* *
*****************************************************************************/
-#define SNDRV_PCM_VERSION SNDRV_PROTOCOL_VERSION(2, 0, 10)
+#define SNDRV_PCM_VERSION SNDRV_PROTOCOL_VERSION(2, 0, 11)
typedef unsigned long sndrv_pcm_uframes_t;
typedef long sndrv_pcm_sframes_t;
#define SNDRV_PCM_INFO_JOINT_DUPLEX 0x00200000 /* playback and capture stream are somewhat correlated */
#define SNDRV_PCM_INFO_SYNC_START 0x00400000 /* pcm support some kind of sync go */
#define SNDRV_PCM_INFO_NO_PERIOD_WAKEUP 0x00800000 /* period wakeup can be disabled */
+#define SNDRV_PCM_INFO_HAS_WALL_CLOCK 0x01000000 /* has audio wall clock for audio/system time sync */
enum sndrv_pcm_state {
SNDRV_PCM_STATE_OPEN = 0, /* stream is open */
sndrv_pcm_uframes_t avail_max; /* max frames available on hw since last status */
sndrv_pcm_uframes_t overrange; /* count of ADC (capture) overrange detections from last status */
int suspended_state; /* suspended stream state */
- unsigned char reserved[60]; /* must be filled with zero */
+ struct timespec audio_tstamp; /* from sample counter or wall clock */
+ unsigned char reserved[60-sizeof(struct timespec)]; /* must be filled with zero */
};
struct sndrv_pcm_mmap_status {
sndrv_pcm_uframes_t hw_ptr; /* RO: hw ptr (0...boundary-1) */
struct timespec tstamp; /* Timestamp */
int suspended_state; /* RO: suspended stream state */
+ struct timespec audio_tstamp; /* from sample counter or wall clock */
};
struct sndrv_pcm_mmap_control {
return !!(params->info & SNDRV_PCM_INFO_NO_PERIOD_WAKEUP);
}
+/**
+ * \brief Check if hardware supports audio wallclock timestamps
+ * \param params Configuration space
+ * \retval 0 Hardware doesn't support audio wallclock timestamps
+ * \retval 1 Hardware supports audio wallclock timestamps
+ *
+ * This function should only be called when the configuration space
+ * contains a single configuration. Call #snd_pcm_hw_params to choose
+ * a single configuration from the configuration space.
+ */
+int snd_pcm_hw_params_supports_audio_wallclock_ts(const snd_pcm_hw_params_t *params)
+{
+ assert(params);
+ if (CHECK_SANITY(params->info == ~0U)) {
+ SNDMSG("invalid PCM info field");
+ return 0; /* FIXME: should be a negative error? */
+ }
+ return !!(params->info & SNDRV_PCM_INFO_HAS_WALL_CLOCK);
+}
+
/**
* \brief Get rate exact info from a configuration space
* \param params Configuration space
use_default_symbol_version(__snd_pcm_status_get_htstamp, snd_pcm_status_get_htstamp, ALSA_0.9.0rc8);
/**
+ * \brief Get "now" hi-res audio timestamp from a PCM status container
+ * \param obj pointer to #snd_pcm_status_t
+ * \param ptr Pointer to returned timestamp
+ */
+void snd_pcm_status_get_audio_htstamp(const snd_pcm_status_t *obj, snd_htimestamp_t *ptr)
+{
+ assert(obj && ptr);
+ *ptr = obj->audio_tstamp;
+}
+
+/**
* \brief Get delay from a PCM status container (see #snd_pcm_delay)
* \return Delay in frames
*
void gettimestamp(snd_pcm_t *handle, snd_htimestamp_t *timestamp,
snd_htimestamp_t *trigger_timestamp,
+ snd_htimestamp_t *audio_timestamp,
snd_pcm_uframes_t *avail, snd_pcm_sframes_t *delay)
{
int err;
}
snd_pcm_status_get_trigger_htstamp(status, trigger_timestamp);
snd_pcm_status_get_htstamp(status, timestamp);
+ snd_pcm_status_get_audio_htstamp(status, audio_timestamp);
*avail = snd_pcm_status_get_avail(status);
*delay = snd_pcm_status_get_delay(status);
}
#define PCM_LINK /* sync start for playback and capture */
#define TRACK_CAPTURE /* dump capture timing info */
#define TRACK_PLAYBACK /* dump playback timing info */
+#define TRACK_SAMPLE_COUNTS /* show difference between sample counters and audiotimestamps returned by driver */
#define PLAYBACK_BUFFERS 4
snd_pcm_sframes_t frames;
snd_htimestamp_t tstamp_c, tstamp_p;
snd_htimestamp_t trigger_tstamp_c, trigger_tstamp_p;
+ snd_htimestamp_t audio_tstamp_c, audio_tstamp_p;
unsigned char buffer_p[PERIOD*4*4];
unsigned char buffer_c[PERIOD*4*4];
+ snd_pcm_hw_params_t *hwparams_p;
+ snd_pcm_hw_params_t *hwparams_c;
+
snd_pcm_sw_params_t *swparams_p;
snd_pcm_sw_params_t *swparams_c;
goto _exit;
}
+ snd_pcm_hw_params_alloca(&hwparams_p);
+ /* get the current hwparams */
+ err = snd_pcm_hw_params_current(handle_p, hwparams_p);
+ if (err < 0) {
+ printf("Unable to determine current hwparams_p: %s\n", snd_strerror(err));
+ goto _exit;
+ }
+ if (snd_pcm_hw_params_supports_audio_wallclock_ts(hwparams_p))
+ printf("Playback relies on audio wallclock timestamps\n");
+ else
+ printf("Playback relies on audio sample counter timestamps\n");
+
snd_pcm_sw_params_alloca(&swparams_p);
/* get the current swparams */
err = snd_pcm_sw_params_current(handle_p, swparams_p);
goto _exit;
}
+ snd_pcm_hw_params_alloca(&hwparams_c);
+ /* get the current hwparams */
+ err = snd_pcm_hw_params_current(handle_c, hwparams_c);
+ if (err < 0) {
+ printf("Unable to determine current hwparams_c: %s\n", snd_strerror(err));
+ goto _exit;
+ }
+ if (snd_pcm_hw_params_supports_audio_wallclock_ts(hwparams_c))
+ printf("Capture relies on audio wallclock timestamps\n");
+ else
+ printf("Capture relies on audio sample counter timestamps\n");
+
snd_pcm_sw_params_alloca(&swparams_c);
/* get the current swparams */
err = snd_pcm_sw_params_current(handle_c, swparams_c);
frame_count_p += frames;
#if defined(TRACK_PLAYBACK)
- gettimestamp(handle_p, &tstamp_p, &trigger_tstamp_p, &avail_p, &delay_p);
+ gettimestamp(handle_p, &tstamp_p, &trigger_tstamp_p, &audio_tstamp_p, &avail_p, &delay_p);
+#if defined(TRACK_SAMPLE_COUNTS)
curr_count_p = frame_count_p - delay_p; /* written minus queued */
- printf("playback: systime: %lli nsec, sample time %lli nsec \tsystime delta %lli \n",
- timediff(tstamp_p,trigger_tstamp_p),
- (long long)round(((float)curr_count_p * 1000000000.0 / 48000.0)),
- timediff(tstamp_p, trigger_tstamp_p) - (long long)round((double)curr_count_p * 1000000000.0 / 48000.0)
+ printf("playback: curr_count %lli driver count %lli, delta %lli\n",
+ (long long)curr_count_p * 1000000000LL / 48000 ,
+ timestamp2ns(audio_tstamp_p),
+ (long long)curr_count_p * 1000000000LL / 48000 - timestamp2ns(audio_tstamp_p)
+ );
+#endif
+
+ printf("playback: systime: %lli nsec, audio time %lli nsec, \tsystime delta %lli\n",
+ timediff(tstamp_p, trigger_tstamp_p),
+ timestamp2ns(audio_tstamp_p),
+ timediff(tstamp_p, trigger_tstamp_p) - timestamp2ns(audio_tstamp_p)
);
#endif
#if defined(TRACK_CAPTURE)
- gettimestamp(handle_c, &tstamp_c, &trigger_tstamp_c, &avail_c, &delay_c);
+ gettimestamp(handle_c, &tstamp_c, &trigger_tstamp_c, &audio_tstamp_c, &avail_c, &delay_c);
+#if defined(TRACK_SAMPLE_COUNTS)
curr_count_c = frame_count_c + delay_c; /* read plus queued */
- printf("\t capture: systime: %lli nsec, sample time %lli nsec \tsystime delta %lli \n",
- timediff(tstamp_c,trigger_tstamp_c),
- (long long)round(((float)curr_count_c * 1000000000.0 / 48000.0)),
- timediff(tstamp_c, trigger_tstamp_c) - (long long)round((double)curr_count_c * 1000000000.0 / 48000.0)
+
+ printf("capture: curr_count %lli driver count %lli, delta %lli\n",
+ (long long)curr_count_c * 1000000000LL / 48000 ,
+ timestamp2ns(audio_tstamp_c),
+ (long long)curr_count_c * 1000000000LL / 48000 - timestamp2ns(audio_tstamp_c)
+ );
+#endif
+
+ printf("\t capture: systime: %lli nsec, audio time %lli nsec, \tsystime delta %lli\n",
+ timediff(tstamp_c, trigger_tstamp_c),
+ timestamp2ns(audio_tstamp_c),
+ timediff(tstamp_c, trigger_tstamp_c) - timestamp2ns(audio_tstamp_c)
);
#endif
git://git.alsa-project.org / alsa-lib.git / commitdiff