Hello, A source code analysis approach by the means of the semantic patch language (Coccinelle software) pointed an implementation detail out for further development considerations. The functions “mtu3_gadget_ep_set_halt” and “mtu3_gadget_ep_set_wedge” check at the beginning if the input parameter “ep” is a null pointer. The error code “-EINVAL” will be returned then. https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/drivers/usb/mtu3/mtu3_gadget.c?id=1590a2e1c681b0991bd42c992cabfd380e0338f2#n371 https://elixir.bootlin.com/linux/v5.7.2/source/drivers/usb/mtu3/mtu3_gadget.c#L371 Can it be nicer to assign the variable “mep” only after a successful check instead of an initialisation before? Regards, Markus