USB Passthrough
Since Dolphin 4.0.2, Dolphin has the ability to passthrough a USB_HID devices designed for user with Wii software. This gives emulated Wii software full control of a hardware device connected to your PC. This is very useful for devices not currently emulated by Dolphin and games that highly depend on extra hardware.
List of Devices and IDs
Tony Hawk Ride Skateboard - VID_1430 PID_0100
Skylanders Wireless Receiver for Wii - VID_1430 PID_0150
Skylanders SwapForce Portal - VID_1430 PID_0150
Skylanders Giants Portal - VID_1430 PID_0150
Rockband 3 Guitar Dongle - Supported - Unverified IDs
Rockband Drumset - Supported - Unverified IDs
EA Active Dongle - Supported - Unverified IDs
EA Active NFL Training Camp Dongle - Supported - Unverified IDs
Wii Speak Module - NOT SUPPORTED
Karaoke Joysound Wii Microphone - NOT SUPPORTED
USB Microphone for Wii - NOT SUPPORTED
Ubisoft Motion Tracking Camera - NOT SUPPORTED
Setting up
Linux
Linux support does not require any special drivers. However, a udev rule must be created to allow access to the devices. Note, the Vender ID and Product ID SHOULD be verified from the device itself before creating the rule.
Paste the following in the /etc/udev/rules.d/52-dolphin.rules file (/lib/udev/rules.d/52-dolphin.rules if making a package):
SUBSYSTEM=="usb", ENV{DEVTYPE}=="usb_device", ATTRS{idVendor}=="XXXX", ATTRS{idProduct}=="XXXX", MODE="0666"
Replace the XXXX with the appropriate Vendor and Product IDs.
Reload udev rules with:
sudo udevadm control --reload-rules
Then reinsert the accessory. When the game is booted it should be able to access the accessory as if it were plugged into a Wii.
If you want to change the rule, links for instructions are available on the libusb FAQ.
Windows
Download and open Zadig, then:
1. In the "Options" menu in Zadig, make sure "List All Devices" is enabled.
2. Look through the devices and find the devic
3. On the right column, select "WinUSB" then click "Replace Driver". Select "Yes" to modify the system driver.
The game will then be able to detect the device on next boot.
macOS
While this can be done in MacOS, there is currently no easy to use guide for it. A modified variant of the Native GameCube Adapter for Wii U guide should work, but what needs to be changed is not immediately apparent.
Android
This feature is not supported on Android.