Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

ALSA: fix buffer size / period size configuration #917

Open
wants to merge 1 commit into
base: master
Choose a base branch
from
Open
Changes from all commits
Commits
File filter

Filter by extension

Filter by extension

Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
21 changes: 11 additions & 10 deletions src/host/alsa/mod.rs
Original file line number Diff line number Diff line change
Expand Up @@ -1061,18 +1061,19 @@ fn set_hw_params_from_format(
hw_params.set_rate(config.sample_rate.0, alsa::ValueOr::Nearest)?;
hw_params.set_channels(config.channels as u32)?;

match config.buffer_size {
BufferSize::Fixed(v) => {
hw_params.set_period_size_near((v / 4) as alsa::pcm::Frames, alsa::ValueOr::Nearest)?;
hw_params.set_buffer_size(v as alsa::pcm::Frames)?;
}
let period_size = match config.buffer_size {
BufferSize::Fixed(v) => v as alsa::pcm::Frames,
BufferSize::Default => {
// These values together represent a moderate latency and wakeup interval.
// Without them, we are at the mercy of the device
hw_params.set_period_time_near(25_000, alsa::ValueOr::Nearest)?;
hw_params.set_buffer_time_near(100_000, alsa::ValueOr::Nearest)?;
// This value represent a moderate latency and wakeup interval.
1024 as alsa::pcm::Frames
}
}
};
hw_params.set_period_size_near(period_size, alsa::ValueOr::Nearest)?;

// We shouldn't fail if the driver isn't happy here.
// `default` pcm sometimes fails here, but there no reason to as we
// provide a direction and 2 is strictly the minimum number of periods.
let _ = hw_params.set_periods(2, alsa::ValueOr::Greater);

pcm_handle.hw_params(&hw_params)?;

Expand Down