// SPDX-License-Identifier: GPL-2.0-only
/*
* zopt2201.c - Support for IDT ZOPT2201 ambient light and UV B sensor
*
* Copyright 2017 Peter Meerwald-Stadler <[email protected]>
*
* Datasheet: https://www.idt.com/document/dst/zopt2201-datasheet
* 7-bit I2C slave addresses 0x53 (default) or 0x52 (programmed)
*
* TODO: interrupt support, ALS/UVB raw mode
*/
#include <linux/module.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
#include <linux/err.h>
#include <linux/delay.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
#include <linux/unaligned.h>
#define ZOPT2201_DRV_NAME "zopt2201"
/* Registers */
#define ZOPT2201_MAIN_CTRL 0x00
#define ZOPT2201_LS_MEAS_RATE 0x04
#define ZOPT2201_LS_GAIN 0x05
#define ZOPT2201_PART_ID 0x06
#define ZOPT2201_MAIN_STATUS 0x07
#define ZOPT2201_ALS_DATA 0x0d /* LSB first, 13 to 20 bits */
#define ZOPT2201_UVB_DATA 0x10 /* LSB first, 13 to 20 bits */
#define ZOPT2201_UV_COMP_DATA 0x13 /* LSB first, 13 to 20 bits */
#define ZOPT2201_COMP_DATA 0x16 /* LSB first, 13 to 20 bits */
#define ZOPT2201_INT_CFG 0x19
#define ZOPT2201_INT_PST 0x1a
#define ZOPT2201_MAIN_CTRL_LS_MODE BIT(3) /* 0 .. ALS, 1 .. UV B */
#define ZOPT2201_MAIN_CTRL_LS_EN BIT(1)
/* Values for ZOPT2201_LS_MEAS_RATE resolution / bit width */
#define ZOPT2201_MEAS_RES_20BIT 0 /* takes 400 ms */
#define ZOPT2201_MEAS_RES_19BIT 1 /* takes 200 ms */
#define ZOPT2201_MEAS_RES_18BIT 2 /* takes 100 ms, default */
#define ZOPT2201_MEAS_RES_17BIT 3 /* takes 50 ms */
#define ZOPT2201_MEAS_RES_16BIT 4 /* takes 25 ms */
#define ZOPT2201_MEAS_RES_13BIT 5 /* takes 3.125 ms */
#define ZOPT2201_MEAS_RES_SHIFT 4
/* Values for ZOPT2201_LS_MEAS_RATE measurement rate */
#define ZOPT2201_MEAS_FREQ_25MS 0
#define ZOPT2201_MEAS_FREQ_50MS 1
#define ZOPT2201_MEAS_FREQ_100MS 2 /* default */
#define ZOPT2201_MEAS_FREQ_200MS 3
#define ZOPT2201_MEAS_FREQ_500MS 4
#define ZOPT2201_MEAS_FREQ_1000MS 5
#define ZOPT2201_MEAS_FREQ_2000MS 6
/* Values for ZOPT2201_LS_GAIN */
#define ZOPT2201_LS_GAIN_1 0
#define ZOPT2201_LS_GAIN_3 1
#define ZOPT2201_LS_GAIN_6 2
#define ZOPT2201_LS_GAIN_9 3
#define ZOPT2201_LS_GAIN_18 4
/* Values for ZOPT2201_MAIN_STATUS */
#define ZOPT2201_MAIN_STATUS_POWERON BIT(5)
#define ZOPT2201_MAIN_STATUS_INT BIT(4)
#define ZOPT2201_MAIN_STATUS_DRDY BIT(3)
#define ZOPT2201_PART_NUMBER 0xb2
struct zopt2201_data {
struct i2c_client *client;
struct mutex lock;
u8 gain;
u8 res;
u8 rate;
};
static const struct {
unsigned int gain; /* gain factor */
unsigned int scale; /* micro lux per count */
} zopt2201_gain_als[] = {
{ 1, 19200000 },
{ 3, 6400000 },
{ 6, 3200000 },
{ 9, 2133333 },
{ 18, 1066666 },
};
static const struct {
unsigned int gain; /* gain factor */
unsigned int scale; /* micro W/m2 per count */
} zopt2201_gain_uvb[] = {
{ 1, 460800 },
{ 3, 153600 },
{ 6, 76800 },
{ 9, 51200 },
{ 18, 25600 },
};
static const struct {
unsigned int bits; /* sensor resolution in bits */
unsigned long us; /* measurement time in micro seconds */
} zopt2201_resolution[] = {
{ 20, 400000 },
{ 19, 200000 },
{ 18, 100000 },
{ 17, 50000 },
{ 16, 25000 },
{ 13, 3125 },
};
static const struct {
unsigned int scale, uscale; /* scale factor as integer + micro */
u8 gain; /* gain register value */
u8 res; /* resolution register value */
} zopt2201_scale_als[] = {
{ 19, 200000, 0, 5 },
{ 6, 400000, 1, 5 },
{ 3, 200000, 2, 5 },
{ 2, 400000, 0, 4 },
{ 2, 133333, 3, 5 },
{ 1, 200000, 0, 3 },
{ 1, 66666, 4, 5 },
{ 0, 800000, 1, 4 },
{ 0, 600000, 0, 2 },
{ 0, 400000, 2, 4 },
{ 0, 300000, 0, 1 },
{ 0, 266666, 3, 4 },
{ 0, 200000, 2, 3 },
{ 0, 150000, 0, 0 },
{ 0, 133333, 4, 4 },
{ 0, 100000, 2, 2 },
{ 0, 66666, 4, 3 },
{ 0, 50000, 2, 1 },
{ 0, 33333, 4, 2 },
{ 0, 25000, 2, 0 },
{ 0, 16666, 4, 1 },
{ 0, 8333, 4, 0 },
};
static const struct {
unsigned int scale, uscale; /* scale factor as integer + micro */
u8 gain; /* gain register value */
u8 res; /* resolution register value */
} zopt2201_scale_uvb[] = {
{ 0, 460800, 0, 5 },
{ 0, 153600, 1, 5 },
{ 0, 76800, 2, 5 },
{ 0, 57600, 0, 4 },
{ 0, 51200, 3, 5 },
{ 0, 28800, 0, 3 },
{ 0, 25600, 4, 5 },
{ 0, 19200, 1, 4 },
{ 0, 14400, 0, 2 },
{ 0, 9600, 2, 4 },
{ 0, 7200, 0, 1 },
{ 0, 6400, 3, 4 },
{ 0, 4800, 2, 3 },
{ 0, 3600, 0, 0 },
{ 0, 3200, 4, 4 },
{ 0, 2400, 2, 2 },
{ 0, 1600, 4, 3 },
{ 0, 1200, 2, 1 },
{ 0, 800, 4, 2 },
{ 0, 600, 2, 0 },
{ 0, 400, 4, 1 },
{ 0, 200, 4, 0 },
};
static int zopt2201_enable_mode(struct zopt2201_data *data, bool uvb_mode)
{
u8 out = ZOPT2201_MAIN_CTRL_LS_EN;
if (uvb_mode)
out |= ZOPT2201_MAIN_CTRL_LS_MODE;
return i2c_smbus_write_byte_data(data->client, ZOPT2201_MAIN_CTRL, out);
}
static int zopt2201_read(struct zopt2201_data *data, u8 reg)
{
struct i2c_client *client = data->client;
int tries = 10;
u8 buf[3];
int ret;
mutex_lock(&data->lock);
ret = zopt2201_enable_mode(data, reg == ZOPT2201_UVB_DATA);
if (ret < 0)
goto fail;
while (tries--) {
unsigned long t = zopt2201_resolution[data->res].us;
if (t <= 20000)
usleep_range(t, t + 1000);
else
msleep(t / 1000);
ret = i2c_smbus_read_byte_data(client, ZOPT2201_MAIN_STATUS);
if (ret < 0)
goto fail;
if (ret & ZOPT2201_MAIN_STATUS_DRDY)
break;
}
if (tries < 0) {
ret = -ETIMEDOUT;
goto fail;
}
ret = i2c_smbus_read_i2c_block_data(client, reg, sizeof(buf), buf);
if (ret < 0)
goto fail;
ret = i2c_smbus_write_byte_data(client, ZOPT2201_MAIN_CTRL, 0x00);
if (ret < 0)
goto fail;
mutex_unlock(&data->lock);
return get_unaligned_le24(&buf[0]);
fail:
mutex_unlock(&data->lock);
return ret;
}
static const struct iio_chan_spec zopt2201_channels[] = {
{
.type = IIO_LIGHT,
.address = ZOPT2201_ALS_DATA,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
},
{
.type = IIO_INTENSITY,
.modified = 1,
.channel2 = IIO_MOD_LIGHT_UV,
.address = ZOPT2201_UVB_DATA,
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
BIT(IIO_CHAN_INFO_SCALE),
.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME),
},
{
.type = IIO_UVINDEX,
.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),
},
};
static int zopt2201_read_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int *val, int *val2, long mask)
{
struct zopt2201_data *data = iio_priv(indio_dev);
u64 tmp;
int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
ret = zopt2201_read(data, chan->address);
if (ret < 0)
return ret;
*val = ret;
return IIO_VAL_INT;
case IIO_CHAN_INFO_PROCESSED:
ret = zopt2201_read(data, ZOPT2201_UVB_DATA);
if (ret < 0)
return ret;
*val = ret * 18 *
(1 << (20 - zopt2201_resolution[data->res].bits)) /
zopt2201_gain_uvb[data->gain].gain;
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
switch (chan->address) {
case ZOPT2201_ALS_DATA:
*val = zopt2201_gain_als[data->gain].scale;
break;
case ZOPT2201_UVB_DATA:
*val = zopt2201_gain_uvb[data->gain].scale;
break;
default:
return -EINVAL;
}
*val2 = 1000000;
*val2 *= (1 << (zopt2201_resolution[data->res].bits - 13));
tmp = div_s64(*val * 1000000ULL, *val2);
*val = div_s64_rem(tmp, 1000000, val2);
return IIO_VAL_INT_PLUS_MICRO;
case IIO_CHAN_INFO_INT_TIME:
*val = 0;
*val2 = zopt2201_resolution[data->res].us;
return IIO_VAL_INT_PLUS_MICRO;
default:
return -EINVAL;
}
}
static int zopt2201_set_resolution(struct zopt2201_data *data, u8 res)
{
int ret;
ret = i2c_smbus_write_byte_data(data->client, ZOPT2201_LS_MEAS_RATE,
(res << ZOPT2201_MEAS_RES_SHIFT) |
data->rate);
if (ret < 0)
return ret;
data->res = res;
return 0;
}
static int zopt2201_write_resolution(struct zopt2201_data *data,
int val, int val2)
{
int i, ret;
if (val != 0)
return -EINVAL;
for (i = 0; i < ARRAY_SIZE(zopt2201_resolution); i++)
if (val2 == zopt2201_resolution[i].us) {
mutex_lock(&data->lock);
ret = zopt2201_set_resolution(data, i);
mutex_unlock(&data->lock);
return ret;
}
return -EINVAL;
}
static int zopt2201_set_gain(struct zopt2201_data *data, u8 gain)
{
int ret;
ret = i2c_smbus_write_byte_data(data->client, ZOPT2201_LS_GAIN, gain);
if (ret < 0)
return ret;
data->gain = gain;
return 0;
}
static int zopt2201_write_scale_als_by_idx(struct zopt2201_data *data, int idx)
{
int ret;
mutex_lock(&data->lock);
ret = zopt2201_set_resolution(data, zopt2201_scale_als[idx].res);
if (ret < 0)
goto unlock;
ret = zopt2201_set_gain(data, zopt2201_scale_als[idx].gain);
unlock:
mutex_unlock(&data->lock);
return ret;
}
static int zopt2201_write_scale_als(struct zopt2201_data *data,
int val, int val2)
{
int i;
for (i = 0; i < ARRAY_SIZE(zopt2201_scale_als); i++)
if (val == zopt2201_scale_als[i].scale &&
val2 == zopt2201_scale_als[i].uscale) {
return zopt2201_write_scale_als_by_idx(data, i);
}
return -EINVAL;
}
static int zopt2201_write_scale_uvb_by_idx(struct zopt2201_data *data, int idx)
{
int ret;
mutex_lock(&data->lock);
ret = zopt2201_set_resolution(data, zopt2201_scale_als[idx].res);
if (ret < 0)
goto unlock;
ret = zopt2201_set_gain(data, zopt2201_scale_als[idx].gain);
unlock:
mutex_unlock(&data->lock);
return ret;
}
static int zopt2201_write_scale_uvb(struct zopt2201_data *data,
int val, int val2)
{
int i;
for (i = 0; i < ARRAY_SIZE(zopt2201_scale_uvb); i++)
if (val == zopt2201_scale_uvb[i].scale &&
val2 == zopt2201_scale_uvb[i].uscale)
return zopt2201_write_scale_uvb_by_idx(data, i);
return -EINVAL;
}
static int zopt2201_write_raw(struct iio_dev *indio_dev,
struct iio_chan_spec const *chan,
int val, int val2, long mask)
{
struct zopt2201_data *data = iio_priv(indio_dev);
switch (mask) {
case IIO_CHAN_INFO_INT_TIME:
return zopt2201_write_resolution(data, val, val2);
case IIO_CHAN_INFO_SCALE:
switch (chan->address) {
case ZOPT2201_ALS_DATA:
return zopt2201_write_scale_als(data, val, val2);
case ZOPT2201_UVB_DATA:
return zopt2201_write_scale_uvb(data, val, val2);
default:
return -EINVAL;
}
}
return -EINVAL;
}
static ssize_t zopt2201_show_int_time_available(struct device *dev,
struct device_attribute *attr,
char *buf)
{
size_t len = 0;
int i;
for (i = 0; i < ARRAY_SIZE(zopt2201_resolution); i++)
len += scnprintf(buf + len, PAGE_SIZE - len, "0.%06lu ",
zopt2201_resolution[i].us);
buf[len - 1] = '\n';
return len;
}
static IIO_DEV_ATTR_INT_TIME_AVAIL(zopt2201_show_int_time_available);
static ssize_t zopt2201_show_als_scale_avail(struct device *dev,
struct device_attribute *attr,
char *buf)
{
ssize_t len = 0;
int i;
for (i = 0; i < ARRAY_SIZE(zopt2201_scale_als); i++)
len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%06u ",
zopt2201_scale_als[i].scale,
zopt2201_scale_als[i].uscale);
buf[len - 1] = '\n';
return len;
}
static ssize_t zopt2201_show_uvb_scale_avail(struct device *dev,
struct device_attribute *attr,
char *buf)
{
ssize_t len = 0;
int i;
for (i = 0; i < ARRAY_SIZE(zopt2201_scale_uvb); i++)
len += scnprintf(buf + len, PAGE_SIZE - len, "%d.%06u ",
zopt2201_scale_uvb[i].scale,
zopt2201_scale_uvb[i].uscale);
buf[len - 1] = '\n';
return len;
}
static IIO_DEVICE_ATTR(in_illuminance_scale_available, 0444,
zopt2201_show_als_scale_avail, NULL, 0);
static IIO_DEVICE_ATTR(in_intensity_uv_scale_available, 0444,
zopt2201_show_uvb_scale_avail, NULL, 0);
static struct attribute *zopt2201_attributes[] = {
&iio_dev_attr_integration_time_available.dev_attr.attr,
&iio_dev_attr_in_illuminance_scale_available.dev_attr.attr,
&iio_dev_attr_in_intensity_uv_scale_available.dev_attr.attr,
NULL
};
static const struct attribute_group zopt2201_attribute_group = {
.attrs = zopt2201_attributes,
};
static const struct iio_info zopt2201_info = {
.read_raw = zopt2201_read_raw,
.write_raw = zopt2201_write_raw,
.attrs = &zopt2201_attribute_group,
};
static int zopt2201_probe(struct i2c_client *client)
{
struct zopt2201_data *data;
struct iio_dev *indio_dev;
int ret;
if (!i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_READ_I2C_BLOCK))
return -EOPNOTSUPP;
ret = i2c_smbus_read_byte_data(client, ZOPT2201_PART_ID);
if (ret < 0)
return ret;
if (ret != ZOPT2201_PART_NUMBER)
return -ENODEV;
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;
mutex_init(&data->lock);
indio_dev->info = &zopt2201_info;
indio_dev->channels = zopt2201_channels;
indio_dev->num_channels = ARRAY_SIZE(zopt2201_channels);
indio_dev->name = ZOPT2201_DRV_NAME;
indio_dev->modes = INDIO_DIRECT_MODE;
data->rate = ZOPT2201_MEAS_FREQ_100MS;
ret = zopt2201_set_resolution(data, ZOPT2201_MEAS_RES_18BIT);
if (ret < 0)
return ret;
ret = zopt2201_set_gain(data, ZOPT2201_LS_GAIN_3);
if (ret < 0)
return ret;
return devm_iio_device_register(&client->dev, indio_dev);
}
static const struct i2c_device_id zopt2201_id[] = {
{ "zopt2201" },
{ }
};
MODULE_DEVICE_TABLE(i2c, zopt2201_id);
static struct i2c_driver zopt2201_driver = {
.driver = {
.name = ZOPT2201_DRV_NAME,
},
.probe = zopt2201_probe,
.id_table = zopt2201_id,
};
module_i2c_driver(zopt2201_driver);
MODULE_AUTHOR("Peter Meerwald-Stadler <[email protected]>");
MODULE_DESCRIPTION("IDT ZOPT2201 ambient light and UV B sensor driver");
MODULE_LICENSE("GPL");
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