Android: Add further documentation to Android README file

Signed-off-by: Hans de Goede <hdegoede@redhat.com>

1 files changed, 90 insertions, 0 deletions

diff --git a/android/README b/android/README
index 3bd110d..1afecc7 100644
--- a/android/README
+++ b/android/README
@@ -1,6 +1,9 @@
 libusb for Android
 ==================
 
+Building:
+---------
+
 To build libusb for Android do the following:
 
  1. Download the latest NDK from:
@@ -22,3 +25,90 @@ Where $ARCH is one of:
     armeabi
     armeabi-v7a
     x86
+
+
+Installing:
+-----------
+
+If you wish to use libusb from native code in own Android application
+then you should add the following line to your Android.mk file:
+
+  include $(PATH_TO_LIBUSB_SRC)/android/jni/libusb.mk
+
+You will then need to add the following lines to the build
+configuration for each native binary which uses libusb:
+
+  LOCAL_C_INCLUDES += $(LIBUSB_ROOT_ABS)
+  LOCAL_SHARED_LIBRARIES += libusb1.0
+
+The Android build system will then correctly include libusb in the
+application package (APK) file, provided ndk-build is invoked before
+the package is built.
+
+
+For a rooted device it is possible to install libusb into the system
+image of a running device:
+
+ 1. Enable ADB on the device.
+
+ 2. Connect the device to a machine running ADB.
+
+ 3. Execute the following commands on the machine
+    running ADB:
+
+    # Make the system partition writable
+    adb shell su -c "mount -o remount,rw /system"
+
+    # Install libusb
+    adb push obj/local/armeabi/libusb1.0.so /sdcard/
+    adb shell su -c "cat > /system/lib/libusb1.0.so < /sdcard/libusb1.0.so"
+    adb shell rm /system/lib/libusb1.0.so
+
+    # Install the samples and tests
+    for B in listdevs fxload xusb sam3u_benchmark hotplugtest stress
+    do
+      adb push "obj/local/armeabi/$B" /sdcard/
+      adb shell su -c "cat > /system/bin/$B < /sdcard/$B"
+      adb shell su -c "chmod 0755 /system/bin/$B"
+      adb shell rm "/sdcard/$B"
+    done
+
+    # Make the system partition read only again
+    adb shell su -c "mount -o remount,ro /system"
+
+    # Run listdevs to
+    adb shell su -c "listdevs"
+
+ 4. If your device only has a single OTG port then ADB can generally
+    be switched to using Wifi with the following commands when connected
+    via USB:
+
+    adb shell netcfg
+    # Note the wifi IP address of the phone
+    adb tcpip 5555
+    # Use the IP address from netcfg
+    adb connect 192.168.1.123:5555
+
+Runtime Permissions:
+--------------------
+
+The default system configuration on most Android device will not allow
+access to USB devices. There are several options for changing this.
+
+If you have control of the system image then you can modify the
+ueventd.rc used in the image to change the permissions on
+/dev/bus/usb/*/*. If using this approach then it is advisable to
+create a new Android permission to protect access to these files.
+It is not advisable to give all applications read and write permissions
+to these files.
+
+For rooted devices the code using libusb could be executed as root
+using the "su" command. An alternative would be to use the "su" command
+to change the permissions on the appropriate /dev/bus/usb/ files.
+
+Users have reported success in using android.hardware.usb.UsbManager
+to request permission to use the UsbDevice and then opening the
+device. The difficulties in this method is that there is no guarantee
+that it will continue to work in the future Android versions, it
+requires invoking Java APIs and running code to match each
+android.hardware.usb.UsbDevice to a libusb_device.