1. 28 3月, 2017 6 次提交
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      ALSA: firewire-motu: add PCM functionality · dd49b2d1
      Takashi Sakamoto 提交于
      This commit adds PCM functionality to transmit/receive PCM samples.
      
      When one of PCM substreams are running or external clock source is
      selected, current sampling rate is used. Else, the sampling rate is
      changed according to requests from a userspace application.
      
      Available number of samples in a frame of PCM substream is determined at
      open(2) to corresponding PCM character device. Later, packet streaming
      starts by ioctl(2) with SNDRV_PCM_IOCTL_PREPARE. In theory, between them,
      applications can change state of the unit by any write transaction to
      change the number. In this case, this driver may fail packet streaming due
      to wrong data format.
      Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
      Signed-off-by: NTakashi Iwai <tiwai@suse.de>
      dd49b2d1
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      ALSA: firewire-motu: add proc node to show current statuc of clock and packet formats · 4638ec6e
      Takashi Sakamoto 提交于
      This commit adds a proc node for debugging purpose.
      Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
      Signed-off-by: NTakashi Iwai <tiwai@suse.de>
      4638ec6e
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      ALSA: firewire-motu: add stream management functionality · 9b2bb4f2
      Takashi Sakamoto 提交于
      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: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
      Signed-off-by: NTakashi Iwai <tiwai@suse.de>
      9b2bb4f2
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      ALSA: firewire-motu: handle transactions specific for MOTU FireWire models · 2e76701b
      Takashi Sakamoto 提交于
      All models of MOTU FireWire series can be controlled by write transaction
      to addresses in a range from 0x'ffff'f0000'0b00 to 0x'ffff'f000'0cff.
      
      The models support asynchronous notification. This notification has 32 bit
      field data, and is transferred when status of clock changes. Meaning of
      the value is not enough clear yet.
      
      Drivers can register its address to receive the notification. Write
      transaction to 0x'ffff'f000'0b04 registers higher 16 bits of the address.
      Write transaction to 0x'ffff'f0000'0b08 registers the rest of bits. The
      address includes node ID, thus it should be registered every time of bus
      reset.
      Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
      Signed-off-by: NTakashi Iwai <tiwai@suse.de>
      2e76701b
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      ALSA: firewire-motu: add MOTU specific protocol layer · 4641c939
      Takashi Sakamoto 提交于
      MOTU FireWire series uses blocking transmission for AMDTP packet streaming.
      They transmit/receive 8,000 packets per second, to handle the same number
      of data blocks as current sampling transmission frequency. Thus,
      IEC 61883-1/6 packet streaming engine of ALSA firewire stack is available
      for them.
      
      However, the sequence of packet and data blocks includes some quirks.
      Below sample is a sequence of CIP headers of packets received by 828mk2,
      at 44.1kHz of sampling transmission frequency.
      
      quads CIP1        CIP2
      488   0x020F04E8  0x8222FFFF
        8   0x020F04F8  0x8222FFFF
      488   0x020F0400  0x8222FFFF
      488   0x020F0408  0x8222FFFF
        8   0x020F04E8  0x8222FFFF
      488   0x020F04F0  0x8222FFFF
      488   0x020F04F8  0x8222FFFF
      
      The SID (source node ID), DBS (data block size), SPH (source packet header),
      FMT (format ID), FDF (format dependent field) and SYT (time stamp) fields
      are in IEC 61883-1. Especially, FMT is 0x02, FDF is 0x22 and SYT is 0xffff
      to define MOTU specific protocol. In an aspect of dbc field, the value
      represents accumulated number of data blocks included the packet. This
      is against IEC 61883-1, because according to the specification this value
      should be the number of data blocks already transferred.
      
      In ALSA IEC 61883-1/6 engine, this quirk is already supported by
      CIP_DBC_IS_END_EVENT flag, because Echo Audio Fireworks has.
      
      Each data block includes SPH as its first quadlet field, to represent its
      presentation time stamp. Actual value of SPH is compliant to IEC 61883-1;
      lower 25 bits of 32 bits width consists of 13 bits cycle count and 12 bits
      cycle offset.
      
      The rest of each data block consists of 24 bit chunks. All of PCM samples,
      MIDI messages, status and control messages are transferred by the chunks.
      This is similar to '24-bit * 4 Audio Pack' in IEC 61883-6. The position of
      each kind of data depends on generations of each model. The number of
      whole chunks in a data block is a multiple of 4, to consists of
      quadlet-aligned packets.
      
      This commit adds data block processing layer specific for the MOTU
      protocol. The remarkable point is the way to generate SPH header. Time
      stamps for each data blocks are generated by below calculation:
      
       * Using pre-computed table for the number of ticks per event
        *  44,1kHz: (557 + 123/441)
        *  48.0kHz: (512 +   0/441)
        *  88.2kHz: (278 + 282/441)
        *  96.0kHz: (256 +   0/441)
        * 176.4kHz: (139 + 141/441)
        * 192.0kHz: (128 +   0/441)
       * Accumulate the ticks and set the value to SPH for every events.
       * This way makes sense only for blocking transmission because this mode
         transfers fixed number or none of events.
      
      This calculation assumes that each data block has a PCM frame which is
      sampled according to event timing clock. Current packet streaming layer
      has the same assumption.
      
      Although this sequence works fine for MOTU FireWire series at sampling
      transmission frequency based on 48.0kHz, it is not enough at the frequency
      based on 44.1kHz. The units generate choppy noise every few seconds.
      Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
      Signed-off-by: NTakashi Iwai <tiwai@suse.de>
      4641c939
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      ALSA: firewire-motu: add skeleton for Mark of the unicorn (MOTU) FireWire series · 6c3cef48
      Takashi Sakamoto 提交于
      This commit adds an new driver for MOTU FireWire series. In this commit,
      this driver just creates/removes card instance according to bus event.
      More functionalities will be added in following commits.
      Signed-off-by: NTakashi Sakamoto <o-takashi@sakamocchi.jp>
      Signed-off-by: NTakashi Iwai <tiwai@suse.de>
      6c3cef48