mirror of
https://github.com/torvalds/linux.git
synced 2024-09-20 23:13:00 +00:00
iio: light: driver for Lite-On ltr390
Implements driver for the Ambient/UV Light sensor LTR390. The driver exposes two ways of getting sensor readings: 1. Raw UV Counts directly from the sensor 2. The computed UV Index value with a percision of 2 decimal places [NOTE] Ambient light sensing has not been implemented yet. Driver tested on RPi Zero 2W Datasheet: https://optoelectronics.liteon.com/upload/download/DS86-2015-0004/LTR-390UV_Final_%20DS_V1%201.pdf Signed-off-by: Anshul Dalal <anshulusr@gmail.com> Link: https://lore.kernel.org/r/20231208102211.413019-2-anshulusr@gmail.com Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
This commit is contained in:
parent
48ba7d2f24
commit
8b0d4c40d7
|
@ -12663,6 +12663,13 @@ S: Maintained
|
|||
W: http://linux-test-project.github.io/
|
||||
T: git https://github.com/linux-test-project/ltp.git
|
||||
|
||||
LTR390 AMBIENT/UV LIGHT SENSOR DRIVER
|
||||
M: Anshul Dalal <anshulusr@gmail.com>
|
||||
L: linux-iio@vger.kernel.org
|
||||
S: Maintained
|
||||
F: Documentation/devicetree/bindings/iio/light/liteon,ltr390.yaml
|
||||
F: drivers/iio/light/ltr390.c
|
||||
|
||||
LYNX 28G SERDES PHY DRIVER
|
||||
M: Ioana Ciornei <ioana.ciornei@nxp.com>
|
||||
L: netdev@vger.kernel.org
|
||||
|
|
|
@ -362,6 +362,17 @@ config SENSORS_LM3533
|
|||
changes. The ALS-control output values can be set per zone for the
|
||||
three current output channels.
|
||||
|
||||
config LTR390
|
||||
tristate "LTR-390UV-01 ambient light and UV sensor"
|
||||
depends on I2C
|
||||
select REGMAP_I2C
|
||||
help
|
||||
If you say yes here you get support for the Lite-On LTR-390UV-01
|
||||
ambient light and UV sensor.
|
||||
|
||||
This driver can also be built as a module. If so, the module
|
||||
will be called ltr390.
|
||||
|
||||
config LTR501
|
||||
tristate "LTR-501ALS-01 light sensor"
|
||||
depends on I2C
|
||||
|
|
|
@ -31,6 +31,7 @@ obj-$(CONFIG_ISL29125) += isl29125.o
|
|||
obj-$(CONFIG_ISL76682) += isl76682.o
|
||||
obj-$(CONFIG_JSA1212) += jsa1212.o
|
||||
obj-$(CONFIG_SENSORS_LM3533) += lm3533-als.o
|
||||
obj-$(CONFIG_LTR390) += ltr390.o
|
||||
obj-$(CONFIG_LTR501) += ltr501.o
|
||||
obj-$(CONFIG_LTRF216A) += ltrf216a.o
|
||||
obj-$(CONFIG_LV0104CS) += lv0104cs.o
|
||||
|
|
196
drivers/iio/light/ltr390.c
Normal file
196
drivers/iio/light/ltr390.c
Normal file
|
@ -0,0 +1,196 @@
|
|||
// SPDX-License-Identifier: GPL-2.0-or-later
|
||||
/*
|
||||
* IIO driver for Lite-On LTR390 ALS and UV sensor
|
||||
* (7-bit I2C slave address 0x53)
|
||||
*
|
||||
* Based on the work of:
|
||||
* Shreeya Patel and Shi Zhigang (LTRF216 Driver)
|
||||
*
|
||||
* Copyright (C) 2023 Anshul Dalal <anshulusr@gmail.com>
|
||||
*
|
||||
* Datasheet:
|
||||
* https://optoelectronics.liteon.com/upload/download/DS86-2015-0004/LTR-390UV_Final_%20DS_V1%201.pdf
|
||||
*
|
||||
* TODO:
|
||||
* - Support for configurable gain and resolution
|
||||
* - Sensor suspend/resume support
|
||||
* - Add support for reading the ALS
|
||||
* - Interrupt support
|
||||
*/
|
||||
|
||||
#include <linux/i2c.h>
|
||||
#include <linux/math.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/mutex.h>
|
||||
#include <linux/regmap.h>
|
||||
|
||||
#include <linux/iio/iio.h>
|
||||
|
||||
#include <asm/unaligned.h>
|
||||
|
||||
#define LTR390_MAIN_CTRL 0x00
|
||||
#define LTR390_PART_ID 0x06
|
||||
#define LTR390_UVS_DATA 0x10
|
||||
|
||||
#define LTR390_SW_RESET BIT(4)
|
||||
#define LTR390_UVS_MODE BIT(3)
|
||||
#define LTR390_SENSOR_ENABLE BIT(1)
|
||||
|
||||
#define LTR390_PART_NUMBER_ID 0xb
|
||||
|
||||
/*
|
||||
* At 20-bit resolution (integration time: 400ms) and 18x gain, 2300 counts of
|
||||
* the sensor are equal to 1 UV Index [Datasheet Page#8].
|
||||
*
|
||||
* For the default resolution of 18-bit (integration time: 100ms) and default
|
||||
* gain of 3x, the counts/uvi are calculated as follows:
|
||||
* 2300 / ((3/18) * (100/400)) = 95.83
|
||||
*/
|
||||
#define LTR390_COUNTS_PER_UVI 96
|
||||
|
||||
/*
|
||||
* Window Factor is needed when the device is under Window glass with coated
|
||||
* tinted ink. This is to compensate for the light loss due to the lower
|
||||
* transmission rate of the window glass and helps * in calculating lux.
|
||||
*/
|
||||
#define LTR390_WINDOW_FACTOR 1
|
||||
|
||||
struct ltr390_data {
|
||||
struct regmap *regmap;
|
||||
struct i2c_client *client;
|
||||
/* Protects device from simulataneous reads */
|
||||
struct mutex lock;
|
||||
};
|
||||
|
||||
static const struct regmap_config ltr390_regmap_config = {
|
||||
.name = "ltr390",
|
||||
.reg_bits = 8,
|
||||
.reg_stride = 1,
|
||||
.val_bits = 8,
|
||||
};
|
||||
|
||||
static int ltr390_register_read(struct ltr390_data *data, u8 register_address)
|
||||
{
|
||||
struct device *dev = &data->client->dev;
|
||||
int ret;
|
||||
u8 recieve_buffer[3];
|
||||
|
||||
guard(mutex)(&data->lock);
|
||||
|
||||
ret = regmap_bulk_read(data->regmap, register_address, recieve_buffer,
|
||||
sizeof(recieve_buffer));
|
||||
if (ret) {
|
||||
dev_err(dev, "failed to read measurement data");
|
||||
return ret;
|
||||
}
|
||||
|
||||
return get_unaligned_le24(recieve_buffer);
|
||||
}
|
||||
|
||||
static int ltr390_read_raw(struct iio_dev *iio_device,
|
||||
struct iio_chan_spec const *chan, int *val,
|
||||
int *val2, long mask)
|
||||
{
|
||||
int ret;
|
||||
struct ltr390_data *data = iio_priv(iio_device);
|
||||
|
||||
switch (mask) {
|
||||
case IIO_CHAN_INFO_RAW:
|
||||
ret = ltr390_register_read(data, LTR390_UVS_DATA);
|
||||
if (ret < 0)
|
||||
return ret;
|
||||
*val = ret;
|
||||
return IIO_VAL_INT;
|
||||
case IIO_CHAN_INFO_SCALE:
|
||||
*val = LTR390_WINDOW_FACTOR;
|
||||
*val2 = LTR390_COUNTS_PER_UVI;
|
||||
return IIO_VAL_FRACTIONAL;
|
||||
default:
|
||||
return -EINVAL;
|
||||
}
|
||||
}
|
||||
|
||||
static const struct iio_info ltr390_info = {
|
||||
.read_raw = ltr390_read_raw,
|
||||
};
|
||||
|
||||
static const struct iio_chan_spec ltr390_channel = {
|
||||
.type = IIO_UVINDEX,
|
||||
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE)
|
||||
};
|
||||
|
||||
static int ltr390_probe(struct i2c_client *client)
|
||||
{
|
||||
struct ltr390_data *data;
|
||||
struct iio_dev *indio_dev;
|
||||
struct device *dev;
|
||||
int ret, part_number;
|
||||
|
||||
dev = &client->dev;
|
||||
indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
|
||||
if (!indio_dev)
|
||||
return -ENOMEM;
|
||||
|
||||
data = iio_priv(indio_dev);
|
||||
|
||||
data->regmap = devm_regmap_init_i2c(client, <r390_regmap_config);
|
||||
if (IS_ERR(data->regmap))
|
||||
return dev_err_probe(dev, PTR_ERR(data->regmap),
|
||||
"regmap initialization failed\n");
|
||||
|
||||
data->client = client;
|
||||
mutex_init(&data->lock);
|
||||
|
||||
indio_dev->info = <r390_info;
|
||||
indio_dev->channels = <r390_channel;
|
||||
indio_dev->num_channels = 1;
|
||||
indio_dev->name = "ltr390";
|
||||
|
||||
ret = regmap_read(data->regmap, LTR390_PART_ID, &part_number);
|
||||
if (ret)
|
||||
return dev_err_probe(dev, ret,
|
||||
"failed to get sensor's part id\n");
|
||||
/* Lower 4 bits of `part_number` change with hardware revisions */
|
||||
if (part_number >> 4 != LTR390_PART_NUMBER_ID)
|
||||
dev_info(dev, "received invalid product id: 0x%x", part_number);
|
||||
dev_dbg(dev, "LTR390, product id: 0x%x\n", part_number);
|
||||
|
||||
/* reset sensor, chip fails to respond to this, so ignore any errors */
|
||||
regmap_set_bits(data->regmap, LTR390_MAIN_CTRL, LTR390_SW_RESET);
|
||||
|
||||
/* Wait for the registers to reset before proceeding */
|
||||
usleep_range(1000, 2000);
|
||||
|
||||
ret = regmap_set_bits(data->regmap, LTR390_MAIN_CTRL,
|
||||
LTR390_SENSOR_ENABLE | LTR390_UVS_MODE);
|
||||
if (ret)
|
||||
return dev_err_probe(dev, ret, "failed to enable the sensor\n");
|
||||
|
||||
return devm_iio_device_register(dev, indio_dev);
|
||||
}
|
||||
|
||||
static const struct i2c_device_id ltr390_id[] = {
|
||||
{ "ltr390" },
|
||||
{ /* Sentinel */ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(i2c, ltr390_id);
|
||||
|
||||
static const struct of_device_id ltr390_of_table[] = {
|
||||
{ .compatible = "liteon,ltr390" },
|
||||
{ /* Sentinel */ }
|
||||
};
|
||||
MODULE_DEVICE_TABLE(of, ltr390_of_table);
|
||||
|
||||
static struct i2c_driver ltr390_driver = {
|
||||
.driver = {
|
||||
.name = "ltr390",
|
||||
.of_match_table = ltr390_of_table,
|
||||
},
|
||||
.probe = ltr390_probe,
|
||||
.id_table = ltr390_id,
|
||||
};
|
||||
module_i2c_driver(ltr390_driver);
|
||||
|
||||
MODULE_AUTHOR("Anshul Dalal <anshulusr@gmail.com>");
|
||||
MODULE_DESCRIPTION("Lite-On LTR390 ALS and UV sensor Driver");
|
||||
MODULE_LICENSE("GPL");
|
Loading…
Reference in New Issue
Block a user