Hello, I am trying to find out if (and how) it would be possible to use the Cape4All (GitHub - HoerTech-gGmbH/Cape4all: Open Hardware Multichannel Sound Interface for Hearing Aid Research on Beaglebone Black) working on the BBAI-64. Looking at the forum posts, I’m still not sure if the mcasp is supported at all, or if it is “merely” a matter of writing the appropriate magic in the k3-j721e-beagleboneai64.dts file (see the patch in the github project).
The Cape4All basically has 3 ADAU1761 codecs on the mcasp interface, along with an EEPROM, using pins 19, 20, 25, 28, 29, 30 and 31 on P9, the last 4 seeming to be the ones carrying the high-speed data (BCLK ca. 6MHz) thus on the mcasp.
I see that in /opt/source/dtb-5.10-ti-arm64/src/arm64/k3-j721e-common-proc-board.dts there is a definition for mcasp10 (pin assignments and configuration), but in k3-j721e-beagleboneai64.dts all mcasp interfaces are disabled; would it be possible to write appropriate stanzas into k3-j721e-beagleboneai64.dts to get one of the mcasps onto the pins? Or some other pins?
The next problem would of course be the kernel drivers, but one problem at a time… and hopefully the boneblack-audio-extension source could be ported to an up-to-date kernel - but if the mcasp is not useable, there is no point looking at that yet.
Any help would be appreciated, I’m still learning much about device tree specifications and overlays.