/* * Copyright (C) 2009 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. */ /* this implements a sensors hardware library for the Android emulator. * the following code should be built as a shared library that will be * placed into /system/lib/hw/sensors.goldfish.so * * it will be loaded by the code in hardware/libhardware/hardware.c * which is itself called from com_android_server_SensorService.cpp */ /* we connect with the emulator through the "sensors" qemud service */ #define SENSORS_SERVICE_NAME "sensors" #define LOG_TAG "QemuSensors" #include <unistd.h> #include <fcntl.h> #include <errno.h> #include <string.h> #include <cutils/log.h> #include <cutils/sockets.h> #include <hardware/sensors.h> #if 0 #define D(...) ALOGD(__VA_ARGS__) #else #define D(...) ((void)0) #endif #define E(...) ALOGE(__VA_ARGS__) #include <hardware/qemud.h> /** SENSOR IDS AND NAMES **/ #define MAX_NUM_SENSORS 8 #define SUPPORTED_SENSORS ((1<<MAX_NUM_SENSORS)-1) #define ID_BASE SENSORS_HANDLE_BASE #define ID_ACCELERATION (ID_BASE+0) #define ID_MAGNETIC_FIELD (ID_BASE+1) #define ID_ORIENTATION (ID_BASE+2) #define ID_TEMPERATURE (ID_BASE+3) #define ID_PROXIMITY (ID_BASE+4) #define ID_LIGHT (ID_BASE+5) #define ID_PRESSURE (ID_BASE+6) #define ID_HUMIDITY (ID_BASE+7) #define SENSORS_ACCELERATION (1 << ID_ACCELERATION) #define SENSORS_MAGNETIC_FIELD (1 << ID_MAGNETIC_FIELD) #define SENSORS_ORIENTATION (1 << ID_ORIENTATION) #define SENSORS_TEMPERATURE (1 << ID_TEMPERATURE) #define SENSORS_PROXIMITY (1 << ID_PROXIMITY) #define SENSORS_LIGHT (1 << ID_LIGHT) #define SENSORS_PRESSURE (1 << ID_PRESSURE) #define SENSORS_HUMIDITY (1 << ID_HUMIDITY) #define ID_CHECK(x) ((unsigned)((x) - ID_BASE) < MAX_NUM_SENSORS) #define SENSORS_LIST \ SENSOR_(ACCELERATION,"acceleration") \ SENSOR_(MAGNETIC_FIELD,"magnetic-field") \ SENSOR_(ORIENTATION,"orientation") \ SENSOR_(TEMPERATURE,"temperature") \ SENSOR_(PROXIMITY,"proximity") \ SENSOR_(LIGHT, "light") \ SENSOR_(PRESSURE, "pressure") \ SENSOR_(HUMIDITY, "humidity") static const struct { const char* name; int id; } _sensorIds[MAX_NUM_SENSORS] = { #define SENSOR_(x,y) { y, ID_##x }, SENSORS_LIST #undef SENSOR_ }; static const char* _sensorIdToName( int id ) { int nn; for (nn = 0; nn < MAX_NUM_SENSORS; nn++) if (id == _sensorIds[nn].id) return _sensorIds[nn].name; return "<UNKNOWN>"; } static int _sensorIdFromName( const char* name ) { int nn; if (name == NULL) return -1; for (nn = 0; nn < MAX_NUM_SENSORS; nn++) if (!strcmp(name, _sensorIds[nn].name)) return _sensorIds[nn].id; return -1; } /* return the current time in nanoseconds */ static int64_t now_ns(void) { struct timespec ts; clock_gettime(CLOCK_MONOTONIC, &ts); return (int64_t)ts.tv_sec * 1000000000 + ts.tv_nsec; } /** SENSORS POLL DEVICE ** ** This one is used to read sensor data from the hardware. ** We implement this by simply reading the data from the ** emulator through the QEMUD channel. **/ typedef struct SensorDevice { struct sensors_poll_device_1 device; sensors_event_t sensors[MAX_NUM_SENSORS]; uint32_t pendingSensors; int64_t timeStart; int64_t timeOffset; uint32_t active_sensors; int fd; pthread_mutex_t lock; } SensorDevice; /* Grab the file descriptor to the emulator's sensors service pipe. * This function returns a file descriptor on success, or -errno on * failure, and assumes the SensorDevice instance's lock is held. * * This is needed because set_delay(), poll() and activate() can be called * from different threads, and poll() is blocking. * * Note that the emulator's sensors service creates a new client for each * connection through qemud_channel_open(), where each client has its own * delay and set of activated sensors. This precludes calling * qemud_channel_open() on each request, because a typical emulated system * will do something like: * * 1) On a first thread, de-activate() all sensors first, then call poll(), * which results in the thread blocking. * * 2) On a second thread, slightly later, call set_delay() then activate() * to enable the acceleration sensor. * * The system expects this to unblock the first thread which will receive * new sensor events after the activate() call in 2). * * This cannot work if both threads don't use the same connection. * * TODO(digit): This protocol is brittle, implement another control channel * for set_delay()/activate()/batch() when supporting HAL 1.3 */ static int sensor_device_get_fd_locked(SensorDevice* dev) { /* Create connection to service on first call */ if (dev->fd < 0) { dev->fd = qemud_channel_open(SENSORS_SERVICE_NAME); if (dev->fd < 0) { int ret = -errno; E("%s: Could not open connection to service: %s", __FUNCTION__, strerror(-ret)); return ret; } } return dev->fd; } /* Send a command to the sensors virtual device. |dev| is a device instance and * |cmd| is a zero-terminated command string. Return 0 on success, or -errno * on failure. */ static int sensor_device_send_command_locked(SensorDevice* dev, const char* cmd) { int fd = sensor_device_get_fd_locked(dev); if (fd < 0) { return fd; } int ret = 0; if (qemud_channel_send(fd, cmd, strlen(cmd)) < 0) { ret = -errno; E("%s(fd=%d): ERROR: %s", __FUNCTION__, fd, strerror(errno)); } return ret; } /* Pick up one pending sensor event. On success, this returns the sensor * id, and sets |*event| accordingly. On failure, i.e. if there are no * pending events, return -EINVAL. * * Note: The device's lock must be acquired. */ static int sensor_device_pick_pending_event_locked(SensorDevice* d, sensors_event_t* event) { uint32_t mask = SUPPORTED_SENSORS & d->pendingSensors; if (mask) { uint32_t i = 31 - __builtin_clz(mask); d->pendingSensors &= ~(1U << i); *event = d->sensors[i]; event->sensor = i; event->version = sizeof(*event); D("%s: %d [%f, %f, %f]", __FUNCTION__, i, event->data[0], event->data[1], event->data[2]); return i; } E("No sensor to return!!! pendingSensors=0x%08x", d->pendingSensors); // we may end-up in a busy loop, slow things down, just in case. usleep(100000); return -EINVAL; } /* Block until new sensor events are reported by the emulator, or if a * 'wake' command is received through the service. On succes, return 0 * and updates the |pendingEvents| and |sensors| fields of |dev|. * On failure, return -errno. * * Note: The device lock must be acquired when calling this function, and * will still be held on return. However, the function releases the * lock temporarily during the blocking wait. */ static int sensor_device_poll_event_locked(SensorDevice* dev) { D("%s: dev=%p", __FUNCTION__, dev); int fd = sensor_device_get_fd_locked(dev); if (fd < 0) { E("%s: Could not get pipe channel: %s", __FUNCTION__, strerror(-fd)); return fd; } // Accumulate pending events into |events| and |new_sensors| mask // until a 'sync' or 'wake' command is received. This also simplifies the // code a bit. uint32_t new_sensors = 0U; sensors_event_t* events = dev->sensors; int64_t event_time = -1; int ret = 0; for (;;) { /* Release the lock since we're going to block on recv() */ pthread_mutex_unlock(&dev->lock); /* read the next event */ char buff[256]; int len = qemud_channel_recv(fd, buff, sizeof(buff) - 1U); /* re-acquire the lock to modify the device state. */ pthread_mutex_lock(&dev->lock); if (len < 0) { ret = -errno; E("%s(fd=%d): Could not receive event data len=%d, errno=%d: %s", __FUNCTION__, fd, len, errno, strerror(errno)); break; } buff[len] = 0; D("%s(fd=%d): received [%s]", __FUNCTION__, fd, buff); /* "wake" is sent from the emulator to exit this loop. */ /* TODO(digit): Is it still needed? */ if (!strcmp((const char*)buff, "wake")) { ret = 0x7FFFFFFF; break; } float params[3]; /* "acceleration:<x>:<y>:<z>" corresponds to an acceleration event */ if (sscanf(buff, "acceleration:%g:%g:%g", params+0, params+1, params+2) == 3) { new_sensors |= SENSORS_ACCELERATION; events[ID_ACCELERATION].acceleration.x = params[0]; events[ID_ACCELERATION].acceleration.y = params[1]; events[ID_ACCELERATION].acceleration.z = params[2]; events[ID_ACCELERATION].type = SENSOR_TYPE_ACCELEROMETER; continue; } /* "orientation:<azimuth>:<pitch>:<roll>" is sent when orientation * changes */ if (sscanf(buff, "orientation:%g:%g:%g", params+0, params+1, params+2) == 3) { new_sensors |= SENSORS_ORIENTATION; events[ID_ORIENTATION].orientation.azimuth = params[0]; events[ID_ORIENTATION].orientation.pitch = params[1]; events[ID_ORIENTATION].orientation.roll = params[2]; events[ID_ORIENTATION].orientation.status = SENSOR_STATUS_ACCURACY_HIGH; events[ID_ORIENTATION].type = SENSOR_TYPE_ORIENTATION; continue; } /* "magnetic:<x>:<y>:<z>" is sent for the params of the magnetic * field */ if (sscanf(buff, "magnetic:%g:%g:%g", params+0, params+1, params+2) == 3) { new_sensors |= SENSORS_MAGNETIC_FIELD; events[ID_MAGNETIC_FIELD].magnetic.x = params[0]; events[ID_MAGNETIC_FIELD].magnetic.y = params[1]; events[ID_MAGNETIC_FIELD].magnetic.z = params[2]; events[ID_MAGNETIC_FIELD].magnetic.status = SENSOR_STATUS_ACCURACY_HIGH; events[ID_MAGNETIC_FIELD].type = SENSOR_TYPE_MAGNETIC_FIELD; continue; } /* "temperature:<celsius>" */ if (sscanf(buff, "temperature:%g", params+0) == 1) { new_sensors |= SENSORS_TEMPERATURE; events[ID_TEMPERATURE].temperature = params[0]; events[ID_TEMPERATURE].type = SENSOR_TYPE_TEMPERATURE; continue; } /* "proximity:<value>" */ if (sscanf(buff, "proximity:%g", params+0) == 1) { new_sensors |= SENSORS_PROXIMITY; events[ID_PROXIMITY].distance = params[0]; events[ID_PROXIMITY].type = SENSOR_TYPE_PROXIMITY; continue; } /* "light:<lux>" */ if (sscanf(buff, "light:%g", params+0) == 1) { new_sensors |= SENSORS_LIGHT; events[ID_LIGHT].light = params[0]; events[ID_LIGHT].type = SENSOR_TYPE_LIGHT; continue; } /* "pressure:<hpa>" */ if (sscanf(buff, "pressure:%g", params+0) == 1) { new_sensors |= SENSORS_PRESSURE; events[ID_PRESSURE].pressure = params[0]; events[ID_PRESSURE].type = SENSOR_TYPE_PRESSURE; continue; } /* "humidity:<percent>" */ if (sscanf(buff, "humidity:%g", params+0) == 1) { new_sensors |= SENSORS_HUMIDITY; events[ID_HUMIDITY].relative_humidity = params[0]; events[ID_HUMIDITY].type = SENSOR_TYPE_RELATIVE_HUMIDITY; continue; } /* "sync:<time>" is sent after a series of sensor events. * where 'time' is expressed in micro-seconds and corresponds * to the VM time when the real poll occured. */ if (sscanf(buff, "sync:%lld", &event_time) == 1) { if (new_sensors) { goto out; } D("huh ? sync without any sensor data ?"); continue; } D("huh ? unsupported command"); } out: if (new_sensors) { /* update the time of each new sensor event. */ dev->pendingSensors |= new_sensors; int64_t t = (event_time < 0) ? 0 : event_time * 1000LL; /* use the time at the first sync: as the base for later * time values */ if (dev->timeStart == 0) { dev->timeStart = now_ns(); dev->timeOffset = dev->timeStart - t; } t += dev->timeOffset; while (new_sensors) { uint32_t i = 31 - __builtin_clz(new_sensors); new_sensors &= ~(1U << i); dev->sensors[i].timestamp = t; } } return ret; } /** SENSORS POLL DEVICE FUNCTIONS **/ static int sensor_device_close(struct hw_device_t* dev0) { SensorDevice* dev = (void*)dev0; // Assume that there are no other threads blocked on poll() if (dev->fd >= 0) { close(dev->fd); dev->fd = -1; } pthread_mutex_destroy(&dev->lock); free(dev); return 0; } /* Return an array of sensor data. This function blocks until there is sensor * related events to report. On success, it will write the events into the * |data| array, which contains |count| items. The function returns the number * of events written into the array, which shall never be greater than |count|. * On error, return -errno code. * * Note that according to the sensor HAL [1], it shall never return 0! * * [1] http://source.android.com/devices/sensors/hal-interface.html */ static int sensor_device_poll(struct sensors_poll_device_t *dev0, sensors_event_t* data, int count) { SensorDevice* dev = (void*)dev0; D("%s: dev=%p data=%p count=%d ", __FUNCTION__, dev, data, count); if (count <= 0) { return -EINVAL; } int result = 0; pthread_mutex_lock(&dev->lock); if (!dev->pendingSensors) { /* Block until there are pending events. Note that this releases * the lock during the blocking call, then re-acquires it before * returning. */ int ret = sensor_device_poll_event_locked(dev); if (ret < 0) { result = ret; goto out; } if (!dev->pendingSensors) { /* 'wake' event received before any sensor data. */ result = -EIO; goto out; } } /* Now read as many pending events as needed. */ int i; for (i = 0; i < count; i++) { if (!dev->pendingSensors) { break; } int ret = sensor_device_pick_pending_event_locked(dev, data); if (ret < 0) { if (!result) { result = ret; } break; } data++; result++; } out: pthread_mutex_unlock(&dev->lock); D("%s: result=%d", __FUNCTION__, result); return result; } static int sensor_device_activate(struct sensors_poll_device_t *dev0, int handle, int enabled) { SensorDevice* dev = (void*)dev0; D("%s: handle=%s (%d) enabled=%d", __FUNCTION__, _sensorIdToName(handle), handle, enabled); /* Sanity check */ if (!ID_CHECK(handle)) { E("%s: bad handle ID", __FUNCTION__); return -EINVAL; } /* Exit early if sensor is already enabled/disabled. */ uint32_t mask = (1U << handle); uint32_t sensors = enabled ? mask : 0; pthread_mutex_lock(&dev->lock); uint32_t active = dev->active_sensors; uint32_t new_sensors = (active & ~mask) | (sensors & mask); uint32_t changed = active ^ new_sensors; int ret = 0; if (changed) { /* Send command to the emulator. */ char command[64]; snprintf(command, sizeof command, "set:%s:%d", _sensorIdToName(handle), enabled != 0); ret = sensor_device_send_command_locked(dev, command); if (ret < 0) { E("%s: when sending command errno=%d: %s", __FUNCTION__, -ret, strerror(-ret)); } else { dev->active_sensors = new_sensors; } } pthread_mutex_unlock(&dev->lock); return ret; } static int sensor_device_set_delay(struct sensors_poll_device_t *dev0, int handle __unused, int64_t ns) { SensorDevice* dev = (void*)dev0; int ms = (int)(ns / 1000000); D("%s: dev=%p delay-ms=%d", __FUNCTION__, dev, ms); char command[64]; snprintf(command, sizeof command, "set-delay:%d", ms); pthread_mutex_lock(&dev->lock); int ret = sensor_device_send_command_locked(dev, command); pthread_mutex_unlock(&dev->lock); if (ret < 0) { E("%s: Could not send command: %s", __FUNCTION__, strerror(-ret)); } return ret; } /** MODULE REGISTRATION SUPPORT ** ** This is required so that hardware/libhardware/hardware.c ** will dlopen() this library appropriately. **/ /* * the following is the list of all supported sensors. * this table is used to build sSensorList declared below * according to which hardware sensors are reported as * available from the emulator (see get_sensors_list below) * * note: numerical values for maxRange/resolution/power for * all sensors but light, pressure and humidity were * taken from the reference AK8976A implementation */ static const struct sensor_t sSensorListInit[] = { { .name = "Goldfish 3-axis Accelerometer", .vendor = "The Android Open Source Project", .version = 1, .handle = ID_ACCELERATION, .type = SENSOR_TYPE_ACCELEROMETER, .maxRange = 2.8f, .resolution = 1.0f/4032.0f, .power = 3.0f, .reserved = {} }, { .name = "Goldfish 3-axis Magnetic field sensor", .vendor = "The Android Open Source Project", .version = 1, .handle = ID_MAGNETIC_FIELD, .type = SENSOR_TYPE_MAGNETIC_FIELD, .maxRange = 2000.0f, .resolution = 1.0f, .power = 6.7f, .reserved = {} }, { .name = "Goldfish Orientation sensor", .vendor = "The Android Open Source Project", .version = 1, .handle = ID_ORIENTATION, .type = SENSOR_TYPE_ORIENTATION, .maxRange = 360.0f, .resolution = 1.0f, .power = 9.7f, .reserved = {} }, { .name = "Goldfish Temperature sensor", .vendor = "The Android Open Source Project", .version = 1, .handle = ID_TEMPERATURE, .type = SENSOR_TYPE_TEMPERATURE, .maxRange = 80.0f, .resolution = 1.0f, .power = 0.0f, .reserved = {} }, { .name = "Goldfish Proximity sensor", .vendor = "The Android Open Source Project", .version = 1, .handle = ID_PROXIMITY, .type = SENSOR_TYPE_PROXIMITY, .maxRange = 1.0f, .resolution = 1.0f, .power = 20.0f, .reserved = {} }, { .name = "Goldfish Light sensor", .vendor = "The Android Open Source Project", .version = 1, .handle = ID_LIGHT, .type = SENSOR_TYPE_LIGHT, .maxRange = 40000.0f, .resolution = 1.0f, .power = 20.0f, .reserved = {} }, { .name = "Goldfish Pressure sensor", .vendor = "The Android Open Source Project", .version = 1, .handle = ID_PRESSURE, .type = SENSOR_TYPE_PRESSURE, .maxRange = 800.0f, .resolution = 1.0f, .power = 20.0f, .reserved = {} }, { .name = "Goldfish Humidity sensor", .vendor = "The Android Open Source Project", .version = 1, .handle = ID_HUMIDITY, .type = SENSOR_TYPE_RELATIVE_HUMIDITY, .maxRange = 100.0f, .resolution = 1.0f, .power = 20.0f, .reserved = {} } }; static struct sensor_t sSensorList[MAX_NUM_SENSORS]; static int sensors__get_sensors_list(struct sensors_module_t* module __unused, struct sensor_t const** list) { int fd = qemud_channel_open(SENSORS_SERVICE_NAME); char buffer[12]; int mask, nn, count; int ret = 0; if (fd < 0) { E("%s: no qemud connection", __FUNCTION__); goto out; } ret = qemud_channel_send(fd, "list-sensors", -1); if (ret < 0) { E("%s: could not query sensor list: %s", __FUNCTION__, strerror(errno)); goto out; } ret = qemud_channel_recv(fd, buffer, sizeof buffer-1); if (ret < 0) { E("%s: could not receive sensor list: %s", __FUNCTION__, strerror(errno)); goto out; } buffer[ret] = 0; /* the result is a integer used as a mask for available sensors */ mask = atoi(buffer); count = 0; for (nn = 0; nn < MAX_NUM_SENSORS; nn++) { if (((1 << nn) & mask) == 0) continue; sSensorList[count++] = sSensorListInit[nn]; } D("%s: returned %d sensors (mask=%d)", __FUNCTION__, count, mask); *list = sSensorList; ret = count; out: if (fd >= 0) { close(fd); } return ret; } static int open_sensors(const struct hw_module_t* module, const char* name, struct hw_device_t* *device) { int status = -EINVAL; D("%s: name=%s", __FUNCTION__, name); if (!strcmp(name, SENSORS_HARDWARE_POLL)) { SensorDevice *dev = malloc(sizeof(*dev)); memset(dev, 0, sizeof(*dev)); dev->device.common.tag = HARDWARE_DEVICE_TAG; dev->device.common.version = SENSORS_DEVICE_API_VERSION_1_0; dev->device.common.module = (struct hw_module_t*) module; dev->device.common.close = sensor_device_close; dev->device.poll = sensor_device_poll; dev->device.activate = sensor_device_activate; dev->device.setDelay = sensor_device_set_delay; dev->fd = -1; pthread_mutex_init(&dev->lock, NULL); *device = &dev->device.common; status = 0; } return status; } static struct hw_module_methods_t sensors_module_methods = { .open = open_sensors }; 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 = "Goldfish SENSORS Module", .author = "The Android Open Source Project", .methods = &sensors_module_methods, }, .get_sensors_list = sensors__get_sensors_list };