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path: root/sound/firewire/motu/motu-stream.c
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2017-09-12ALSA: firewire: Use common error handling code in snd_motu_stream_start_duplex()Markus Elfring
Add a jump target so that a bit of exception handling can be better reused at the end of this function. This issue was detected by using the Coccinelle software. Signed-off-by: Markus Elfring <elfring@users.sourceforge.net> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-08-21ALSA: firewire-motu: add specification flag for position of flag for MIDI ↵Takashi Sakamoto
messages In protocols of MOTU FireWire series, when transferring MIDI messages, transmitter set existence flag to one byte on first several quadlets. The position differs depending on protocols and models, however two cases are confirmed; in 5th byte and 8th byte from MSB side. This commit adds a series of specification flag to describe them. When the existence flag is in the 5th byte, SND_MOTU_SPEC_[R|T]X_MIDI_2ND_Q is used. Else, another set of the flag is used. Here, '_Q' means quadlet. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-28ALSA: firewire-motu: add hwdep interfaceTakashi Sakamoto
This commit adds hwdep interface so as the other sound drivers for units on IEEE 1394 bus have. This interface is designed for mixer/control applications. By using this interface, an application can get information about firewire node, can lock/unlock kernel streaming and can get notification at starting/stopping kernel streaming. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-28ALSA: firewire-motu: add MIDI functionalityTakashi Sakamoto
In MOTU FireWire series, MIDI messages are multiplexed to isochronous packets as well as PCM frames, while the way is different from the one in IEC 61883-6. MIDI messages are put into a certain position in message chunks. One data block can includes one byte of the MIDI messages. When data block includes a MIDI byte, the block has a flag in a certain position of the message chunk. These positions are unique depending on protocols. Once a data block includes a MIDI byte, some following data blocks includes no MIDI bytes. Next MIDI byte appears on a data block corresponding to next cycle of physical MIDI bus. This seems to avoid buffer overflow caused by bandwidth differences between IEEE 1394 bus and physical MIDI bus. This commit adds MIDI functionality to transfer/receive MIDI messages. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>
2017-03-28ALSA: firewire-motu: add stream management functionalityTakashi Sakamoto
This commit adds a functionality to manage packet streaming for MOTU FireWire series. The streaming is not controlled by CMP, thus against IEC 61883-1. Write transaction to certain addresses start/stop packet streaming. Transactions to 0x'ffff'f000'0b00 results in isochronous channel number for both directions and starting/stopping transmission of packets. The isochronous channel number is represented in 6 bit field, thus units can identify the channels up to 64, as IEEE 1394 bus specification described. Transactions to 0x'ffff'f000'0b10 results in packet format for both directions and transmission speed. When each of data block includes fixed part of data chunks only, corresponding flags stand. When bus reset occurs, the units continue to transmit packets with non-contiguous data block counter. This causes discontinuity detection in packet streaming engine and ALSA PCM applications receives EPIPE from any I/O operation. In this case, typical applications manage to recover corresponding PCM substream. This behaviour is kicked much earlier than callback of bus reset handler by Linux FireWire subsystem, therefore status of packet streaming is not changed in the handler. Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp> Signed-off-by: Takashi Iwai <tiwai@suse.de>