1. 05 Apr, 2017 3 commits
    • Takashi Sakamoto's avatar
      ALSA: fireface: add support for MIDI functionality · ff2c293e
      Takashi Sakamoto authored
      
      
      In previous commit, fireface driver supports unique transaction mechanism
      for MIDI feature. This commit adds MIDI functionality for userspace
      applications.
      
      As I wrote in a followed commit, user space applications get some
      requirement from this driver. It should not touch a register to which
      units transmit MIDI messages. It should configure a register in which
      MIDI transmission is controlled.
      Signed-off-by: default avatarTakashi Sakamoto <o-takashi@sakamocchi.jp>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      ff2c293e
    • Takashi Sakamoto's avatar
      ALSA: fireface: add transaction support · 19174295
      Takashi Sakamoto authored
      
      
      As long as investigating Fireface 400, MIDI messages are transferred by
      asynchronous communication over IEEE 1394 bus.
      
      Fireface 400 receives MIDI messages by write transactions to two addresses;
      0x'0000'0801'8000 and 0x'0000'0801'9000. Each of two seems to correspond to
      MIDI port 1 and 2.
      
      Fireface 400 transfers MIDI messages by write transactions to certain
      addresses which configured by drivers. The drivers can decide upper 4 byte
      of the addresses by write transactions to 0x'0000'0801'03f4. For the rest
      part of the address, drivers can select from below options:
       * 0x'0000'0000
       * 0x'0000'0080
       * 0x'0000'0100
       * 0x'0000'0180
      
      Selected options are represented in register 0x'0000'0801'051c as bit
      flags. Due to this mechanism, drivers are restricted to use addresses on
      'Memory space' of IEEE 1222, even if transactions to the address have
      some side effects.
      
      This commit adds transaction support for MIDI messaging, based on my
      assumption that the similar mechanism is used on the other protocols. To
      receive asynchronous transactions, the driver allocates a range of address
      in 'Memory space'. I apply a strategy to use 0x'0000'0000 as lower 4 byte
      of the address. When getting failure from Linux FireWire subsystem, this
      driver retries to allocate addresses.
      
      Unfortunately, read transaction to address 0x'0000'0801'051c returns zero
      always, however write transactions have effects to the other features such
      as status of sampling clock. For this reason, this commit delegates a task
      to configure this register to user space applications. The applications
      should set 3rd bit in LSB in little endian order.
      Signed-off-by: default avatarTakashi Sakamoto <o-takashi@sakamocchi.jp>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      19174295
    • Takashi Sakamoto's avatar
      ALSA: fireface: add skeleton for RME Fireface series · 17c4e5ea
      Takashi Sakamoto authored
      
      
      This commit adds a new driver for RME Fireface series. This commit just
      creates/removes card instance according to IEEE 1394 bus event. More
      functions will be added in following commits.
      
      Three types of firmware have released by RME GmbH; for Fireface 400, for
      Fireface 800 and for UCX/802/UFX. It's reasonable that these models use
      different protocol for communication. Currently, I've investigated
      Fireface 400 and nothing others.
      Signed-off-by: default avatarTakashi Sakamoto <o-takashi@sakamocchi.jp>
      Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
      17c4e5ea