]> git.baikalelectronics.ru Git - kernel.git/commit
ALSA: firewire-lib: add a member into AMDTP domain for events per period
authorTakashi Sakamoto <o-takashi@sakamocchi.jp>
Mon, 7 Oct 2019 11:05:16 +0000 (20:05 +0900)
committerTakashi Iwai <tiwai@suse.de>
Thu, 17 Oct 2019 10:02:40 +0000 (12:02 +0200)
commit7109545a5e39f730ed5837b840b5c4b77790a9a7
tree983112529c34bf6f0adac007fe5ebff8de7a47b6
parentcfd17dd6ba61be3c010d08481210306c349d383e
ALSA: firewire-lib: add a member into AMDTP domain for events per period

In IEC 61883-6, it's called as 'event' what has presentation time
represented by timestamp in CIP header. Although the ratio of the number
of event against the number of data block is different depending on
event data type represented by the specific field in CIP header, it's
just one in the most cases supported by ALSA IEC 61883-1/6 engine.

In 1394 OHCI specification, applications can schedule hardware IRQ
by configuring descriptor with IRQ flag for packet against each
isochronous cycle. For future commit, I use the hardware IRQ for
isoc IT context to acknowledge the elapse of PCM period for both
playback/capture directions on AMDTP streams in the same domain.

This commit is a preparation for the above idea. This commit adds
a member into AMDTP domain structure to record the number of PCM frames.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Link: https://lore.kernel.org/r/20191007110532.30270-2-o-takashi@sakamocchi.jp
Signed-off-by: Takashi Iwai <tiwai@suse.de>
sound/firewire/amdtp-stream.c
sound/firewire/amdtp-stream.h