/**************************************************************************** * drivers/sensors/lis3dsh.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 #if defined(CONFIG_SPI) && defined(CONFIG_LIS3DSH) /**************************************************************************** * Private ****************************************************************************/ struct lis3dsh_sensor_data_s { int16_t x_acc; /* Measurement result for x axis */ int16_t y_acc; /* Measurement result for y axis */ int16_t z_acc; /* Measurement result for z axis */ }; struct lis3dsh_dev_s { FAR struct lis3dsh_dev_s *flink; /* Supports a singly linked list of * drivers */ FAR struct spi_dev_s *spi; /* Pointer to the SPI instance */ FAR struct lis3dsh_config_s *config; /* Pointer to the configuration * of the LIS3DSH sensor */ mutex_t datalock; /* Manages exclusive access to this * structure */ struct lis3dsh_sensor_data_s data; /* The data as measured by the sensor */ struct work_s work; /* The work queue is responsible for * retrieving the data from the * sensor after the arrival of new * data was signalled in an interrupt */ }; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ #ifdef CONFIG_DEBUG_SENSORS_INFO static void lis3dsh_read_register(FAR struct lis3dsh_dev_s *dev, uint8_t const reg_addr, uint8_t *reg_data); #endif static void lis3dsh_write_register(FAR struct lis3dsh_dev_s *dev, uint8_t const reg_addr, uint8_t const reg_data); static void lis3dsh_reset(FAR struct lis3dsh_dev_s *dev); static void lis3dsh_read_measurement_data(FAR struct lis3dsh_dev_s *dev); static void lis3dsh_read_acclerometer_data(FAR struct lis3dsh_dev_s *dev, uint16_t *x_acc, uint16_t *y_acc, uint16_t *z_acc); static int lis3dsh_interrupt_handler(int irq, FAR void *context, FAR void *arg); static void lis3dsh_worker(FAR void *arg); static int lis3dsh_open(FAR struct file *filep); static int lis3dsh_close(FAR struct file *filep); static ssize_t lis3dsh_read(FAR struct file *, FAR char *buffer, size_t buflen); static ssize_t lis3dsh_write(FAR struct file *filep, FAR const char *buffer, size_t buflen); /**************************************************************************** * Private Data ****************************************************************************/ static const struct file_operations g_lis3dsh_fops = { lis3dsh_open, /* open */ lis3dsh_close, /* close */ lis3dsh_read, /* read */ lis3dsh_write, /* write */ }; /* Single linked list to store instances of drivers */ static struct lis3dsh_dev_s *g_lis3dsh_list = NULL; /**************************************************************************** * Private Functions ****************************************************************************/ #ifdef CONFIG_DEBUG_SENSORS_INFO /**************************************************************************** * Name: lis3dsh_read_register ****************************************************************************/ static void lis3dsh_read_register(FAR struct lis3dsh_dev_s *dev, uint8_t const reg_addr, uint8_t * reg_data) { /* Lock the SPI bus so that only one device can access it at the same * time */ SPI_LOCK(dev->spi, true); /* Set CS to low which selects the LIS3DSH */ SPI_SELECT(dev->spi, dev->config->spi_devid, true); /* Transmit the register address from where we want to read - the MSB needs * to be set to indicate the read indication. */ SPI_SEND(dev->spi, reg_addr | 0x80); /* Write an idle byte while receiving the required data */ *reg_data = (uint8_t) (SPI_SEND(dev->spi, 0)); /* Set CS to high which deselects the LIS3DSH */ SPI_SELECT(dev->spi, dev->config->spi_devid, false); /* Unlock the SPI bus */ SPI_LOCK(dev->spi, false); } #endif /**************************************************************************** * Name: lis3dsh_write_register ****************************************************************************/ static void lis3dsh_write_register(FAR struct lis3dsh_dev_s *dev, uint8_t const reg_addr, uint8_t const reg_data) { /* Lock the SPI bus so that only one device can access it at the same * time */ SPI_LOCK(dev->spi, true); /* Set CS to low which selects the LIS3DSH */ SPI_SELECT(dev->spi, dev->config->spi_devid, true); /* Transmit the register address from where we want to read */ SPI_SEND(dev->spi, reg_addr); /* Transmit the content which should be written in the register */ SPI_SEND(dev->spi, reg_data); /* Set CS to high which deselects the LIS3DSH */ SPI_SELECT(dev->spi, dev->config->spi_devid, false); /* Unlock the SPI bus */ SPI_LOCK(dev->spi, false); } /**************************************************************************** * Name: lis3dsh_reset ****************************************************************************/ static void lis3dsh_reset(FAR struct lis3dsh_dev_s *dev) { lis3dsh_write_register(dev, LIS3DSH_CTRL_REG_6, LIS3DSH_CTRL_REG_6_BOOT_BM); up_mdelay(100); } /**************************************************************************** * Name: lis3dsh_read_measurement_data ****************************************************************************/ static void lis3dsh_read_measurement_data(FAR struct lis3dsh_dev_s *dev) { uint16_t x_acc = 0; uint16_t y_acc = 0; uint16_t z_acc = 0; int ret; /* Read acclerometer data */ lis3dsh_read_acclerometer_data(dev, &x_acc, &y_acc, &z_acc); /* Acquire the mutex before the data is copied */ ret = nxmutex_lock(&dev->datalock); if (ret < 0) { snerr("ERROR: Could not acquire dev->datalock: %d\n", ret); return; } /* Copy retrieve data to internal data structure */ dev->data.x_acc = (int16_t)x_acc; dev->data.y_acc = (int16_t)y_acc; dev->data.z_acc = (int16_t)z_acc; /* Give back the mutex */ nxmutex_unlock(&dev->datalock); /* Feed sensor data to entropy pool */ add_sensor_randomness((x_acc << 16) ^ (y_acc << 8) ^ (z_acc << 0)); } /**************************************************************************** * Name: lis3dsh_read_acclerometer_data ****************************************************************************/ static void lis3dsh_read_acclerometer_data(FAR struct lis3dsh_dev_s *dev, uint16_t * x_acc, uint16_t * y_acc, uint16_t * z_acc) { /* Lock the SPI bus so that only one device can access it at the same * time */ SPI_LOCK(dev->spi, true); /* Set CS to low which selects the LIS3DSH */ SPI_SELECT(dev->spi, dev->config->spi_devid, true); /* Transmit the register address from where we want to start reading * 0x80 -> MSB is set -> Read Indication. */ SPI_SEND(dev->spi, (LIS3DSH_OUT_X_L_REG | 0x80)); /* RX */ *x_acc = ((uint16_t) (SPI_SEND(dev->spi, 0)) << 0); /* LSB */ *x_acc |= ((uint16_t) (SPI_SEND(dev->spi, 0)) << 8); /* MSB */ *y_acc = ((uint16_t) (SPI_SEND(dev->spi, 0)) << 0); /* LSB */ *y_acc |= ((uint16_t) (SPI_SEND(dev->spi, 0)) << 8); /* MSB */ *z_acc = ((uint16_t) (SPI_SEND(dev->spi, 0)) << 0); /* LSB */ *z_acc |= ((uint16_t) (SPI_SEND(dev->spi, 0)) << 8); /* MSB */ /* Set CS to high which deselects the LIS3DSH */ SPI_SELECT(dev->spi, dev->config->spi_devid, false); /* Unlock the SPI bus */ SPI_LOCK(dev->spi, false); } /**************************************************************************** * Name: lis3dsh_interrupt_handler ****************************************************************************/ static int lis3dsh_interrupt_handler(int irq, FAR void *context, FAR void *arg) { /* This function should be called upon a rising edge on the LIS3DSH new * data interrupt pin since it signals that new data has been measured. */ FAR struct lis3dsh_dev_s *priv = NULL; int ret; /* Find out which device caused the interrupt */ for (priv = g_lis3dsh_list; priv && priv->config->irq != irq; priv = priv->flink) { } DEBUGASSERT(priv != NULL); /* Task the worker with retrieving the latest sensor data. We should not do * this in a interrupt since it might take too long. Also we cannot lock * the SPI bus from within an interrupt. */ if (work_available(&priv->work)) { ret = work_queue(HPWORK, &priv->work, lis3dsh_worker, priv, 0); if (ret < 0) { snerr("ERROR: Failed to queue work: %d\n", ret); return ret; } } return OK; } /**************************************************************************** * Name: lis3dsh_worker ****************************************************************************/ static void lis3dsh_worker(FAR void *arg) { FAR struct lis3dsh_dev_s *priv = (FAR struct lis3dsh_dev_s *)(arg); DEBUGASSERT(priv != NULL); /* Read out the latest sensor data */ lis3dsh_read_measurement_data(priv); } /**************************************************************************** * Name: lis3dsh_open ****************************************************************************/ static int lis3dsh_open(FAR struct file *filep) { FAR struct inode *inode = filep->f_inode; FAR struct lis3dsh_dev_s *priv = inode->i_private; DEBUGASSERT(priv != NULL); /* Perform a reset */ lis3dsh_reset(priv); /* Enable - the full scale range (FS = +/- 16 g) */ lis3dsh_write_register(priv, LIS3DSH_CTRL_REG_5, LIS3DSH_CTRL_REG_5_FSCALE_2_BM); /* Enable - Auto increment of address when reading multiple bytes */ lis3dsh_write_register(priv, LIS3DSH_CTRL_REG_6, LIS3DSH_CTRL_REG_6_ADD_INC_BM); /* Enable - Measurement of X-, Y-, and Z-axis - Block data update for * accelerating data This should prevent race conditions when reading * sensor data - fastest output data rate (ODR = 1600 Hz). */ lis3dsh_write_register(priv, LIS3DSH_CTRL_REG_4, LIS3DSH_CTRL_REG_4_XEN_BM | LIS3DSH_CTRL_REG_4_YEN_BM | LIS3DSH_CTRL_REG_4_ZEN_BM | LIS3DSH_CTRL_REG_4_BDU_BM | LIS3DSH_CTRL_REG_4_ODR_3_BM | LIS3DSH_CTRL_REG_4_ODR_0_BM); /* Enable - DRDY signal enable to INT 1 */ lis3dsh_write_register(priv, LIS3DSH_CTRL_REG_3, LIS3DSH_CTRL_REG_3_DR_EN_BM | LIS3DSH_CTRL_REG_3_IEA_BM | LIS3DSH_CTRL_REG_3_IEL_BM | LIS3DSH_CTRL_REG_3_INT1_EN_BM); /* Read back the content of all control registers for debug purposes */ #ifdef CONFIG_DEBUG_SENSORS_INFO { uint8_t reg_content = 0; lis3dsh_read_register(priv, LIS3DSH_CTRL_REG_1, ®_content); sninfo("LIS3DSH_CTRL_REG_1 = %04x\n", reg_content); lis3dsh_read_register(priv, LIS3DSH_CTRL_REG_2, ®_content); sninfo("LIS3DSH_CTRL_REG_2 = %04x\n", reg_content); lis3dsh_read_register(priv, LIS3DSH_CTRL_REG_3, ®_content); sninfo("LIS3DSH_CTRL_REG_3 = %04x\n", reg_content); lis3dsh_read_register(priv, LIS3DSH_CTRL_REG_4, ®_content); sninfo("LIS3DSH_CTRL_REG_4 = %04x\n", reg_content); lis3dsh_read_register(priv, LIS3DSH_CTRL_REG_5, ®_content); sninfo("LIS3DSH_CTRL_REG_5 = %04x\n", reg_content); lis3dsh_read_register(priv, LIS3DSH_CTRL_REG_6, ®_content); sninfo("LIS3DSH_CTRL_REG_6 = %04x\n", reg_content); lis3dsh_read_register(priv, LIS3DSH_STATUS_REG, ®_content); sninfo("STATUS_REG = %04x\n", reg_content); } #endif return OK; } /**************************************************************************** * Name: lis3dsh_close ****************************************************************************/ static int lis3dsh_close(FAR struct file *filep) { FAR struct inode *inode = filep->f_inode; FAR struct lis3dsh_dev_s *priv = inode->i_private; DEBUGASSERT(priv != NULL); /* Perform a reset */ lis3dsh_reset(priv); return OK; } /**************************************************************************** * Name: lis3dsh_read ****************************************************************************/ static ssize_t lis3dsh_read(FAR struct file *filep, FAR char *buffer, size_t buflen) { FAR struct inode *inode = filep->f_inode; FAR struct lis3dsh_dev_s *priv = inode->i_private; FAR struct lis3dsh_sensor_data_s *data; int ret; DEBUGASSERT(priv != NULL); /* Check if enough memory was provided for the read call */ if (buflen < sizeof(FAR struct lis3dsh_sensor_data_s)) { snerr("ERROR: Not enough memory for reading out a sensor data" " sample\n"); return -ENOSYS; } /* Acquire the mutex before the data is copied */ ret = nxmutex_lock(&priv->datalock); if (ret < 0) { snerr("ERROR: Could not acquire priv->datalock: %d\n", ret); return ret; } /* Copy the sensor data into the buffer */ data = (FAR struct lis3dsh_sensor_data_s *)buffer; memset(data, 0, sizeof(FAR struct lis3dsh_sensor_data_s)); data->x_acc = priv->data.x_acc; data->y_acc = priv->data.y_acc; data->z_acc = priv->data.z_acc; /* Give back the mutex */ nxmutex_unlock(&priv->datalock); return sizeof(FAR struct lis3dsh_sensor_data_s); } /**************************************************************************** * Name: lis3dsh_write ****************************************************************************/ static ssize_t lis3dsh_write(FAR struct file *filep, FAR const char *buffer, size_t buflen) { return -ENOSYS; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: lis3dsh_register * * Description: * Register the LIS3DSH character device as 'devpath' * * Input Parameters: * devpath - The full path to the driver to register. E.g., "/dev/acc0" * spi - An instance of the SPI interface to use to communicate with * LIS3DSH * config - configuration for the LIS3DSH driver. * * Returned Value: * Zero (OK) on success; a negated errno value on failure. * ****************************************************************************/ int lis3dsh_register(FAR const char *devpath, FAR struct spi_dev_s *spi, FAR struct lis3dsh_config_s *config) { FAR struct lis3dsh_dev_s *priv; int ret; /* Sanity check */ DEBUGASSERT(spi != NULL); DEBUGASSERT(config != NULL); /* Initialize the LIS3DSH device structure */ priv = kmm_malloc(sizeof(struct lis3dsh_dev_s)); if (priv == NULL) { snerr("ERROR: Failed to allocate instance\n"); return -ENOMEM; } priv->spi = spi; priv->config = config; priv->work.worker = NULL; nxmutex_init(&priv->datalock); /* Initialize sensor data access mutex */ /* Setup SPI frequency and mode */ SPI_SETFREQUENCY(spi, LIS3DSH_SPI_FREQUENCY); SPI_SETMODE(spi, LIS3DSH_SPI_MODE); /* Register the character driver */ ret = register_driver(devpath, &g_lis3dsh_fops, 0666, priv); if (ret < 0) { snerr("ERROR: Failed to register driver: %d\n", ret); nxmutex_destroy(&priv->datalock); kmm_free(priv); return ret; } /* Since we support multiple LIS3DSH devices, we will need to add this new * instance to a list of device instances so that it can be found by the * interrupt handler based on the received IRQ number. */ priv->flink = g_lis3dsh_list; g_lis3dsh_list = priv; /* Attach the interrupt handler */ ret = priv->config->attach(priv->config, &lis3dsh_interrupt_handler); if (ret < 0) { snerr("ERROR: Failed to attach interrupt: %d\n", ret); nxmutex_destroy(&priv->datalock); kmm_free(priv); return ret; } return OK; } #endif /* CONFIG_SPI && CONFIG_LIS3DSH */