grouper: enable USB OTG storage

Change-Id: I7b97c2cf58e2d18bb170b274e1e4ce35adc3df87
diff --git a/fstab.grouper b/fstab.grouper
index c1bddbc..ff1e468 100644
--- a/fstab.grouper
+++ b/fstab.grouper
@@ -12,3 +12,4 @@
 /dev/block/platform/sdhci-tegra.3/by-name/SOS           /recovery           emmc      defaults                                                      defaults
 /dev/block/platform/sdhci-tegra.3/by-name/USP           /staging            emmc      defaults                                                      defaults
 
+/devices/platform/tegra-ehci                                /storage/usbdisk    vfat      defaults          voldmanaged=usbdisk:auto
diff --git a/init.grouper.rc b/init.grouper.rc
index b28ed51..3d77a01 100644
--- a/init.grouper.rc
+++ b/init.grouper.rc
@@ -18,6 +18,11 @@
     symlink /storage/emulated/legacy /storage/sdcard0
     symlink /mnt/shell/emulated/0 /storage/emulated/legacy
 
+    # create directory for mounting usb drives
+    mkdir /storage/usbdisk 0666 system system
+    symlink /storage/usbdisk /mnt/usbdisk
+    symlink /mnt/usbdisk /usbdisk
+
 on early-boot
     write /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor interactive
     write /sys/devices/system/cpu/cpu1/cpufreq/scaling_governor interactive
diff --git a/overlay/frameworks/base/core/res/res/xml/storage_list.xml b/overlay/frameworks/base/core/res/res/xml/storage_list.xml
index 344fe1e..a6939fb 100644
--- a/overlay/frameworks/base/core/res/res/xml/storage_list.xml
+++ b/overlay/frameworks/base/core/res/res/xml/storage_list.xml
@@ -21,8 +21,14 @@
 
 <StorageList xmlns:android="http://schemas.android.com/apk/res/android">
     <!-- internal emulated storage -->
-    <storage
-        android:storageDescription="@string/storage_internal"
-        android:emulated="true"
-        android:mtpReserve="100" />
+    <storage android:mountPoint="/storage/sdcard0"
+            android:storageDescription="@string/storage_internal"
+            android:primary="true"
+            android:emulated="true"
+            android:mtpReserve="100" />
+    <!-- external USB OTG storage -->
+    <storage android:mountPoint="/storage/usbdisk"
+            android:storageDescription="@string/storage_usb"
+            android:primary="false"
+            android:removable="true" />
 </StorageList>
diff --git a/vold.fstab b/vold.fstab
index 41e9f31..972cbd1 100644
--- a/vold.fstab
+++ b/vold.fstab
@@ -11,3 +11,4 @@
 ######################
 
 # Mounts the first usable partition of the specified device
+dev_mount usbdisk /storage/usbdisk auto /devices/platform/tegra-ehci