Hi,
In Linux firewire subsystem, the series of timestamp for each packets is passed as argument to callback of IT context. The timestamp comes from descriptor of 1394 OHCI IT context and represents the cycle to process queued packet.
In current implementation of ALSA IEC 61883-1/6 packet streaming engine, the timestamp comes from calculation with the last packet to generate the callback, thus it's not per-packet information.
For simplicity, this patchset uses the header to compute the cycle for packet to be going to be queued. Additionally, this patchset adds some minor refactoring.
Takashi Sakamoto (4): ALSA: firewire-lib: use union for directional parameters ALSA: firewire-lib: add helper function to cancel context inner callback handler ALSA: firewire-lib: obsolete macro for header of IT context ALSA: firewire-lib: use IT context header to compute cycle count for scheduling packet
sound/firewire/amdtp-am824.c | 2 +- sound/firewire/amdtp-stream.c | 181 +++++++++++--------- sound/firewire/amdtp-stream.h | 35 ++-- sound/firewire/digi00x/amdtp-dot.c | 2 +- sound/firewire/fireworks/fireworks_stream.c | 4 +- sound/firewire/motu/amdtp-motu.c | 2 +- sound/firewire/tascam/amdtp-tascam.c | 2 +- 7 files changed, 135 insertions(+), 93 deletions(-)