This patchset adds BADD profiles support from the USB Audio Device Class 3.0 spec [1].
BADD profile support is defined as mandatory feature of UAC3-compliant device, it should be implemented as a separate USB configuration.
Notable issue with BADD configuration is that it misses class-specific descriptors (and it's mandatory as per spec), so host should guess them from BADD profile number and parameters of endpoints (type, number of endpoints and max packet size)
This patchset adds support of all known/existing BADD profiles from the UAC3 specification.
It's an alternative implementation comparing to [2], and doesn't build usb descriptors on the host but instead initializes alsa-usb structures with known parameters, so we don't need to keep whole class-specific descriptors in the driver since we anyway need to have BADD-specific logic.
I've picked one Jorge's UAC1 patch-improvement and updated it to v4.17 wich contais recently introduced header's sanity checks.
Remaining part is to add interrupt endpoint support so we will be able to detect jack insertion in the Headset Adapter profile.
This has been tested on ARM and x86-64 machines with custom UAC3 gadget which I'll post later to linux-usb
Comments and testing are welcome.
[1] http://www.usb.org/developers/docs/devclass_docs/USB_Audio_v3.0.zip [2] https://www.spinics.net/lists/alsa-devel/msg71614.html
Jorge Sanjuan (1): ALSA: usb: Only get AudioControl header for UAC1 class.
Ruslan Bilovol (3): ALSA: usb: stream: refactor audio interface parsing include: usb: audio-v3: add BADD-specific values ALSA: usb: add UAC3 BADD profiles support
include/linux/usb/audio-v3.h | 26 ++ sound/usb/card.c | 53 ++-- sound/usb/clock.c | 9 +- sound/usb/mixer.c | 313 +++++++++++++++++++- sound/usb/mixer_maps.c | 65 +++++ sound/usb/stream.c | 678 +++++++++++++++++++++++++------------------ sound/usb/usbaudio.h | 2 + 7 files changed, 836 insertions(+), 310 deletions(-)