#!/bin/bash

GADGET=/sys/kernel/config/usb_gadget/display-pi

SERIAL=`cat /proc/cpuinfo | grep Serial | cut -d ' ' -f 2`
if [ -n "$SERIAL" ]; then
  MAC="fa:${SERIAL:6:2}:${SERIAL:8:2}:${SERIAL:10:2}:${SERIAL:12:2}:${SERIAL:14:2}"
else
  MAC="fa:31:43:14:31:43"
fi

mount -t configfs none /sys/kernel/config
mkdir -p $GADGET
cd $GADGET

echo 0x1d6b > idVendor # Linux Foundation
echo 0x0104 > idProduct # Multifunction Composite Gadget
echo 0x0100 > bcdDevice # v1.0.0
echo 0x0200 > bcdUSB # USB2

echo 0xEF > bDeviceClass
echo 0x02 > bDeviceSubClass
echo 0x01 > bDeviceProtocol

mkdir strings/0x409
echo $SERIAL > strings/0x409/serialnumber
echo "Raspberry Pi" > strings/0x409/manufacturer
echo "Display-Pi USB Device" > strings/0x409/product

mkdir -p functions/acm.usb0    # serial
mkdir -p functions/rndis.usb0  # network
#mkdir -p functions/ecm.usb0
#echo $MAC > functions/ecm.usb0/dev_addr

mkdir -p configs/c.1
echo 250 > configs/c.1/MaxPower
ln -s functions/rndis.usb0 configs/c.1/
ln -s functions/acm.usb0   configs/c.1/
#ln -s functions/ecm.usb0 configs/c.1/

# OS descriptors
# echo 1       > os_desc/use
# echo 0xcd    > os_desc/b_vendor_code
# echo MSFT100 > os_desc/qw_sign
#
# echo RNDIS   > functions/rndis.usb0/os_desc/interface.rndis/compatible_id
# echo 5162001 > functions/rndis.usb0/os_desc/interface.rndis/sub_compatible_id
#
# ln -s configs/c.1 os_desc

# Assuming there is only ever going to be one UDC
udevadm settle -t 5 || :
ls /sys/class/udc > UDC

# systemctl restart networking
# systemctl restart dnsmasq
# systemctl restart sshd