====== VIM3/3L USB Gadget ======

===== Introduction =====

This document mainly introduces USB gadget. You will learn how to configure and enable USB gadget Usage.

<WRAP important >
From version **1.7.5**, USB gadget is enabled by default, no need any setup, you can just skip the overlay and service setup.
</WRAP>

===== System Configuration =====

==== Upgrade System ====

Follow [[/products/sbc/common/configurations/upgrade-system|Upgrade System]] to upgrade system.

==== Configure DTS Overlays ====

<tabbox VIM3/3L with 4.9 kernel>

Take VIM3 as an example.

Open ''/boot/env.txt'':

```shell
sudo vim /boot/env.txt
```

Add ''otg-device'' to overlays node to make USB OTG Device enable:

```
overlays=uart3 pwm_f i2c3 os08a10 --> overlays=uart3 pwm_f i2c3 os08a10 otg-device
```

<WRAP important >
If you have issues, please try the extra steps below:

```shell
wget https://dl.khadas.com/.fixup/libcutils.so -O /tmp/libcutils.so
sudo cp /tmp/libcutils.so /usr/lib
```
</WRAP>

<tabbox VIM3/3L with 5.15 kernel>

Take VIM3 as an example.

Open ''/boot/dtb/amlogic/kvim3.dtb.overlay.env'':

```shell
sudo vim /boot/dtb/amlogic/kvim3.dtb.overlay.env
```

Add ''otg-device'' to overlays node to make USB OTG Device enable:

```
fdt_overlays=otg-device
```

</tabbox>

==== Enable Service ====

```shell
sudo systemctl enable usb-gadget-khadas.service
```

Reboot to effect.

```shell
sync
sudo reboot
```

===== RNDIS Setup IP Address =====

Setup IP address manyally, e.g. setup IP address as ''192.168.35.100''

```shell
sudo ifconfig usb0 192.168.35.100 up
```

Also need to setup the IP address on your PC, e.g. ''192.168.35.110''

Check network connection:

```shell
khadas@Khadas:~$ ping -I usb0 192.168.35.110
PING 192.168.35.1 (192.168.35.1) from 192.168.35.100 usb0: 56(84) bytes of data.
64 bytes from 192.168.35.110: icmp_seq=1 ttl=64 time=0.218 ms
64 bytes from 192.168.35.110: icmp_seq=2 ttl=64 time=0.308 ms
```

===== Usage of ADB =====

Try to access the devices via adb.

```shell
$ adb kill-server
$ adb devices
* daemon not running; starting now at tcp:5037
* daemon started successfully
List of devices attached
363233573350    device

$ adb shell
root@Khadas:/#
root@Khadas:/#
root@Khadas:/#
root@Khadas:/#
root@Khadas:/# ls
bin                dtb.img     lib                proc                srv
bin.usr-is-merged  etc         lib.usr-is-merged  root                sys
boot               home        media              run                 tmp
dev                Image       mnt                sbin                usr
dtb                initrd.img  opt                sbin.usr-is-merged  var
```

===== Troubleshooting =====

If adb not work on windows, you can edit ''/usr/local/bin/usb-gadget'' to comment ''ln -s $F_RNDIS $GADGET/configs/c.1/'' and reboot.

```diff
diff --git a/archives/filesystem/special/VIM-COMMON/usr/local/bin/usb-gadget b/archives/filesystem/special/VIM-COMMON/usr/local/bin/usb-gadget
index 520a9b9a..299569f0 100755
--- a/usr/local/bin/usb-gadget
+++ b/usr/local/bin/usb-gadget
@@ -57,7 +57,7 @@ echo "RNDIS" > $F_RNDIS/os_desc/interface.rndis/compatible_id
 echo "5162001" > $F_RNDIS/os_desc/interface.rndis/sub_compatible_id

 # Bind function to configuration
-ln -s $F_RNDIS $GADGET/configs/c.1/
+#ln -s $F_RNDIS $GADGET/configs/c.1/
 ln -s $GADGET/configs/c.1/ $GADGET/os_desc

 # Enable the Gadget
```