/* * 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;}从源码找到的一个例子，写的很优雅，不知道HAL怎么写的同学可以好好学习一下：
主要结构分析：
传感器模块封装：
/** * Every hardware module must have a data structure named HAL_MODULE_INFO_SYM * and the fields of this data structure must begin with hw_module_t * followed by module specific information. */struct sensors_module_t { struct hw_module_t common; /** * Enumerate all available sensors. The list is returned in "list". * @return number of sensors in the list */ int (*get_sensors_list)(struct sensors_module_t* module, struct sensor_t const** list);};传感器封装：
struct sensor_t { /* name of this sensors */ const char* name; /* vendor of the hardware part */ const char* vendor; /* version of the hardware part + driver. The value of this field is * left to the implementation and doesn't have to be monotonically * increasing. */ int version; /* handle that identifies this sensors. This handle is used to activate * and deactivate this sensor. The value of the handle must be 8 bits * in this version of the API. */ int handle; /* this sensor's type. */ int type; /* maximaum range of this sensor's value in SI units */ float maxRange; /* smallest difference between two values reported by this sensor */ float resolution; /* rough estimate of this sensor's power consumption in mA */ float power; /* minimum delay allowed between events in microseconds. A value of zero * means that this sensor doesn't report events at a constant rate, but * rather only when a new data is available */ int32_t minDelay; /* reserved fields, must be zero */ void* reserved[8];};
与这两个数据相关的操作，主要是提供对外的接口
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};关键操作有open_sensors
/** 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;}
设备数据的基类
/** * Every device data structure must begin with hw_device_t * followed by module specific public methods and attributes. */typedef struct hw_device_t { /** tag must be initialized to HARDWARE_DEVICE_TAG */ uint32_t tag; /** version number for hw_device_t */ uint32_t version; /** reference to the module this device belongs to */ struct hw_module_t* module; /** padding reserved for future use */ uint32_t reserved[12]; /** Close this device */ int (*close)(struct hw_device_t* device);} hw_device_t;传输的函数中name参数为控制或数据（control，data）。
控制设备的上下文
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;};其中，sensors_control_device_t 为传感器控制设备提供操作的方法
struct sensors_control_device_t { struct hw_device_t common; native_handle_t* (*open_data_source)(struct sensors_control_device_t *dev); int (*close_data_source)(struct sensors_control_device_t *dev); int (*activate)(struct sensors_control_device_t *dev, int handle, int enabled); int (*set_delay)(struct sensors_control_device_t *dev, int32_t ms); int (*wake)(struct sensors_control_device_t *dev);};设备数据上下文
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;};
其中，sensors_data_device_t 为传感器的数据操作提供方法
struct sensors_data_device_t { struct hw_device_t common; int (*data_open)(struct sensors_data_device_t *dev, native_handle_t* nh); int (*data_close)(struct sensors_data_device_t *dev); int (*poll)(struct sensors_data_device_t *dev, sensors_data_t* data);};
有了以上的数据和控制设备上下文，就可以将驱动层的函数填充到设备山下文中去，主要的函数有如下
control__wake， control__set_delay，control__activate，control__open_data_source，control__close， data__close，data__data_open，data__data_close，data__poll。
经过上述封装，就将传感器的驱动层的操作封装了，以便给上层的framwork层调用。