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/openbmc/linux/sound/firewire/motu/ |
H A D | amdtp-motu-trace.h | 17909c1b Sun Apr 09 07:33:28 CDT 2017 Takashi Sakamoto <o-takashi@sakamocchi.jp> ALSA: firewire-motu: add tracepoints for SPH in IEC 61883-1 fashion
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> 17909c1b Sun Apr 09 07:33:28 CDT 2017 Takashi Sakamoto <o-takashi@sakamocchi.jp> ALSA: firewire-motu: add tracepoints for SPH in IEC 61883-1 fashion 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>
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H A D | Makefile | 17909c1b Sun Apr 09 07:33:28 CDT 2017 Takashi Sakamoto <o-takashi@sakamocchi.jp> ALSA: firewire-motu: add tracepoints for SPH in IEC 61883-1 fashion
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> 17909c1b Sun Apr 09 07:33:28 CDT 2017 Takashi Sakamoto <o-takashi@sakamocchi.jp> ALSA: firewire-motu: add tracepoints for SPH in IEC 61883-1 fashion 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>
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H A D | amdtp-motu.c | 17909c1b Sun Apr 09 07:33:28 CDT 2017 Takashi Sakamoto <o-takashi@sakamocchi.jp> ALSA: firewire-motu: add tracepoints for SPH in IEC 61883-1 fashion
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> 17909c1b Sun Apr 09 07:33:28 CDT 2017 Takashi Sakamoto <o-takashi@sakamocchi.jp> ALSA: firewire-motu: add tracepoints for SPH in IEC 61883-1 fashion 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>
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