Bug debugging for sensor in high-pass non-ADSP architecture

• Qualcomm sensor from native to Hal
• High-pass HAL layer of sensor HAL
• Bmp18x.cpp of the high-pass HAL Layer

Problem phenomenon:

After hibernation, when the preesure sensor is opened again, there will be a period of time after the APK will appear data; (data can sometimes be difficult to show)

Problem Analysis:

From the above sections, we can know that the framework to HAL is removed by invoking the call sensors.msm8909.so into the function PressureSensor::readEvents ;

int pressuresensor::readevents (sensors_event_t* data, int count) {int i = 0;    if (count < 1) return-einval;        if (mhaspendingevent) {mhaspendingevent = false;        Mpendingevent.timestamp = Gettimestamp ();        *data = mpendingevent; Return menabled?    1:0;        } if (mhaspendingmetadata) {mhaspendingmetadata--;        Meta_data.timestamp = Gettimestamp ();        *data = Meta_data; Return menabled?    1:0;    } ssize_t n = Minputreader.fill (DATA_FD);    if (n < 0) return n;    int numeventreceived = 0; Input_event const* event; #if Fetch_full_event_before_returnagain: #endif while (Count &&        Minputreader.readevent (&event)) {int type = event->type;            if (type = = Ev_abs) {Float value = event->value;            Mpendingevent.pressure = value * convert_pressure;        Alogi ("The Pressure is%f\n", mpendingevent.pressure); } else if (type = = Ev_syn) {SwitCH (event->code) {case syn_time_sec:museabstimestamp = true;                    Report_time = event->value*1000000000ll;                Break                    Case Syn_time_nsec:museabstimestamp = true;                    Mpendingevent.timestamp = report_time+event->value;                Break Case Syn_report:if (Museabstimestamp! = True) {Mpendingevent.timestamp = Timeva                    Ltonano (Event->time); } if (menabled) {//Alogi ("timestamp =%ld Menabledtime =%ld Museabstimestamp =% D Enable here\n ", Mpendingevent.timestamp, Menabledtime, museabstimestamp);//if (mpendingevent.times                            Tamp >= menabledtime) {*data = mpendingevent; Alogi ("Data pressure is%f\n", data->pressure);//DAta++;                        numeventreceived++;                    } count--;            } break; }} else {Aloge ("Pressuresensor:unknown event (type=%d, code=%d)", type, event->        code);    } minputreader.next (); } #if Fetch_full_event_before_return/* If we didn ' t read a complete EVENT, see if we can fill and try again inste Ad of returning with nothing and redoing poll.        */if (numeventreceived = = 0 && menabled = = 1) {n = Minputreader.fill (DATA_FD);    if (n) goto again;    } #endif Alogi ("End the data the pressure is%f\n", mpendingevent.pressure); return numeventreceived;}

Increasing if (mPendingEvent.timestamp >= mEnabledTime) judgment is to judge SYN_REPORT the situation without delay;

mPendingEvent.timestampHere is the value assigned:

input_event const* event;//这个可以一直进来if(mUseAbsTimeStamp != true) {  mPendingEvent.timestamp = timevalToNano(event->time);}

event->timeRepresents the keystroke time, which can be used to struct timeval get the system time.
input_eventand the timeval structure of the body is as follows:

struct input_event {struct timeval time; //按键时间__u16 type; //类型，在下面有定义__u16 code; //要模拟成什么按键__s32 value;//是按下还是释放};struct timeval {   __kernel_time_t        tv_sec;     /* seconds */  __kernel_suseconds_t    tv_usec;    /* microseconds */};

//将时间转换为nsstatic int64_t timevalToNano(timeval const& t) {      return t.tv_sec*1000000000LL + t.tv_usec*1000;}

By printing can know that the problem occurs when the time mPendingEvent.timestamp is less than mEnabledTime the judgment, so the upper layer will not be able to obtain the corresponding data;

mEnabledTimeis implemented in a int PressureSensor::enable(int32_t, int en) function:

....    mEnabledTime = getTimestamp() + IGNORE_EVENT_TIME;....

int64_t SensorBase::getTimestamp() {    struct timespec t;    t.tv_sec = t.tv_nsec = 0;    clock_gettime(CLOCK_BOOTTIME, &t);    return int64_t(t.tv_sec)*1000000000LL + t.tv_nsec;}//不过CLOCK_BOOTTIME计算系统suspend的时间，也就是说，不论是running还是suspend（这些都算是启动时间），CLOCK_BOOTTIME都会累积计时，直到系统reset或者shutdown。

So in the sleep mEnabledTime will be greater than mPendingEvent.timestamp , so at this time there is no reporting data, the judgment can be removed;

Patch Address

Patch