linux/drivers/iio/light/vcnl4000.c

199 lines
5.0 KiB
C

/*
* vcnl4000.c - Support for Vishay VCNL4000 combined ambient light and
* proximity sensor
*
* Copyright 2012 Peter Meerwald <pmeerw@pmeerw.net>
*
* This file is subject to the terms and conditions of version 2 of
* the GNU General Public License. See the file COPYING in the main
* directory of this archive for more details.
*
* IIO driver for VCNL4000 (7-bit I2C slave address 0x13)
*
* TODO:
* allow to adjust IR current
* proximity threshold and event handling
*/
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#define VCNL4000_DRV_NAME "vcnl4000"
#define VCNL4000_COMMAND 0x80 /* Command register */
#define VCNL4000_PROD_REV 0x81 /* Product ID and Revision ID */
#define VCNL4000_LED_CURRENT 0x83 /* IR LED current for proximity mode */
#define VCNL4000_AL_PARAM 0x84 /* Ambient light parameter register */
#define VCNL4000_AL_RESULT_HI 0x85 /* Ambient light result register, MSB */
#define VCNL4000_AL_RESULT_LO 0x86 /* Ambient light result register, LSB */
#define VCNL4000_PS_RESULT_HI 0x87 /* Proximity result register, MSB */
#define VCNL4000_PS_RESULT_LO 0x88 /* Proximity result register, LSB */
#define VCNL4000_PS_MEAS_FREQ 0x89 /* Proximity test signal frequency */
#define VCNL4000_PS_MOD_ADJ 0x8a /* Proximity modulator timing adjustment */
/* Bit masks for COMMAND register */
#define VCNL4000_AL_RDY 0x40 /* ALS data ready? */
#define VCNL4000_PS_RDY 0x20 /* proximity data ready? */
#define VCNL4000_AL_OD 0x10 /* start on-demand ALS measurement */
#define VCNL4000_PS_OD 0x08 /* start on-demand proximity measurement */
struct vcnl4000_data {
struct i2c_client *client;
};
static const struct i2c_device_id vcnl4000_id[] = {
{ "vcnl4000", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, vcnl4000_id);
static int vcnl4000_measure(struct vcnl4000_data *data, u8 req_mask,
u8 rdy_mask, u8 data_reg, int *val)
{
int tries = 20;
__be16 buf;
int ret;
ret = i2c_smbus_write_byte_data(data->client, VCNL4000_COMMAND,
req_mask);
if (ret < 0)
return ret;
/* wait for data to become ready */
while (tries--) {
ret = i2c_smbus_read_byte_data(data->client, VCNL4000_COMMAND);
if (ret < 0)
return ret;
if (ret & rdy_mask)
break;
msleep(20); /* measurement takes up to 100 ms */
}
if (tries < 0) {
dev_err(&data->client->dev,
"vcnl4000_measure() failed, data not ready\n");
return -EIO;
}
ret = i2c_smbus_read_i2c_block_data(data->client,
data_reg, sizeof(buf), (u8 *) &buf);
if (ret < 0)
return ret;
*val = be16_to_cpu(buf);
return 0;
}
static const struct iio_chan_spec vcnl4000_channels[] = {
{
.type = IIO_LIGHT,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
}, {
.type = IIO_PROXIMITY,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
}
};
static int vcnl4000_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
int ret = -EINVAL;
struct vcnl4000_data *data = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_RAW:
switch (chan->type) {
case IIO_LIGHT:
ret = vcnl4000_measure(data,
VCNL4000_AL_OD, VCNL4000_AL_RDY,
VCNL4000_AL_RESULT_HI, val);
if (ret < 0)
return ret;
ret = IIO_VAL_INT;
break;
case IIO_PROXIMITY:
ret = vcnl4000_measure(data,
VCNL4000_PS_OD, VCNL4000_PS_RDY,
VCNL4000_PS_RESULT_HI, val);
if (ret < 0)
return ret;
ret = IIO_VAL_INT;
break;
default:
break;
}
break;
case IIO_CHAN_INFO_SCALE:
if (chan->type == IIO_LIGHT) {
*val = 0;
*val2 = 250000;
ret = IIO_VAL_INT_PLUS_MICRO;
}
break;
default:
break;
}
return ret;
}
static const struct iio_info vcnl4000_info = {
.read_raw = vcnl4000_read_raw,
.driver_module = THIS_MODULE,
};
static int vcnl4000_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct vcnl4000_data *data;
struct iio_dev *indio_dev;
int ret;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
if (!indio_dev)
return -ENOMEM;
data = iio_priv(indio_dev);
i2c_set_clientdata(client, indio_dev);
data->client = client;
ret = i2c_smbus_read_byte_data(data->client, VCNL4000_PROD_REV);
if (ret < 0)
return ret;
dev_info(&client->dev, "VCNL4000 Ambient light/proximity sensor, Prod %02x, Rev: %02x\n",
ret >> 4, ret & 0xf);
indio_dev->dev.parent = &client->dev;
indio_dev->info = &vcnl4000_info;
indio_dev->channels = vcnl4000_channels;
indio_dev->num_channels = ARRAY_SIZE(vcnl4000_channels);
indio_dev->name = VCNL4000_DRV_NAME;
indio_dev->modes = INDIO_DIRECT_MODE;
return devm_iio_device_register(&client->dev, indio_dev);
}
static struct i2c_driver vcnl4000_driver = {
.driver = {
.name = VCNL4000_DRV_NAME,
.owner = THIS_MODULE,
},
.probe = vcnl4000_probe,
.id_table = vcnl4000_id,
};
module_i2c_driver(vcnl4000_driver);
MODULE_AUTHOR("Peter Meerwald <pmeerw@pmeerw.net>");
MODULE_DESCRIPTION("Vishay VCNL4000 proximity/ambient light sensor driver");
MODULE_LICENSE("GPL");