// SPDX-License-Identifier: GPL-2.0+
/*
* Support for ON Semiconductor NOA1305 ambient light sensor
*
* Copyright (C) 2016 Emcraft Systems
* Copyright (C) 2019 Collabora Ltd.
*/
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/module.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
#define NOA1305_REG_POWER_CONTROL 0x0
#define NOA1305_POWER_CONTROL_DOWN 0x00
#define NOA1305_POWER_CONTROL_ON 0x08
#define NOA1305_REG_RESET 0x1
#define NOA1305_RESET_RESET 0x10
#define NOA1305_REG_INTEGRATION_TIME 0x2
#define NOA1305_INTEGR_TIME_800MS 0x00
#define NOA1305_INTEGR_TIME_400MS 0x01
#define NOA1305_INTEGR_TIME_200MS 0x02
#define NOA1305_INTEGR_TIME_100MS 0x03
#define NOA1305_INTEGR_TIME_50MS 0x04
#define NOA1305_INTEGR_TIME_25MS 0x05
#define NOA1305_INTEGR_TIME_12_5MS 0x06
#define NOA1305_INTEGR_TIME_6_25MS 0x07
#define NOA1305_INTEGR_TIME_MASK 0x07
#define NOA1305_REG_INT_SELECT 0x3
#define NOA1305_INT_SEL_ACTIVE_HIGH 0x01
#define NOA1305_INT_SEL_ACTIVE_LOW 0x02
#define NOA1305_INT_SEL_INACTIVE 0x03
#define NOA1305_REG_INT_THRESH_LSB 0x4
#define NOA1305_REG_INT_THRESH_MSB 0x5
#define NOA1305_REG_ALS_DATA_LSB 0x6
#define NOA1305_REG_ALS_DATA_MSB 0x7
#define NOA1305_REG_DEVICE_ID_LSB 0x8
#define NOA1305_REG_DEVICE_ID_MSB 0x9
#define NOA1305_DEVICE_ID 0x0519
#define NOA1305_DRIVER_NAME "noa1305"
static int noa1305_scale_available[] = {
100, 8 * 77, /* 800 ms */
100, 4 * 77, /* 400 ms */
100, 2 * 77, /* 200 ms */
100, 1 * 77, /* 100 ms */
1000, 5 * 77, /* 50 ms */
10000, 25 * 77, /* 25 ms */
100000, 125 * 77, /* 12.5 ms */
1000000, 625 * 77, /* 6.25 ms */
};
static int noa1305_int_time_available[] = {
0, 800000, /* 800 ms */
0, 400000, /* 400 ms */
0, 200000, /* 200 ms */
0, 100000, /* 100 ms */
0, 50000, /* 50 ms */
0, 25000, /* 25 ms */
0, 12500, /* 12.5 ms */
0, 6250, /* 6.25 ms */
};
struct noa1305_priv {
struct i2c_client *client;
struct regmap *regmap;
};
static int noa1305_measure(struct noa1305_priv *priv, int *val)
{
__le16 data;
int ret;
ret = regmap_bulk_read(priv->regmap, NOA1305_REG_ALS_DATA_LSB, &data,
2);
if (ret < 0)
return ret;
*val = le16_to_cpu(data);
return IIO_VAL_INT;
}
static int noa1305_scale(struct noa1305_priv *priv, int *val, int *val2)
{
int data;
int ret;
ret = regmap_read(priv->regmap, NOA1305_REG_INTEGRATION_TIME, &data);
if (ret < 0)
return ret;
/*
* Lux = count / (<Integration Constant> * <Integration Time>)
*
* Integration Constant = 7.7
* Integration Time in Seconds
*/
data &= NOA1305_INTEGR_TIME_MASK;
*val = noa1305_scale_available[2 * data + 0];
*val2 = noa1305_scale_available[2 * data + 1];
return IIO_VAL_FRACTIONAL;
}
static int noa1305_int_time(struct noa1305_priv *priv, int *val, int *val2)
{
int data;
int ret;
ret = regmap_read(priv->regmap, NOA1305_REG_INTEGRATION_TIME, &data);
if (ret < 0)
return ret;
data &= NOA1305_INTEGR_TIME_MASK;
*val = noa1305_int_time_available[2 * data + 0];
*val2 = noa1305_int_time_available[2 * data + 1];
return IIO_VAL_INT_PLUS_MICRO;
}
static const struct iio_chan_spec noa1305_channels[] = {
{
.type = IIO_LIGHT,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
.info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SCALE),
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
.info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME),
}
};
static int noa1305_read_avail(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
const int **vals, int *type,
int *length, long mask)
{
if (chan->type != IIO_LIGHT)
return -EINVAL;
switch (mask) {
case IIO_CHAN_INFO_SCALE:
*vals = noa1305_scale_available;
*length = ARRAY_SIZE(noa1305_scale_available);
*type = IIO_VAL_FRACTIONAL;
return IIO_AVAIL_LIST;
case IIO_CHAN_INFO_INT_TIME:
*vals = noa1305_int_time_available;
*length = ARRAY_SIZE(noa1305_int_time_available);
*type = IIO_VAL_INT_PLUS_MICRO;
return IIO_AVAIL_LIST;
default:
return -EINVAL;
}
}
static int noa1305_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct noa1305_priv *priv = iio_priv(indio_dev);
if (chan->type != IIO_LIGHT)
return -EINVAL;
switch (mask) {
case IIO_CHAN_INFO_RAW:
return noa1305_measure(priv, val);
case IIO_CHAN_INFO_SCALE:
return noa1305_scale(priv, val, val2);
case IIO_CHAN_INFO_INT_TIME:
return noa1305_int_time(priv, val, val2);
default:
return -EINVAL;
}
}
static int noa1305_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct noa1305_priv *priv = iio_priv(indio_dev);
int i;
if (chan->type != IIO_LIGHT)
return -EINVAL;
if (mask != IIO_CHAN_INFO_INT_TIME)
return -EINVAL;
if (val) /* >= 1s integration time not supported */
return -EINVAL;
/* Look up integration time register settings and write it if found. */
for (i = 0; i < ARRAY_SIZE(noa1305_int_time_available) / 2; i++)
if (noa1305_int_time_available[2 * i + 1] == val2)
return regmap_write(priv->regmap, NOA1305_REG_INTEGRATION_TIME, i);
return -EINVAL;
}
static const struct iio_info noa1305_info = {
.read_avail = noa1305_read_avail,
.read_raw = noa1305_read_raw,
.write_raw = noa1305_write_raw,
};
static bool noa1305_writable_reg(struct device *dev, unsigned int reg)
{
switch (reg) {
case NOA1305_REG_POWER_CONTROL:
case NOA1305_REG_RESET:
case NOA1305_REG_INTEGRATION_TIME:
case NOA1305_REG_INT_SELECT:
case NOA1305_REG_INT_THRESH_LSB:
case NOA1305_REG_INT_THRESH_MSB:
return true;
default:
return false;
}
}
static const struct regmap_config noa1305_regmap_config = {
.name = NOA1305_DRIVER_NAME,
.reg_bits = 8,
.val_bits = 8,
.max_register = NOA1305_REG_DEVICE_ID_MSB,
.writeable_reg = noa1305_writable_reg,
};
static int noa1305_probe(struct i2c_client *client)
{
struct noa1305_priv *priv;
struct iio_dev *indio_dev;
struct regmap *regmap;
__le16 data;
unsigned int dev_id;
int ret;
indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*priv));
if (!indio_dev)
return -ENOMEM;
regmap = devm_regmap_init_i2c(client, &noa1305_regmap_config);
if (IS_ERR(regmap)) {
dev_err(&client->dev, "Regmap initialization failed.\n");
return PTR_ERR(regmap);
}
priv = iio_priv(indio_dev);
ret = devm_regulator_get_enable(&client->dev, "vin");
if (ret)
return dev_err_probe(&client->dev, ret,
"get regulator vin failed\n");
i2c_set_clientdata(client, indio_dev);
priv->client = client;
priv->regmap = regmap;
ret = regmap_bulk_read(regmap, NOA1305_REG_DEVICE_ID_LSB, &data, 2);
if (ret < 0) {
dev_err(&client->dev, "ID reading failed: %d\n", ret);
return ret;
}
dev_id = le16_to_cpu(data);
if (dev_id != NOA1305_DEVICE_ID) {
dev_err(&client->dev, "Unknown device ID: 0x%x\n", dev_id);
return -ENODEV;
}
ret = regmap_write(regmap, NOA1305_REG_POWER_CONTROL,
NOA1305_POWER_CONTROL_ON);
if (ret < 0) {
dev_err(&client->dev, "Enabling power control failed\n");
return ret;
}
ret = regmap_write(regmap, NOA1305_REG_RESET, NOA1305_RESET_RESET);
if (ret < 0) {
dev_err(&client->dev, "Device reset failed\n");
return ret;
}
ret = regmap_write(regmap, NOA1305_REG_INTEGRATION_TIME,
NOA1305_INTEGR_TIME_800MS);
if (ret < 0) {
dev_err(&client->dev, "Setting integration time failed\n");
return ret;
}
indio_dev->info = &noa1305_info;
indio_dev->channels = noa1305_channels;
indio_dev->num_channels = ARRAY_SIZE(noa1305_channels);
indio_dev->name = NOA1305_DRIVER_NAME;
indio_dev->modes = INDIO_DIRECT_MODE;
ret = devm_iio_device_register(&client->dev, indio_dev);
if (ret)
dev_err(&client->dev, "registering device failed\n");
return ret;
}
static const struct of_device_id noa1305_of_match[] = {
{ .compatible = "onnn,noa1305" },
{ }
};
MODULE_DEVICE_TABLE(of, noa1305_of_match);
static const struct i2c_device_id noa1305_ids[] = {
{ "noa1305" },
{ }
};
MODULE_DEVICE_TABLE(i2c, noa1305_ids);
static struct i2c_driver noa1305_driver = {
.driver = {
.name = NOA1305_DRIVER_NAME,
.of_match_table = noa1305_of_match,
},
.probe = noa1305_probe,
.id_table = noa1305_ids,
};
module_i2c_driver(noa1305_driver);
MODULE_AUTHOR("Sergei Miroshnichenko <[email protected]>");
MODULE_AUTHOR("Martyn Welch <[email protected]");
MODULE_DESCRIPTION("ON Semiconductor NOA1305 ambient light sensor");
MODULE_LICENSE("GPL");
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