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      1 /*
      2  * Copyright (C) 2008 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 <fcntl.h>
     18 #include <errno.h>
     19 #include <math.h>
     20 #include <poll.h>
     21 #include <unistd.h>
     22 #include <dirent.h>
     23 #include <sys/select.h>
     24 
     25 #include <linux/capella_cm3602.h>
     26 
     27 #include <cutils/log.h>
     28 
     29 #include "ProximitySensor.h"
     30 
     31 /*****************************************************************************/
     32 
     33 ProximitySensor::ProximitySensor()
     34     : SensorBase(CM_DEVICE_NAME, "proximity"),
     35       mEnabled(0),
     36       mInputReader(4),
     37       mHasPendingEvent(false)
     38 {
     39     mPendingEvent.version = sizeof(sensors_event_t);
     40     mPendingEvent.sensor = ID_P;
     41     mPendingEvent.type = SENSOR_TYPE_PROXIMITY;
     42     memset(mPendingEvent.data, 0, sizeof(mPendingEvent.data));
     43 
     44     open_device();
     45 
     46     int flags = 0;
     47     if (!ioctl(dev_fd, CAPELLA_CM3602_IOCTL_GET_ENABLED, &flags)) {
     48         mEnabled = 1;
     49         if (flags) {
     50             setInitialState();
     51         }
     52     }
     53     if (!mEnabled) {
     54         close_device();
     55     }
     56 }
     57 
     58 ProximitySensor::~ProximitySensor() {
     59 }
     60 
     61 int ProximitySensor::setInitialState() {
     62     struct input_absinfo absinfo;
     63     if (!ioctl(data_fd, EVIOCGABS(EVENT_TYPE_PROXIMITY), &absinfo)) {
     64         // make sure to report an event immediately
     65         mHasPendingEvent = true;
     66         mPendingEvent.distance = indexToValue(absinfo.value);
     67     }
     68     return 0;
     69 }
     70 
     71 int ProximitySensor::enable(int32_t, int en) {
     72     int newState = en ? 1 : 0;
     73     int err = 0;
     74     if (newState != mEnabled) {
     75         if (!mEnabled) {
     76             open_device();
     77         }
     78         int flags = newState;
     79         err = ioctl(dev_fd, CAPELLA_CM3602_IOCTL_ENABLE, &flags);
     80         err = err<0 ? -errno : 0;
     81         LOGE_IF(err, "CAPELLA_CM3602_IOCTL_ENABLE failed (%s)", strerror(-err));
     82         if (!err) {
     83             mEnabled = newState;
     84             if (en) {
     85                 setInitialState();
     86             }
     87         }
     88         if (!mEnabled) {
     89             close_device();
     90         }
     91     }
     92     return err;
     93 }
     94 
     95 bool ProximitySensor::hasPendingEvents() const {
     96     return mHasPendingEvent;
     97 }
     98 
     99 int ProximitySensor::readEvents(sensors_event_t* data, int count)
    100 {
    101     if (count < 1)
    102         return -EINVAL;
    103 
    104     if (mHasPendingEvent) {
    105         mHasPendingEvent = false;
    106         mPendingEvent.timestamp = getTimestamp();
    107         *data = mPendingEvent;
    108         return mEnabled ? 1 : 0;
    109     }
    110 
    111     ssize_t n = mInputReader.fill(data_fd);
    112     if (n < 0)
    113         return n;
    114 
    115     int numEventReceived = 0;
    116     input_event const* event;
    117 
    118     while (count && mInputReader.readEvent(&event)) {
    119         int type = event->type;
    120         if (type == EV_ABS) {
    121             if (event->code == EVENT_TYPE_PROXIMITY) {
    122                 mPendingEvent.distance = indexToValue(event->value);
    123             }
    124         } else if (type == EV_SYN) {
    125             mPendingEvent.timestamp = timevalToNano(event->time);
    126             if (mEnabled) {
    127                 *data++ = mPendingEvent;
    128                 count--;
    129                 numEventReceived++;
    130             }
    131         } else {
    132             LOGE("ProximitySensor: unknown event (type=%d, code=%d)",
    133                     type, event->code);
    134         }
    135         mInputReader.next();
    136     }
    137 
    138     return numEventReceived;
    139 }
    140 
    141 float ProximitySensor::indexToValue(size_t index) const
    142 {
    143     return index * PROXIMITY_THRESHOLD_CM;
    144 }
    145