mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-11-11 12:28:41 +08:00
dfacca3986
This commit takes ALSA fireface driver to perform sequence replay for media clock recovery. The protocol specific to RME Fireface series is not compliant to IEC 61883-1/6 since it has no CIP header, therefore presentation time is not used for media clock recovery. The sequence of the number of data blocks per packet is important. I note that the device skips an isochronous cycle corresponding to an empty packet or a NODATA packet in blocking transmission method of IEC 61883-1/6. For sequence replay, the cycle is handled as receiving an empty packet. Furthermore, it doesn't start packet transmission till receiving any packet. The sequence replay is tested with below models: * Fireface 400 * Fireface 800 * Fireface 802 I note that it is better to initialize Fireface 400 in advance by initialization transaction implemented in snd-fireface-ctl-service of snd-firewire-ctl-services project. You can see whether initialized or not by HOST LED on the device. Unless, the device often stops packet transmission even if session starts. I guess the sequence replay also works well with below models: * Fireface UFX * Fireface UCX Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Link: https://lore.kernel.org/r/20210531025103.17880-7-o-takashi@sakamocchi.jp Signed-off-by: Takashi Iwai <tiwai@suse.de> |
||
|---|---|---|
| .. | ||
| amdtp-ff.c | ||
| ff-hwdep.c | ||
| ff-midi.c | ||
| ff-pcm.c | ||
| ff-proc.c | ||
| ff-protocol-former.c | ||
| ff-protocol-latter.c | ||
| ff-stream.c | ||
| ff-transaction.c | ||
| ff.c | ||
| ff.h | ||
| Makefile | ||