kernel/linux.git - Linux kernel stable tree (mirror)

Age	Commit message (Collapse)	Author	Files	Lines
2017-04-11	ALSA: firewire-motu: add tracepoints for messages for unique protocol	Takashi Sakamoto	1	-0/+50
	MOTU units transfer/receive messages in each data block of their isochronous packet payload. A part of content in the message is cleard for MIDI message transmission, while the rest is unknown yet. Additional features are required to assist users and developers to reveal the details. This commit adds tracepoints for the purpose. The tracepoints are designed for MOTU's protocol version 2 and 3 (Protocol version 1 is not upstreamed yet). In the tracepoints, events are probed to gather first two 24 bit data chunks of each data block. The chunks are formatted into elements of 64 bit array with padding in MSB. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-04-11	ALSA: firewire-motu: add tracepoints for SPH in IEC 61883-1 fashion	Takashi Sakamoto	1	-0/+73
	Unique protocol is used for MOTU FireWire series. In this protocol, data block format is not compliant to AM824 in IEC 61883-1/6. Each of the data block consists of 24 bit data chunks, except for a first quadlet. The quadlet is used for source packet header (SPH) described in IEC 61883-1. The sequence of SPH seems to represent presentation timestamp corresponding to included data. Developers have experienced that invalid sequence brings disorder of units in the series. Unfortunately, current implementation of ALSA IEC 61883-1/6 engine and firewire-motu driver brings periodical noises to the units at sampling transmission frequency based on 44.1 kHz. The engine generates the SPH with even interval and this mechanism seems not to be suitable to the units. Further work is required for this issue and infrastructure is preferable to assist the work. This commit adds tracepoints for the purpose. In the tracepoints, events are probed to gather the SPHs from each data blocks. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>