Force feedback wheel support – status 2

While searching for some HID parser code to parse HID input reports from Logitech wheels, I found an interesting driver that can do this job: UHID. It was written to allow connecting a userspace-managed device to the HID core driver of Linux. My first idea was to create a device with UHID, logically connected to the USB bus, with the same name and USB ids, and the fixed HID report from the Linux kernel. But using the same bus and the same USB ids makes the HID core driver load specific drivers (hid-lg, hid-lg4ff). The userspace-managed device I want to create is an input device only, since I’m already managing the HID OUT interrupt endpoint with libusb. The solution is to connect the device to the virtual bus. The last thing to care about is to set the same calibration parameters as the kernel does.