On 25/03/2022 11:30, Shreeya Patel wrote: > From: Zhigang Shi <Zhigang.Shi@xxxxxxxxxx> > > Add initial support for ltrf216a ambient light sensor. > > Datasheet :- > https://gitlab.steamos.cloud/shreeya/iio/-/blob/main/LTR-F216A-QT.pdf > > > Co-developed-by: Shreeya Patel <shreeya.patel@xxxxxxxxxxxxx> > Signed-off-by: Shreeya Patel <shreeya.patel@xxxxxxxxxxxxx> > Signed-off-by: Zhigang Shi <Zhigang.Shi@xxxxxxxxxx> > --- > drivers/iio/light/Kconfig | 10 ++ > drivers/iio/light/Makefile | 1 + > drivers/iio/light/ltrf216a.c | 334 +++++++++++++++++++++++++++++++++++ > 3 files changed, 345 insertions(+) > create mode 100644 drivers/iio/light/ltrf216a.c > > diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig > index a62c7b4b8678..08fa383a8ca7 100644 > --- a/drivers/iio/light/Kconfig > +++ b/drivers/iio/light/Kconfig > @@ -318,6 +318,16 @@ config SENSORS_LM3533 > changes. The ALS-control output values can be set per zone for the > three current output channels. > > +config LTRF216A > + tristate "Liteon LTRF216A Light Sensor" > + depends on I2C > + help > + If you say Y or M here, you get support for Liteon LTRF216A > + Ambient Light Sensor. > + > + If built as a dynamically linked module, it will be called > + ltrf216a. > + > config LTR501 > tristate "LTR-501ALS-01 light sensor" > depends on I2C > diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile > index d10912faf964..8fa91b9fe5b6 100644 > --- a/drivers/iio/light/Makefile > +++ b/drivers/iio/light/Makefile > @@ -30,6 +30,7 @@ obj-$(CONFIG_SENSORS_ISL29028) += isl29028.o > obj-$(CONFIG_ISL29125) += isl29125.o > obj-$(CONFIG_JSA1212) += jsa1212.o > obj-$(CONFIG_SENSORS_LM3533) += lm3533-als.o > +obj-$(CONFIG_LTRF216A) += ltrf216a.o > obj-$(CONFIG_LTR501) += ltr501.o > obj-$(CONFIG_LV0104CS) += lv0104cs.o > obj-$(CONFIG_MAX44000) += max44000.o > diff --git a/drivers/iio/light/ltrf216a.c b/drivers/iio/light/ltrf216a.c > new file mode 100644 > index 000000000000..99295358a7fe > --- /dev/null > +++ b/drivers/iio/light/ltrf216a.c > @@ -0,0 +1,334 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * LTRF216A Ambient Light Sensor > + * > + * Copyright (C) 2021 Lite-On Technology Corp (Singapore) > + * Author: Shi Zhigang <Zhigang.Shi@xxxxxxxxxx> > + * > + * IIO driver for LTRF216A (7-bit I2C slave address 0x53). > + */ > + > +#include <linux/module.h> > +#include <linux/init.h> > +#include <linux/i2c.h> > +#include <linux/mutex.h> > +#include <linux/iio/iio.h> > +#include <linux/iio/sysfs.h> > +#include <linux/pm.h> > +#include <linux/delay.h> > + > +#define LTRF216A_DRV_NAME "ltrf216a" > + > +#define LTRF216A_MAIN_CTRL 0x00 > + > +#define LTRF216A_ALS_MEAS_RATE 0x04 > +#define LTRF216A_MAIN_STATUS 0x07 > +#define LTRF216A_CLEAR_DATA_0 0x0A > + > +#define LTRF216A_ALS_DATA_0 0x0D > + > +static const int int_time_mapping[] = { 400000, 200000, 100000 }; > + > +struct ltrf216a_data { > + struct i2c_client *client; > + u32 int_time; > + u8 int_time_fac; > + u8 als_gain_fac; > + struct mutex mutex; > +}; > + > +/* open air. need to update based on TP transmission rate. */ > +#define WIN_FAC 1 > + > +static const struct iio_chan_spec ltrf216a_channels[] = { > + { > + .type = IIO_LIGHT, > + .info_mask_separate = > + BIT(IIO_CHAN_INFO_PROCESSED) | > + BIT(IIO_CHAN_INFO_INT_TIME), > + } > +}; > + > +static IIO_CONST_ATTR_INT_TIME_AVAIL("0.1 0.2 0.4"); > + > +static struct attribute *ltrf216a_attributes[] = { > + &iio_const_attr_integration_time_available.dev_attr.attr, > + NULL > +}; > + > +static const struct attribute_group ltrf216a_attribute_group = { > + .attrs = ltrf216a_attributes, > +}; > + > +static int ltrf216a_init(struct iio_dev *indio_dev) > +{ > + int ret; > + struct ltrf216a_data *data = iio_priv(indio_dev); > + > + ret = i2c_smbus_read_byte_data(data->client, LTRF216A_MAIN_CTRL); > + if (ret < 0) { > + dev_err(&data->client->dev, "Error reading LTRF216A_MAIN_CTRL\n"); > + return ret; > + } > + > + /* enable sensor */ > + ret |= 0x02; > + ret = i2c_smbus_write_byte_data(data->client, LTRF216A_MAIN_CTRL, ret); > + if (ret < 0) { > + dev_err(&data->client->dev, "Error writing LTRF216A_MAIN_CTRL\n"); > + return ret; > + } > + > + return 0; > +} > + > +static int ltrf216a_disable(struct iio_dev *indio_dev) > +{ > + int ret; > + struct ltrf216a_data *data = iio_priv(indio_dev); > + > + ret = i2c_smbus_write_byte_data(data->client, LTRF216A_MAIN_CTRL, 0); > + if (ret < 0) > + dev_err(&data->client->dev, "Error writing LTRF216A_MAIN_CTRL\n"); > + > + return ret; > +} > + > +static int ltrf216a_set_it_time(struct ltrf216a_data *data, int itime) > +{ > + int i, ret, index = -1; > + u8 reg; > + > + for (i = 0; i < ARRAY_SIZE(int_time_mapping); i++) { > + if (int_time_mapping[i] == itime) { > + index = i; > + break; > + } > + } > + /* Make sure integration time index is valid */ > + if (index < 0) > + return -EINVAL; > + > + if (index == 0) { > + reg = 0x03; > + data->int_time_fac = 4; > + } else if (index == 1) { > + reg = 0x13; > + data->int_time_fac = 2; > + } else { > + reg = (index << 4) | 0x02; > + data->int_time_fac = 1; > + } > + > + ret = i2c_smbus_write_byte_data(data->client, LTRF216A_ALS_MEAS_RATE, reg); > + if (ret < 0) > + return ret; > + > + data->int_time = itime; > + > + return 0; > +} > + > +static int ltrf216a_get_it_time(struct ltrf216a_data *data, int *val, int *val2) > +{ > + *val = 0; > + *val2 = data->int_time; > + > + return IIO_VAL_INT_PLUS_MICRO; > +} > + > +static int ltrf216a_read_data(struct ltrf216a_data *data, u8 addr) > +{ > + int ret; > + int tries = 25; > + int val_0, val_1, val_2; > + > + while (tries--) { > + ret = i2c_smbus_read_byte_data(data->client, LTRF216A_MAIN_STATUS); > + if (ret < 0) > + return ret; > + if (ret & 0x08) > + break; > + msleep(20); > + } > + > + val_0 = i2c_smbus_read_byte_data(data->client, addr); > + val_1 = i2c_smbus_read_byte_data(data->client, addr + 1); > + val_2 = i2c_smbus_read_byte_data(data->client, addr + 2); > + ret = (val_2 << 16) + (val_1 << 8) + val_0; > + > + return ret; > +} > + > +static int ltrf216a_get_lux(struct ltrf216a_data *data) > +{ > + int greendata, cleardata, lux; > + > + greendata = ltrf216a_read_data(data, LTRF216A_ALS_DATA_0); > + cleardata = ltrf216a_read_data(data, LTRF216A_CLEAR_DATA_0); > + > + if (greendata < 0 || cleardata < 0) > + lux = 0; > + else > + lux = greendata * 8 * WIN_FAC / data->als_gain_fac / data->int_time_fac / 10; > + > + return lux; > +} > + > +static int ltrf216a_read_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, int *val, > + int *val2, long mask) > +{ > + int ret; > + struct ltrf216a_data *data = iio_priv(indio_dev); > + > + mutex_lock(&data->mutex); > + > + switch (mask) { > + case IIO_CHAN_INFO_PROCESSED: > + ret = ltrf216a_get_lux(data); > + *val = ret; > + ret = IIO_VAL_INT; > + break; > + case IIO_CHAN_INFO_INT_TIME: > + ret = ltrf216a_get_it_time(data, val, val2); > + break; > + default: > + ret = -EINVAL; > + } > + > + mutex_unlock(&data->mutex); > + > + return ret; > +} > + > +static int ltrf216a_write_raw(struct iio_dev *indio_dev, > + struct iio_chan_spec const *chan, int val, > + int val2, long mask) > +{ > + struct ltrf216a_data *data = iio_priv(indio_dev); > + int ret; > + > + switch (mask) { > + case IIO_CHAN_INFO_INT_TIME: > + if (val != 0) > + return -EINVAL; > + mutex_lock(&data->mutex); > + ret = ltrf216a_set_it_time(data, val2); > + mutex_unlock(&data->mutex); > + return ret; > + default: > + return -EINVAL; > + } > +} > + > +static const struct iio_info ltrf216a_info = { > + .read_raw = ltrf216a_read_raw, > + .write_raw = ltrf216a_write_raw, > + .attrs = <rf216a_attribute_group, > +}; > + > +static int ltrf216a_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + struct ltrf216a_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; > + > + mutex_init(&data->mutex); > + > + indio_dev->info = <rf216a_info; > + indio_dev->name = LTRF216A_DRV_NAME; > + indio_dev->channels = ltrf216a_channels; > + indio_dev->num_channels = ARRAY_SIZE(ltrf216a_channels); > + indio_dev->modes = INDIO_DIRECT_MODE; > + > + ret = ltrf216a_init(indio_dev); > + if (ret < 0) { > + dev_err(&client->dev, "ltrf216a chip init failed\n"); > + return ret; > + } > + data->int_time = 100000; > + data->int_time_fac = 1; > + data->als_gain_fac = 3; > + > + ret = iio_device_register(indio_dev); Use devm- function, assuming no issues with removal-steps (disable will be before iio unregister). > + if (ret < 0) { > + dev_err(&client->dev, "failed to register iio dev\n"); > + goto err_init; > + } > + > + return 0; Blank line. > +err_init: > + ltrf216a_disable(indio_dev); > + return ret; > +} > + Best regards, Krzysztof