android+静音与马达振动流程.doc

android 静音与马达振动流程
1,设置静音和振动
静音和振动都属于来电后的动作.所以在设置静音和振动时都只是设置一些标识,并往数据库写入相应标识.

文件：packages/apps/settings/src/com/android/settings/SoundAndDisplaySettings.java

private CheckBoxPreference mSilent;

private CheckBoxPreference mVibrate;

private void setRingerMode(boolean silent, boolean vibrate) {

if (silent) {

mAudioManager.setRingerMode(vibrate ? AudioManager.RINGER_MODE_VIBRATE :

AudioManager.RINGER_MODE_SILENT);

} else {

mAudioManager.setRingerMode(AudioManager.RINGER_MODE_NORMAL);

mAudioManager.setVibrateSetting(AudioManager.VIBRATE_TYPE_RINGER,

vibrate ? AudioManager.VIBRATE_SETTING_ON

: AudioManager.VIBRATE_SETTING_OFF);

}

}

public boolean onPreferenceTreeClick(PreferenceScreen preferenceScreen, Preference preference) {

if (preference == mSilent || preference == mVibrate) {

setRingerMode(mSilent.isChecked(), mVibrate.isChecked());

if (preference == mSilent) updateState(false);

}

...

静音和振动是复选框按钮,两个中有一个发生变化时调用setRingerMode对状态进行设置;如下状态描术:

RINGER_MODE_SILENT 静音,且无振动

RINGER_MODE_VIBRATE 静音,但有振动

RINGER_MODE_NORMAL 正常声音,振动开关由setVibrateSetting决定.

铃响模式的设置是通过mAudioManager(音频管理器)来实现的.

2 音频管理器服务
mAudioManager所在服务如下:

文件: frameworks/base/media/java/android/media/AudioManager.java

public static final int RINGER_MODE_SILENT = 0;

public static final int RINGER_MODE_VIBRATE = 1;

public static final int RINGER_MODE_NORMAL = 2;

public void setRingerMode(int ringerMode) {

IAudioService service = getService();

try {

service.setRingerMode(ringerMode);

} catch (RemoteException e) {

Log.e(TAG, "Dead object in setRingerMode", e);

}

}

将铃响模式值传给音频接口服务IaudioService

public static final int VIBRATE_TYPE_RINGER = 0;

public static final int VIBRATE_TYPE_NOTIFICATION = 1;

public static final int VIBRATE_SETTING_OFF = 0;

public static final int VIBRATE_SETTING_ON = 1;

public static final int VIBRATE_SETTING_ONLY_SILENT = 2;

public void setVibrateSetting(int vibrateTyp , int vibrateSetting) {

IAudioService service = getService();

try {

service.setVibrateSetting(vibrateType, vibrateSetting);

} catch (RemoteException e) {

Log.e(TAG, "Dead object in setVibrateSetting", e);

}

}

将振动类型和振动设置传给音频接口服务IaudioService,IaudioService的定义如下:

frameworks/base/media/java/android/media/IAudioService.aidl

frameworks/base/media/java/android/media/AudioService.java

文件: frameworks/base/media/java/android/media/AudioService.java

文件: frameworks/base/core/java/android/provider/Settings.java

public void setRingerMode(int ringerMode) {

synchronized (mSettingsLock) {

if (ringerMode != mRingerMode) {

setRingerModeInt(ringerMode, true);

// Send sticky broadcast

broadcastRingerMode();

}

}

}

将对应模式下的音量写入数据库,并将该模式广播.

public void setVibrateSetting(int vibrateType, int vibrateSetting) {

mVibrateSetting = getValueForVibrateSetting(mVibrateSetting, vibrateType, vibrateSetting);

// Broadcast change

broadcastVibrateSetting(vibrateType);

// Post message to set ringer mode (it in turn will post a message

// to persist)

sendMsg(mAudioHandler, MSG_PERSIST_VIBRATE_SETTING, SHARED_MSG, SENDMSG_NOOP, 0, 0,

null, 0);

}

同样将振动模式写入数据库,并广播该模式.

3 硬件服务
文件：frameworks/base/services/java/com/android/server/HardwareService.java

开始振动：

public void vibrate(long milliseconds, IBinder token) {

if (mContext.checkCallingOrSelfPermission(android.Manifest.permission.VIBRATE)

!= PackageManager.PERMISSION_GRANTED) {

throw new SecurityException("Requires VIBRATE permission");

}

// We're running in the system server so we cannot crash. Check for a

// timeout of 0 or negative. This will ensure that a vibration has

// either a timeout of > 0 or a non-null pattern.

if (milliseconds <= 0 || (mCurrentVibration != null

&& mCurrentVibration.hasLongerTimeout(milliseconds))) {

// Ignore this vibration since the current vibration will play for

// longer than milliseconds.

return;

}

Vibration vib = new Vibration(token, milliseconds);

synchronized (mVibrations) {

removeVibrationLocked(token);

doCancelVibrateLocked();

mCurrentVibration = vib;

startVibrationLocked(vib);

}

}

private void startVibrationLocked(final Vibration vib) {

if (vib.mTimeout != 0) {

vibratorOn(vib.mTimeout);

mH.postDelayed(mVibrationRunnable, vib.mTimeout);

} else {

// mThread better be null here. doCancelVibrate should always be

// called before startNextVibrationLocked or startVibrationLocked.

mThread = new VibrateThread(vib);

mThread.start();

}

}

该接口允许设置振动的时间长度，通过调用vibratorOn(vib.mTimeout);实现对底层硬件的操作。

取消振动：

public void cancelVibrate(IBinder token) {

mContext.enforceCallingOrSelfPermission(

android.Manifest.permission.VIBRATE,

"cancelVibrate");

// so wakelock calls will succeed

long identity = Binder.clearCallingIdentity();

try {

synchronized (mVibrations) {

final Vibration vib = removeVibrationLocked(token);

if (vib == mCurrentVibration) {

doCancelVibrateLocked();

startNextVibrationLocked();

}

}

}

finally {

Binder.restoreCallingIdentity(identity);

}

}

private void doCancelVibrateLocked() {

if (mThread != null) {

synchronized (mThread) {

mThread.mDone = true;

mThread.notify();

}

mThread = null;

}

vibratorOff ();

mH.removeCallbacks(mVibrationRunnable);

}

该接口允许停止振动，通过调用vibratorOff();实现对底层硬件的操作。

4 硬件调用
vibratorOn、vibratorOff对应的jni代码如下：

文件：frameworks/base/services/jni/com_android_server_HardwareService.cpp

static void vibratorOn(JNIEnv *env, jobject clazz, jlong timeout_ms)

{

// LOGI("vibratorOn\n");

vibrator_on(timeout_ms);

}

static void vibratorOff(JNIEnv *env, jobject clazz)

{

// LOGI("vibratorOff\n");

vibrator_off();

}

vibrator_on、vibrator_off 接口的提供者为如下硬件原型。

5, 硬件原型
文件：hardware/libhardware_legacy/vibrator/vibrator.c

#define THE_DEVICE "/sys/class/timed_output/vibrator/enable"

static int sendit(int timeout_ms)

{

int nwr, ret, fd;

char value[20];

#ifdef QEMU_HARDWARE

if (qemu_check()) {

return qemu_control_command( "vibrator:%d", timeout_ms );

}

#endif

fd = open(THE_DEVICE, O_RDWR);

if(fd < 0)

return errno;

nwr = sprintf(value, "%d\n", timeout_ms);

ret = write(fd, value, nwr);

close(fd);

return (ret == nwr) ? 0 : -1;

}

int vibrator_on(int timeout_ms)

{

/* constant on, up to maximum allowed time */

return sendit(timeout_ms);

}

int vibrator_off()

{

return sendit(0);

}

由以上代码可知，开启振动时是往文件/sys/class/timed_output/vibrator/enable写入振动的时间长度；关闭振动时，其时间长度为0。/sys/class/timed_output/vibrator/enable 的真实路径根据实际作修改。

6,驱动代码

创建timed_output类

kernel\drivers\staging\android\Timed_output.c

在sys/class目录创建timed_output子目录和文件enable

timed_output_class = class_create(THIS_MODULE, "timed_output");创建timed_output子目录

ret = device_create_file(tdev->dev, &dev_attr_enable);在sys/class/timed_output子目录创建文件enable

static int create_timed_output_class(void)
{
if (!timed_output_class) {
timed_output_class = class_create(THIS_MODULE, "timed_output");
if (IS_ERR(timed_output_class))
return PTR_ERR(timed_output_class);
atomic_set(&device_count, 0);
}

return 0;
}

int timed_output_dev_register(struct timed_output_dev *tdev)
{
int ret;

if (!tdev || !tdev->name || !tdev->enable || !tdev->get_time)
return -EINVAL;

ret = create_timed_output_class();
if (ret < 0)
return ret;

tdev->index = atomic_inc_return(&device_count);
tdev->dev = device_create(timed_output_class, NULL,
MKDEV(0, tdev->index), NULL, tdev->name);
if (IS_ERR(tdev->dev))
return PTR_ERR(tdev->dev);

ret = device_create_file(tdev->dev, &dev_attr_enable);
if (ret < 0)
goto err_create_file;

dev_set_drvdata(tdev->dev, tdev);
tdev->state = 0;
return 0;

err_create_file:
device_destroy(timed_output_class, MKDEV(0, tdev->index));
printk(KERN_ERR "timed_output: Failed to register driver %s\n",
tdev->name);

return ret;
}
EXPORT_SYMBOL_GPL(timed_output_dev_register);

驱动注册马达的驱动，注册一个定时器用于控制震动时间（回调函数vibrator_timer_func），注册两个队列，一共给马达打开用，一共为马达震动关闭用。

static void pmic_vibrator_on(struct work_struct *work)
{
set_pmic_vibrator(1);
}

static void pmic_vibrator_off(struct work_struct *work)
{
set_pmic_vibrator(0);
}

static void timed_vibrator_on(struct timed_output_dev *sdev)
{
schedule_work(&work_vibrator_on);
}

static void timed_vibrator_off(struct timed_output_dev *sdev)
{
schedule_work(&work_vibrator_off);
}

static void vibrator_enable(struct timed_output_dev *dev, int value)
{
hrtimer_cancel(&vibe_timer);

if (value == 0)
timed_vibrator_off(dev);
else {
value = (value > 15000 ? 15000 : value);

timed_vibrator_on(dev);

hrtimer_start(&vibe_timer,
ktime_set(value / 1000, (value % 1000) * 1000000),
HRTIMER_MODE_REL);
}
}

static int vibrator_get_time(struct timed_output_dev *dev)
{
if (hrtimer_active(&vibe_timer)) {
ktime_t r = hrtimer_get_remaining(&vibe_timer);
return r.tv.sec * 1000 + r.tv.nsec / 1000000;
} else
return 0;
}

static enum hrtimer_restart vibrator_timer_func(struct hrtimer *timer)
{
timed_vibrator_off(NULL);
return HRTIMER_NORESTART;
}

static struct timed_output_dev pmic_vibrator = {
.name = "vibrator",
.get_time = vibrator_get_time,
.enable = vibrator_enable,
};

void __init pxa_init_pmic_vibrator(void)
{
INIT_WORK(&work_vibrator_on, pmic_vibrator_on);
INIT_WORK(&work_vibrator_off, pmic_vibrator_off);

hrtimer_init(&vibe_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
vibe_timer.function = vibrator_timer_func;

timed_output_dev_register(&pmic_vibrator);
}

当上层要设置马达震动时，往文件/sys/class/timed_output/vibrator/enable写入振动的时间长度，通过

static ssize_t enable_store(
struct device *dev, struct device_attribute *attr,
const char *buf, size_t size)
{
struct timed_output_dev *tdev = dev_get_drvdata(dev);
int value;

sscanf(buf, "%d", &value);
tdev->enable(tdev, value);

return size;
}

调用驱动的enable函数也就是vibrator_enable（ .enable = vibrator_enable,）

vibrator_enable

|

|

v

timed_vibrator_on(dev);

|

|

v

schedule_work(&work_vibrator_on);

|

|

v

pmic_vibrator_on

|

|

v

set_pmic_vibrator(1); //给马达供电震动

|

|

v

hrtimer_start(&vibe_timer,
ktime_set(value / 1000, (value % 1000) * 1000000),
HRTIMER_MODE_REL);

最终是设置马达的硬件控制驱动管给马达供电，并且启动定时器，定时时间是上层给的参数。

定时时间到了就调用定时器的回调函数vibrator_timer_func
vibrator_timer_func

|

|

v

timed_vibrator_off(NULL);

|

|

v

schedule_work(&work_vibrator_off);

|

|

v

pmic_vibrator_off

|

|

v

set_pmic_vibrator(0); //断开马达的供电，马达停止震动

最终是设置马达的硬件控制驱动管断开马达供电，停止马达震动

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