ext: alsa: Set buffer time after period time

This because underlying driver may have constraint on
buffer size to be dependent on period size, so period
time needs to be set first.

For e.g. Xilinx ASoC driver requires
buffer size to be multiple of period size for it's DMA
operation.

alsa-utils also set period time first as seen in below commit :
9b621eeac4

Tested it on zcu106 board with HDMI based record and playback.
Also tested on Intel PC using Logitech C920 Webcam mic and ALC887-VD
Analog for playback.

Part-of: <https://gitlab.freedesktop.org/gstreamer/gst-plugins-base/-/merge_requests/1040>
This commit is contained in:
Devarsh Thakkar 2021-02-09 05:16:34 -08:00 committed by GStreamer Marge Bot
parent 01d1bbd1da
commit 9759810d82
2 changed files with 85 additions and 34 deletions

View file

@ -492,40 +492,68 @@ retry:
GST_DEBUG_OBJECT (alsa, "periods min %u, max %u", min, max); GST_DEBUG_OBJECT (alsa, "periods min %u, max %u", min, max);
} }
#endif #endif
if (!alsa->iec958) {
/* now try to configure the buffer time and period time, if one /* Following pulseaudio's approach in
* of those fail, we fall back to the defaults and emit a warning. */ * https://gitlab.freedesktop.org/pulseaudio/pulseaudio/-/commit/557c4295107dc7374c850b0bd5331dd35e8fdd0f
if (buffer_time != -1 && !alsa->iec958) { * we'll try various configuration to set the buffer time and period time as some
/* set the buffer time */ * driver can be picky on the order of the calls.
if ((err = snd_pcm_hw_params_set_buffer_time_near (alsa->handle, params, */
&buffer_time, NULL)) < 0) { if (buffer_time != -1 && period_time != -1) {
GST_ELEMENT_WARNING (alsa, RESOURCE, SETTINGS, (NULL), if (((err = snd_pcm_hw_params_set_buffer_time_near (alsa->handle, params,
("Unable to set buffer time %i for playback: %s", &buffer_time, NULL)) >= 0)
buffer_time, snd_strerror (err))); && ((err =
/* disable buffer_time the next round */ snd_pcm_hw_params_set_period_time_near (alsa->handle, params,
buffer_time = -1; &period_time, NULL)) >= 0)) {
goto retry; GST_DEBUG_OBJECT (alsa, "buffer time %u period time %u set correctly",
buffer_time, period_time);
alsa->buffer_time = buffer_time;
alsa->period_time = period_time;
goto buffer_period_set;
}
if (((err = snd_pcm_hw_params_set_period_time_near (alsa->handle, params,
&period_time, NULL)) >= 0)
&& ((err =
snd_pcm_hw_params_set_buffer_time_near (alsa->handle, params,
&buffer_time, NULL)) >= 0)) {
GST_DEBUG_OBJECT (alsa, "period time %u buffer time %u set correctly",
period_time, buffer_time);
alsa->buffer_time = buffer_time;
alsa->period_time = period_time;
goto buffer_period_set;
}
} }
GST_DEBUG_OBJECT (alsa, "buffer time %u", buffer_time); /* now try to configure the buffer time and period time independently, if one
alsa->buffer_time = buffer_time; * of those fail, we fall back to the defaults and emit a warning. */
} if (buffer_time != -1) {
if (period_time != -1 && !alsa->iec958) { /* set the buffer time */
/* set the period time */ if ((err = snd_pcm_hw_params_set_buffer_time_near (alsa->handle, params,
if ((err = snd_pcm_hw_params_set_period_time_near (alsa->handle, params, &buffer_time, NULL)) < 0) {
&period_time, NULL)) < 0) { GST_ELEMENT_WARNING (alsa, RESOURCE, SETTINGS, (NULL),
GST_ELEMENT_WARNING (alsa, RESOURCE, SETTINGS, (NULL), ("Unable to set buffer time %i for playback: %s",
("Unable to set period time %i for playback: %s", buffer_time, snd_strerror (err)));
period_time, snd_strerror (err))); /* disable buffer_time the next round */
/* disable period_time the next round */ buffer_time = -1;
period_time = -1; goto retry;
goto retry; }
GST_DEBUG_OBJECT (alsa, "buffer time %u set correctly", buffer_time);
alsa->buffer_time = buffer_time;
} }
GST_DEBUG_OBJECT (alsa, "period time %u", period_time); if (period_time != -1) {
alsa->period_time = period_time; /* set the period time */
} if ((err = snd_pcm_hw_params_set_period_time_near (alsa->handle, params,
&period_time, NULL)) < 0) {
/* Set buffer size and period size manually for SPDIF */ GST_ELEMENT_WARNING (alsa, RESOURCE, SETTINGS, (NULL),
if (G_UNLIKELY (alsa->iec958)) { ("Unable to set period time %i for playback: %s",
period_time, snd_strerror (err)));
/* disable period_time the next round */
period_time = -1;
goto retry;
}
GST_DEBUG_OBJECT (alsa, "period time %u set correctly", period_time);
alsa->period_time = period_time;
}
} else {
/* Set buffer size and period size manually for SPDIF */
snd_pcm_uframes_t buffer_size = SPDIF_BUFFER_SIZE; snd_pcm_uframes_t buffer_size = SPDIF_BUFFER_SIZE;
snd_pcm_uframes_t period_size = SPDIF_PERIOD_SIZE; snd_pcm_uframes_t period_size = SPDIF_PERIOD_SIZE;
@ -534,7 +562,7 @@ retry:
CHECK (snd_pcm_hw_params_set_period_size_near (alsa->handle, params, CHECK (snd_pcm_hw_params_set_period_size_near (alsa->handle, params,
&period_size, NULL), period_size); &period_size, NULL), period_size);
} }
buffer_period_set:
/* write the parameters to device */ /* write the parameters to device */
CHECK (snd_pcm_hw_params (alsa->handle, params), set_hw_params); CHECK (snd_pcm_hw_params (alsa->handle, params), set_hw_params);

View file

@ -415,7 +415,29 @@ set_hwparams (GstAlsaSrc * alsa)
GST_DEBUG_OBJECT (alsa, "periods min %u, max %u", min, max); GST_DEBUG_OBJECT (alsa, "periods min %u, max %u", min, max);
} }
#endif #endif
/* Following pulseaudio's approach in
* https://gitlab.freedesktop.org/pulseaudio/pulseaudio/-/commit/557c4295107dc7374c850b0bd5331dd35e8fdd0f
* we'll try various configuration to set the buffer time and period time as some
* driver can be picky on the order of the calls.
*/
if (alsa->period_time != -1 && alsa->buffer_time != -1) {
if ((snd_pcm_hw_params_set_buffer_time_near (alsa->handle, params,
&alsa->buffer_time, NULL) >= 0)
&& (snd_pcm_hw_params_set_period_time_near (alsa->handle, params,
&alsa->period_time, NULL) >= 0)) {
GST_DEBUG_OBJECT (alsa, "buffer time %u period time %u set correctly",
alsa->buffer_time, alsa->period_time);
goto buffer_period_set;
}
if ((snd_pcm_hw_params_set_period_time_near (alsa->handle, params,
&alsa->period_time, NULL) >= 0)
&& (snd_pcm_hw_params_set_buffer_time_near (alsa->handle, params,
&alsa->buffer_time, NULL) >= 0)) {
GST_DEBUG_OBJECT (alsa, "period time %u buffer time %u set correctly",
alsa->period_time, alsa->buffer_time);
goto buffer_period_set;
}
}
if (alsa->buffer_time != -1) { if (alsa->buffer_time != -1) {
/* set the buffer time */ /* set the buffer time */
CHECK (snd_pcm_hw_params_set_buffer_time_near (alsa->handle, params, CHECK (snd_pcm_hw_params_set_buffer_time_near (alsa->handle, params,
@ -429,6 +451,7 @@ set_hwparams (GstAlsaSrc * alsa)
GST_DEBUG_OBJECT (alsa, "period time %u", alsa->period_time); GST_DEBUG_OBJECT (alsa, "period time %u", alsa->period_time);
} }
buffer_period_set:
/* write the parameters to device */ /* write the parameters to device */
CHECK (snd_pcm_hw_params (alsa->handle, params), set_hw_params); CHECK (snd_pcm_hw_params (alsa->handle, params), set_hw_params);