USB: Support for new USB gadget drivers

Change-Id: Id08df50acb873a94f4765a991ee6a6f5b898ddf5
Signed-off-by: Mike Lockwood <lockwood@android.com>

core/java/android/hardware/usb/IUsbManager.aidl

@@ -81,4 +81,13 @@ interface IUsbManager
 
     /* Clears default preferences and permissions for the package */
     void clearDefaults(String packageName);
+
+    /* Sets the current primary USB function. */
+    void setPrimaryFunction(String functions);
+
+    /* Sets the default primary USB function. */
+    void setDefaultFunction(String functions);
+
+    /* Sets the file path for USB mass storage backing file. */
+    void setMassStorageBackingFile(String path);
 }

core/java/android/hardware/usb/UsbManager.java

@@ -22,12 +22,9 @@
 import android.os.Bundle;
 import android.os.ParcelFileDescriptor;
 import android.os.RemoteException;
+import android.os.SystemProperties;
 import android.util.Log;
 
-import java.io.File;
-import java.io.FileInputStream;
-import java.io.FileOutputStream;
-import java.io.IOException;
 import java.util.HashMap;
 
 /**
@@ -50,7 +47,7 @@ public class UsbManager {
      * This is a sticky broadcast for clients that includes USB connected/disconnected state,
      * <ul>
      * <li> {@link #USB_CONNECTED} boolean indicating whether USB is connected or disconnected.
-     * <li> {@link #USB_CONFIGURATION} integer containing current USB configuration
+     * <li> {@link #USB_CONFIGURED} boolean indicating whether USB is configured.
      * currently zero if not configured, one for configured.
      * <li> {@link #USB_FUNCTION_MASS_STORAGE} boolean extra indicating whether the
      * mass storage function is enabled
@@ -128,12 +125,12 @@ public class UsbManager {
     public static final String USB_CONNECTED = "connected";
 
     /**
-     * Integer extra containing currently set USB configuration.
+     * Boolean extra indicating whether USB is configured.
      * Used in extras for the {@link #ACTION_USB_STATE} broadcast.
      *
      * {@hide}
      */
-    public static final String USB_CONFIGURATION = "configuration";
+    public static final String USB_CONFIGURED = "configured";
 
     /**
      * Name of the USB mass storage USB function.
@@ -388,55 +385,70 @@ public void requestPermission(UsbAccessory accessory, PendingIntent pi) {
         }
     }
 
-    private static File getFunctionEnableFile(String function) {
-        return new File("/sys/class/usb_composite/" + function + "/enable");
+    private static boolean propertyContainsFunction(String property, String function) {
+        String functions = SystemProperties.get(property, "");
+        int index = functions.indexOf(function);
+        if (index < 0) return false;
+        if (index > 0 && functions.charAt(index - 1) != ',') return false;
+        int charAfter = index + function.length();
+        if (charAfter < functions.length() && functions.charAt(charAfter) != ',') return false;
+        return true;
     }
 
     /**
-     * Returns true if the specified USB function is supported by the kernel.
-     * Note that a USB function maybe supported but disabled.
+     * Returns true if the specified USB function is currently enabled.
      *
      * @param function name of the USB function
-     * @return true if the USB function is supported.
+     * @return true if the USB function is enabled.
      *
      * {@hide}
      */
-    public static boolean isFunctionSupported(String function) {
-        return getFunctionEnableFile(function).exists();
+    public boolean isFunctionEnabled(String function) {
+        return propertyContainsFunction("sys.usb.config", function);
     }
 
     /**
-     * Returns true if the specified USB function is currently enabled.
+     * Sets the primary USB function.
      *
      * @param function name of the USB function
-     * @return true if the USB function is enabled.
      *
      * {@hide}
      */
-    public static boolean isFunctionEnabled(String function) {
+    public void setPrimaryFunction(String function) {
         try {
-            FileInputStream stream = new FileInputStream(getFunctionEnableFile(function));
-            boolean enabled = (stream.read() == '1');
-            stream.close();
-            return enabled;
-        } catch (IOException e) {
-            return false;
+            mService.setPrimaryFunction(function);
+        } catch (RemoteException e) {
+            Log.e(TAG, "RemoteException in setPrimaryFunction", e);
         }
     }
 
     /**
-     * Enables or disables a USB function.
+     * Sets the default primary USB function.
+     *
+     * @param function name of the USB function
      *
      * {@hide}
      */
-    public static boolean setFunctionEnabled(String function, boolean enable) {
+    public void setDefaultFunction(String function) {
         try {
-            FileOutputStream stream = new FileOutputStream(getFunctionEnableFile(function));
-            stream.write(enable ? '1' : '0');
-            stream.close();
-            return true;
-        } catch (IOException e) {
-            return false;
+            mService.setDefaultFunction(function);
+        } catch (RemoteException e) {
+            Log.e(TAG, "RemoteException in setDefaultFunction", e);
+        }
+    }
+
+    /**
+     * Sets the file path for USB mass storage backing file.
+     *
+     * @param path backing file path
+     *
+     * {@hide}
+     */
+    public void setMassStorageBackingFile(String path) {
+        try {
+            mService.setMassStorageBackingFile(path);
+        } catch (RemoteException e) {
+            Log.e(TAG, "RemoteException in setDefaultFunction", e);
         }
     }
 }

services/java/com/android/server/SystemServer.java

@@ -406,8 +406,8 @@ public void run() {
             }
 
             try {
-                Slog.i(TAG, "USB Observer");
-                // Listen for USB changes
+                Slog.i(TAG, "USB Service");
+                // Manage USB host and device support
                 usb = new UsbService(context);
                 ServiceManager.addService(Context.USB_SERVICE, usb);
             } catch (Throwable e) {