LCD在打电话时不灭屏的解决方法

环境：MSM8909+Android6.0.1+STK3310

1.打开QSensorTest app，用手靠近和远离P-sensor，sensor均能正常上报数据。
2.打电话时查看kernel日志，发现enable函数没有被调用。

P-sensor采用的轮训的方式上报数据，说明上层没有调用sensor的enable函数，在frameworks/base/core/java/android/hardware/SensorManager.java文件中：

/** * Use this method to get the default sensor for a given type. Note that the * returned sensor could be a composite sensor, and its data could be * averaged or filtered. If you need to access the raw sensors use * {@link SensorManager#getSensorList(int) getSensorList}. * * @param type *         of sensors requested * * @return the default sensor matching the requested type if one exists and the application *         has the necessary permissions, or null otherwise. * * @see #getSensorList(int) * @see Sensor */public Sensor getDefaultSensor(int type) {    // TODO: need to be smarter, for now, just return the 1st sensor    List<Sensor> l = getSensorList(type);    boolean wakeUpSensor = false;    // For the following sensor types, return a wake-up sensor. These types are by default    // defined as wake-up sensors. For the rest of the SDK defined sensor types return a    // non_wake-up version.    if (type == Sensor.TYPE_PROXIMITY || type == Sensor.TYPE_SIGNIFICANT_MOTION ||            type == Sensor.TYPE_TILT_DETECTOR || type == Sensor.TYPE_WAKE_GESTURE ||            type == Sensor.TYPE_GLANCE_GESTURE || type == Sensor.TYPE_PICK_UP_GESTURE ||            type == Sensor.TYPE_WRIST_TILT_GESTURE) {        wakeUpSensor = true;    }    for (Sensor sensor : l) {        if (sensor.isWakeUpSensor() == wakeUpSensor) return sensor;    }    return null;}

如果是wakeUpSensor，则正常返回。调用到这的时候，返回的是NULL。在hardware/libhardware/include/hardware/sensors.h中有对wake_up_sensor的详细说明：

/* * Availability: SENSORS_DEVICE_API_VERSION_1_3 * Sensor flags used in sensor_t.flags. */enum {    /*     * Whether this sensor wakes up the AP from suspend mode when data is available.  Whenever     * sensor events are delivered from a wake_up sensor, the driver needs to hold a wake_lock till     * the events are read by the SensorService i.e till sensors_poll_device_t.poll() is called the     * next time. Once poll is called again it means events have been read by the SensorService, the     * driver can safely release the wake_lock. SensorService will continue to hold a wake_lock till     * the app actually reads the events.     */    SENSOR_FLAG_WAKE_UP = 1U << 0,    /*     * Reporting modes for various sensors. Each sensor will have exactly one of these modes set.     * The least significant 2nd, 3rd and 4th bits are used to represent four possible reporting     * modes.     */    SENSOR_FLAG_CONTINUOUS_MODE        = 0,    // 0000    SENSOR_FLAG_ON_CHANGE_MODE         = 0x2,  // 0010    SENSOR_FLAG_ONE_SHOT_MODE          = 0x4,  // 0100    SENSOR_FLAG_SPECIAL_REPORTING_MODE = 0x6,  // 0110    /*     * Set this flag if the sensor supports data_injection mode and allows data to be injected     * from the SensorService. When in data_injection ONLY sensors with this flag set are injected     * sensor data and only sensors with this flag set are activated. Eg: Accelerometer and Step     * Counter sensors can be set with this flag and SensorService will inject accelerometer data     * and read the corresponding step counts.     */    SENSOR_FLAG_SUPPORTS_DATA_INJECTION = 0x10  // 1 0000};

如果是wake_up_sensor的话，需要设置SENSOR_FLAG_WAKE_UP标志，在hardware/qcom/sensors/NativeSensorManager.cpp的int NativeSensorManager::getDataInfo函数中：

case SENSOR_TYPE_PROXIMITY:has_proximity = 1;#if defined(SENSORS_DEVICE_API_VERSION_1_3)/* reporting mode fix up */list->sensor->flags |= SENSOR_FLAG_ON_CHANGE_MODE;#endiflist->driver = new ProximitySensor(list);sensor_proximity = *(list->sensor);break;

SENSOR_FLAG_ON_CHANGE_MODE等于2，或上SENSOR_FLAG_WAKE_UP之后就是3，因此，driver中的flags配置成3即可。

static struct sensors_classdev sensors_proximity_cdev = {.name = "stk3x1x-proximity",.vendor = "Sensortek",.version = 1,.handle = SENSORS_PROXIMITY_HANDLE,.type = SENSOR_TYPE_PROXIMITY,.max_range = "5.0",.resolution = "5.0",.sensor_power = "0.1",.min_delay = 0,.fifo_reserved_event_count = 0,.fifo_max_event_count = 0,.flags = 3,.enabled = 0,.delay_msec = 200,.sensors_enable = NULL,.sensors_poll_delay = NULL,};