Permission denied on "/dev/gpiomem"

golemparts / rppal

A Rust library that provides access to the Raspberry Pi's GPIO, I2C, PWM, SPI and UART peripherals.

MIT License

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Permission denied on "/dev/gpiomem" #164

Open andrewdavidmackenzie opened 2 weeks ago

andrewdavidmackenzie commented 2 weeks ago

This is a new error I am just starting to get:

thread 'tokio-runtime-worker' panicked at src/hardware_subscription.rs:150:22:
called `Result::unwrap()` on an `Err` value: Permission denied: /dev/gpiomem

The only thing I can think of that has changed is that I updated a lot of packages on Pi OS recently.

uname -a
Linux rpi400 6.6.58-v8+ #1809 SMP PREEMPT Wed Oct 23 11:53:53 BST 2024 aarch64 GNU/Linux

I'll try and track down the exact call and add it here.

andrewdavidmackenzie commented 2 weeks ago

Confirmed that running as root avoids the problem.

golemparts commented 2 weeks ago

Make sure /dev/gpiomem has rw permissions set for the gpio group, and the user you're logged in with is part of the gpio group. It looks like you may be running a different distro, which can cause issues. I suggest installing a fresh image of the latest stable Raspberry Pi OS release.

andrewdavidmackenzie commented 2 weeks ago

I'll check those things and get back to you.

It worked fine before on this machine without changing any permissions..., with same distro/install.

All I did is update all packages....maybe that changed something...