Hi, This is request-for-test (RFT) to the ALSA control service programs for Digidesign Digi 002/003 family and Tascam FireWire series. The programs are available in 'topic/services-for-dg00x-tascam' of below repository, and the RFT is corresponding to Pull Request #1: * https://github.com/alsa-project/snd-firewire-ctl-services/ Background ---------- The models in above family and series are already supported by drivers in ALSA firewire stack for their isochronous packet stream functionality. Although the drivers allow userspace applications to process PCM frames and MIDI messages in the packet streaming, they doesn't support the other functionalities such as volume control since it can be achieved by any usespace applications of Linux firewire subsystem. The service programs added by this patchset are for the supplemental functionality to control the models by asynchronous packet transaction or to process a part of data transferred by the isochronous packet stream. In detail, please read README.rst in the repository[1]. You can see some illustrations. How to build ------------- The project depends on several libraries in below repositories: * glib[2] * alsa-gobject v0.1.0[3] * libhinawa v2.0.0[4] Before building it, please install them with gobject-introspection support. The project is written by Rust programming language[5] and packaged by cargo[6]. To build, just run below commands in the environment to connect to internet: ``` $ git clone https://github.com/alsa-project/snd-firewire-ctl-services.git -b topic/services-for-dg00x-tascam $ cd snd-firewire-ctl-services $ cargo build ``` All of required crates are downloaded automatically, then start build. Executables ----------- The added executables are listed below: * snd-firewire-digi00x-ctl-service * snd-firewire-tascam-ctl-service When running, the programs add and maintain control elements, then enter event loop to dispatch events. Thes elements are visible and manipulable for any userspace applications. The program dispatch any manipulation event for transactions to control actual device. For console model and FE-8 in Tascam FireWire series, the program adds and maintains port in ALSA Sequencer. They have command line options. For all models of Digi 002/003 family, the executable has an option for the numerical ID of sound card. ``` Usage: snd-firewire-digi00x-ctl-service CARD_ID where: CARD_ID: The numerical ID of sound card. ``` For models of Tascam FireWire series except for FE-8, the executable should run with 'snd' as its first option and the numerical ID of sound card as second option. Tascam FE-8 is supported by the service program but not supported by ALSA firewire stack since it doesn't handle isochronous packet streaming. For FE-8, the executable should run with 'fw' as its first option and the numerical ID of firewire character device. ``` Usage: snd-firewire-tascam-ctl-service SUBSYSTEM ID where: SUBSYSTEM: The name of subsystem; 'snd' or 'fw' ID: The numerical ID of sound card or fw character device ``` It's easy to run the executables by cargo, like: ``` $ cargo run --bin snd-firewire-digi00x-ctl-service 2 ``` Receiving SIGTERM signal terminates the event loop, then the program finishes. Access permissions for relevant character devices -------------------------------------------------- The executables manipulate below character devices to dispatch, convert, and emit event from end to end. The '%u' is the numerical number in each subsystem: * ALSA control character device (/dev/snd/controlC%u) * ALSA hwdep character device (/dev/snd/hwC%uD%u) * Linux firewire character device (/dev/fw%u) Additionally, the service program for Tascam FireWire series manipulates ALSA sequencer character device (/dev/snd/seq) to handle events of control surface for console model. Users should pay enough attention to access permission for the above character devices when running the service program. Feedback -------- Any feedback is welcome. For questions, please use mailing list in alsa-devel or alsa-users[7]. For issues, please use service of github.com[8]. Issues ------ The name of control elements are not fixed yet since the convention of name for element set is not clear yet for recording equipment. Users may feel inconvenience to which channel corresponds to which physical port. Furthermore, in the case that element set includes several elements, it's unclear that which element corresponds to which physical port as well. ALSA control core has no feature for the above issues at present. [1] https://github.com/alsa-project/snd-firewire-ctl-services [2] https://gitlab.gnome.org/GNOME/glib [3] https://github.com/alsa-project/alsa-gobject/ [4] https://github.com/alsa-project/libhinawa [5] https://www.rust-lang.org/ [6] https://doc.rust-lang.org/cargo/ [7] https://www.alsa-project.org/wiki/Mailing-lists [8] https://github.com/alsa-project/snd-firewire-ctl-services/issues Regards Takashi Sakamoto
