diff options
Diffstat (limited to 'modules/sensors/multihal.cpp')
| -rw-r--r-- | modules/sensors/multihal.cpp | 586 |
1 files changed, 586 insertions, 0 deletions
diff --git a/modules/sensors/multihal.cpp b/modules/sensors/multihal.cpp new file mode 100644 index 0000000..a145c37 --- /dev/null +++ b/modules/sensors/multihal.cpp @@ -0,0 +1,586 @@ +/* + * Copyright (C) 2013 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. + */ + +#include <hardware/sensors.h> +#include <fcntl.h> +#include <errno.h> +#include <dirent.h> +#include <math.h> +#include <poll.h> +#include <pthread.h> +#include <cutils/atomic.h> + +#define LOG_NDEBUG 1 +#include <cutils/log.h> + +#include <vector> +#include <map> + +#include <stdio.h> +#include <dlfcn.h> +#include <SensorEventQueue.h> + + +static const char* CONFIG_FILENAME = "/system/etc/sensors/hals.conf"; +static const char* LEGAL_SUBHAL_PATH_PREFIX = "/system/lib/hw/"; +static const int MAX_CONF_LINE_LENGTH = 1024; + +static pthread_mutex_t init_modules_mutex = PTHREAD_MUTEX_INITIALIZER; +static pthread_mutex_t init_sensors_mutex = PTHREAD_MUTEX_INITIALIZER; + +// This mutex is shared by all queues +static pthread_mutex_t queue_mutex = PTHREAD_MUTEX_INITIALIZER; + +// Used to pause the multihal poll(). Broadcasted by sub-polling tasks if waiting_for_data. +static pthread_cond_t data_available_cond = PTHREAD_COND_INITIALIZER; +bool waiting_for_data = false; + +/* + * Vector of sub modules, whose indexes are referred to ni this file as module_index. + */ +static std::vector<hw_module_t *> *sub_hw_modules = NULL; + +/* + * Comparable class that globally identifies a sensor, by module index and local handle. + * A module index is the module's index in sub_hw_modules. + * A local handle is the handle the sub-module assigns to a sensor. + */ +struct FullHandle { + int moduleIndex; + int localHandle; + + bool operator<(const FullHandle &that) const { + if (moduleIndex < that.moduleIndex) { + return true; + } + if (moduleIndex > that.moduleIndex) { + return false; + } + return localHandle < that.localHandle; + } + + bool operator==(const FullHandle &that) const { + return moduleIndex == that.moduleIndex && localHandle == that.localHandle; + } +}; + +std::map<int, FullHandle> global_to_full; +std::map<FullHandle, int> full_to_global; +int next_global_handle = 1; + +static int assign_global_handle(int module_index, int local_handle) { + int global_handle = next_global_handle++; + FullHandle full_handle; + full_handle.moduleIndex = module_index; + full_handle.localHandle = local_handle; + full_to_global[full_handle] = global_handle; + global_to_full[global_handle] = full_handle; + return global_handle; +} + +static int get_local_handle(int global_handle) { + return global_to_full[global_handle].localHandle; +} + +static int get_module_index(int global_handle) { + FullHandle f = global_to_full[global_handle]; + ALOGV("FullHandle for global_handle %d: moduleIndex %d, localHandle %d", + global_handle, f.moduleIndex, f.localHandle); + return f.moduleIndex; +} + +static const int SENSOR_EVENT_QUEUE_CAPACITY = 20; + +struct TaskContext { + sensors_poll_device_t* device; + SensorEventQueue* queue; +}; + +void *writerTask(void* ptr) { + ALOGV("writerTask STARTS"); + TaskContext* ctx = (TaskContext*)ptr; + sensors_poll_device_t* device = ctx->device; + SensorEventQueue* queue = ctx->queue; + sensors_event_t* buffer; + int eventsPolled; + while (1) { + pthread_mutex_lock(&queue_mutex); + if (queue->waitForSpace(&queue_mutex)) { + ALOGV("writerTask waited for space"); + } + int bufferSize = queue->getWritableRegion(SENSOR_EVENT_QUEUE_CAPACITY, &buffer); + // Do blocking poll outside of lock + pthread_mutex_unlock(&queue_mutex); + + ALOGV("writerTask before poll() - bufferSize = %d", bufferSize); + eventsPolled = device->poll(device, buffer, bufferSize); + ALOGV("writerTask poll() got %d events.", eventsPolled); + if (eventsPolled == 0) { + continue; + } + pthread_mutex_lock(&queue_mutex); + queue->markAsWritten(eventsPolled); + ALOGV("writerTask wrote %d events", eventsPolled); + if (waiting_for_data) { + ALOGV("writerTask - broadcast data_available_cond"); + pthread_cond_broadcast(&data_available_cond); + } + pthread_mutex_unlock(&queue_mutex); + } + // never actually returns + return NULL; +} + +/* + * Cache of all sensors, with original handles replaced by global handles. + * This will be handled to get_sensors_list() callers. + */ +static struct sensor_t const* global_sensors_list = NULL; +static int global_sensors_count = -1; + +/* + * Extends a sensors_poll_device_1 by including all the sub-module's devices. + */ +struct sensors_poll_context_t { + /* + * This is the device that SensorDevice.cpp uses to make API calls + * to the multihal, which fans them out to sub-HALs. + */ + sensors_poll_device_1 proxy_device; // must be first + + void addSubHwDevice(struct hw_device_t*); + + int activate(int handle, int enabled); + int setDelay(int handle, int64_t ns); + int poll(sensors_event_t* data, int count); + int batch(int handle, int flags, int64_t period_ns, int64_t timeout); + int flush(int handle); + int close(); + + std::vector<hw_device_t*> sub_hw_devices; + std::vector<SensorEventQueue*> queues; + std::vector<pthread_t> threads; + int nextReadIndex; + + sensors_poll_device_t* get_v0_device_by_handle(int global_handle); + sensors_poll_device_1_t* get_v1_device_by_handle(int global_handle); + int get_device_version_by_handle(int global_handle); + + void copy_event_remap_handle(sensors_event_t* src, sensors_event_t* dest, int sub_index); +}; + +void sensors_poll_context_t::addSubHwDevice(struct hw_device_t* sub_hw_device) { + ALOGV("addSubHwDevice"); + this->sub_hw_devices.push_back(sub_hw_device); + + SensorEventQueue *queue = new SensorEventQueue(SENSOR_EVENT_QUEUE_CAPACITY); + this->queues.push_back(queue); + + TaskContext* taskContext = new TaskContext(); + taskContext->device = (sensors_poll_device_t*) sub_hw_device; + taskContext->queue = queue; + + pthread_t writerThread; + pthread_create(&writerThread, NULL, writerTask, taskContext); + this->threads.push_back(writerThread); +} + +sensors_poll_device_t* sensors_poll_context_t::get_v0_device_by_handle(int handle) { + int sub_index = get_module_index(handle); + return (sensors_poll_device_t*) this->sub_hw_devices[sub_index]; +} + +sensors_poll_device_1_t* sensors_poll_context_t::get_v1_device_by_handle(int handle) { + int sub_index = get_module_index(handle); + return (sensors_poll_device_1_t*) this->sub_hw_devices[sub_index]; +} + +int sensors_poll_context_t::get_device_version_by_handle(int handle) { + sensors_poll_device_t* v0 = this->get_v0_device_by_handle(handle); + return v0->common.version; +} + +int sensors_poll_context_t::activate(int handle, int enabled) { + ALOGV("activate"); + sensors_poll_device_t* v0 = this->get_v0_device_by_handle(handle); + int retval = v0->activate(v0, get_local_handle(handle), enabled); + ALOGV("retval %d", retval); + return retval; +} + +int sensors_poll_context_t::setDelay(int handle, int64_t ns) { + ALOGV("setDelay"); + sensors_poll_device_t* v0 = this->get_v0_device_by_handle(handle); + int retval = v0->setDelay(v0, get_local_handle(handle), ns); + ALOGV("retval %d", retval); + return retval; +} + +void sensors_poll_context_t::copy_event_remap_handle(sensors_event_t* dest, sensors_event_t* src, + int sub_index) { + memcpy(dest, src, sizeof(struct sensors_event_t)); + // A normal event's "sensor" field is a local handle. Convert it to a global handle. + // A meta-data event must have its sensor set to 0, but it has a nested event + // with a local handle that needs to be converted to a global handle. + FullHandle full_handle; + full_handle.moduleIndex = sub_index; + // If it's a metadata event, rewrite the inner payload, not the sensor field. + if (dest->type == SENSOR_TYPE_META_DATA) { + full_handle.localHandle = dest->meta_data.sensor; + dest->meta_data.sensor = full_to_global[full_handle]; + } else { + full_handle.localHandle = dest->sensor; + dest->sensor = full_to_global[full_handle]; + } +} + +int sensors_poll_context_t::poll(sensors_event_t *data, int maxReads) { + ALOGV("poll"); + int empties = 0; + int queueCount = (int)this->queues.size(); + int eventsRead = 0; + + pthread_mutex_lock(&queue_mutex); + while (eventsRead == 0) { + while (empties < queueCount && eventsRead < maxReads) { + SensorEventQueue* queue = this->queues.at(this->nextReadIndex); + sensors_event_t* event = queue->peek(); + if (event == NULL) { + empties++; + } else { + empties = 0; + this->copy_event_remap_handle(&data[eventsRead++], event, nextReadIndex); + queue->dequeue(); + } + this->nextReadIndex = (this->nextReadIndex + 1) % queueCount; + } + if (eventsRead == 0) { + // The queues have been scanned and none contain data, so wait. + ALOGV("poll stopping to wait for data"); + waiting_for_data = true; + pthread_cond_wait(&data_available_cond, &queue_mutex); + waiting_for_data = false; + empties = 0; + } + } + pthread_mutex_unlock(&queue_mutex); + ALOGV("poll returning %d events.", eventsRead); + + return eventsRead; +} + +int sensors_poll_context_t::batch(int handle, int flags, int64_t period_ns, int64_t timeout) { + ALOGV("batch"); + int retval = -EINVAL; + int version = this->get_device_version_by_handle(handle); + if (version >= SENSORS_DEVICE_API_VERSION_1_0) { + sensors_poll_device_1_t* v1 = this->get_v1_device_by_handle(handle); + retval = v1->batch(v1, get_local_handle(handle), flags, period_ns, timeout); + } + ALOGV("retval %d", retval); + return retval; +} + +int sensors_poll_context_t::flush(int handle) { + ALOGV("flush"); + int retval = -EINVAL; + int version = this->get_device_version_by_handle(handle); + if (version >= SENSORS_DEVICE_API_VERSION_1_0) { + sensors_poll_device_1_t* v1 = this->get_v1_device_by_handle(handle); + retval = v1->flush(v1, get_local_handle(handle)); + } + ALOGV("retval %d", retval); + return retval; +} + +int sensors_poll_context_t::close() { + ALOGV("close"); + for (std::vector<hw_device_t*>::iterator it = this->sub_hw_devices.begin(); + it != this->sub_hw_devices.end(); it++) { + hw_device_t* dev = *it; + int retval = dev->close(dev); + ALOGV("retval %d", retval); + } + return 0; +} + + +static int device__close(struct hw_device_t *dev) { + sensors_poll_context_t* ctx = (sensors_poll_context_t*) dev; + if (ctx != NULL) { + int retval = ctx->close(); + delete ctx; + } + return 0; +} + +static int device__activate(struct sensors_poll_device_t *dev, int handle, + int enabled) { + sensors_poll_context_t* ctx = (sensors_poll_context_t*) dev; + return ctx->activate(handle, enabled); +} + +static int device__setDelay(struct sensors_poll_device_t *dev, int handle, + int64_t ns) { + sensors_poll_context_t* ctx = (sensors_poll_context_t*) dev; + return ctx->setDelay(handle, ns); +} + +static int device__poll(struct sensors_poll_device_t *dev, sensors_event_t* data, + int count) { + sensors_poll_context_t* ctx = (sensors_poll_context_t*) dev; + return ctx->poll(data, count); +} + +static int device__batch(struct sensors_poll_device_1 *dev, int handle, + int flags, int64_t period_ns, int64_t timeout) { + sensors_poll_context_t* ctx = (sensors_poll_context_t*) dev; + return ctx->batch(handle, flags, period_ns, timeout); +} + +static int device__flush(struct sensors_poll_device_1 *dev, int handle) { + sensors_poll_context_t* ctx = (sensors_poll_context_t*) dev; + return ctx->flush(handle); +} + +static int open_sensors(const struct hw_module_t* module, const char* name, + struct hw_device_t** device); + +static bool starts_with(const char* s, const char* prefix) { + if (s == NULL || prefix == NULL) { + return false; + } + size_t s_size = strlen(s); + size_t prefix_size = strlen(prefix); + return s_size >= prefix_size && strncmp(s, prefix, prefix_size) == 0; +} + +/* + * Adds valid paths from the config file to the vector passed in. + * The vector must not be null. + */ +static void get_so_paths(std::vector<char*> *so_paths) { + FILE *conf_file = fopen(CONFIG_FILENAME, "r"); + if (conf_file == NULL) { + ALOGW("No multihal config file found at %s", CONFIG_FILENAME); + return; + } + ALOGI("Multihal config file found at %s", CONFIG_FILENAME); + char *line = NULL; + size_t len = 0; + int line_count = 0; + while (getline(&line, &len, conf_file) != -1) { + // overwrite trailing eoln with null char + char* pch = strchr(line, '\n'); + if (pch != NULL) { + *pch = '\0'; + } + ALOGV("config file line #%d: '%s'", ++line_count, line); + char *real_path = realpath(line, NULL); + if (starts_with(real_path, LEGAL_SUBHAL_PATH_PREFIX)) { + ALOGI("accepting valid path '%s'", real_path); + char* compact_line = new char[strlen(real_path) + 1]; + strcpy(compact_line, real_path); + so_paths->push_back(compact_line); + } else { + ALOGW("rejecting path '%s' because it does not start with '%s'", + real_path, LEGAL_SUBHAL_PATH_PREFIX); + } + free(real_path); + } + free(line); + fclose(conf_file); + ALOGV("hals.conf contained %d lines", line_count); +} + +/* + * Ensures that the sub-module array is initialized. + * This can be first called from get_sensors_list or from open_sensors. + */ +static void lazy_init_modules() { + pthread_mutex_lock(&init_modules_mutex); + if (sub_hw_modules != NULL) { + pthread_mutex_unlock(&init_modules_mutex); + return; + } + std::vector<char*> *so_paths = new std::vector<char*>(); + get_so_paths(so_paths); + + // dlopen the module files and cache their module symbols in sub_hw_modules + sub_hw_modules = new std::vector<hw_module_t *>(); + dlerror(); // clear any old errors + const char* sym = HAL_MODULE_INFO_SYM_AS_STR; + for (std::vector<char*>::iterator it = so_paths->begin(); it != so_paths->end(); it++) { + char* path = *it; + void* lib_handle = dlopen(path, RTLD_LAZY); + if (lib_handle == NULL) { + ALOGW("dlerror(): %s", dlerror()); + } else { + ALOGI("hal lib was loaded: %s", path); + ALOGV("Opening symbol \"%s\"", sym); + // clear old errors + dlerror(); + struct hw_module_t* module = (hw_module_t*) dlsym(lib_handle, sym); + const char* error; + if ((error = dlerror()) != NULL) { + ALOGW("Error calling dlsym: %s", error); + } else if (module == NULL) { + ALOGW("module == NULL"); + } else { + ALOGI("OK, dlsym()'ed \"%s\"", sym); + sub_hw_modules->push_back(module); + } + } + } + pthread_mutex_unlock(&init_modules_mutex); +} + +/* + * Lazy-initializes global_sensors_count, global_sensors_list, and module_sensor_handles. + */ +static void lazy_init_sensors_list() { + ALOGV("lazy_init_sensors_list"); + pthread_mutex_lock(&init_sensors_mutex); + if (global_sensors_list != NULL) { + // already initialized + pthread_mutex_unlock(&init_sensors_mutex); + ALOGV("lazy_init_sensors_list - early return"); + return; + } + + ALOGV("lazy_init_sensors_list needs to do work"); + lazy_init_modules(); + + // Count all the sensors, then allocate an array of blanks. + global_sensors_count = 0; + const struct sensor_t *subhal_sensors_list; + for (std::vector<hw_module_t*>::iterator it = sub_hw_modules->begin(); + it != sub_hw_modules->end(); it++) { + struct sensors_module_t *module = (struct sensors_module_t*) *it; + global_sensors_count += module->get_sensors_list(module, &subhal_sensors_list); + ALOGV("increased global_sensors_count to %d", global_sensors_count); + } + + // The global_sensors_list is full of consts. + // Manipulate this non-const list, and point the const one to it when we're done. + sensor_t* mutable_sensor_list = new sensor_t[global_sensors_count]; + + // index of the next sensor to set in mutable_sensor_list + int mutable_sensor_index = 0; + int module_index = 0; + + for (std::vector<hw_module_t*>::iterator it = sub_hw_modules->begin(); + it != sub_hw_modules->end(); it++) { + hw_module_t *hw_module = *it; + ALOGV("examine one module"); + // Read the sub-module's sensor list. + struct sensors_module_t *module = (struct sensors_module_t*) hw_module; + int module_sensor_count = module->get_sensors_list(module, &subhal_sensors_list); + ALOGV("the module has %d sensors", module_sensor_count); + + // Copy the HAL's sensor list into global_sensors_list, + // with the handle changed to be a global handle. + for (int i = 0; i < module_sensor_count; i++) { + ALOGV("examining one sensor"); + const struct sensor_t *local_sensor = &subhal_sensors_list[i]; + int local_handle = local_sensor->handle; + memcpy(&mutable_sensor_list[mutable_sensor_index], local_sensor, + sizeof(struct sensor_t)); + + // Overwrite the global version's handle with a global handle. + int global_handle = assign_global_handle(module_index, local_handle); + + mutable_sensor_list[mutable_sensor_index].handle = global_handle; + ALOGI("module_index %d, local_handle %d, global_handle %d", + module_index, local_handle, global_handle); + + mutable_sensor_index++; + } + module_index++; + } + // Set the const static global_sensors_list to the mutable one allocated by this function. + global_sensors_list = mutable_sensor_list; + + pthread_mutex_unlock(&init_sensors_mutex); + ALOGV("end lazy_init_sensors_list"); +} + +static int module__get_sensors_list(struct sensors_module_t* module, + struct sensor_t const** list) { + ALOGV("module__get_sensors_list start"); + lazy_init_sensors_list(); + *list = global_sensors_list; + ALOGV("global_sensors_count: %d", global_sensors_count); + for (int i = 0; i < global_sensors_count; i++) { + ALOGV("sensor type: %d", global_sensors_list[i].type); + } + return global_sensors_count; +} + +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 : "MultiHal Sensor Module", + author : "Google, Inc", + methods : &sensors_module_methods, + dso : NULL, + reserved : {0}, + }, + get_sensors_list : module__get_sensors_list +}; + +static int open_sensors(const struct hw_module_t* hw_module, const char* name, + struct hw_device_t** hw_device_out) { + ALOGI("open_sensors begin..."); + + lazy_init_modules(); + + // Create proxy device, to return later. + sensors_poll_context_t *dev = new sensors_poll_context_t(); + memset(dev, 0, sizeof(sensors_poll_device_1_t)); + dev->proxy_device.common.tag = HARDWARE_DEVICE_TAG; + dev->proxy_device.common.version = SENSORS_DEVICE_API_VERSION_1_0; + dev->proxy_device.common.module = const_cast<hw_module_t*>(hw_module); + dev->proxy_device.common.close = device__close; + dev->proxy_device.activate = device__activate; + dev->proxy_device.setDelay = device__setDelay; + dev->proxy_device.poll = device__poll; + dev->proxy_device.batch = device__batch; + dev->proxy_device.flush = device__flush; + + dev->nextReadIndex = 0; + + // Open() the subhal modules. Remember their devices in a vector parallel to sub_hw_modules. + for (std::vector<hw_module_t*>::iterator it = sub_hw_modules->begin(); + it != sub_hw_modules->end(); it++) { + sensors_module_t *sensors_module = (sensors_module_t*) *it; + struct hw_device_t* sub_hw_device; + int sub_open_result = sensors_module->common.methods->open(*it, name, &sub_hw_device); + dev->addSubHwDevice(sub_hw_device); + } + + // Prepare the output param and return + *hw_device_out = &dev->proxy_device.common; + ALOGI("...open_sensors end"); + return 0; +} |