Android USB host and hidden devices
android, api, host, usb
Solution
To enable USB host API support you should add a file named android.hardware.usb.host.xml and containing the following lines:
<permissions>
<feature name="android.hardware.usb.host"/>
</permissions>
into folder
/system/etc/permissions
in that folder find file named
handheld_core_hardware.xml or tablet_core_hardware.xml
and add
<feature name="android.hardware.usb.host" />
into `<permissions>` section.
Reboot your device. Usb host api should work.
Tested on CUBE U30GT with android 4.
Problem
I am developing an Android application in which I have to communicate to an USB device. I tried to use standart google API in my app, but list of devices is allways empty. Same things if i use USB device info with google api. List of devices searched by google api is empty, lsusb gives following results: ``` Bus 001 Device 001: ID 1d6b:0001 Bus 002 Device 001: ID 1d6b:0002 Bus 003 Device 001: ID 1d6b:0001 Bus 002 Device 002: ID 2226:0014 ``` my device is 2226:0014 log of eclipse: ``` I/USB3G(92): event { 'add', '/devices/platform/sw-ehci.1/usb2/2-1', 'usb', '', 189, 133 } I/USB3G(92): path : '/sys/devices/platform/sw-ehci.1/usb2/2-1' I/USB3G(92): VID :size 5,vid_path '/sys/devices/platform/sw-ehci.1/usb2/2-1/idVendor',VID '2226 I/USB3G(92): '. I/USB3G(92): PID :size 5,Pid_path '/sys/devices/platform/sw-ehci.1/usb2/2-1/idProduct',PID '0014 I/USB3G(92): '. I/USB3G(92): cmd=/system/etc/usb_modeswitch.sh /system/etc/usb_modeswitch.d/2226_0014 &, I/USB3G(92): excute ret : 0,err:No such file or directory ``` If i plug in devices like rs232 adapters, bluetooth dongle, nothing happens,and there is no any result from API and lsusb. Prtocol of a device is based on ezusb library. Android v.: 4.0.3 kernel v.: 3.0.8 firmware build: crane_evb-eng 4.0.3 IMLK74k 20120330 Is there are any way to access hidden USB devices via API, or should i implement support of this device by writing driver and patching it into the firmware? UPDATE: even if i create info file in *system/etc/usb_modeswitch.d/* with name 2226_0014 containing ``` DefaultVendor= 0x2226 DefaultProduct=0x0014 TargetVendor= 0x2226 TargetProductList="0014" MessageEndpoint="0x00" NeedResponse=1 CheckSuccess=20 ``` i get the same error: "No such file or directory"