SensorDevice.cpp revision 667102f6b072582fe497599e0b760f9fc94ceffa 
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#include <stdint.h>
18#include <math.h>
19#include <sys/types.h>
20
21#include <utils/Atomic.h>
22#include <utils/Errors.h>
23#include <utils/Singleton.h>
24
25#include <binder/BinderService.h>
26#include <binder/Parcel.h>
27#include <binder/IServiceManager.h>
28
29#include <hardware/sensors.h>
30
31#include "SensorDevice.h"
32#include "SensorService.h"
33
34namespace android {
35// ---------------------------------------------------------------------------
36class BatteryService : public Singleton<BatteryService> {
37    static const int TRANSACTION_noteStartSensor = IBinder::FIRST_CALL_TRANSACTION + 3;
38    static const int TRANSACTION_noteStopSensor = IBinder::FIRST_CALL_TRANSACTION + 4;
39    static const String16 DESCRIPTOR;
40
41    friend class Singleton<BatteryService>;
42    sp<IBinder> mBatteryStatService;
43
44    BatteryService() {
45        const sp<IServiceManager> sm(defaultServiceManager());
46        if (sm != NULL) {
47            const String16 name("batteryinfo");
48            mBatteryStatService = sm->getService(name);
49        }
50    }
51
52    status_t noteStartSensor(int uid, int handle) {
53        Parcel data, reply;
54        data.writeInterfaceToken(DESCRIPTOR);
55        data.writeInt32(uid);
56        data.writeInt32(handle);
57        status_t err = mBatteryStatService->transact(
58                TRANSACTION_noteStartSensor, data, &reply, 0);
59        err = reply.readExceptionCode();
60        return err;
61    }
62
63    status_t noteStopSensor(int uid, int handle) {
64        Parcel data, reply;
65        data.writeInterfaceToken(DESCRIPTOR);
66        data.writeInt32(uid);
67        data.writeInt32(handle);
68        status_t err = mBatteryStatService->transact(
69                TRANSACTION_noteStopSensor, data, &reply, 0);
70        err = reply.readExceptionCode();
71        return err;
72    }
73
74public:
75    void enableSensor(int handle) {
76        if (mBatteryStatService != 0) {
77            int uid = IPCThreadState::self()->getCallingUid();
78            int64_t identity = IPCThreadState::self()->clearCallingIdentity();
79            noteStartSensor(uid, handle);
80            IPCThreadState::self()->restoreCallingIdentity(identity);
81        }
82    }
83    void disableSensor(int handle) {
84        if (mBatteryStatService != 0) {
85            int uid = IPCThreadState::self()->getCallingUid();
86            int64_t identity = IPCThreadState::self()->clearCallingIdentity();
87            noteStopSensor(uid, handle);
88            IPCThreadState::self()->restoreCallingIdentity(identity);
89        }
90    }
91};
92
93const String16 BatteryService::DESCRIPTOR("com.android.internal.app.IBatteryStats");
94
95ANDROID_SINGLETON_STATIC_INSTANCE(BatteryService)
96
97// ---------------------------------------------------------------------------
98
99ANDROID_SINGLETON_STATIC_INSTANCE(SensorDevice)
100
101SensorDevice::SensorDevice()
102    :  mSensorDevice(0),
103       mSensorModule(0)
104{
105    status_t err = hw_get_module(SENSORS_HARDWARE_MODULE_ID,
106            (hw_module_t const**)&mSensorModule);
107
108    LOGE_IF(err, "couldn't load %s module (%s)",
109            SENSORS_HARDWARE_MODULE_ID, strerror(-err));
110
111    if (mSensorModule) {
112        err = sensors_open(&mSensorModule->common, &mSensorDevice);
113
114        LOGE_IF(err, "couldn't open device for module %s (%s)",
115                SENSORS_HARDWARE_MODULE_ID, strerror(-err));
116
117        if (mSensorDevice) {
118            sensor_t const* list;
119            ssize_t count = mSensorModule->get_sensors_list(mSensorModule, &list);
120            mActivationCount.setCapacity(count);
121            Info model;
122            for (size_t i=0 ; i<size_t(count) ; i++) {
123                mActivationCount.add(list[i].handle, model);
124                mSensorDevice->activate(mSensorDevice, list[i].handle, 0);
125            }
126        }
127    }
128}
129
130void SensorDevice::dump(String8& result, char* buffer, size_t SIZE)
131{
132    if (!mSensorModule) return;
133    sensor_t const* list;
134    ssize_t count = mSensorModule->get_sensors_list(mSensorModule, &list);
135
136    snprintf(buffer, SIZE, "%d h/w sensors:\n", int(count));
137    result.append(buffer);
138
139    Mutex::Autolock _l(mLock);
140    for (size_t i=0 ; i<size_t(count) ; i++) {
141        const Info& info = mActivationCount.valueFor(list[i].handle);
142        snprintf(buffer, SIZE, "handle=0x%08x, active-count=%d, rates(ms)={ ",
143                list[i].handle,
144                info.rates.size());
145        result.append(buffer);
146        for (size_t j=0 ; j<info.rates.size() ; j++) {
147            snprintf(buffer, SIZE, "%4.1f%s",
148                    info.rates.valueAt(j) / 1e6f,
149                    j<info.rates.size()-1 ? ", " : "");
150            result.append(buffer);
151        }
152        snprintf(buffer, SIZE, " }, selected=%4.1f ms\n",  info.delay / 1e6f);
153        result.append(buffer);
154    }
155}
156
157ssize_t SensorDevice::getSensorList(sensor_t const** list) {
158    if (!mSensorModule) return NO_INIT;
159    ssize_t count = mSensorModule->get_sensors_list(mSensorModule, list);
160    return count;
161}
162
163status_t SensorDevice::initCheck() const {
164    return mSensorDevice && mSensorModule ? NO_ERROR : NO_INIT;
165}
166
167ssize_t SensorDevice::poll(sensors_event_t* buffer, size_t count) {
168    if (!mSensorDevice) return NO_INIT;
169    return mSensorDevice->poll(mSensorDevice, buffer, count);
170}
171
172status_t SensorDevice::activate(void* ident, int handle, int enabled)
173{
174    if (!mSensorDevice) return NO_INIT;
175    status_t err(NO_ERROR);
176    bool actuateHardware = false;
177
178    Info& info( mActivationCount.editValueFor(handle) );
179
180
181    LOGD_IF(DEBUG_CONNECTIONS,
182            "SensorDevice::activate: ident=%p, handle=0x%08x, enabled=%d, count=%d",
183            ident, handle, enabled, info.rates.size());
184
185    if (enabled) {
186        Mutex::Autolock _l(mLock);
187        LOGD_IF(DEBUG_CONNECTIONS, "... index=%ld",
188                info.rates.indexOfKey(ident));
189
190        if (info.rates.indexOfKey(ident) < 0) {
191            info.rates.add(ident, DEFAULT_EVENTS_PERIOD);
192            if (info.rates.size() == 1) {
193                actuateHardware = true;
194            }
195        } else {
196            // sensor was already activated for this ident
197        }
198    } else {
199        Mutex::Autolock _l(mLock);
200        LOGD_IF(DEBUG_CONNECTIONS, "... index=%ld",
201                info.rates.indexOfKey(ident));
202
203        ssize_t idx = info.rates.removeItem(ident);
204        if (idx >= 0) {
205            if (info.rates.size() == 0) {
206                actuateHardware = true;
207            }
208        } else {
209            // sensor wasn't enabled for this ident
210        }
211    }
212
213    if (actuateHardware) {
214        LOGD_IF(DEBUG_CONNECTIONS, "\t>>> actuating h/w");
215
216        err = mSensorDevice->activate(mSensorDevice, handle, enabled);
217        if (enabled) {
218            LOGE_IF(err, "Error activating sensor %d (%s)", handle, strerror(-err));
219            if (err == 0) {
220                BatteryService::getInstance().enableSensor(handle);
221            }
222        } else {
223            if (err == 0) {
224                BatteryService::getInstance().disableSensor(handle);
225            }
226        }
227    }
228
229    { // scope for the lock
230        Mutex::Autolock _l(mLock);
231        nsecs_t ns = info.selectDelay();
232        mSensorDevice->setDelay(mSensorDevice, handle, ns);
233    }
234
235    return err;
236}
237
238status_t SensorDevice::setDelay(void* ident, int handle, int64_t ns)
239{
240    if (!mSensorDevice) return NO_INIT;
241    Mutex::Autolock _l(mLock);
242    Info& info( mActivationCount.editValueFor(handle) );
243    status_t err = info.setDelayForIdent(ident, ns);
244    if (err < 0) return err;
245    ns = info.selectDelay();
246    return mSensorDevice->setDelay(mSensorDevice, handle, ns);
247}
248
249// ---------------------------------------------------------------------------
250
251status_t SensorDevice::Info::setDelayForIdent(void* ident, int64_t ns)
252{
253    ssize_t index = rates.indexOfKey(ident);
254    if (index < 0) {
255        LOGE("Info::setDelayForIdent(ident=%p, ns=%lld) failed (%s)",
256                ident, ns, strerror(-index));
257        return BAD_INDEX;
258    }
259    rates.editValueAt(index) = ns;
260    return NO_ERROR;
261}
262
263nsecs_t SensorDevice::Info::selectDelay()
264{
265    nsecs_t ns = rates.valueAt(0);
266    for (size_t i=1 ; i<rates.size() ; i++) {
267        nsecs_t cur = rates.valueAt(i);
268        if (cur < ns) {
269            ns = cur;
270        }
271    }
272    delay = ns;
273    return ns;
274}
275
276// ---------------------------------------------------------------------------
277}; // namespace android
278
279