DO NOT MERGE: Backport USB accessory support to gingerbread

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

1 files changed, 107 insertions, 2 deletions

diff --git a/services/jni/com_android_server_UsbService.cpp b/services/jni/com_android_server_UsbService.cpp
index dff8665..08a526e 100644
--- a/services/jni/com_android_server_UsbService.cpp
+++ b/services/jni/com_android_server_UsbService.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2009 The Android Open Source Project
+ * Copyright (C) 2010 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,14 +23,119 @@
 #include "utils/Vector.h"
 
 #include <stdio.h>
+#include <asm/byteorder.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <linux/usb/f_accessory.h>
+
+#define DRIVER_NAME "/dev/usb_accessory"
 
 namespace android
 {
 
+static struct file_descriptor_offsets_t
+{
+    jclass mClass;
+    jmethodID mConstructor;
+    jfieldID mDescriptor;
+} gFileDescriptorOffsets;
+
+static struct parcel_file_descriptor_offsets_t
+{
+    jclass mClass;
+    jmethodID mConstructor;
+} gParcelFileDescriptorOffsets;
+
+static void checkAndClearExceptionFromCallback(JNIEnv* env, const char* methodName) {
+    if (env->ExceptionCheck()) {
+        LOGE("An exception was thrown by callback '%s'.", methodName);
+        LOGE_EX(env);
+        env->ExceptionClear();
+    }
+}
+
+static void set_accessory_string(JNIEnv *env, int fd, int cmd, jobjectArray strArray, int index)
+{
+    char buffer[256];
+
+    buffer[0] = 0;
+    int length = ioctl(fd, cmd, buffer);
+    if (buffer[0]) {
+        LOGD("string %d: %s", index, buffer);
+        jstring obj = env->NewStringUTF(buffer);
+        env->SetObjectArrayElement(strArray, index, obj);
+        env->DeleteLocalRef(obj);
+    }
+}
+
+
+static jobjectArray android_server_UsbService_getAccessoryStrings(JNIEnv *env, jobject thiz)
+{
+    LOGD("getAccessoryStrings");
+    int fd = open(DRIVER_NAME, O_RDWR);
+    if (fd < 0) {
+        LOGE("could not open %s", DRIVER_NAME);
+        return NULL;
+    }
+    jclass stringClass = env->FindClass("java/lang/String");
+    jobjectArray strArray = env->NewObjectArray(4, stringClass, NULL);
+    if (!strArray) goto out;
+    set_accessory_string(env, fd, ACCESSORY_GET_STRING_MANUFACTURER, strArray, 0);
+    set_accessory_string(env, fd, ACCESSORY_GET_STRING_MODEL, strArray, 1);
+    set_accessory_string(env, fd, ACCESSORY_GET_STRING_TYPE, strArray, 2);
+    set_accessory_string(env, fd, ACCESSORY_GET_STRING_VERSION, strArray, 3);
+
+out:
+    close(fd);
+    return strArray;
+}
+
+static jobject android_server_UsbService_openAccessory(JNIEnv *env, jobject thiz)
+{
+    int fd = open(DRIVER_NAME, O_RDWR);
+    if (fd < 0) {
+        LOGE("could not open %s", DRIVER_NAME);
+        return NULL;
+    }
+    jobject fileDescriptor = env->NewObject(gFileDescriptorOffsets.mClass,
+        gFileDescriptorOffsets.mConstructor);
+    if (fileDescriptor != NULL) {
+        env->SetIntField(fileDescriptor, gFileDescriptorOffsets.mDescriptor, fd);
+    } else {
+        return NULL;
+    }
+    return env->NewObject(gParcelFileDescriptorOffsets.mClass,
+        gParcelFileDescriptorOffsets.mConstructor, fileDescriptor);
+}
+
+static JNINativeMethod method_table[] = {
+    { "nativeGetAccessoryStrings", "()[Ljava/lang/String;",
+                                  (void*)android_server_UsbService_getAccessoryStrings },
+    { "nativeOpenAccessory","()Landroid/os/ParcelFileDescriptor;",
+                                  (void*)android_server_UsbService_openAccessory },
+};
+
 int register_android_server_UsbService(JNIEnv *env)
 {
+   jclass clazz = env->FindClass("java/io/FileDescriptor");
+    LOG_FATAL_IF(clazz == NULL, "Unable to find class java.io.FileDescriptor");
+    gFileDescriptorOffsets.mClass = (jclass) env->NewGlobalRef(clazz);
+    gFileDescriptorOffsets.mConstructor = env->GetMethodID(clazz, "<init>", "()V");
+    gFileDescriptorOffsets.mDescriptor = env->GetFieldID(clazz, "descriptor", "I");
+    LOG_FATAL_IF(gFileDescriptorOffsets.mDescriptor == NULL,
+                 "Unable to find descriptor field in java.io.FileDescriptor");
+
+   clazz = env->FindClass("android/os/ParcelFileDescriptor");
+    LOG_FATAL_IF(clazz == NULL, "Unable to find class android.os.ParcelFileDescriptor");
+    gParcelFileDescriptorOffsets.mClass = (jclass) env->NewGlobalRef(clazz);
+    gParcelFileDescriptorOffsets.mConstructor = env->GetMethodID(clazz, "<init>", "(Ljava/io/FileDescriptor;)V");
+    LOG_FATAL_IF(gParcelFileDescriptorOffsets.mConstructor == NULL,
+                 "Unable to find constructor for android.os.ParcelFileDescriptor");
 
-    return 0;
+    return jniRegisterNativeMethods(env, "com/android/server/usb/UsbService",
+            method_table, NELEM(method_table));
 }
 
 };