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	 c71bb0fb39
			
		
	
	
		c71bb0fb39
		
	
	
	
	
		
			
			BugLink: https://github.com/alsa-project/alsa-lib/issues/132 Signed-off-by: Jaroslav Kysela <perex@perex.cz>
		
			
				
	
	
		
			450 lines
		
	
	
	
		
			13 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			450 lines
		
	
	
	
		
			13 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * This program only tracks the difference between system time
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|  * and audio time, as reported in snd_pcm_status(). It should be
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|  * helpful to verify the information reported by drivers.
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|  */
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| 
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| #include <stdio.h>
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| #include <malloc.h>
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| #include <unistd.h>
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| #include <stdlib.h>
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| #include <string.h>
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| #include <getopt.h>
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| #include <fcntl.h>
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| #include <ctype.h>
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| #include <errno.h>
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| #include <limits.h>
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| #include <time.h>
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| #include <locale.h>
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| #include <math.h>
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| #include "../include/asoundlib.h"
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| 
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| static char *pcm_name = "hw:0";
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| snd_output_t *output = NULL;
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| 
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| static void usage(char *command)
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| {
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| 	printf("Usage: %s [OPTION]... \n"
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| 		"\n"
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| 		"-h, --help              help\n"
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| 		"-c, --capture           capture tstamps \n"
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| 		"-d, --delay             add delay \n"
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| 		"-D, --device=NAME       select PCM by name \n"
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| 		"-p, --playback          playback tstamps \n"
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| 		"-t, --ts_type=TYPE      Compat(0),default(1),link(2),link_absolute(3),link_estimated(4),link_synchronized(5) \n"
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| 		"-r, --report            show audio timestamp and accuracy validity\n"
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| 		, command);
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| }
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| 
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| 
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| long long timestamp2ns(snd_htimestamp_t t)
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| {
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| 	long long nsec;
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| 
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| 	nsec = t.tv_sec * 1000000000ULL;
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| 	nsec += t.tv_nsec;
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| 
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| 	return nsec;
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| }
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| 
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| long long timediff(snd_htimestamp_t t1, snd_htimestamp_t t2)
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| {
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| 	long long nsec1, nsec2;
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| 
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| 	nsec1 = timestamp2ns(t1);
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| 	nsec2 = timestamp2ns(t2);
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| 
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| 	return nsec1 - nsec2;
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| }
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| 
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| void _gettimestamp(snd_pcm_t *handle, snd_htimestamp_t *timestamp,
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| 		   snd_htimestamp_t *trigger_timestamp,
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| 		   snd_htimestamp_t *audio_timestamp,
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| 		   snd_pcm_audio_tstamp_config_t  *audio_tstamp_config,
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| 		   snd_pcm_audio_tstamp_report_t  *audio_tstamp_report,
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| 		   snd_pcm_uframes_t *avail, snd_pcm_sframes_t *delay)
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| {
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| 	int err;
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| 	snd_pcm_status_t *status;
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| 
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| 	snd_pcm_status_alloca(&status);
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| 
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| 	snd_pcm_status_set_audio_htstamp_config(status, audio_tstamp_config);
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| 
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| 	if ((err = snd_pcm_status(handle, status)) < 0) {
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| 		printf("Stream status error: %s\n", snd_strerror(err));
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| 		exit(0);
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| 	}
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| 	snd_pcm_status_get_trigger_htstamp(status, trigger_timestamp);
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| 	snd_pcm_status_get_htstamp(status, timestamp);
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| 	snd_pcm_status_get_audio_htstamp(status, audio_timestamp);
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| 	snd_pcm_status_get_audio_htstamp_report(status, audio_tstamp_report);
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| 	*avail = snd_pcm_status_get_avail(status);
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| 	*delay = snd_pcm_status_get_delay(status);
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| }
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| 
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| #define TIMESTAMP_FREQ 8 /* Hz */
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| #define SAMPLE_FREQ 48000
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| #define PERIOD (SAMPLE_FREQ/TIMESTAMP_FREQ)
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| #define PCM_LINK        /* sync start for playback and capture */
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| #define TRACK_CAPTURE   /* dump capture timing info  */
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| #define TRACK_PLAYBACK  /* dump playback timing info */
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| /*#define TRACK_SAMPLE_COUNTS */ /* show difference between sample counters and audiotimestamps returned by driver */
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| #define PLAYBACK_BUFFERS 4
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| #define TSTAMP_TYPE	SND_PCM_TSTAMP_TYPE_MONOTONIC_RAW
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| 
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| 
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| int main(int argc, char *argv[])
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| {
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| 	int c;
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| 	int err;
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| 	unsigned int i;
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| 	snd_pcm_t *handle_p = NULL;
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| 	snd_pcm_t *handle_c = NULL;
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| 	snd_pcm_sframes_t frames;
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| 	snd_htimestamp_t tstamp_c, tstamp_p;
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| 	snd_htimestamp_t trigger_tstamp_c, trigger_tstamp_p;
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| 	snd_htimestamp_t audio_tstamp_c, audio_tstamp_p;
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| 	unsigned char buffer_p[PERIOD*4*4];
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| 	unsigned char buffer_c[PERIOD*4*4];
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| 
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| 	snd_pcm_hw_params_t *hwparams_p;
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| 	snd_pcm_hw_params_t *hwparams_c;
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| 
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| 	snd_pcm_sw_params_t *swparams_p;
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| 	snd_pcm_sw_params_t *swparams_c;
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| 
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| 	snd_pcm_uframes_t frame_count_c = 0;
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| 	snd_pcm_uframes_t frame_count_p = 0;
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| 
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| 	snd_pcm_sframes_t delay_p, delay_c;
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| 	snd_pcm_uframes_t avail_p, avail_c;
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| 
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| 	snd_pcm_audio_tstamp_config_t audio_tstamp_config_p;
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| 	snd_pcm_audio_tstamp_config_t audio_tstamp_config_c;
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| 	snd_pcm_audio_tstamp_report_t audio_tstamp_report_p;
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| 	snd_pcm_audio_tstamp_report_t audio_tstamp_report_c;
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| 
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| 	int option_index;
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| 	static const char short_options[] = "hcpdrD:t:";
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| 
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| 	static const struct option long_options[] = {
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| 		{"capture", 0, 0, 'c'},
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| 		{"delay", 0, 0, 'd'},
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| 		{"device", required_argument, 0, 'D'},
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| 		{"help", no_argument, 0, 'h'},
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| 		{"playback", 0, 0, 'p'},
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| 		{"ts_type", required_argument, 0, 't'},
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| 		{"report", 0, 0, 'r'},
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| 		{0, 0, 0, 0}
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| 	};
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| 
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| 	int do_delay = 0;
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| 	int do_playback = 0;
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| 	int do_capture = 0;
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| 	int type = 0;
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| 	int do_report = 0;
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| 
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| 	while ((c = getopt_long(argc, argv, short_options, long_options, &option_index)) != -1) {
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| 		switch (c) {
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| 		case 'h':
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| 			usage(argv[0]);
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| 			return 0;
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| 		case 'p':
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| 			do_playback = 1;
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| 			break;
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| 		case 'c':
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| 			do_capture = 1;
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| 			break;
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| 		case 'd':
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| 			do_delay = 1;
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| 			break;
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| 		case 'D':
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| 			pcm_name = optarg;
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| 			break;
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| 		case 't':
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| 			type = atoi(optarg);
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| 			break;
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| 		case 'r':
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| 			do_report = 1;
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| 		}
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| 	}
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| 
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| 	memset(&audio_tstamp_config_p, 0, sizeof(snd_pcm_audio_tstamp_config_t));
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| 	memset(&audio_tstamp_config_c, 0, sizeof(snd_pcm_audio_tstamp_config_t));
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| 	memset(&audio_tstamp_report_p, 0, sizeof(snd_pcm_audio_tstamp_report_t));
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| 	memset(&audio_tstamp_report_c, 0, sizeof(snd_pcm_audio_tstamp_report_t));
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| 
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| 	if (do_playback) {
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| 		if ((err = snd_pcm_open(&handle_p, pcm_name, SND_PCM_STREAM_PLAYBACK, 0)) < 0) {
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| 			printf("Playback open error: %s\n", snd_strerror(err));
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| 			goto _exit;
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| 		}
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| 
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| 		if ((err = snd_pcm_set_params(handle_p,
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| 							SND_PCM_FORMAT_S16,
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| 							SND_PCM_ACCESS_RW_INTERLEAVED,
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| 							2,
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| 							SAMPLE_FREQ,
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| 							0,
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| 							4*1000000/TIMESTAMP_FREQ)) < 0) {
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| 			printf("Playback open error: %s\n", snd_strerror(err));
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| 			goto _exit;
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| 		}
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| 
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| 		snd_pcm_hw_params_alloca(&hwparams_p);
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| /* get the current hwparams */
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| 		err = snd_pcm_hw_params_current(handle_p, hwparams_p);
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| 		if (err < 0) {
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| 			printf("Unable to determine current hwparams_p: %s\n", snd_strerror(err));
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| 			goto _exit;
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| 		}
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| 
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| 		if (snd_pcm_hw_params_supports_audio_ts_type(hwparams_p, SND_PCM_AUDIO_TSTAMP_TYPE_COMPAT))
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| 			printf("Playback supports audio compat timestamps\n");
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| 		if (snd_pcm_hw_params_supports_audio_ts_type(hwparams_p, SND_PCM_AUDIO_TSTAMP_TYPE_DEFAULT))
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| 			printf("Playback supports audio default timestamps\n");
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| 		if (snd_pcm_hw_params_supports_audio_ts_type(hwparams_p, SND_PCM_AUDIO_TSTAMP_TYPE_LINK))
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| 			printf("Playback supports audio link timestamps\n");
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| 		if (snd_pcm_hw_params_supports_audio_ts_type(hwparams_p, SND_PCM_AUDIO_TSTAMP_TYPE_LINK_ABSOLUTE))
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| 			printf("Playback supports audio link absolute timestamps\n");
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| 		if (snd_pcm_hw_params_supports_audio_ts_type(hwparams_p, SND_PCM_AUDIO_TSTAMP_TYPE_LINK_ESTIMATED))
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| 			printf("Playback supports audio link estimated timestamps\n");
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| 		if (snd_pcm_hw_params_supports_audio_ts_type(hwparams_p, SND_PCM_AUDIO_TSTAMP_TYPE_LINK_SYNCHRONIZED))
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| 			printf("Playback supports audio link synchronized timestamps\n");
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| 
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| 		snd_pcm_sw_params_alloca(&swparams_p);
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| 		/* get the current swparams */
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| 		err = snd_pcm_sw_params_current(handle_p, swparams_p);
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| 		if (err < 0) {
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| 			printf("Unable to determine current swparams_p: %s\n", snd_strerror(err));
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| 			goto _exit;
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| 		}
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| 
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| 		/* enable tstamp */
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| 		err = snd_pcm_sw_params_set_tstamp_mode(handle_p, swparams_p, SND_PCM_TSTAMP_ENABLE);
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| 		if (err < 0) {
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| 			printf("Unable to set tstamp mode : %s\n", snd_strerror(err));
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| 			goto _exit;
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| 		}
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| 
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| 		err = snd_pcm_sw_params_set_tstamp_type(handle_p, swparams_p, TSTAMP_TYPE);
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| 		if (err < 0) {
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| 			printf("Unable to set tstamp type : %s\n", snd_strerror(err));
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| 			goto _exit;
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| 		}
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| 
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| 		/* write the sw parameters */
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| 		err = snd_pcm_sw_params(handle_p, swparams_p);
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| 		if (err < 0) {
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| 			printf("Unable to set swparams_p : %s\n", snd_strerror(err));
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| 			goto _exit;
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| 		}
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| 
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| 	}
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| 
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| 	if (do_capture) {
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| 
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| 		if ((err = snd_pcm_open(&handle_c, pcm_name, SND_PCM_STREAM_CAPTURE, SND_PCM_NONBLOCK)) < 0) {
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| 			printf("Capture open error: %s\n", snd_strerror(err));
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| 			goto _exit;
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| 		}
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| 		if ((err = snd_pcm_set_params(handle_c,
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| 							SND_PCM_FORMAT_S16,
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| 							SND_PCM_ACCESS_RW_INTERLEAVED,
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| 							2,
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| 							SAMPLE_FREQ,
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| 							0,
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| 							4*1000000/TIMESTAMP_FREQ)) < 0) {
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| 			printf("Capture open error: %s\n", snd_strerror(err));
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| 			goto _exit;
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| 		}
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| 
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| 		snd_pcm_hw_params_alloca(&hwparams_c);
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| 		/* get the current hwparams */
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| 		err = snd_pcm_hw_params_current(handle_c, hwparams_c);
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| 		if (err < 0) {
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| 			printf("Unable to determine current hwparams_c: %s\n", snd_strerror(err));
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| 			goto _exit;
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| 		}
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| 
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| 		if (snd_pcm_hw_params_supports_audio_ts_type(hwparams_c, SND_PCM_AUDIO_TSTAMP_TYPE_COMPAT))
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| 			printf("Capture supports audio compat timestamps\n");
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| 		if (snd_pcm_hw_params_supports_audio_ts_type(hwparams_c, SND_PCM_AUDIO_TSTAMP_TYPE_DEFAULT))
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| 			printf("Capture supports audio default timestamps\n");
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| 		if (snd_pcm_hw_params_supports_audio_ts_type(hwparams_c, SND_PCM_AUDIO_TSTAMP_TYPE_LINK))
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| 			printf("Capture supports audio link timestamps\n");
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| 		if (snd_pcm_hw_params_supports_audio_ts_type(hwparams_c, SND_PCM_AUDIO_TSTAMP_TYPE_LINK_ABSOLUTE))
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| 			printf("Capture supports audio link absolute timestamps\n");
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| 		if (snd_pcm_hw_params_supports_audio_ts_type(hwparams_c, SND_PCM_AUDIO_TSTAMP_TYPE_LINK_ESTIMATED))
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| 			printf("Capture supports audio link estimated timestamps\n");
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| 		if (snd_pcm_hw_params_supports_audio_ts_type(hwparams_c, SND_PCM_AUDIO_TSTAMP_TYPE_LINK_SYNCHRONIZED))
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| 			printf("Capture supports audio link synchronized timestamps\n");
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| 
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| 		snd_pcm_sw_params_alloca(&swparams_c);
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| 		/* get the current swparams */
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| 		err = snd_pcm_sw_params_current(handle_c, swparams_c);
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| 		if (err < 0) {
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| 			printf("Unable to determine current swparams_c: %s\n", snd_strerror(err));
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| 			goto _exit;
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| 		}
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| 
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| 		/* enable tstamp */
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| 		err = snd_pcm_sw_params_set_tstamp_mode(handle_c, swparams_c, SND_PCM_TSTAMP_ENABLE);
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| 		if (err < 0) {
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| 			printf("Unable to set tstamp mode : %s\n", snd_strerror(err));
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| 			goto _exit;
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| 		}
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| 
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| 		err = snd_pcm_sw_params_set_tstamp_type(handle_c, swparams_c, TSTAMP_TYPE);
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| 		if (err < 0) {
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| 			printf("Unable to set tstamp type : %s\n", snd_strerror(err));
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| 			goto _exit;
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| 		}
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| 
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| 		/* write the sw parameters */
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| 		err = snd_pcm_sw_params(handle_c, swparams_c);
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| 		if (err < 0) {
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| 			printf("Unable to set swparams_c : %s\n", snd_strerror(err));
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| 			goto _exit;
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| 		}
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| 	}
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| 
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| 	if (do_playback && do_capture) {
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| #ifdef PCM_LINK
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| 		if ((err = snd_pcm_link(handle_c, handle_p)) < 0) {
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| 			printf("Streams link error: %s\n", snd_strerror(err));
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| 			exit(0);
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| 		}
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| #endif
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| 	}
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| 
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| 	if (do_playback) {
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| 		i = PLAYBACK_BUFFERS;
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| 		while (i--) {
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| 			frames = snd_pcm_writei(handle_p, buffer_p, PERIOD);
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| 			if (frames < 0) {
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| 				printf("snd_pcm_writei failed: %s\n", snd_strerror(frames));
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| 				goto _exit;
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| 			}
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| 			frame_count_p += frames;
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| 		}
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| 
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| 		if (PLAYBACK_BUFFERS != 4)
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| 			snd_pcm_start(handle_p);
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| 	}
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| 
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| 	if (do_capture) {
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| #ifndef PCM_LINK
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| 		/* need to start capture explicitly */
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| 		snd_pcm_start(handle_c);
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| #else
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| 		if (!do_playback)
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| 			/* need to start capture explicitly */
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| 			snd_pcm_start(handle_c);
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| #endif
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| 	}
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| 
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| 	while (1) {
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| 
 | |
| 		if (do_capture) {
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| 
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| 			frames = snd_pcm_wait(handle_c, -1);
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| 			if (frames < 0) {
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| 				printf("snd_pcm_wait failed: %s\n", snd_strerror(frames));
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| 				goto _exit;
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| 			}
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| 
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| 			frames = snd_pcm_readi(handle_c, buffer_c, PERIOD);
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| 			if (frames < 0) {
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| 				printf("snd_pcm_readi failed: %s\n", snd_strerror(frames));
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| 				goto _exit;
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| 			}
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| 			frame_count_c += frames;
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| 
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| #if defined(TRACK_CAPTURE)
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| 			audio_tstamp_config_c.type_requested = type;
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| 			audio_tstamp_config_c.report_delay = do_delay;
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| 			_gettimestamp(handle_c, &tstamp_c, &trigger_tstamp_c,
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| 				&audio_tstamp_c, &audio_tstamp_config_c, &audio_tstamp_report_c,
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| 				&avail_c, &delay_c);
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| #if defined(TRACK_SAMPLE_COUNTS)
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| 			curr_count_c = frame_count_c + delay_c; /* read plus queued */
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| 
 | |
| 
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| 			printf("capture: curr_count %lli driver count %lli, delta %lli\n",
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| 				(long long)curr_count_c * 1000000000LL / SAMPLE_FREQ ,
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| 				timestamp2ns(audio_tstamp_c),
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| 				(long long)curr_count_c * 1000000000LL / SAMPLE_FREQ - timestamp2ns(audio_tstamp_c)
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| 				);
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| #endif
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| 			if (do_report) {
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| 				if (audio_tstamp_report_c.valid == 0)
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| 					printf("Audio capture timestamp report invalid - ");
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| 				if (audio_tstamp_report_c.accuracy_report == 0)
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| 					printf("Audio capture timestamp accuracy report invalid");
 | |
| 				printf("\n");
 | |
| 			}
 | |
| 
 | |
| 
 | |
| 			printf("\t capture: systime: %lli nsec, audio time %lli nsec, \tsystime delta %lli \t resolution %d ns \n", 
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| 				timediff(tstamp_c, trigger_tstamp_c),
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| 				timestamp2ns(audio_tstamp_c),
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| 				timediff(tstamp_c, trigger_tstamp_c) - timestamp2ns(audio_tstamp_c), audio_tstamp_report_c.accuracy
 | |
| 				);
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| #endif
 | |
| 		}
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| 
 | |
| 		if (do_playback) {
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| 			frames = snd_pcm_writei(handle_p, buffer_p, PERIOD);
 | |
| 			if (frames < 0) {
 | |
| 				printf("snd_pcm_writei failed: %s\n", snd_strerror(frames));
 | |
| 				goto _exit;
 | |
| 			}
 | |
| 
 | |
| 			frame_count_p += frames;
 | |
| 
 | |
| #if defined(TRACK_PLAYBACK)
 | |
| 
 | |
| 			audio_tstamp_config_p.type_requested = type;
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| 			audio_tstamp_config_p.report_delay = do_delay;
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| 			_gettimestamp(handle_p, &tstamp_p, &trigger_tstamp_p,
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| 				&audio_tstamp_p, &audio_tstamp_config_p, &audio_tstamp_report_p,
 | |
| 				&avail_p, &delay_p);
 | |
| 
 | |
| #if defined(TRACK_SAMPLE_COUNTS)
 | |
| 			curr_count_p = frame_count_p - delay_p; /* written minus queued */
 | |
| 
 | |
| 			printf("playback: curr_count %lli driver count %lli, delta %lli\n",
 | |
| 				(long long)curr_count_p * 1000000000LL / SAMPLE_FREQ ,
 | |
| 				timestamp2ns(audio_tstamp_p),
 | |
| 				(long long)curr_count_p * 1000000000LL / SAMPLE_FREQ - timestamp2ns(audio_tstamp_p)
 | |
| 				);
 | |
| #endif
 | |
| 			if (do_report) {
 | |
| 				if (audio_tstamp_report_p.valid == 0)
 | |
| 					printf("Audio playback timestamp report invalid - ");
 | |
| 				if (audio_tstamp_report_p.accuracy_report == 0)
 | |
| 					printf("Audio playback timestamp accuracy report invalid");
 | |
| 				printf("\n");
 | |
| 			}
 | |
| 
 | |
| 			printf("playback: systime: %lli nsec, audio time %lli nsec, \tsystime delta %lli resolution %d ns\n",
 | |
| 				timediff(tstamp_p, trigger_tstamp_p),
 | |
| 				timestamp2ns(audio_tstamp_p),
 | |
| 				timediff(tstamp_p, trigger_tstamp_p) - timestamp2ns(audio_tstamp_p), audio_tstamp_report_p.accuracy
 | |
| 				);
 | |
| #endif
 | |
| 		}
 | |
| 
 | |
| 
 | |
| 	} /* while(1) */
 | |
| 
 | |
| _exit:
 | |
| 	if (handle_p)
 | |
| 		snd_pcm_close(handle_p);
 | |
| 	if (handle_c)
 | |
| 		snd_pcm_close(handle_c);
 | |
| 
 | |
| 	return 0;
 | |
| }
 |