false;
 
 			if (!output_ready) {
@@ -607,7 +608,8 @@ int alsa_run(struct alsa *alsa, int duration_ms)
 
 		}
 
-		if (alsa->input_callback && input_total < input_limit) {
+		if (alsa->input_callback &&
+		    (input_limit < 0 || input_total < input_limit)) {
 			reached = false;
 
 			if (input_count == input_trigger) {
@@ -660,11 +662,8 @@ int alsa_run(struct alsa *alsa, int duration_ms)
 	ret = 0;
 
 complete:
-	if (output_buffer)
-		free(output_buffer);
-
-	if (input_buffer)
-		free(input_buffer);
+	free(output_buffer);
+	free(input_buffer);
 
 	return ret;
 }
diff --git a/tests/kms_chamelium.c b/tests/kms_chamelium.c
index a712250a..014a22b3 100644
--- a/tests/kms_chamelium.c
+++ b/tests/kms_chamelium.c
@@ -29,7 +29,9 @@
 #include "igt_vc4.h"
 
 #include <fcntl.h>
+#include <pthread.h>
 #include <string.h>
+#include <stdatomic.h>
 
 typedef struct {
 	struct chamelium *chamelium;
@@ -719,7 +721,7 @@ test_display_frame_dump(data_t *data, struct chamelium_port *port)
 /* Capture paremeters control the audio signal we receive */
 #define CAPTURE_SAMPLES 2048
 
-#define AUDIO_DURATION 2000 /* ms */
+#define AUDIO_TIMEOUT 2000 /* ms */
 /* A streak of 3 gives confidence that the signal is good. */
 #define MIN_STREAK 3
 
@@ -746,14 +748,28 @@ static int test_frequencies[] = {
 
 static int test_frequencies_count = sizeof(test_frequencies) / sizeof(int);
 
+struct audio_state {
+	struct audio_signal *signal;
+	atomic_bool run;
+};
+
 static int
-output_callback(void *data, short *buffer, int frames)
+audio_output_callback(void *data, short *buffer, int frames)
 {
-	struct audio_signal *signal = (struct audio_signal *) data;
+	struct audio_state *state = data;
+
+	audio_signal_fill(state->signal, buffer, frames);
 
-	audio_signal_fill(signal, buffer, frames);
+	return state->run ? 0 : -1;
+}
+
+static void *
+run_audio_thread(void *data)
+{
+	struct alsa *alsa = data;
 
-	return 0;
+	alsa_run(alsa, -1);
+	return NULL;
 }
 
 static bool
@@ -774,6 +790,8 @@ do_test_display_audio(data_t *data, struct chamelium_port *port,
 	char dump_suffix[64];
 	char *dump_path = NULL;
 	int dump_fd = -1;
+	pthread_t thread;
+	struct audio_state state = {};
 
 	if (!alsa_test_output_configuration(alsa, playback_channels,
 					    playback_rate))
@@ -811,15 +829,15 @@ do_test_display_audio(data_t *data, struct chamelium_port *port,
 		audio_signal_add_frequency(signal, test_frequencies[i]);
 	audio_signal_synthesize(signal);
 
-	alsa_register_output_callback(alsa, output_callback, signal,
+	state.signal = signal;
+	state.run = true;
+	alsa_register_output_callback(alsa, audio_output_callback, &state,
 				      PLAYBACK_SAMPLES);
 
-	/* TODO: detect signal in real-time */
-	ret = alsa_run(alsa, AUDIO_DURATION);
+	/* Start playing audio */
+	ret = pthread_create(&thread, NULL, run_audio_thread, alsa);
 	igt_assert(ret == 0);
 
-	alsa_close_output(alsa);
-
 	/* Needs to be a multiple of 128, because that's the number of samples
 	 * we get per channel each time we receive an audio page from the
 	 * Chamelium device. */
@@ -836,7 +854,7 @@ do_test_display_audio(data_t *data, struct chamelium_port *port,
 	streak = 0;
 	msec = 0;
 	i = 0;
-	while (streak < MIN_STREAK && msec < AUDIO_DURATION) {
+	while (streak < MIN_STREAK && msec < AUDIO_TIMEOUT) {
 		ok = chamelium_stream_receive_realtime_audio(stream,
 							     &page_count,
 							     &recv, &recv_len);
@@ -871,6 +889,13 @@ do_test_display_audio(data_t *data, struct chamelium_port *port,
 		i++;
 	}
 
+	igt_debug("Stopping audio playback\n");
+	state.run = false;
+	ret = pthread_join(thread, NULL);
+	igt_assert(ret == 0);
+
+	alsa_close_output(alsa);
+
 	if (dump_fd >= 0) {
 		close(dump_fd);
 		if (streak == MIN_STREAK) {