FAQ
Q: I'm getting permission denied errors/exceptions when trying to use my device
A: You can either run as root (or via sudo) which is not recommended, or add a udev rule to properly set permissions.
It is recommended that you go through the udev rules approach, running as root is never a good idea.
Steps
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- NOTE: This is Ubuntu specific but is pretty close to what you need for all systems using udev
Create /etc/udev/rules.d/usb-ftdi.rules with the contents:
#FT2232 Adapter
ACTION=="add", SUBSYSTEM=="usb", ATTRS{idVendor}=="0403", ATTRS{idProduct}=="6015", GROUP:="libftdi", MODE:="0660"
Note that the product and vendor should match what is reported by 'lsusb' for your particular ftdi device. This rule can
be adjusted to allow a series or a range of product values if you have multiple devices with different product values.
Note that the group give, 'libftdi' was added to the system via 'sudo addgroup libftdi' and the user that intends to
use the ftdi device added to this group via 'sudo adduser <username> libftdi'. You can use whichever group you would like
in place of 'libftdi' if your user accounts all belong to that particular group.
There may be a simpler way to reinitialize things but rebooting after these steps will cause the udev rules to
be re-examined and force the user to log-in again which will refresh their group settings.