/**************************************************************************** * drivers/sensors/bh1750fvi.c * Character driver for the Rohm Ambient Light Sensor BH1750FVI * * Copyright (C) 2015-2016 Gregory Nutt. All rights reserved. * Author: Gregory Nutt * * Copyright (C) 2016 Alan Carvalho de Assis. All rights reserved. * Author: Alan Carvalho de Assis * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #include #include #include #include #include #include #include #include #if defined(CONFIG_I2C) && defined(CONFIG_BH1750FVI) /**************************************************************************** * Pre-process Definitions ****************************************************************************/ #ifndef CONFIG_BH1750FVI_I2C_FREQUENCY # define CONFIG_BH1750FVI_I2C_FREQUENCY 400000 #endif /**************************************************************************** * Private Types ****************************************************************************/ struct bh1750fvi_dev_s { FAR struct i2c_master_s *i2c; /* I2C interface */ uint8_t addr; /* I2C address */ }; /**************************************************************************** * Private Function Prototypes ****************************************************************************/ /* I2C Helpers */ static int bh1750fvi_read16(FAR struct bh1750fvi_dev_s *priv, FAR uint16_t *regval); static int bh1750fvi_write8(FAR struct bh1750fvi_dev_s *priv, uint8_t regval); /* Character driver methods */ static int bh1750fvi_open(FAR struct file *filep); static int bh1750fvi_close(FAR struct file *filep); static ssize_t bh1750fvi_read(FAR struct file *filep, FAR char *buffer, size_t buflen); static ssize_t bh1750fvi_write(FAR struct file *filep, FAR const char *buffer, size_t buflen); static int bh1750fvi_ioctl(FAR struct file *filep, int cmd, unsigned long arg); /**************************************************************************** * Private Data ****************************************************************************/ static const struct file_operations g_bh1750fvi_fops = { bh1750fvi_open, /* open */ bh1750fvi_close, /* close */ bh1750fvi_read, /* read */ bh1750fvi_write, /* write */ NULL, /* seek */ bh1750fvi_ioctl /* ioctl */ #ifndef CONFIG_DISABLE_POLL , NULL /* poll */ #endif #ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS , NULL /* unlink */ #endif }; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: bh1750fvi_read16 * * Description: * Read 16-bit register * ****************************************************************************/ static int bh1750fvi_read16(FAR struct bh1750fvi_dev_s *priv, FAR uint16_t *regval) { struct i2c_config_s config; uint8_t buffer[2]; int ret = -1; /* Set up the I2C configuration */ config.frequency = CONFIG_BH1750FVI_I2C_FREQUENCY; config.address = priv->addr; config.addrlen = 7; /* Read 16-bits from the device */ ret = i2c_read(priv->i2c, &config, buffer, 2); if (ret < 0) { snerr ("i2c_read failed: %d\n", ret); return ret; } /* Copy the content of the buffer to the location of the uint16_t pointer */ *regval = (uint16_t)((buffer[0]<<8) | (buffer[1])); sninfo("value: %08x ret: %d\n", *regval, ret); return OK; } /**************************************************************************** * Name: bh1750fvi_write8 * * Description: * Write from an 8-bit register * ****************************************************************************/ static int bh1750fvi_write8(FAR struct bh1750fvi_dev_s *priv, uint8_t regval) { struct i2c_config_s config; int ret; sninfo("value: %02x\n", regval); /* Set up the I2C configuration */ config.frequency = CONFIG_BH1750FVI_I2C_FREQUENCY; config.address = priv->addr; config.addrlen = 7; /* Write 8 bits to device */ ret = i2c_write(priv->i2c, &config, ®val, 1); if (ret < 0) { snerr("ERROR: i2c_write failed: %d\n", ret); } return ret; } /**************************************************************************** * Name: bh1750fvi_open * * Description: * This function is called whenever the BH1750FVI device is opened. * ****************************************************************************/ static int bh1750fvi_open(FAR struct file *filep) { return OK; } /**************************************************************************** * Name: bh1750fvi_close * * Description: * This routine is called when the BH1750FVI device is closed. * ****************************************************************************/ static int bh1750fvi_close(FAR struct file *filep) { return OK; } /**************************************************************************** * Name: bh1750fvi_read ****************************************************************************/ static ssize_t bh1750fvi_read(FAR struct file *filep, FAR char *buffer, size_t buflen) { int ret; FAR struct inode *inode; FAR struct bh1750fvi_dev_s *priv; uint16_t lux = 0; DEBUGASSERT(filep); inode = filep->f_inode; DEBUGASSERT(inode && inode->i_private); priv = (FAR struct bh1750fvi_dev_s *)inode->i_private; /* Check if the user is reading the right size */ if (buflen != 2) { snerr("ERROR: You need to read 2 bytes from this sensor!\n"); return -EINVAL; } ret = bh1750fvi_read16(priv, &lux); if (ret < 0) { snerr("ERROR: Error reading light sensor!\n"); return ret; } buffer[0] = lux & 0xFF; buffer[1] = (lux & 0xFF00) >> 8; add_sensor_randomness(lux); return buflen; } /**************************************************************************** * Name: bh1750fvi_write ****************************************************************************/ static ssize_t bh1750fvi_write(FAR struct file *filep, FAR const char *buffer, size_t buflen) { return -ENOSYS; } /**************************************************************************** * Name: bh1750fvi_ioctl ****************************************************************************/ static int bh1750fvi_ioctl(FAR struct file *filep, int cmd, unsigned long arg) { FAR struct inode *inode = filep->f_inode; FAR struct bh1750fvi_dev_s *priv = inode->i_private; int ret = OK; switch (cmd) { /* Set device to Continuously H-Resolution Mode */ case SNIOC_CHRM: { ret = bh1750fvi_write8(priv, BH1750FVI_CONTINUOUS_HRM); if (ret < 0) { snerr("ERROR: Cannot change to Continuously H-Resolution Mode!\n"); } } break; /* Set device to Continuously H-Resolution Mode2 */ case SNIOC_CHRM2: { ret = bh1750fvi_write8(priv, BH1750FVI_CONTINUOUS_HRM2); if (ret < 0) { snerr("ERROR: Cannot change to Continuously H-Resolution Mode2!\n"); } } break; /* Set device to Continuously L-Resolution Mode */ case SNIOC_CLRM: { ret = bh1750fvi_write8(priv, BH1750FVI_CONTINUOUS_LRM); if (ret < 0) { snerr("ERROR: Cannot change to Continuously L-Resolution Mode!\n"); } } break; /* Set device to One Time H-Resolution Mode */ case SNIOC_OTHRM: { ret = bh1750fvi_write8(priv, BH1750FVI_ONETIME_HRM); if (ret < 0) { snerr("ERROR: Cannot change to One Time H-Resolution Mode!\n"); } } break; /* Set device to One Time H-Resolution Mode 2 */ case SNIOC_OTHRM2: { ret = bh1750fvi_write8(priv, BH1750FVI_ONETIME_HRM2); if (ret < 0) { snerr("ERROR: Cannot change to One Time H-Resolution Mode2!\n"); } } break; /* Set device to One Time L-Resolution Mode */ case SNIOC_OTLRM: { ret = bh1750fvi_write8(priv, BH1750FVI_ONETIME_LRM); if (ret < 0) { snerr("ERROR: Cannot change to One Time L-Resolution Mode!\n"); } } break; /* Change the Measurement Time */ case SNIOC_CHMEATIME: { FAR uint8_t *ptr = (FAR uint8_t *)((uintptr_t)arg); uint8_t reg; DEBUGASSERT(ptr != NULL); reg = BH1750FVI_MEASURE_TIMEH | ((*ptr & 0xE0) >> 5); ret = bh1750fvi_write8(priv, reg); if (ret < 0) { snerr("ERROR: Cannot Change Measure Time at MEASURE_TIMEH!\n"); } reg = BH1750FVI_MEASURE_TIMEL | (*ptr & 0x1F); ret = bh1750fvi_write8(priv, reg); if (ret < 0) { snerr("ERROR: Cannot Change Measure Time at MEASURE_TIMEL!\n"); } } break; default: snerr("ERROR: Unrecognized cmd: %d\n", cmd); ret = -ENOTTY; break; } return ret; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: bh1750fvi_register * * Description: * Register the BH1750FVI character device as 'devpath' * * Input Parameters: * devpath - The full path to the driver to register. E.g., "/dev/light0" * i2c - An instance of the I2C interface to use to communicate with BH1750FVI * addr - The I2C address of the BH1750FVI. * * Returned Value: * Zero (OK) on success; a negated errno value on failure. * ****************************************************************************/ int bh1750fvi_register(FAR const char *devpath, FAR struct i2c_master_s *i2c, uint8_t addr) { int ret; /* Sanity check */ DEBUGASSERT(i2c != NULL); /* Initialize the BH1750FVI device structure */ FAR struct bh1750fvi_dev_s *priv = (FAR struct bh1750fvi_dev_s *)kmm_malloc(sizeof(struct bh1750fvi_dev_s)); if (priv == NULL) { snerr("ERROR: Failed to allocate instance\n"); return -ENOMEM; } priv->i2c = i2c; priv->addr = addr; /* Power on the device */ ret = bh1750fvi_write8(priv, BH1750FVI_POWERON); if (ret < 0) { snerr("ERROR: Failed to power-on the BH1750FVI!\n"); return ret; } /* Set Continuosly H-Resolution Mode */ ret = bh1750fvi_write8(priv, BH1750FVI_CONTINUOUS_HRM); if (ret < 0) { snerr("ERROR: Failed to enable the Continuosly H-Resolution Mode!\n"); return ret; } /* Register the character driver */ ret = register_driver(devpath, &g_bh1750fvi_fops, 0666, priv); if (ret < 0) { snerr("ERROR: Failed to register driver: %d\n", ret); kmm_free(priv); } return ret; } #endif /* CONFIG_I2C && CONFIG_BH1750FVI */