Linux USB Gadget Configfs usage

The use of the Linux 3.0 new USB Gadget CONFIGFS.C driver is as follows:

Mount the Configfs file system:

# mount-t Configfs None/sys/kernel/config

# Cd/sys/kernel/config

# ls

Usb_gadget

# CD Usb_gadget

Create the G1 directory and instantiate a new gadget template:

# mkdir G1

# CD G1

# ls

UDC bdeviceprotocol bMaxPacketSize0 Bcdusb functions Idvendor

Bdeviceclass bdevicesubclass bcddevice configs idproduct strings

Define the VendorID and ProductID of the product

# echo "0XABCD" > Idvendor

# echo "0x1234" > Idproduct

Instantiate English ID:

# mkdir strings/0x409

# ls strings/0x409

Manufacturer Product SerialNumber

Write the developer, product, and serial number string to the kernel:

# echo "0123456789ABCDEF" > Strings/0x409/serialnumber

# echo "Master" > Strings/0x409/manufacturer

# echo "Demo" > Strings/0x409/product

To create a feature instance, it is important to note that if there are multiple instances of a function, the extension must be numbered numerically:

# mkdir FUNCTIONS/ACM. GS0

# mkdir FUNCTIONS/ACM. GS1

# mkdir Functions/ecm.usb0

Create a USB configuration instance:

# mkdir Configs/c.1

# ls Configs/c.1

Maxpower bmattributes Strings

Defines the string used by the configuration descriptor

# mkdir configs/c.1/string/0x409

# ls configs/c.1/strings/0x409/

Configuration

# echo "2XACM+ECM" > Configfs/c.1/strings/0x409/configuration

Bundle feature instances to configuration C.1

# ln-s FUNCTIONS/ACM. GS0 Configs/c.1

# ln-s FUNCTIONS/ACM. GS1 Configs/c.1

# ln-s Functions/ecm.usb0 configs/c.1

Find the available UDC instances for this machine

# ls/sys/class/udc/

Msm_hsusb

Register the gadget driver on a UDC, plug it into a USB cable, and the computer will enumerate the USB devices.

# echo "Msm_hsusb" > UDC