Copy the 99-cmsis-dap.rules file in this directory to your udev configuration directory and restart udev:

sudo cp 99-cmsis-dap.rules /etc/udev/rules.d
sudo udevadm control --reload

This rules file permits user access to all CMSIS-DAP based probes; if you already have OpenOCD installed system-wide this rule may already be in place, or you can install custom rules for only a specific probe.

For use with CMSIS-DAP v1 probes, no additional driver installation is necessary, as the default HID drivers should work.

Most CMSIS-DAPv2 interfaces should use WinUSB drivers and not require any additional installation, but this is not always set up correctly by each probe. If your probe does not work in v2 mode, first check it does in fact support v2 (many do not) and check for any vendor-supplied drivers. If these do not work, try using Zadig to set up a driver. Download and run the Zadig executable, select your probe's CMSIS-DAPv2 interface in the dropdown, and click Install Driver, and click the Replace Driver button. This will install a default WinUSB driver for the probe's VID:PID combination, allowing ECPDAP to use the device.

Install libusb-compat via Homebrew:

brew install libusb-compat 

Confirmed working under MacOS 11.4 Big Sur