/*
 * Copyright (C) 2010 Danijel Posilovic - dan1j3l
 * Copyright (C) 2008 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#define LOG_TAG "Sensors"

#define LOG_NDEBUG 1

#include <hardware/sensors.h>
#include <fcntl.h>
#include <errno.h>
#include <dirent.h>
#include <math.h>
#include <poll.h>
#include <pthread.h>
#include <sys/select.h>

#include <linux/input.h>
#include <linux/akm8973.h>
#include <linux/capella_cm3602.h>
#include <linux/lightsensor.h>

#include <cutils/atomic.h>
#include <cutils/log.h>
#include <cutils/native_handle.h>

#define __MAX(a,b) ((a)>=(b)?(a):(b))

/*****************************************************************************/

#define MAX_NUM_SENSORS 6

#define SUPPORTED_SENSORS  ((1<<MAX_NUM_SENSORS)-1)

#define ARRAY_SIZE(a) (sizeof(a) / sizeof(a[0]))

#define ID_A  (0)
#define ID_M  (1)
#define ID_O  (2)
#define ID_T  (3)
#define ID_P  (4)
#define ID_L  (5)

static int id_to_sensor[MAX_NUM_SENSORS] = {
    [ID_A] = SENSOR_TYPE_ACCELEROMETER,
    [ID_M] = SENSOR_TYPE_MAGNETIC_FIELD,
    [ID_O] = SENSOR_TYPE_ORIENTATION,
    [ID_T] = SENSOR_TYPE_TEMPERATURE,
    [ID_P] = SENSOR_TYPE_PROXIMITY,
    [ID_L] = SENSOR_TYPE_LIGHT,
};

#define SENSORS_AKM_ACCELERATION   (1<<ID_A)
#define SENSORS_AKM_MAGNETIC_FIELD (1<<ID_M)
#define SENSORS_AKM_ORIENTATION    (1<<ID_O)
#define SENSORS_AKM_TEMPERATURE    (1<<ID_T)
#define SENSORS_AKM_GROUP          ((1<<ID_A)|(1<<ID_M)|(1<<ID_O)|(1<<ID_T))

#define SENSORS_CM_PROXIMITY       (1<<ID_P)
#define SENSORS_CM_GROUP           (1<<ID_P)

#define SENSORS_LIGHT              (1<<ID_L)
#define SENSORS_LIGHT_GROUP        (1<<ID_L)

/*****************************************************************************/

struct sensors_control_context_t {
    struct sensors_control_device_t device; // must be first
    int akmd_fd;
    int cmd_fd;
    int lsd_fd;
    uint32_t active_sensors;
};

struct sensors_data_context_t {
    struct sensors_data_device_t device; // must be first
    int events_fd[3];
    sensors_data_t sensors[MAX_NUM_SENSORS];
    uint32_t pendingSensors;
};

/*
 * The SENSORS Module
 */

/* the CM3602 is a binary proximity sensor that triggers around 9 cm on
 * this hardware */
#define PROXIMITY_THRESHOLD_CM  9.0f

/*
 * the AK8973 has a 8-bit ADC but the firmware seems to average 16 samples,
 * or at least makes its calibration on 12-bits values. This increases the
 * resolution by 4 bits.
 */

static const struct sensor_t sSensorList[] = {
        { "BMA150 3-axis Accelerometer",
                "Bosh",
                1, SENSORS_HANDLE_BASE+ID_A,
                SENSOR_TYPE_ACCELEROMETER, 4.0f*9.81f, (4.0f*9.81f)/256.0f, 0.2f, { } },
        { "AK8973 3-axis Magnetic field sensor",
                "Asahi Kasei",
                1, SENSORS_HANDLE_BASE+ID_M,
                SENSOR_TYPE_MAGNETIC_FIELD, 2000.0f, 1.0f/16.0f, 6.8f, { } },
        { "AK8973 Orientation sensor",
                "Asahi Kasei",
                1, SENSORS_HANDLE_BASE+ID_O,
                SENSOR_TYPE_ORIENTATION, 360.0f, 1.0f, 7.0f, { } },
        { "CM3602 Proximity sensor",
                "Capella Microsystems",
                1, SENSORS_HANDLE_BASE+ID_P,
                SENSOR_TYPE_PROXIMITY,
                PROXIMITY_THRESHOLD_CM, PROXIMITY_THRESHOLD_CM,
                0.5f, { } },
        { "CM3602 Light sensor",
                "Capella Microsystems",
                1, SENSORS_HANDLE_BASE+ID_L,
                SENSOR_TYPE_LIGHT, 10240.0f, 1.0f, 0.5f, { } },
};

static const float sLuxValues[8] = {
    10.0,
    160.0,
    225.0,
    320.0,
    640.0,
    1280.0,
    2600.0,
    10240.0
};

static int open_sensors(const struct hw_module_t* module, const char* name,
        struct hw_device_t** device);

static int sensors__get_sensors_list(struct sensors_module_t* module,
        struct sensor_t const** list)
{
    *list = sSensorList;
    return ARRAY_SIZE(sSensorList);
}

static struct hw_module_methods_t sensors_module_methods = {
    .open = open_sensors
};

const struct sensors_module_t HAL_MODULE_INFO_SYM = {
    .common = {
        .tag = HARDWARE_MODULE_TAG,
        .version_major = 1,
        .version_minor = 0,
        .id = SENSORS_HARDWARE_MODULE_ID,
        .name = "AK8973A & CM3602 Sensors Module",
        .author = "The Android Open Source Project",
        .methods = &sensors_module_methods,
    },
    .get_sensors_list = sensors__get_sensors_list
};

/*****************************************************************************/

#define AKM_DEVICE_NAME     "/dev/akm8973_aot"
#define CM_DEVICE_NAME      "/dev/cm3602"
#define LS_DEVICE_NAME      "/dev/lightsensor"


// sensor IDs must be a power of two and
// must match values in SensorManager.java
#define EVENT_TYPE_ACCEL_X          ABS_X
#define EVENT_TYPE_ACCEL_Y          ABS_Z
#define EVENT_TYPE_ACCEL_Z          ABS_Y
#define EVENT_TYPE_ACCEL_STATUS     ABS_WHEEL

#define EVENT_TYPE_YAW              ABS_RX
#define EVENT_TYPE_PITCH            ABS_RY
#define EVENT_TYPE_ROLL             ABS_RZ
#define EVENT_TYPE_ORIENT_STATUS    ABS_RUDDER

#define EVENT_TYPE_MAGV_X           ABS_HAT0X
#define EVENT_TYPE_MAGV_Y           ABS_HAT0Y
#define EVENT_TYPE_MAGV_Z           ABS_BRAKE

#define EVENT_TYPE_TEMPERATURE      ABS_THROTTLE
#define EVENT_TYPE_STEP_COUNT       ABS_GAS
#define EVENT_TYPE_PROXIMITY        ABS_DISTANCE
#define EVENT_TYPE_LIGHT            ABS_MISC

// 720 LSG = 1G
#define LSG                         (720.0f)


// conversion of acceleration data to SI units (m/s^2)
#define CONVERT_A                   (GRAVITY_EARTH / LSG)
#define CONVERT_A_X                 (-CONVERT_A)
#define CONVERT_A_Y                 (CONVERT_A)
#define CONVERT_A_Z                 (-CONVERT_A)

// conversion of magnetic data to uT units
#define CONVERT_M                   (1.0f/16.0f)
#define CONVERT_M_X                 (-CONVERT_M)
#define CONVERT_M_Y                 (-CONVERT_M)
#define CONVERT_M_Z                 (CONVERT_M)

#define SENSOR_STATE_MASK           (0x7FFF)

/*****************************************************************************/

static int open_inputs(int mode, int *akm_fd, int *p_fd, int *l_fd)
{
    /* scan all input drivers and look for "compass" */
    int fd = -1;
    const char *dirname = "/dev/input";
    char devname[PATH_MAX];
    char *filename;
    DIR *dir;
    struct dirent *de;
    dir = opendir(dirname);
    if(dir == NULL)
        return -1;
    strcpy(devname, dirname);
    filename = devname + strlen(devname);
    *filename++ = '/';
    *akm_fd = *p_fd = -1;
    while((de = readdir(dir))) {
        if(de->d_name[0] == '.' &&
           (de->d_name[1] == '\0' ||
            (de->d_name[1] == '.' && de->d_name[2] == '\0')))
            continue;
        strcpy(filename, de->d_name);
        fd = open(devname, mode);
        if (fd>=0) {
            char name[80];
            if (ioctl(fd, EVIOCGNAME(sizeof(name) - 1), &name) < 1) {
                name[0] = '\0';
            }
            if (!strcmp(name, "compass")) {
                LOGV("using %s (name=%s)", devname, name);
                *akm_fd = fd;
            }
            else if (!strcmp(name, "proximity")) {
                LOGV("using %s (name=%s)", devname, name);
                *p_fd = fd;
            }
            else if (!strcmp(name, "lightsensor-level")) {
                LOGV("using %s (name=%s)", devname, name);
                *l_fd = fd;
            }
            else
                close(fd);
        }
    }
    closedir(dir);

    fd = 0;
    if (*akm_fd < 0) {
        LOGE("Couldn't find or open 'compass' driver (%s)", strerror(errno));
        fd = -1;
    }
    if (*p_fd < 0) {
        LOGE("Couldn't find or open 'proximity' driver (%s)", strerror(errno));
        fd = -1;
    }
    if (*l_fd < 0) {
        LOGE("Couldn't find or open 'light' driver (%s)", strerror(errno));
        fd = -1;
    }
    return fd;
}

static int open_akm(struct sensors_control_context_t* dev)
{
    if (dev->akmd_fd < 0) {
        dev->akmd_fd = open(AKM_DEVICE_NAME, O_RDONLY);
        LOGV("%s, fd=%d", __PRETTY_FUNCTION__, dev->akmd_fd);
        LOGE_IF(dev->akmd_fd<0, "Couldn't open %s (%s)",
                AKM_DEVICE_NAME, strerror(errno));
        if (dev->akmd_fd >= 0) {
            dev->active_sensors &= ~SENSORS_AKM_GROUP;
        }
    }
    return dev->akmd_fd;
}

static void close_akm(struct sensors_control_context_t* dev)
{
    if (dev->akmd_fd >= 0) {
        LOGV("%s, fd=%d", __PRETTY_FUNCTION__, dev->akmd_fd);
        close(dev->akmd_fd);
        dev->akmd_fd = -1;
    }
}

static uint32_t read_akm_sensors_state(int fd)
{
    short flags;
    uint32_t sensors = 0;
    // read the actual value of all sensors
    if (!ioctl(fd, ECS_IOCTL_APP_GET_MFLAG, &flags)) {
        if (flags)  sensors |= SENSORS_AKM_ORIENTATION;
        else        sensors &= ~SENSORS_AKM_ORIENTATION;
    }
    if (!ioctl(fd, ECS_IOCTL_APP_GET_AFLAG, &flags)) {
        if (flags)  sensors |= SENSORS_AKM_ACCELERATION;
        else        sensors &= ~SENSORS_AKM_ACCELERATION;
    }
    if (!ioctl(fd, ECS_IOCTL_APP_GET_TFLAG, &flags)) {
        if (flags)  sensors |= SENSORS_AKM_TEMPERATURE;
        else        sensors &= ~SENSORS_AKM_TEMPERATURE;
    }
    if (!ioctl(fd, ECS_IOCTL_APP_GET_MVFLAG, &flags)) {
        if (flags)  sensors |= SENSORS_AKM_MAGNETIC_FIELD;
        else        sensors &= ~SENSORS_AKM_MAGNETIC_FIELD;
    }
    return sensors;
}

static uint32_t enable_disable_akm(struct sensors_control_context_t *dev,
                                   uint32_t active, uint32_t sensors,
                                   uint32_t mask)
{
    uint32_t now_active_akm_sensors;

    int fd = open_akm(dev);
    if (fd < 0)
        return 0;

    LOGV("(before) akm sensors = %08x, real = %08x",
         sensors, read_akm_sensors_state(fd));

    short flags;
    if (mask & SENSORS_AKM_ORIENTATION) {
        flags = (sensors & SENSORS_AKM_ORIENTATION) ? 1 : 0;
        if (ioctl(fd, ECS_IOCTL_APP_SET_MFLAG, &flags) < 0) {
            LOGE("ECS_IOCTL_APP_SET_MFLAG error (%s)", strerror(errno));
        }
    }
    if (mask & SENSORS_AKM_ACCELERATION) {
        flags = (sensors & SENSORS_AKM_ACCELERATION) ? 1 : 0;
        if (ioctl(fd, ECS_IOCTL_APP_SET_AFLAG, &flags) < 0) {
            LOGE("ECS_IOCTL_APP_SET_AFLAG error (%s)", strerror(errno));
        }
    }
    if (mask & SENSORS_AKM_TEMPERATURE) {
        flags = (sensors & SENSORS_AKM_TEMPERATURE) ? 1 : 0;
        if (ioctl(fd, ECS_IOCTL_APP_SET_TFLAG, &flags) < 0) {
            LOGE("ECS_IOCTL_APP_SET_TFLAG error (%s)", strerror(errno));
        }
    }
    if (mask & SENSORS_AKM_MAGNETIC_FIELD) {
        flags = (sensors & SENSORS_AKM_MAGNETIC_FIELD) ? 1 : 0;
        if (ioctl(fd, ECS_IOCTL_APP_SET_MVFLAG, &flags) < 0) {
            LOGE("ECS_IOCTL_APP_SET_MVFLAG error (%s)", strerror(errno));
        }
    }

    now_active_akm_sensors = read_akm_sensors_state(fd);

    LOGV("(after) akm sensors = %08x, real = %08x",
         sensors, now_active_akm_sensors);

    if (!sensors)
        close_akm(dev);

    return now_active_akm_sensors;
}

static uint32_t read_cm_sensors_state(int fd)
{
    int flags;
    uint32_t sensors = 0;
    // read the actual value of all sensors
    if (!ioctl(fd, CAPELLA_CM3602_IOCTL_GET_ENABLED, &flags)) {
        if (flags)  sensors |= SENSORS_CM_PROXIMITY;
        else        sensors &= ~SENSORS_CM_PROXIMITY;
    }

    return sensors;
}

static int open_cm(struct sensors_control_context_t* dev)
{
    if (dev->cmd_fd < 0) {
        dev->cmd_fd = open(CM_DEVICE_NAME, O_RDONLY);
        LOGV("%s, fd=%d", __PRETTY_FUNCTION__, dev->cmd_fd);
        LOGE_IF(dev->cmd_fd<0, "Couldn't open %s (%s)",
                CM_DEVICE_NAME, strerror(errno));
        if (dev->cmd_fd >= 0) {
            dev->active_sensors &= ~SENSORS_CM_GROUP;
        }
    }
    return dev->cmd_fd;
}

static void close_cm(struct sensors_control_context_t* dev)
{
    if (dev->cmd_fd >= 0) {
        LOGV("%s, fd=%d", __PRETTY_FUNCTION__, dev->cmd_fd);
        close(dev->cmd_fd);
        dev->cmd_fd = -1;
    }
}

static int enable_disable_cm(struct sensors_control_context_t *dev,
                             uint32_t active, uint32_t sensors, uint32_t mask)
{
    int rc = 0;
    uint32_t now_active_cm_sensors;
    int fd = open_cm(dev);

    if (fd < 0) {
        LOGE("Couldn't open %s (%s)", CM_DEVICE_NAME, strerror(errno));
        return 0;
    }

    LOGV("(before) cm sensors = %08x, real = %08x",
         sensors, read_cm_sensors_state(fd));

    if (mask & SENSORS_CM_PROXIMITY) {
        int flags = (sensors & SENSORS_CM_PROXIMITY) ? 1 : 0;
        rc = ioctl(fd, CAPELLA_CM3602_IOCTL_ENABLE, &flags);
        if (rc < 0)
            LOGE("CAPELLA_CM3602_IOCTL_ENABLE error (%s)", strerror(errno));
    }

    now_active_cm_sensors = read_cm_sensors_state(fd);

    LOGV("(after) cm sensors = %08x, real = %08x",
         sensors, now_active_cm_sensors);

    return now_active_cm_sensors;
}

static uint32_t read_ls_sensors_state(int fd)
{
    int flags;
    uint32_t sensors = 0;
    // read the actual value of all sensors
    if (!ioctl(fd, LIGHTSENSOR_IOCTL_GET_ENABLED, &flags)) {
        if (flags)  sensors |= SENSORS_LIGHT;
        else        sensors &= ~SENSORS_LIGHT;
    }

    return sensors;
}

static int open_ls(struct sensors_control_context_t* dev)
{
    if (dev->lsd_fd < 0) {
        dev->lsd_fd = open(LS_DEVICE_NAME, O_RDONLY);
        LOGV("%s, fd=%d", __PRETTY_FUNCTION__, dev->lsd_fd);
        LOGE_IF(dev->lsd_fd<0, "Couldn't open %s (%s)",
                LS_DEVICE_NAME, strerror(errno));
        if (dev->lsd_fd >= 0) {
            dev->active_sensors &= ~SENSORS_LIGHT_GROUP;
        }
    }
    return dev->lsd_fd;
}

static void close_ls(struct sensors_control_context_t* dev)
{
    if (dev->lsd_fd >= 0) {
        LOGV("%s, fd=%d", __PRETTY_FUNCTION__, dev->lsd_fd);
        close(dev->lsd_fd);
        dev->lsd_fd = -1;
    }
}

static int enable_disable_ls(struct sensors_control_context_t *dev,
                             uint32_t active, uint32_t sensors, uint32_t mask)
{
    int rc = 0;
    uint32_t now_active_ls_sensors;
    int fd = open_ls(dev);

    if (fd < 0) {
        LOGE("Couldn't open %s (%s)", LS_DEVICE_NAME, strerror(errno));
        return 0;
    }

    LOGV("(before) ls sensors = %08x, real = %08x",
         sensors, read_ls_sensors_state(fd));

    if (mask & SENSORS_LIGHT) {
        int flags = (sensors & SENSORS_LIGHT) ? 1 : 0;
        rc = ioctl(fd, LIGHTSENSOR_IOCTL_ENABLE, &flags);
        if (rc < 0)
            LOGE("LIGHTSENSOR_IOCTL_ENABLE error (%s)", strerror(errno));
    }

    now_active_ls_sensors = read_ls_sensors_state(fd);

    LOGV("(after) ls sensors = %08x, real = %08x",
         sensors, now_active_ls_sensors);

    return now_active_ls_sensors;
}

/*****************************************************************************/

static native_handle_t* control__open_data_source(struct sensors_control_context_t *dev)
{
    native_handle_t* handle;
    int akm_fd, p_fd, l_fd;

    if (open_inputs(O_RDONLY, &akm_fd, &p_fd, &l_fd) < 0 ||
            akm_fd < 0 || p_fd < 0 || l_fd < 0) {
        return NULL;
    }

    handle = native_handle_create(3, 0);
    handle->data[0] = akm_fd;
    handle->data[1] = p_fd;
    handle->data[2] = l_fd;

    return handle;
}

static int control__activate(struct sensors_control_context_t *dev,
        int handle, int enabled)
{
    if ((handle < SENSORS_HANDLE_BASE) ||
            (handle >= SENSORS_HANDLE_BASE+MAX_NUM_SENSORS))
        return -1;

    uint32_t mask = (1 << handle);
    uint32_t sensors = enabled ? mask : 0;

    uint32_t active = dev->active_sensors;
    uint32_t new_sensors = (active & ~mask) | (sensors & mask);
    uint32_t changed = active ^ new_sensors;

    if (changed) {
        if (!active && new_sensors)
            // force all sensors to be updated
            changed = SUPPORTED_SENSORS;

        dev->active_sensors =
            enable_disable_akm(dev,
                               active & SENSORS_AKM_GROUP,
                               new_sensors & SENSORS_AKM_GROUP,
                               changed & SENSORS_AKM_GROUP) |
            enable_disable_cm(dev,
                              active & SENSORS_CM_GROUP,
                              new_sensors & SENSORS_CM_GROUP,
                              changed & SENSORS_CM_GROUP) |
            enable_disable_ls(dev,
                              active & SENSORS_LIGHT_GROUP,
                              new_sensors & SENSORS_LIGHT_GROUP,
                              changed & SENSORS_LIGHT_GROUP);
    }

    return 0;
}

static int control__set_delay(struct sensors_control_context_t *dev, int32_t ms)
{
#ifdef ECS_IOCTL_APP_SET_DELAY
    if (dev->akmd_fd <= 0) {
        return -1;
    }
    short delay = ms;
    if (!ioctl(dev->akmd_fd, ECS_IOCTL_APP_SET_DELAY, &delay)) {
        return -errno;
    }
    return 0;
#else
    return -1;
#endif
}

static int control__wake(struct sensors_control_context_t *dev)
{
    int err = 0;
    int akm_fd, p_fd, l_fd;
    if (open_inputs(O_RDWR, &akm_fd, &p_fd, &l_fd) < 0 ||
            akm_fd < 0 || p_fd < 0 || l_fd < 0) {
        return -1;
    }

    struct input_event event[1];
    event[0].type = EV_SYN;
    event[0].code = SYN_CONFIG;
    event[0].value = 0;

    err = write(akm_fd, event, sizeof(event));
    LOGV_IF(err<0, "control__wake(compass), fd=%d (%s)",
            akm_fd, strerror(errno));
    close(akm_fd);

    err = write(p_fd, event, sizeof(event));
    LOGV_IF(err<0, "control__wake(proximity), fd=%d (%s)",
            p_fd, strerror(errno));
    close(p_fd);

    err = write(l_fd, event, sizeof(event));
    LOGV_IF(err<0, "control__wake(light), fd=%d (%s)",
            l_fd, strerror(errno));
    close(l_fd);

    return err;
}

/*****************************************************************************/

static int data__data_open(struct sensors_data_context_t *dev, native_handle_t* handle)
{
    int i;
    struct input_absinfo absinfo;
    memset(&dev->sensors, 0, sizeof(dev->sensors));

    for (i = 0; i < MAX_NUM_SENSORS; i++) {
        // by default all sensors have high accuracy
        // (we do this because we don't get an update if the value doesn't
        // change).
        dev->sensors[i].vector.status = SENSOR_STATUS_ACCURACY_HIGH;
    }

    dev->sensors[ID_A].sensor = SENSOR_TYPE_ACCELEROMETER;
    dev->sensors[ID_M].sensor = SENSOR_TYPE_MAGNETIC_FIELD;
    dev->sensors[ID_O].sensor = SENSOR_TYPE_ORIENTATION;
    dev->sensors[ID_T].sensor = SENSOR_TYPE_TEMPERATURE;
    dev->sensors[ID_P].sensor = SENSOR_TYPE_PROXIMITY;
    dev->sensors[ID_L].sensor = SENSOR_TYPE_LIGHT;

    dev->events_fd[0] = dup(handle->data[0]);
    dev->events_fd[1] = dup(handle->data[1]);
    dev->events_fd[2] = dup(handle->data[2]);
    LOGV("data__data_open: compass fd = %d", handle->data[0]);
    LOGV("data__data_open: proximity fd = %d", handle->data[1]);
    LOGV("data__data_open: light fd = %d", handle->data[2]);
    // Framework will close the handle
    native_handle_delete(handle);

    dev->pendingSensors = 0;
    if (!ioctl(dev->events_fd[1], EVIOCGABS(ABS_DISTANCE), &absinfo)) {
        LOGV("proximity sensor initial value %d\n", absinfo.value);
        dev->pendingSensors |= SENSORS_CM_PROXIMITY;
        // FIXME: we should save here absinfo.{minimum, maximum, etc}
        //        and use them to scale the return value according to
        //        the sensor description.
        dev->sensors[ID_P].distance = (float)absinfo.value;
    }
    else LOGE("Cannot get proximity sensor initial value: %s\n",
              strerror(errno));

    return 0;
}

static int data__data_close(struct sensors_data_context_t *dev)
{
    if (dev->events_fd[0] >= 0) {
        //LOGV("(data close) about to close compass fd=%d", dev->events_fd[0]);
        close(dev->events_fd[0]);
        dev->events_fd[0] = -1;
    }
    if (dev->events_fd[1] >= 0) {
        //LOGV("(data close) about to close proximity fd=%d", dev->events_fd[1]);
        close(dev->events_fd[1]);
        dev->events_fd[1] = -1;
    }
    if (dev->events_fd[2] >= 0) {
        //LOGV("(data close) about to close light fd=%d", dev->events_fd[1]);
        close(dev->events_fd[2]);
        dev->events_fd[2] = -1;
    }
    return 0;
}

static int pick_sensor(struct sensors_data_context_t *dev,
        sensors_data_t* values)
{
    uint32_t mask = SUPPORTED_SENSORS;
    while (mask) {
        uint32_t i = 31 - __builtin_clz(mask);
        mask &= ~(1<<i);
        if (dev->pendingSensors & (1<<i)) {
            dev->pendingSensors &= ~(1<<i);
            *values = dev->sensors[i];
            values->sensor = id_to_sensor[i];
            LOGV_IF(0, "%d [%f, %f, %f]",
                    values->sensor,
                    values->vector.x,
                    values->vector.y,
                    values->vector.z);
            return i;
        }
    }

    LOGE("no sensor to return: pendingSensors = %08x", dev->pendingSensors);
    return -1;
}

static uint32_t data__poll_process_akm_abs(struct sensors_data_context_t *dev,
                                           int fd __attribute__((unused)),
                                           struct input_event *event)
{
    uint32_t new_sensors = 0;
    if (event->type == EV_ABS) {
        LOGV("compass type: %d code: %d value: %-5d time: %ds",
             event->type, event->code, event->value,
             (int)event->time.tv_sec);
        switch (event->code) {
        case EVENT_TYPE_ACCEL_X:
            new_sensors |= SENSORS_AKM_ACCELERATION;
            dev->sensors[ID_A].acceleration.x = event->value * CONVERT_A_X;
            break;
        case EVENT_TYPE_ACCEL_Y:
            new_sensors |= SENSORS_AKM_ACCELERATION;
            dev->sensors[ID_A].acceleration.y = event->value * CONVERT_A_Y;
            break;
        case EVENT_TYPE_ACCEL_Z:
            new_sensors |= SENSORS_AKM_ACCELERATION;
            dev->sensors[ID_A].acceleration.z = event->value * CONVERT_A_Z;
            break;
        case EVENT_TYPE_MAGV_X:
            new_sensors |= SENSORS_AKM_MAGNETIC_FIELD;
            dev->sensors[ID_M].magnetic.x = event->value * CONVERT_M_X;
            break;
        case EVENT_TYPE_MAGV_Y:
            new_sensors |= SENSORS_AKM_MAGNETIC_FIELD;
            dev->sensors[ID_M].magnetic.y = event->value * CONVERT_M_Y;
            break;
        case EVENT_TYPE_MAGV_Z:
            new_sensors |= SENSORS_AKM_MAGNETIC_FIELD;
            dev->sensors[ID_M].magnetic.z = event->value * CONVERT_M_Z;
            break;
        case EVENT_TYPE_YAW:
            new_sensors |= SENSORS_AKM_ORIENTATION;
            dev->sensors[ID_O].orientation.azimuth =  event->value;
            break;
        case EVENT_TYPE_PITCH:
            new_sensors |= SENSORS_AKM_ORIENTATION;
            dev->sensors[ID_O].orientation.pitch = event->value;
            break;
        case EVENT_TYPE_ROLL:
            new_sensors |= SENSORS_AKM_ORIENTATION;
            dev->sensors[ID_O].orientation.roll = -event->value;
            break;
        case EVENT_TYPE_TEMPERATURE:
            new_sensors |= SENSORS_AKM_TEMPERATURE;
            dev->sensors[ID_T].temperature = event->value;
            break;
        case EVENT_TYPE_STEP_COUNT:
            // step count (only reported in MODE_FFD)
            // we do nothing with it for now.
            break;
        case EVENT_TYPE_ACCEL_STATUS:
            // accuracy of the calibration (never returned!)
            //LOGV("G-Sensor status %d", event->value);
            break;
        case EVENT_TYPE_ORIENT_STATUS: {
            // accuracy of the calibration
            uint32_t v = (uint32_t)(event->value & SENSOR_STATE_MASK);
            LOGV_IF(dev->sensors[ID_O].orientation.status != (uint8_t)v,
                    "M-Sensor status %d", v);
            dev->sensors[ID_O].orientation.status = (uint8_t)v;
        }
            break;
        }
    }

    return new_sensors;
}

static uint32_t data__poll_process_cm_abs(struct sensors_data_context_t *dev,
                                           int fd __attribute__((unused)),
                                          struct input_event *event)
{
    uint32_t new_sensors = 0;
    if (event->type == EV_ABS) {
        LOGV("proximity type: %d code: %d value: %-5d time: %ds",
             event->type, event->code, event->value,
             (int)event->time.tv_sec);
        if (event->code == EVENT_TYPE_PROXIMITY) {
            new_sensors |= SENSORS_CM_PROXIMITY;
            /* event->value seems to be 0 or 1, scale it to the threshold */
            dev->sensors[ID_P].distance = event->value * PROXIMITY_THRESHOLD_CM;
        }
    }
    return new_sensors;
}

static uint32_t data__poll_process_ls_abs(struct sensors_data_context_t *dev,
                                          int fd __attribute__((unused)),
                                          struct input_event *event)
{
    uint32_t new_sensors = 0;
    if (event->type == EV_ABS) {
        LOGV("light-level type: %d code: %d value: %-5d time: %ds",
             event->type, event->code, event->value,
             (int)event->time.tv_sec);
        if (event->code == EVENT_TYPE_LIGHT) {
            struct input_absinfo absinfo;
            int index;
            if (!ioctl(fd, EVIOCGABS(ABS_DISTANCE), &absinfo)) {
                index = event->value;
                if (index >= 0) {
                    new_sensors |= SENSORS_LIGHT;
                    if (index >= ARRAY_SIZE(sLuxValues)) {
                        index = ARRAY_SIZE(sLuxValues) - 1;
                    }
                    dev->sensors[ID_L].light = sLuxValues[index];
                }
            }
        }
    }
    return new_sensors;
}

static void data__poll_process_syn(struct sensors_data_context_t *dev,
                                   struct input_event *event,
                                   uint32_t new_sensors)
{
    if (new_sensors) {
        dev->pendingSensors |= new_sensors;
        int64_t t = event->time.tv_sec*1000000000LL +
            event->time.tv_usec*1000;
        while (new_sensors) {
            uint32_t i = 31 - __builtin_clz(new_sensors);
            new_sensors &= ~(1<<i);
            dev->sensors[i].time = t;
        }
    }
}

static int data__poll(struct sensors_data_context_t *dev, sensors_data_t* values)
{
    int akm_fd = dev->events_fd[0];
    int cm_fd = dev->events_fd[1];
    int ls_fd = dev->events_fd[2];

    if (akm_fd < 0) {
        LOGE("invalid compass file descriptor, fd=%d", akm_fd);
        return -1;
    }

    if (cm_fd < 0) {
        LOGE("invalid proximity-sensor file descriptor, fd=%d", cm_fd);
        return -1;
    }

    if (ls_fd < 0) {
        LOGE("invalid light-sensor file descriptor, fd=%d", ls_fd);
        return -1;
    }

    // there are pending sensors, returns them now...
    if (dev->pendingSensors) {
        LOGV("pending sensors 0x%08x", dev->pendingSensors);
        return pick_sensor(dev, values);
    }

    // wait until we get a complete event for an enabled sensor
    uint32_t new_sensors = 0;
    while (1) {
        /* read the next event; first, read the compass event, then the
           proximity event */
        struct input_event event;
        int got_syn = 0;
        int exit = 0;
        int nread;
        fd_set rfds;
        int n;

        FD_ZERO(&rfds);
        FD_SET(akm_fd, &rfds);
        FD_SET(cm_fd, &rfds);
        FD_SET(ls_fd, &rfds);
        n = select(__MAX(akm_fd, __MAX(cm_fd, ls_fd)) + 1, &rfds,
                   NULL, NULL, NULL);
        LOGV("return from select: %d\n", n);
        if (n < 0) {
            LOGE("%s: error from select(%d, %d): %s",
                 __FUNCTION__,
                 akm_fd, cm_fd, strerror(errno));
            return -1;
        }

        if (FD_ISSET(akm_fd, &rfds)) {
            nread = read(akm_fd, &event, sizeof(event));
            if (nread == sizeof(event)) {
                new_sensors |= data__poll_process_akm_abs(dev, akm_fd, &event);
                LOGV("akm abs %08x", new_sensors);
                got_syn = event.type == EV_SYN;
                exit = got_syn && event.code == SYN_CONFIG;
                if (got_syn) {
                    LOGV("akm syn %08x", new_sensors);
                    data__poll_process_syn(dev, &event, new_sensors);
                    new_sensors = 0;
                }
            }
            else LOGE("akm read too small %d", nread);
        }
        else LOGV("akm fd is not set");

        if (FD_ISSET(cm_fd, &rfds)) {
            nread = read(cm_fd, &event, sizeof(event));
            if (nread == sizeof(event)) {
                new_sensors |= data__poll_process_cm_abs(dev, cm_fd, &event);
                LOGV("cm abs %08x", new_sensors);
                got_syn |= event.type == EV_SYN;
                exit |= got_syn && event.code == SYN_CONFIG;
                if (got_syn) {
                    LOGV("cm syn %08x", new_sensors);
                    data__poll_process_syn(dev, &event, new_sensors);
                    new_sensors = 0;
                }
            }
            else LOGE("cm read too small %d", nread);
        }
        else LOGV("cm fd is not set");

        if (FD_ISSET(ls_fd, &rfds)) {
            nread = read(ls_fd, &event, sizeof(event));
            if (nread == sizeof(event)) {
                new_sensors |= data__poll_process_ls_abs(dev, ls_fd, &event);
                LOGV("ls abs %08x", new_sensors);
                got_syn |= event.type == EV_SYN;
                exit |= got_syn && event.code == SYN_CONFIG;
                if (got_syn) {
                    LOGV("ls syn %08x", new_sensors);
                    data__poll_process_syn(dev, &event, new_sensors);
                    new_sensors = 0;
                }
            }
            else LOGE("ls read too small %d", nread);
        }
        else LOGV("ls fd is not set");

        if (exit) {
            // we use SYN_CONFIG to signal that we need to exit the
            // main loop.
            //LOGV("got empty message: value=%d", event->value);
            LOGV("exit");
            return 0x7FFFFFFF;
        }

        if (got_syn && dev->pendingSensors) {
            LOGV("got syn, picking sensor");
            return pick_sensor(dev, values);
        }
    }
}

/*****************************************************************************/

static int control__close(struct hw_device_t *dev)
{
    struct sensors_control_context_t* ctx =
        (struct sensors_control_context_t*)dev;
    if (ctx) {
        close_akm(ctx);
        close_cm(ctx);
        close_ls(ctx);
        free(ctx);
    }
    return 0;
}

static int data__close(struct hw_device_t *dev)
{
    struct sensors_data_context_t* ctx = (struct sensors_data_context_t*)dev;
    if (ctx) {
        data__data_close(ctx);
        free(ctx);
    }
    return 0;
}


/** Open a new instance of a sensor device using name */
static int open_sensors(const struct hw_module_t* module, const char* name,
        struct hw_device_t** device)
{
    int status = -EINVAL;
    if (!strcmp(name, SENSORS_HARDWARE_CONTROL)) {
        struct sensors_control_context_t *dev;
        dev = malloc(sizeof(*dev));
        memset(dev, 0, sizeof(*dev));
        dev->akmd_fd = -1;
        dev->cmd_fd = -1;
        dev->lsd_fd = -1;
        dev->device.common.tag = HARDWARE_DEVICE_TAG;
        dev->device.common.version = 0;
        dev->device.common.module = module;
        dev->device.common.close = control__close;
        dev->device.open_data_source = control__open_data_source;
        dev->device.activate = control__activate;
        dev->device.set_delay= control__set_delay;
        dev->device.wake = control__wake;
        *device = &dev->device.common;
    } else if (!strcmp(name, SENSORS_HARDWARE_DATA)) {
        struct sensors_data_context_t *dev;
        dev = malloc(sizeof(*dev));
        memset(dev, 0, sizeof(*dev));
        dev->events_fd[0] = -1;
        dev->events_fd[1] = -1;
        dev->events_fd[2] = -1;
        dev->device.common.tag = HARDWARE_DEVICE_TAG;
        dev->device.common.version = 0;
        dev->device.common.module = module;
        dev->device.common.close = data__close;
        dev->device.data_open = data__data_open;
        dev->device.data_close = data__data_close;
        dev->device.poll = data__poll;
        *device = &dev->device.common;
    }
    return status;
}