416 lines
11 KiB
C
416 lines
11 KiB
C
/****************************************************************************
|
|
* drivers/sensors/bh1750fvi.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.
|
|
*
|
|
****************************************************************************/
|
|
|
|
/* Character driver for the Rohm Ambient Light Sensor BH1750FVI */
|
|
|
|
/****************************************************************************
|
|
* Included Files
|
|
****************************************************************************/
|
|
|
|
#include <nuttx/config.h>
|
|
|
|
#include <assert.h>
|
|
#include <errno.h>
|
|
#include <debug.h>
|
|
#include <stdlib.h>
|
|
|
|
#include <nuttx/kmalloc.h>
|
|
#include <nuttx/fs/fs.h>
|
|
#include <nuttx/i2c/i2c_master.h>
|
|
#include <nuttx/sensors/bh1750fvi.h>
|
|
#include <nuttx/random.h>
|
|
|
|
#if defined(CONFIG_I2C) && defined(CONFIG_SENSORS_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 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 =
|
|
{
|
|
NULL, /* open */
|
|
NULL, /* close */
|
|
bh1750fvi_read, /* read */
|
|
bh1750fvi_write, /* write */
|
|
NULL, /* seek */
|
|
bh1750fvi_ioctl, /* ioctl */
|
|
};
|
|
|
|
/****************************************************************************
|
|
* 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_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;
|
|
|
|
inode = filep->f_inode;
|
|
|
|
DEBUGASSERT(inode->i_private);
|
|
priv = 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:");
|
|
snerr(" 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:");
|
|
snerr(" 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:");
|
|
snerr(" 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:");
|
|
snerr(" 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)
|
|
{
|
|
FAR struct bh1750fvi_dev_s *priv;
|
|
int ret;
|
|
|
|
/* Sanity check */
|
|
|
|
DEBUGASSERT(i2c != NULL);
|
|
|
|
/* Initialize the BH1750FVI device structure */
|
|
|
|
priv = 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 Continuously H-Resolution Mode */
|
|
|
|
ret = bh1750fvi_write8(priv, BH1750FVI_CONTINUOUS_HRM);
|
|
if (ret < 0)
|
|
{
|
|
snerr("ERROR: Failed to enable the Continuously 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_SENSORS_BH1750FVI */
|