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| author | Takashi Sakamoto <o-takashi@sakamocchi.jp> | 2017-03-22 15:30:20 +0300 |
|---|---|---|
| committer | Takashi Iwai <tiwai@suse.de> | 2017-03-28 13:33:34 +0300 |
| commit | 9b2bb4f2f4a213a768a84fa25c14be54844f5bb6 (patch) | |
| tree | e21d07ea7d4fce43739fd0236b95e41f9e962330 /sound/firewire/motu/motu.h | |
| parent | 2e76701bbb1fbe55f7d8538ae7f6869070eb3446 (diff) | |
| download | linux-9b2bb4f2f4a213a768a84fa25c14be54844f5bb6.tar.xz | |
ALSA: firewire-motu: add stream management functionality
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>
Diffstat (limited to 'sound/firewire/motu/motu.h')
| -rw-r--r-- | sound/firewire/motu/motu.h | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/sound/firewire/motu/motu.h b/sound/firewire/motu/motu.h index ed1d779c0dcc..90d274167a4a 100644 --- a/sound/firewire/motu/motu.h +++ b/sound/firewire/motu/motu.h @@ -23,6 +23,7 @@ #include "../lib.h" #include "../amdtp-stream.h" +#include "../iso-resources.h" struct snd_motu_packet_format { unsigned char pcm_byte_offset; @@ -48,6 +49,10 @@ struct snd_motu { struct snd_motu_packet_format rx_packet_formats; struct amdtp_stream tx_stream; struct amdtp_stream rx_stream; + struct fw_iso_resources tx_resources; + struct fw_iso_resources rx_resources; + unsigned int capture_substreams; + unsigned int playback_substreams; /* For notification. */ struct fw_address_handler async_handler; @@ -118,4 +123,9 @@ int snd_motu_transaction_write(struct snd_motu *motu, u32 offset, __be32 *reg, int snd_motu_transaction_register(struct snd_motu *motu); int snd_motu_transaction_reregister(struct snd_motu *motu); void snd_motu_transaction_unregister(struct snd_motu *motu); + +int snd_motu_stream_init_duplex(struct snd_motu *motu); +void snd_motu_stream_destroy_duplex(struct snd_motu *motu); +int snd_motu_stream_start_duplex(struct snd_motu *motu, unsigned int rate); +void snd_motu_stream_stop_duplex(struct snd_motu *motu); #endif |