/**************************************************************************** * drivers/sensors/sensor.c * * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. The * ASF licenses this file to you 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. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include #include /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /* Device naming ************************************************************/ #define ROUNDUP(x, esize) ((x + (esize - 1)) / (esize)) * (esize) #define DEVNAME_FMT "/dev/sensor/%s%s%d" #define DEVNAME_MAX 64 #define DEVNAME_UNCAL "_uncal" /**************************************************************************** * Private Types ****************************************************************************/ /* This structure describes sensor info */ struct sensor_info { uint8_t esize; FAR char *name; }; /* This structure describes the state of the upper half driver */ struct sensor_upperhalf_s { /* poll structures of threads waiting for driver events. */ FAR struct pollfd *fds[CONFIG_SENSORS_NPOLLWAITERS]; FAR struct sensor_lowerhalf_s *lower; /* the handle of lower half driver */ struct circbuf_s buffer; /* The circular buffer of sensor device */ uint8_t esize; /* The element size of circular buffer */ uint8_t crefs; /* Number of times the device has been opened */ sem_t exclsem; /* Manages exclusive access to file operations */ sem_t buffersem; /* Wakeup user waiting for data in circular buffer */ bool enabled; /* The status of sensor enable or disable */ unsigned int interval; /* The sample interval for sensor, in us */ unsigned int latency; /* The batch latency for sensor, in us */ }; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ static void sensor_pollnotify(FAR struct sensor_upperhalf_s *upper, pollevent_t eventset); static int sensor_open(FAR struct file *filep); static int sensor_close(FAR struct file *filep); static ssize_t sensor_read(FAR struct file *filep, FAR char *buffer, size_t buflen); static int sensor_ioctl(FAR struct file *filep, int cmd, unsigned long arg); static int sensor_poll(FAR struct file *filep, FAR struct pollfd *fds, bool setup); /**************************************************************************** * Private Data ****************************************************************************/ static const struct sensor_info g_sensor_info[] = { {0, NULL}, {sizeof(struct sensor_event_accel), "accel"}, {sizeof(struct sensor_event_mag), "mag"}, {sizeof(struct sensor_event_gyro), "gyro"}, {sizeof(struct sensor_event_light), "light"}, {sizeof(struct sensor_event_baro), "baro"}, {sizeof(struct sensor_event_prox), "prox"}, {sizeof(struct sensor_event_humi), "humi"}, {sizeof(struct sensor_event_temp), "temp"}, {sizeof(struct sensor_event_rgb), "rgb"}, {sizeof(struct sensor_event_hall), "hall"}, {sizeof(struct sensor_event_ir), "ir"}, {sizeof(struct sensor_event_gps), "gps"}, {sizeof(struct sensor_event_uv), "uv"}, {sizeof(struct sensor_event_noise), "noise"}, {sizeof(struct sensor_event_pm25), "pm25"}, {sizeof(struct sensor_event_pm1p0), "pm1p0"}, {sizeof(struct sensor_event_pm10), "pm10"}, {sizeof(struct sensor_event_co2), "co2"}, {sizeof(struct sensor_event_hcho), "hcho"}, {sizeof(struct sensor_event_tvoc), "tvoc"}, {sizeof(struct sensor_event_ph), "ph"}, {sizeof(struct sensor_event_dust), "dust"}, {sizeof(struct sensor_event_hrate), "hrate"}, {sizeof(struct sensor_event_hbeat), "hbeat"}, }; static const struct file_operations g_sensor_fops = { sensor_open, /* open */ sensor_close, /* close */ sensor_read, /* read */ NULL, /* write */ NULL, /* seek */ sensor_ioctl, /* ioctl */ sensor_poll /* poll */ }; /**************************************************************************** * Private Functions ****************************************************************************/ static void sensor_pollnotify(FAR struct sensor_upperhalf_s *upper, pollevent_t eventset) { FAR struct pollfd *fd; int semcount; int i; for (i = 0; i < CONFIG_SENSORS_NPOLLWAITERS; i++) { fd = upper->fds[i]; if (fd) { fd->revents |= (fd->events & eventset); if (fd->revents != 0) { sninfo("Report events: %02x\n", fd->revents); nxsem_get_value(fd->sem, &semcount); if (semcount < 1) { nxsem_post(fd->sem); } } } } } static int sensor_open(FAR struct file *filep) { FAR struct inode *inode = filep->f_inode; FAR struct sensor_upperhalf_s *upper = inode->i_private; FAR struct sensor_lowerhalf_s *lower = upper->lower; uint8_t tmp; int ret; ret = nxsem_wait(&upper->exclsem); if (ret < 0) { return ret; } tmp = upper->crefs + 1; if (tmp == 0) { /* More than 255 opens; uint8_t overflows to zero */ ret = -EMFILE; goto err; } else if (tmp == 1) { /* Initialize sensor buffer */ ret = circbuf_init(&upper->buffer, NULL, lower->buffer_number * upper->esize); if (ret < 0) { goto err; } } upper->crefs = tmp; err: nxsem_post(&upper->exclsem); return ret; } static int sensor_close(FAR struct file *filep) { FAR struct inode *inode = filep->f_inode; FAR struct sensor_upperhalf_s *upper = inode->i_private; FAR struct sensor_lowerhalf_s *lower = upper->lower; int ret; ret = nxsem_wait(&upper->exclsem); if (ret < 0) { return ret; } if (--upper->crefs <= 0 && upper->enabled) { ret = lower->ops->activate ? lower->ops->activate(lower, false) : -ENOTSUP; if (ret >= 0) { upper->enabled = false; circbuf_uninit(&upper->buffer); } } nxsem_post(&upper->exclsem); return ret; } static ssize_t sensor_read(FAR struct file *filep, FAR char *buffer, size_t len) { FAR struct inode *inode = filep->f_inode; FAR struct sensor_upperhalf_s *upper = inode->i_private; FAR struct sensor_lowerhalf_s *lower = upper->lower; ssize_t ret; if (!buffer || !len) { return -EINVAL; } ret = nxsem_wait(&upper->exclsem); if (ret < 0) { return ret; } if (lower->ops->fetch) { if (!(filep->f_oflags & O_NONBLOCK)) { nxsem_post(&upper->exclsem); ret = nxsem_wait_uninterruptible(&upper->buffersem); if (ret < 0) { return ret; } ret = nxsem_wait(&upper->exclsem); if (ret < 0) { return ret; } } else if (!upper->enabled) { ret = -EAGAIN; goto out; } ret = lower->ops->fetch(lower, buffer, len); } else { /* We must make sure that when the semaphore is equal to 1, there must * be events available in the buffer, so we use a while statement to * synchronize this case that other read operations consume events * that have just entered the buffer. */ while (circbuf_is_empty(&upper->buffer)) { if (filep->f_oflags & O_NONBLOCK) { ret = -EAGAIN; goto out; } else { nxsem_post(&upper->exclsem); ret = nxsem_wait_uninterruptible(&upper->buffersem); if (ret < 0) { return ret; } ret = nxsem_wait(&upper->exclsem); if (ret < 0) { return ret; } } } ret = circbuf_read(&upper->buffer, buffer, len); /* Release some buffer space when current mode isn't batch mode * and last mode is batch mode, and the number of bytes available * in buffer is less than the number of bytes origin. */ uint32_t buffer_size = lower->buffer_number * upper->esize; if (upper->latency == 0 && circbuf_size(&upper->buffer) > buffer_size && circbuf_used(&upper->buffer) <= buffer_size) { ret = circbuf_resize(&upper->buffer, buffer_size); } } out: nxsem_post(&upper->exclsem); return ret; } static int sensor_ioctl(FAR struct file *filep, int cmd, unsigned long arg) { FAR struct inode *inode = filep->f_inode; FAR struct sensor_upperhalf_s *upper = inode->i_private; FAR struct sensor_lowerhalf_s *lower = upper->lower; FAR unsigned int *val = (unsigned int *)(uintptr_t)arg; int ret; sninfo("cmd=%x arg=%08lx\n", cmd, arg); ret = nxsem_wait(&upper->exclsem); if (ret < 0) { return ret; } switch (cmd) { case SNIOC_ACTIVATE: { if (upper->enabled == !!arg) { break; } ret = lower->ops->activate ? lower->ops->activate(lower, !!arg) : -ENOTSUP; if (ret >= 0) { upper->enabled = !!arg; } } break; case SNIOC_SET_INTERVAL: { if (upper->interval == *val) { break; } ret = lower->ops->set_interval ? lower->ops->set_interval(lower, val) : -ENOTSUP; if (ret >= 0) { upper->interval = *val; } } break; case SNIOC_BATCH: { if (upper->interval == 0) { ret = -EINVAL; break; } if (upper->latency == *val) { break; } ret = lower->ops->batch ? lower->ops->batch(lower, val) : -ENOTSUP; if (ret >= 0) { upper->latency = *val; if (*val != 0) { /* Adjust length of buffer in batch mode */ uint32_t buffer_size = (ROUNDUP(*val, upper->interval) / upper->interval + lower->buffer_number) * upper->esize; ret = circbuf_resize(&upper->buffer, buffer_size); } } } break; case SNIOC_GET_NEVENTBUF: { *val = lower->buffer_number + lower->batch_number; } break; case SNIOC_SET_BUFFER_NUMBER: { if (arg != 0) { lower->buffer_number = arg; ret = circbuf_resize(&upper->buffer, arg * upper->esize); } } break; default: /* Lowerhalf driver process other cmd. */ if (lower->ops->control) { ret = lower->ops->control(lower, cmd, arg); } else { ret = -ENOTTY; } break; } nxsem_post(&upper->exclsem); return ret; } static int sensor_poll(FAR struct file *filep, struct pollfd *fds, bool setup) { FAR struct inode *inode = filep->f_inode; FAR struct sensor_upperhalf_s *upper = inode->i_private; FAR struct sensor_lowerhalf_s *lower = upper->lower; pollevent_t eventset = 0; int semcount; int ret; int i; ret = nxsem_wait(&upper->exclsem); if (ret < 0) { return ret; } if (setup) { for (i = 0; i < CONFIG_SENSORS_NPOLLWAITERS; i++) { if (NULL == upper->fds[i]) { upper->fds[i] = fds; fds->priv = &upper->fds[i]; break; } } /* Don't have enough space to store fds */ if (i == CONFIG_SENSORS_NPOLLWAITERS) { ret = -ENOSPC; goto errout; } if (lower->ops->fetch) { /* Always return POLLIN for fetch data directly(non-block) */ if (filep->f_oflags & O_NONBLOCK) { eventset |= (fds->events & POLLIN); } else { nxsem_get_value(&upper->buffersem, &semcount); if (semcount > 0) { eventset |= (fds->events & POLLIN); } } } else if (!circbuf_is_empty(&upper->buffer)) { eventset |= (fds->events & POLLIN); } if (eventset) { sensor_pollnotify(upper, eventset); } } else if (fds->priv != NULL) { for (i = 0; i < CONFIG_SENSORS_NPOLLWAITERS; i++) { if (fds == upper->fds[i]) { upper->fds[i] = NULL; fds->priv = NULL; break; } } } errout: nxsem_post(&upper->exclsem); return ret; } static void sensor_push_event(FAR void *priv, FAR const void *data, size_t bytes) { FAR struct sensor_upperhalf_s *upper = priv; int semcount; if (!bytes || nxsem_wait(&upper->exclsem) < 0) { return; } circbuf_overwrite(&upper->buffer, data, bytes); sensor_pollnotify(upper, POLLIN); nxsem_get_value(&upper->buffersem, &semcount); if (semcount < 1) { nxsem_post(&upper->buffersem); } nxsem_post(&upper->exclsem); } static void sensor_notify_event(FAR void *priv) { FAR struct sensor_upperhalf_s *upper = priv; int semcount; if (nxsem_wait(&upper->exclsem) < 0) { return; } sensor_pollnotify(upper, POLLIN); nxsem_get_value(&upper->buffersem, &semcount); if (semcount < 1) { nxsem_post(&upper->buffersem); } nxsem_post(&upper->exclsem); } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: sensor_register * * Description: * This function binds an instance of a "lower half" Sensor driver with the * "upper half" Sensor device and registers that device so that can be used * by application code. * * We will register the chararter device by node name format based on the * type of sensor. Multiple types of the same type are distinguished by * numbers. eg: accel0, accel1 * * Input Parameters: * dev - A pointer to an instance of lower half sensor driver. This * instance is bound to the sensor driver and must persists as long * as the driver persists. * devno - The user specifies which device of this type, from 0. If the * devno alerady exists, -EEXIST will be returned. * * Returned Value: * OK if the driver was successfully register; A negated errno value is * returned on any failure. * ****************************************************************************/ int sensor_register(FAR struct sensor_lowerhalf_s *lower, int devno) { char path[DEVNAME_MAX]; DEBUGASSERT(lower != NULL); snprintf(path, DEVNAME_MAX, DEVNAME_FMT, g_sensor_info[lower->type].name, lower->uncalibrated ? DEVNAME_UNCAL : "", devno); return sensor_custom_register(lower, path, g_sensor_info[lower->type].esize); } /**************************************************************************** * Name: sensor_custom_register * * Description: * This function binds an instance of a "lower half" Sensor driver with the * "upper half" Sensor device and registers that device so that can be used * by application code. * * You can register the character device type by specific path and esize. * This API corresponds to the sensor_custom_unregister. * * Input Parameters: * dev - A pointer to an instance of lower half sensor driver. This * instance is bound to the sensor driver and must persists as long * as the driver persists. * path - The user specifies path of device. ex: /dev/sensor/xxx. * esize - The element size of intermediate circular buffer. * * Returned Value: * OK if the driver was successfully register; A negated errno value is * returned on any failure. * ****************************************************************************/ int sensor_custom_register(FAR struct sensor_lowerhalf_s *lower, FAR const char *path, uint8_t esize) { FAR struct sensor_upperhalf_s *upper; int ret = -EINVAL; DEBUGASSERT(lower != NULL); if (lower->type >= SENSOR_TYPE_COUNT || !esize) { snerr("ERROR: type is invalid\n"); return ret; } /* Allocate the upper-half data structure */ upper = kmm_zalloc(sizeof(struct sensor_upperhalf_s)); if (!upper) { snerr("ERROR: Allocation failed\n"); return -ENOMEM; } /* Initialize the upper-half data structure */ upper->lower = lower; upper->esize = esize; nxsem_init(&upper->exclsem, 0, 1); nxsem_init(&upper->buffersem, 0, 0); nxsem_set_protocol(&upper->buffersem, SEM_PRIO_NONE); /* Bind the lower half data structure member */ lower->priv = upper; if (!lower->ops->fetch) { if (!lower->buffer_number) { lower->buffer_number = 1; } lower->push_event = sensor_push_event; } else { lower->notify_event = sensor_notify_event; lower->buffer_number = 0; } sninfo("Registering %s\n", path); ret = register_driver(path, &g_sensor_fops, 0666, upper); if (ret) { goto drv_err; } return ret; drv_err: nxsem_destroy(&upper->exclsem); nxsem_destroy(&upper->buffersem); kmm_free(upper); return ret; } /**************************************************************************** * Name: sensor_unregister * * Description: * This function unregister character node and release all resource about * upper half driver. * * Input Parameters: * dev - A pointer to an instance of lower half sensor driver. This * instance is bound to the sensor driver and must persists as long * as the driver persists. * devno - The user specifies which device of this type, from 0. ****************************************************************************/ void sensor_unregister(FAR struct sensor_lowerhalf_s *lower, int devno) { char path[DEVNAME_MAX]; snprintf(path, DEVNAME_MAX, DEVNAME_FMT, g_sensor_info[lower->type].name, lower->uncalibrated ? DEVNAME_UNCAL : "", devno); sensor_custom_unregister(lower, path); } /**************************************************************************** * Name: sensor_custom_unregister * * Description: * This function unregister character node and release all resource about * upper half driver. This API corresponds to the sensor_custom_register. * * Input Parameters: * dev - A pointer to an instance of lower half sensor driver. This * instance is bound to the sensor driver and must persists as long * as the driver persists. * path - The user specifies path of device, ex: /dev/sensor/xxx ****************************************************************************/ void sensor_custom_unregister(FAR struct sensor_lowerhalf_s *lower, FAR const char *path) { FAR struct sensor_upperhalf_s *upper; DEBUGASSERT(lower != NULL); DEBUGASSERT(lower->priv != NULL); upper = lower->priv; sninfo("UnRegistering %s\n", path); unregister_driver(path); nxsem_destroy(&upper->exclsem); nxsem_destroy(&upper->buffersem); kmm_free(upper); }