hidapi error: Permission denied

[John-Toohey]

When I run the following command:

$ cargo embed --features v1 --target thumbv6m-none-eabi

I get:

       Error Probe could not be created

             Caused by:
                 0: hidapi error: Permission denied
                 1: hidapi error: Permission denied

Despite having:

$ cat /etc/udev/rules.d/99-microbit.rules

# CMSIS-DAP for microbit
SUBSYSTEM=="usb", ATTR{idVendor}=="0d28", ATTR{idProduct}=="0204", MODE:="666"

I have rebooted several times and even checked the file permission on my device (/dev/bus/usb/001/010):

$ ls /dev/bus/usb/001/010
crw-rw-rw- 189,9 root  4 Dec 07:17 /dev/bus/usb/001/010

My kernel is 6.0.10 and I run archlinux. Any help would be much apreciated.

[sudoBash418]

Not sure if this will fix your issue, but I was facing the same error and fixed it with the following udev rule:

# CMSIS-DAP for microbit
SUBSYSTEMS=="usb", ATTRS{idVendor}=="0d28", ATTRS{idProduct}=="0204", MODE="0660", TAG+="uaccess"

I also needed to use /etc/udev/rules.d/70-microbit.rules, as recommended by the probe-rs docs.

According to the Arch Wiki:

The modern recommended approach for systemd systems is to use a MODE of 660 to let the group use the device, and then attach a TAG named uaccess.

After editing the file, I ran sudo udevadm control --reload and replugged the micro:bit; at which point I was able to run cargo embed without issue.

[Vortoman]

Had the exact same problem, solution worked. Thanks a lot!

[eldruin]

Nice to see that you found a solution.
Could one of you put together a PR adding this to the book?

[bcpeinhardt]

Same fix worked on Ubuntu, with a udevadm trigger instead of replugging in. :)