[alsa-devel] [PATCH] ALSA: firewire-lib: add PCM rules to obsolete PCM constraints based on LCM of SYT_INTERVAL

[Takashi Iwai]

On Sun, 30 Sep 2018 21:11:49 +0200,
Takashi Sakamoto wrote:
> 
> In blocking mode of IEC 61883-1/6, when one isochronous packet includes
> data for events, the data is for the same number of events as
> SYT_INTERVAL decided according to sampling transmission frequency (SFC).
> 
> IEC 61883-1/6 engine of ALSA firewire stack applies constraints of
> period and buffer size of PCM intermediate buffer of PCM substream.
> At present, this constraint is designed to round the size up/down to
> 32 frames. This value comes from the least common multiple (LCM) of
> SYT_INTERVAL. Although this looks to work well, in lower sampling
> rate, applications are not allowed to set size of period quite near
> period time constraint (at present 5 msec per period).
> 
> This commit adds PCM rules for period/buffer size and rate to obsoletes
> the constraints based on LCM.
> 
> Signed-off-by: Takashi Sakamoto <o-takashi at sakamocchi.jp>

Applied, thanks.


Takashi