1 From bbf9c767d5b353142e03080762bdd805e124d50b Mon Sep 17 00:00:00 2001
2 From: Walter Lozano <walter.lozano@collabora.com>
3 Date: Fri, 7 Aug 2020 10:58:29 -0300
4 Subject: [PATCH] alsa: Set period_size depending on hardware
6 Currently PipeWire is unable to reproduce audio in systems where DMA
7 granularity is not burst.
9 In order to mitigate this issue, set period_size depending on hardware,
10 lowering it when snd_pcm_hw_params_is_batch == 1, to reduce DMA
13 Signed-off-by: Walter Lozano <walter.lozano@collabora.com>
15 spa/plugins/alsa/alsa-pcm.c | 4 ++++
16 1 file changed, 4 insertions(+)
18 diff --git a/spa/plugins/alsa/alsa-pcm.c b/spa/plugins/alsa/alsa-pcm.c
19 index 63d75549..2d3850b7 100644
20 --- a/spa/plugins/alsa/alsa-pcm.c
21 +++ b/spa/plugins/alsa/alsa-pcm.c
22 @@ -463,6 +463,10 @@ int spa_alsa_set_format(struct state *state, struct spa_audio_info *fmt, uint32_
26 + if (snd_pcm_hw_params_is_batch(params)) {
28 + spa_log_warn(state->log, NAME" hardware does double buffering, changing period_size to %ld", period_size);
30 CHECK(snd_pcm_hw_params_set_period_size_near(hndl, params, &period_size, &dir), "set_period_size_near");
31 CHECK(snd_pcm_hw_params_get_buffer_size_max(params, &state->buffer_frames), "get_buffer_size_max");
32 CHECK(snd_pcm_hw_params_set_buffer_size_near(hndl, params, &state->buffer_frames), "set_buffer_size_near");