/**************************************************************************** * drivers/sensors/l3gd20.c * Character driver for the ST L3GD20 3-Axis gyroscope. * * 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 #include #if defined(CONFIG_SPI) && defined(CONFIG_SENSORS_L3GD20) /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ /**************************************************************************** * Private Types ****************************************************************************/ struct l3gd20_dev_s { FAR struct l3gd20_dev_s *flink; /* Supports a singly linked list of * drivers */ FAR struct spi_dev_s *spi; /* Pointer to the SPI instance */ FAR struct l3gd20_config_s *config; /* Pointer to the configuration of the * L3GD20 sensor */ uint64_t timestamp; /* Units is microseconds */ struct sensor_lowerhalf_s lower; /* The struct of lower half driver */ #if CONFIG_SENSORS_L3GD20_BUFFER_SIZE > 0 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 */ #endif }; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ #ifdef CONFIG_DEBUG_SENSORS_INFO static void l3gd20_read_register(FAR struct l3gd20_dev_s *dev, uint8_t const reg_addr, uint8_t *reg_data); #endif static void l3gd20_write_register(FAR struct l3gd20_dev_s *dev, uint8_t const reg_addr, uint8_t const reg_data); static void l3gd20_reset(FAR struct l3gd20_dev_s *dev); static void l3gd20_read_measurement_data(FAR struct l3gd20_dev_s *dev, FAR struct sensor_event_gyro *data); static void l3gd20_read_gyroscope_data(FAR struct l3gd20_dev_s *dev, uint16_t *x_gyr, uint16_t *y_gyr, uint16_t *z_gyr); static void l3gd20_read_temperature(FAR struct l3gd20_dev_s *dev, uint8_t * temperature); static int l3gd20_interrupt_handler(int irq, FAR void *context, FAR void *arg); static int l3gd20_activate(FAR struct sensor_lowerhalf_s *lower, bool enable); #if CONFIG_SENSORS_L3GD20_BUFFER_SIZE > 0 static void l3gd20_worker(FAR void *arg); #else static int l3gd20_fetch(FAR struct sensor_lowerhalf_s *lower, FAR char *buffer, size_t buflen); #endif /**************************************************************************** * Private Data ****************************************************************************/ /* The lower half sensor driver operations for sensor register */ static const struct sensor_ops_s g_l2gd20_ops = { .activate = l3gd20_activate, .set_interval = NULL, .batch = NULL, #if CONFIG_SENSORS_L3GD20_BUFFER_SIZE > 0 .fetch = NULL, #else .fetch = l3gd20_fetch, #endif .control = NULL }; /* Single linked list to store instances of drivers */ static struct l3gd20_dev_s *g_l3gd20_list = NULL; /**************************************************************************** * Private Functions ****************************************************************************/ #ifdef CONFIG_DEBUG_SENSORS_INFO /**************************************************************************** * Name: l3gd20_read_register ****************************************************************************/ static void l3gd20_read_register(FAR struct l3gd20_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 L3GD20 */ 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 L3GD20 */ SPI_SELECT(dev->spi, dev->config->spi_devid, false); /* Unlock the SPI bus */ SPI_LOCK(dev->spi, false); } #endif /**************************************************************************** * Name: l3gd20_write_register ****************************************************************************/ static void l3gd20_write_register(FAR struct l3gd20_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 L3GD20 */ 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 L3GD20 */ SPI_SELECT(dev->spi, dev->config->spi_devid, false); /* Unlock the SPI bus */ SPI_LOCK(dev->spi, false); } /**************************************************************************** * Name: l3gd20_reset ****************************************************************************/ static void l3gd20_reset(FAR struct l3gd20_dev_s *dev) { /* Reboot memory content */ l3gd20_write_register(dev, L3GD20_CTRL_REG_5, L3GD20_CTRL_REG_5_BOOT_BM); up_mdelay(100); } /**************************************************************************** * Name: l3gd20_read_measurement_data ****************************************************************************/ static void l3gd20_read_measurement_data(FAR struct l3gd20_dev_s *dev, FAR struct sensor_event_gyro *data) { uint16_t x_gyr = 0; uint16_t y_gyr = 0; uint16_t z_gyr = 0; uint8_t temperature = 0; /* Read Gyroscope */ l3gd20_read_gyroscope_data(dev, &x_gyr, &y_gyr, &z_gyr); /* Read Temperature */ l3gd20_read_temperature(dev, &temperature); data->x = ((int16_t)x_gyr / 180.0f) * (float)M_PI; data->y = ((int16_t)y_gyr / 180.0f) * (float)M_PI; data->z = ((int16_t)z_gyr / 180.0f) * (float)M_PI; data->temperature = temperature; data->timestamp = dev->timestamp; /* Feed sensor data to entropy pool */ add_sensor_randomness((x_gyr << 16) ^ (y_gyr << 8) ^ (z_gyr << 0)); } /**************************************************************************** * Name: l3gd20_read_gyroscope_data ****************************************************************************/ static void l3gd20_read_gyroscope_data(FAR struct l3gd20_dev_s *dev, uint16_t * x_gyr, uint16_t * y_gyr, uint16_t * z_gyr) { /* 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 L3GD20 */ 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 * 0x40 -> MSB-1 (MS-Bit) is set -> auto increment of address when reading * multiple bytes. */ SPI_SEND(dev->spi, (L3GD20_OUT_X_L_REG | 0x80 | 0x40)); /* RX */ *x_gyr = ((uint16_t) (SPI_SEND(dev->spi, 0)) << 0); /* LSB */ *x_gyr |= ((uint16_t) (SPI_SEND(dev->spi, 0)) << 8); /* MSB */ *y_gyr = ((uint16_t) (SPI_SEND(dev->spi, 0)) << 0); /* LSB */ *y_gyr |= ((uint16_t) (SPI_SEND(dev->spi, 0)) << 8); /* MSB */ *z_gyr = ((uint16_t) (SPI_SEND(dev->spi, 0)) << 0); /* LSB */ *z_gyr |= ((uint16_t) (SPI_SEND(dev->spi, 0)) << 8); /* MSB */ /* Set CS to high which deselects the L3GD20 */ SPI_SELECT(dev->spi, dev->config->spi_devid, false); /* Unlock the SPI bus */ SPI_LOCK(dev->spi, false); } /**************************************************************************** * Name: l3gd20_read_temperature ****************************************************************************/ static void l3gd20_read_temperature(FAR struct l3gd20_dev_s *dev, FAR uint8_t *temperature) { /* 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 L3GD20 */ 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, (L3GD20_OUT_TEMP_REG | 0x80)); /* RX */ *temperature = (SPI_SEND(dev->spi, 0)); /* Set CS to high which deselects the L3GD20 */ SPI_SELECT(dev->spi, dev->config->spi_devid, false); /* Unlock the SPI bus */ SPI_LOCK(dev->spi, false); } /**************************************************************************** * Name: l3gd20_interrupt_handler ****************************************************************************/ static int l3gd20_interrupt_handler(int irq, FAR void *context, FAR void *arg) { /* This function should be called upon a rising edge on the L3GD20 new data * interrupt pin since it signals that new data has been measured. */ FAR struct l3gd20_dev_s *priv = 0; int ret; /* Find out which L3GD20 device caused the interrupt */ for (priv = g_l3gd20_list; priv && priv->config->irq != irq; priv = priv->flink) { DEBUGASSERT(priv != NULL); } /* Get the timestamp */ priv->timestamp = sensor_get_timestamp(); #if CONFIG_SENSORS_L3GD20_BUFFER_SIZE > 0 /* 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. */ DEBUGASSERT(priv->work.worker == NULL); ret = work_queue(HPWORK, &priv->work, l3gd20_worker, priv, 0); if (ret < 0) { snerr("ERROR: Failed to queue work: %d\n", ret); return ret; } #else /* notify event to upper half driver */ priv->lower.notify_event(priv->lower.priv); #endif return OK; } #if CONFIG_SENSORS_L3GD20_BUFFER_SIZE > 0 /**************************************************************************** * Name: l3gd20_worker ****************************************************************************/ static void l3gd20_worker(FAR void *arg) { struct sensor_event_gyro temp; FAR struct l3gd20_dev_s *priv = (FAR struct l3gd20_dev_s *)(arg); DEBUGASSERT(priv != NULL); /* Read out the latest sensor data */ l3gd20_read_measurement_data(priv, &temp); /* push data to upper half driver */ priv->lower.push_event(priv->lower.priv, &temp, sizeof(struct sensor_event_gyro)); } #else /**************************************************************************** * Name: l3gd20_fetch ****************************************************************************/ static int l3gd20_fetch(FAR struct sensor_lowerhalf_s *lower, FAR char *buffer, size_t buflen) { FAR struct l3gd20_dev_s *priv = container_of(lower, FAR struct l3gd20_dev_s, lower); if (buflen != sizeof(struct sensor_event_gyro)) return 0; DEBUGASSERT(priv != NULL); /* Read out the latest sensor data */ l3gd20_read_measurement_data(priv, (FAR struct sensor_event_gyro *)buffer); return sizeof(struct sensor_event_gyro); } #endif /**************************************************************************** * Name: l3gd20_activate ****************************************************************************/ static int l3gd20_activate(FAR struct sensor_lowerhalf_s *lower, bool enable) { FAR struct l3gd20_dev_s *priv = container_of(lower, FAR struct l3gd20_dev_s, lower); struct sensor_event_gyro temp; #ifdef CONFIG_DEBUG_SENSORS_INFO uint8_t reg_content; uint8_t reg_addr; #endif DEBUGASSERT(priv != NULL); if (enable == true) { /* Perform a reset */ l3gd20_reset(priv); /* Enable DRDY signal on INT 2 */ l3gd20_write_register(priv, L3GD20_CTRL_REG_3, L3GD20_CTRL_REG_3_I2_DRDY_BM); /* Enable the maximum full scale mode. * Enable block data update for gyro sensor data. * This should prevent race conditions when reading sensor data. */ l3gd20_write_register(priv, L3GD20_CTRL_REG_4, L3GD20_CTRL_REG_4_BDU_BM | L3GD20_CTRL_REG_4_FS_1_BM | L3GD20_CTRL_REG_4_FS_0_BM); /* Enable X,Y,Z axis * DR=00 -> Output data rate = 95 Hz, Cut-off = 12.5 */ l3gd20_write_register(priv, L3GD20_CTRL_REG_1, L3GD20_CTRL_REG_1_POWERDOWN_BM | L3GD20_CTRL_REG_1_X_EN_BM | L3GD20_CTRL_REG_1_Y_EN_BM | L3GD20_CTRL_REG_1_Z_EN_BM); /* Read measurement data to ensure DRDY is low */ l3gd20_read_measurement_data(priv, &temp); /* Read back the content of all control registers for debug purposes */ #ifdef CONFIG_DEBUG_SENSORS_INFO reg_content = 0; l3gd20_read_register(priv, L3GD20_WHO_AM_I, ®_content); sninfo("WHO_AM_I_REG = %04x\n", reg_content); for (reg_addr = L3GD20_CTRL_REG_1; reg_addr <= L3GD20_CTRL_REG_5; reg_addr++) { l3gd20_read_register(priv, reg_addr, ®_content); sninfo("R#%04x = %04x\n", reg_addr, reg_content); } l3gd20_read_register(priv, L3GD20_STATUS_REG, ®_content); sninfo("STATUS_REG = %04x\n", reg_content); #endif } else { /* Perform a reset */ l3gd20_reset(priv); } return 0; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: l3gd20_register * * Description: * Register the L3DF20 character device as 'devpath'. * * Input Parameters: * devno - The device number, used to build the device path * as /dev/sensor/gyro_uncalN * spi - An SPI driver instance. * config - configuration for the L3GD20 driver. * * Returned Value: * Zero (OK) on success; a negated errno value on failure. * ****************************************************************************/ int l3gd20_register(int devno, FAR struct spi_dev_s *spi, FAR struct l3gd20_config_s *config) { FAR struct l3gd20_dev_s *priv; int ret = OK; /* Sanity check */ DEBUGASSERT(spi != NULL); DEBUGASSERT(config != NULL); /* Initialize the L3GD20 device structure */ priv = (FAR struct l3gd20_dev_s *)kmm_malloc(sizeof(struct l3gd20_dev_s)); if (priv == NULL) { snerr("ERROR: Failed to allocate instance\n"); ret = -ENOMEM; goto errout; } priv->spi = spi; priv->config = config; #if CONFIG_SENSORS_L3GD20_BUFFER_SIZE > 0 priv->work.worker = NULL; #endif priv->timestamp = 0; priv->lower.type = SENSOR_TYPE_GYROSCOPE; priv->lower.buffer_number = CONFIG_SENSORS_L3GD20_BUFFER_SIZE; priv->lower.ops = &g_l2gd20_ops; priv->lower.uncalibrated = true; /* Setup SPI frequency and mode */ SPI_SETFREQUENCY(spi, L3GD20_SPI_FREQUENCY); SPI_SETMODE(spi, L3GD20_SPI_MODE); /* Attach the interrupt handler */ ret = priv->config->attach(priv->config, &l3gd20_interrupt_handler); if (ret < 0) { snerr("ERROR: Failed to attach interrupt\n"); goto errout; } /* Register the sensor driver */ ret = sensor_register(&priv->lower, devno); if (ret < 0) { snerr("ERROR: Failed to register driver: %d\n", ret); kmm_free(priv); goto errout; } /* Since we support multiple L3GD20 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_l3gd20_list; g_l3gd20_list = priv; errout: return ret; } #endif /* CONFIG_SPI && CONFIG_SENSORS_L3GD20 */