libusb_open在jni android中返回LIBUSB_ERROR_ACCESS

Question

I want to access a usb device from c++ native code in ROOTed android device ( 4.4 )using libusb1.0.22 . First, I call libusb_init successfully and then call libusb_open but get LIBUSB_ERROR_ACCESS error. Why this error is occurring while the device is rooted?

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Answer 1

A

Also on rooted device you MUST permissions! (like linux...)

(1) You MUST to turn off the SELinux (setenforce 0)

(2) You MUST to give file permissions (chmod 666 /dev/bus/usb/*/*), after that your USB connected to the Android device. you can do it with adb over wifi if you have only one USB port. (or to change the device rules to attach USB device node with 666 permissions)

(*) You can use "adb shell run-as" to check your App permissions.

B

(1) You need to check that your device is also work in HOST mode.

(2) You need to check if your USB cable is OTG.