mirrors/pipewire
1
0
Fork 0
mirror of https://gitlab.freedesktop.org/pipewire/pipewire.git synced 2025-10-29 05:40:27 -04:00
Code Issues Projects Releases Packages Wiki Activity Actions

alsa: use 2 (or 3 for batch) periods in IRQ mode

Browse source 
Some drivers (Firewire) have a latency depending on the ALSA buffer size
instead of the period size.

In IRQ mode, we can safely use 2 (or 3 for batch devices) periods
because we always need to reconfigure the hardware when we want to
change the period and so we don't need to keep some headroom like we do
for timer based scheduling.

See #4785
This commit is contained in:
Wim Taymans 2025-09-02 14:13:19 +02:00
parent fabfdb1b01
commit 124aa40f64
1 changed files with 7 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

9
spa/plugins/alsa/alsa-pcm.c
View file

@ -2335,8 +2335,13 @@ int spa_alsa_set_format(struct state *state, struct spa_audio_info *fmt, uint32_
state->period_frames = period_size; state->period_frames = period_size;
if (state->default_period_num != 0) { if (state->default_period_num != 0 || state->disable_tsched) {
periods = state->default_period_num; if (state->default_period_num != 0)
/* period number given use that */
periods = state->default_period_num;
else
/* IRQ mode, use 2 periods or 3 for batch */
periods = state->is_batch ? 3 : 2;
CHECK(snd_pcm_hw_params_set_periods_near(hndl, params, &periods, &dir), "set_periods"); CHECK(snd_pcm_hw_params_set_periods_near(hndl, params, &periods, &dir), "set_periods");
state->buffer_frames = period_size * periods; state->buffer_frames = period_size * periods;
} else { } else {