android_hardware_UsbRequest.cpp revision 4838e338129e09a37b8c8ad5e44f85ec5cd3aea1 
1/*
2 * Copyright (C) 2010 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#define LOG_TAG "UsbRequestJNI"
18
19#include "utils/Log.h"
20
21#include "jni.h"
22#include "JNIHelp.h"
23#include "android_runtime/AndroidRuntime.h"
24
25#include <usbhost/usbhost.h>
26
27#include <stdio.h>
28
29using namespace android;
30
31static jfieldID field_context;
32
33struct usb_request* get_request_from_object(JNIEnv* env, jobject java_request)
34{
35    return (struct usb_request*)env->GetLongField(java_request, field_context);
36}
37
38// in android_hardware_UsbDeviceConnection.cpp
39extern struct usb_device* get_device_from_object(JNIEnv* env, jobject connection);
40
41static jboolean
42android_hardware_UsbRequest_init(JNIEnv *env, jobject thiz, jobject java_device,
43        jint ep_address, jint ep_attributes, jint ep_max_packet_size, jint ep_interval)
44{
45    ALOGD("init\n");
46
47    struct usb_device* device = get_device_from_object(env, java_device);
48    if (!device) {
49        ALOGE("device null in native_init");
50        return false;
51    }
52
53    // construct an endpoint descriptor from the Java object fields
54    struct usb_endpoint_descriptor desc;
55    desc.bLength = USB_DT_ENDPOINT_SIZE;
56    desc.bDescriptorType = USB_DT_ENDPOINT;
57    desc.bEndpointAddress = ep_address;
58    desc.bmAttributes = ep_attributes;
59    desc.wMaxPacketSize = ep_max_packet_size;
60    desc.bInterval = ep_interval;
61
62    struct usb_request* request = usb_request_new(device, &desc);
63    if (request)
64        env->SetLongField(thiz, field_context, (jlong)request);
65    return (request != NULL);
66}
67
68static void
69android_hardware_UsbRequest_close(JNIEnv *env, jobject thiz)
70{
71    ALOGD("close\n");
72    struct usb_request* request = get_request_from_object(env, thiz);
73    if (request) {
74        usb_request_free(request);
75        env->SetLongField(thiz, field_context, 0);
76    }
77}
78
79static jboolean
80android_hardware_UsbRequest_queue_array(JNIEnv *env, jobject thiz,
81        jbyteArray buffer, jint length, jboolean out)
82{
83    struct usb_request* request = get_request_from_object(env, thiz);
84    if (!request) {
85        ALOGE("request is closed in native_queue");
86        return false;
87    }
88
89    if (buffer && length) {
90        request->buffer = malloc(length);
91        if (!request->buffer)
92            return false;
93        memset(request->buffer, 0, length);
94        if (out) {
95            // copy data from Java buffer to native buffer
96            env->GetByteArrayRegion(buffer, 0, length, (jbyte *)request->buffer);
97        }
98    } else {
99        request->buffer = NULL;
100    }
101    request->buffer_length = length;
102
103    if (usb_request_queue(request)) {
104        if (request->buffer) {
105            // free our buffer if usb_request_queue fails
106            free(request->buffer);
107            request->buffer = NULL;
108        }
109        return false;
110    } else {
111        // save a reference to ourselves so UsbDeviceConnection.waitRequest() can find us
112        request->client_data = (void *)env->NewGlobalRef(thiz);
113        return true;
114    }
115}
116
117static jint
118android_hardware_UsbRequest_dequeue_array(JNIEnv *env, jobject thiz,
119        jbyteArray buffer, jint length, jboolean out)
120{
121    struct usb_request* request = get_request_from_object(env, thiz);
122    if (!request) {
123        ALOGE("request is closed in native_dequeue");
124        return (jint) -1;
125    }
126
127    if (buffer && length && request->buffer && !out) {
128        // copy data from native buffer to Java buffer
129        env->SetByteArrayRegion(buffer, 0, length, (jbyte *)request->buffer);
130    }
131    free(request->buffer);
132    env->DeleteGlobalRef((jobject)request->client_data);
133    return (jint) request->actual_length;
134}
135
136static jboolean
137android_hardware_UsbRequest_queue_direct(JNIEnv *env, jobject thiz,
138        jobject buffer, jint length, jboolean out)
139{
140    struct usb_request* request = get_request_from_object(env, thiz);
141    if (!request) {
142        ALOGE("request is closed in native_queue");
143        return false;
144    }
145
146    if (buffer && length) {
147        request->buffer = env->GetDirectBufferAddress(buffer);
148        if (!request->buffer)
149            return false;
150    } else {
151        request->buffer = NULL;
152    }
153    request->buffer_length = length;
154
155    if (usb_request_queue(request)) {
156        request->buffer = NULL;
157        return false;
158    } else {
159        // save a reference to ourselves so UsbDeviceConnection.waitRequest() can find us
160        // we also need this to make sure our native buffer is not deallocated
161        // while IO is active
162        request->client_data = (void *)env->NewGlobalRef(thiz);
163        return true;
164    }
165}
166
167static jint
168android_hardware_UsbRequest_dequeue_direct(JNIEnv *env, jobject thiz)
169{
170    struct usb_request* request = get_request_from_object(env, thiz);
171    if (!request) {
172        ALOGE("request is closed in native_dequeue");
173        return (jint) -1;
174    }
175    // all we need to do is delete our global ref
176    env->DeleteGlobalRef((jobject)request->client_data);
177    return (jint) request->actual_length;
178}
179
180static jboolean
181android_hardware_UsbRequest_cancel(JNIEnv *env, jobject thiz)
182{
183    struct usb_request* request = get_request_from_object(env, thiz);
184    if (!request) {
185        ALOGE("request is closed in native_cancel");
186        return false;
187    }
188    return (usb_request_cancel(request) == 0);
189}
190
191static JNINativeMethod method_table[] = {
192    {"native_init",             "(Landroid/hardware/usb/UsbDeviceConnection;IIII)Z",
193                                            (void *)android_hardware_UsbRequest_init},
194    {"native_close",            "()V",      (void *)android_hardware_UsbRequest_close},
195    {"native_queue_array",      "([BIZ)Z",  (void *)android_hardware_UsbRequest_queue_array},
196    {"native_dequeue_array",    "([BIZ)I",  (void *)android_hardware_UsbRequest_dequeue_array},
197    {"native_queue_direct",     "(Ljava/nio/ByteBuffer;IZ)Z",
198                                            (void *)android_hardware_UsbRequest_queue_direct},
199    {"native_dequeue_direct",   "()I",      (void *)android_hardware_UsbRequest_dequeue_direct},
200    {"native_cancel",           "()Z",      (void *)android_hardware_UsbRequest_cancel},
201};
202
203int register_android_hardware_UsbRequest(JNIEnv *env)
204{
205    jclass clazz = env->FindClass("android/hardware/usb/UsbRequest");
206    if (clazz == NULL) {
207        ALOGE("Can't find android/hardware/usb/UsbRequest");
208        return -1;
209    }
210    field_context = env->GetFieldID(clazz, "mNativeContext", "J");
211    if (field_context == NULL) {
212        ALOGE("Can't find UsbRequest.mNativeContext");
213        return -1;
214    }
215
216    return AndroidRuntime::registerNativeMethods(env, "android/hardware/usb/UsbRequest",
217            method_table, NELEM(method_table));
218}
219
220