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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * AL3010 - Dyna Image Ambient Light Sensor4 *5 * Copyright (c) 2014, Intel Corporation.6 * Copyright (c) 2016, Dyna-Image Corp.7 * Copyright (c) 2020, David Heidelberg, Michał Mirosław, Dmitry Osipenko8 *9 * IIO driver for AL3010 (7-bit I2C slave address 0x1C).10 *11 * TODO: interrupt support, thresholds12 * When the driver will get support for interrupt handling, then interrupt13 * will need to be disabled before turning sensor OFF in order to avoid14 * potential races with the interrupt handling.15 */16 17#include <linux/bitfield.h>18#include <linux/i2c.h>19#include <linux/module.h>20#include <linux/mod_devicetable.h>21 22#include <linux/iio/iio.h>23#include <linux/iio/sysfs.h>24 25#define AL3010_DRV_NAME "al3010"26 27#define AL3010_REG_SYSTEM 0x0028#define AL3010_REG_DATA_LOW 0x0c29#define AL3010_REG_CONFIG 0x1030 31#define AL3010_CONFIG_DISABLE 0x0032#define AL3010_CONFIG_ENABLE 0x0133 34#define AL3010_GAIN_MASK GENMASK(6,4)35 36#define AL3010_SCALE_AVAILABLE "1.1872 0.2968 0.0742 0.018"37 38enum al3xxxx_range {39 AL3XXX_RANGE_1, /* 77806 lx */40 AL3XXX_RANGE_2, /* 19542 lx */41 AL3XXX_RANGE_3, /* 4863 lx */42 AL3XXX_RANGE_4 /* 1216 lx */43};44 45static const int al3010_scales[][2] = {46 {0, 1187200}, {0, 296800}, {0, 74200}, {0, 18600}47};48 49struct al3010_data {50 struct i2c_client *client;51};52 53static const struct iio_chan_spec al3010_channels[] = {54 {55 .type = IIO_LIGHT,56 .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |57 BIT(IIO_CHAN_INFO_SCALE),58 }59};60 61static IIO_CONST_ATTR(in_illuminance_scale_available, AL3010_SCALE_AVAILABLE);62 63static struct attribute *al3010_attributes[] = {64 &iio_const_attr_in_illuminance_scale_available.dev_attr.attr,65 NULL,66};67 68static const struct attribute_group al3010_attribute_group = {69 .attrs = al3010_attributes,70};71 72static int al3010_set_pwr(struct i2c_client *client, bool pwr)73{74 u8 val = pwr ? AL3010_CONFIG_ENABLE : AL3010_CONFIG_DISABLE;75 return i2c_smbus_write_byte_data(client, AL3010_REG_SYSTEM, val);76}77 78static void al3010_set_pwr_off(void *_data)79{80 struct al3010_data *data = _data;81 82 al3010_set_pwr(data->client, false);83}84 85static int al3010_init(struct al3010_data *data)86{87 int ret;88 89 ret = al3010_set_pwr(data->client, true);90 91 if (ret < 0)92 return ret;93 94 ret = i2c_smbus_write_byte_data(data->client, AL3010_REG_CONFIG,95 FIELD_PREP(AL3010_GAIN_MASK,96 AL3XXX_RANGE_3));97 if (ret < 0)98 return ret;99 100 return 0;101}102 103static int al3010_read_raw(struct iio_dev *indio_dev,104 struct iio_chan_spec const *chan, int *val,105 int *val2, long mask)106{107 struct al3010_data *data = iio_priv(indio_dev);108 int ret;109 110 switch (mask) {111 case IIO_CHAN_INFO_RAW:112 /*113 * ALS ADC value is stored in two adjacent registers:114 * - low byte of output is stored at AL3010_REG_DATA_LOW115 * - high byte of output is stored at AL3010_REG_DATA_LOW + 1116 */117 ret = i2c_smbus_read_word_data(data->client,118 AL3010_REG_DATA_LOW);119 if (ret < 0)120 return ret;121 *val = ret;122 return IIO_VAL_INT;123 case IIO_CHAN_INFO_SCALE:124 ret = i2c_smbus_read_byte_data(data->client,125 AL3010_REG_CONFIG);126 if (ret < 0)127 return ret;128 129 ret = FIELD_GET(AL3010_GAIN_MASK, ret);130 *val = al3010_scales[ret][0];131 *val2 = al3010_scales[ret][1];132 133 return IIO_VAL_INT_PLUS_MICRO;134 }135 return -EINVAL;136}137 138static int al3010_write_raw(struct iio_dev *indio_dev,139 struct iio_chan_spec const *chan, int val,140 int val2, long mask)141{142 struct al3010_data *data = iio_priv(indio_dev);143 int i;144 145 switch (mask) {146 case IIO_CHAN_INFO_SCALE:147 for (i = 0; i < ARRAY_SIZE(al3010_scales); i++) {148 if (val != al3010_scales[i][0] ||149 val2 != al3010_scales[i][1])150 continue;151 152 return i2c_smbus_write_byte_data(data->client,153 AL3010_REG_CONFIG,154 FIELD_PREP(AL3010_GAIN_MASK, i));155 }156 break;157 }158 return -EINVAL;159}160 161static const struct iio_info al3010_info = {162 .read_raw = al3010_read_raw,163 .write_raw = al3010_write_raw,164 .attrs = &al3010_attribute_group,165};166 167static int al3010_probe(struct i2c_client *client)168{169 struct al3010_data *data;170 struct iio_dev *indio_dev;171 int ret;172 173 indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));174 if (!indio_dev)175 return -ENOMEM;176 177 data = iio_priv(indio_dev);178 i2c_set_clientdata(client, indio_dev);179 data->client = client;180 181 indio_dev->info = &al3010_info;182 indio_dev->name = AL3010_DRV_NAME;183 indio_dev->channels = al3010_channels;184 indio_dev->num_channels = ARRAY_SIZE(al3010_channels);185 indio_dev->modes = INDIO_DIRECT_MODE;186 187 ret = al3010_init(data);188 if (ret < 0) {189 dev_err(&client->dev, "al3010 chip init failed\n");190 return ret;191 }192 193 ret = devm_add_action_or_reset(&client->dev,194 al3010_set_pwr_off,195 data);196 if (ret < 0)197 return ret;198 199 return devm_iio_device_register(&client->dev, indio_dev);200}201 202static int al3010_suspend(struct device *dev)203{204 return al3010_set_pwr(to_i2c_client(dev), false);205}206 207static int al3010_resume(struct device *dev)208{209 return al3010_set_pwr(to_i2c_client(dev), true);210}211 212static DEFINE_SIMPLE_DEV_PM_OPS(al3010_pm_ops, al3010_suspend, al3010_resume);213 214static const struct i2c_device_id al3010_id[] = {215 {"al3010", },216 {}217};218MODULE_DEVICE_TABLE(i2c, al3010_id);219 220static const struct of_device_id al3010_of_match[] = {221 { .compatible = "dynaimage,al3010", },222 {},223};224MODULE_DEVICE_TABLE(of, al3010_of_match);225 226static struct i2c_driver al3010_driver = {227 .driver = {228 .name = AL3010_DRV_NAME,229 .of_match_table = al3010_of_match,230 .pm = pm_sleep_ptr(&al3010_pm_ops),231 },232 .probe = al3010_probe,233 .id_table = al3010_id,234};235module_i2c_driver(al3010_driver);236 237MODULE_AUTHOR("Daniel Baluta <daniel.baluta@nxp.com>");238MODULE_AUTHOR("David Heidelberg <david@ixit.cz>");239MODULE_DESCRIPTION("AL3010 Ambient Light Sensor driver");240MODULE_LICENSE("GPL v2");241