| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * IIO driver for the light sensor ISL76682. |
| * ISL76682 is Ambient Light Sensor |
| * |
| * Copyright (c) 2023 Marek Vasut <marex@denx.de> |
| */ |
| |
| #include <linux/array_size.h> |
| #include <linux/bits.h> |
| #include <linux/cleanup.h> |
| #include <linux/delay.h> |
| #include <linux/err.h> |
| #include <linux/i2c.h> |
| #include <linux/module.h> |
| #include <linux/mutex.h> |
| #include <linux/regmap.h> |
| #include <linux/types.h> |
| |
| #include <linux/iio/iio.h> |
| |
| #define ISL76682_REG_COMMAND 0x00 |
| |
| #define ISL76682_COMMAND_EN BIT(7) |
| #define ISL76682_COMMAND_MODE_CONTINUOUS BIT(6) |
| #define ISL76682_COMMAND_LIGHT_IR BIT(5) |
| |
| #define ISL76682_COMMAND_RANGE_LUX_1K 0x0 |
| #define ISL76682_COMMAND_RANGE_LUX_4K 0x1 |
| #define ISL76682_COMMAND_RANGE_LUX_16K 0x2 |
| #define ISL76682_COMMAND_RANGE_LUX_64K 0x3 |
| #define ISL76682_COMMAND_RANGE_LUX_MASK GENMASK(1, 0) |
| |
| #define ISL76682_REG_ALSIR_L 0x01 |
| |
| #define ISL76682_REG_ALSIR_U 0x02 |
| |
| #define ISL76682_NUM_REGS (ISL76682_REG_ALSIR_U + 1) |
| |
| #define ISL76682_CONV_TIME_MS 100 |
| #define ISL76682_INT_TIME_US 90000 |
| |
| #define ISL76682_ADC_MAX (BIT(16) - 1) |
| |
| struct isl76682_chip { |
| /* |
| * Lock to synchronize access to device command register |
| * and the content of range variable below. |
| */ |
| struct mutex lock; |
| struct regmap *regmap; |
| u8 range; |
| u8 command; |
| }; |
| |
| struct isl76682_range { |
| u8 range; |
| u32 als; |
| u32 ir; |
| }; |
| |
| static struct isl76682_range isl76682_range_table[] = { |
| { ISL76682_COMMAND_RANGE_LUX_1K, 15000, 10500 }, |
| { ISL76682_COMMAND_RANGE_LUX_4K, 60000, 42000 }, |
| { ISL76682_COMMAND_RANGE_LUX_16K, 240000, 168000 }, |
| { ISL76682_COMMAND_RANGE_LUX_64K, 960000, 673000 } |
| }; |
| |
| static int isl76682_get(struct isl76682_chip *chip, bool mode_ir, int *data) |
| { |
| u8 command; |
| int ret; |
| |
| command = ISL76682_COMMAND_EN | ISL76682_COMMAND_MODE_CONTINUOUS | |
| chip->range; |
| |
| if (mode_ir) |
| command |= ISL76682_COMMAND_LIGHT_IR; |
| |
| if (command != chip->command) { |
| ret = regmap_write(chip->regmap, ISL76682_REG_COMMAND, command); |
| if (ret) |
| return ret; |
| |
| /* Need to wait for conversion time if ALS/IR mode enabled */ |
| msleep(ISL76682_CONV_TIME_MS); |
| |
| chip->command = command; |
| } |
| |
| ret = regmap_bulk_read(chip->regmap, ISL76682_REG_ALSIR_L, data, 2); |
| *data &= ISL76682_ADC_MAX; |
| return ret; |
| } |
| |
| static int isl76682_write_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, |
| int val, int val2, long mask) |
| { |
| struct isl76682_chip *chip = iio_priv(indio_dev); |
| int i; |
| |
| if (mask != IIO_CHAN_INFO_SCALE) |
| return -EINVAL; |
| |
| if (val != 0) |
| return -EINVAL; |
| |
| for (i = 0; i < ARRAY_SIZE(isl76682_range_table); i++) { |
| if (chan->type == IIO_LIGHT && val2 != isl76682_range_table[i].als) |
| continue; |
| if (chan->type == IIO_INTENSITY && val2 != isl76682_range_table[i].ir) |
| continue; |
| |
| scoped_guard(mutex, &chip->lock) |
| chip->range = isl76682_range_table[i].range; |
| return 0; |
| } |
| |
| return -EINVAL; |
| } |
| |
| static int isl76682_read_raw(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, |
| int *val, int *val2, long mask) |
| { |
| struct isl76682_chip *chip = iio_priv(indio_dev); |
| int ret; |
| int i; |
| |
| guard(mutex)(&chip->lock); |
| |
| switch (mask) { |
| case IIO_CHAN_INFO_RAW: |
| switch (chan->type) { |
| case IIO_LIGHT: |
| ret = isl76682_get(chip, false, val); |
| return (ret < 0) ? ret : IIO_VAL_INT; |
| case IIO_INTENSITY: |
| ret = isl76682_get(chip, true, val); |
| return (ret < 0) ? ret : IIO_VAL_INT; |
| default: |
| return -EINVAL; |
| } |
| case IIO_CHAN_INFO_SCALE: |
| for (i = 0; i < ARRAY_SIZE(isl76682_range_table); i++) { |
| if (chip->range != isl76682_range_table[i].range) |
| continue; |
| |
| *val = 0; |
| switch (chan->type) { |
| case IIO_LIGHT: |
| *val2 = isl76682_range_table[i].als; |
| return IIO_VAL_INT_PLUS_MICRO; |
| case IIO_INTENSITY: |
| *val2 = isl76682_range_table[i].ir; |
| return IIO_VAL_INT_PLUS_MICRO; |
| default: |
| return -EINVAL; |
| } |
| } |
| return -EINVAL; |
| case IIO_CHAN_INFO_INT_TIME: |
| *val = 0; |
| *val2 = ISL76682_INT_TIME_US; |
| return IIO_VAL_INT_PLUS_MICRO; |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| static int illuminance_scale_available[] = { |
| 0, 15000, |
| 0, 60000, |
| 0, 240000, |
| 0, 960000, |
| }; |
| |
| static int intensity_scale_available[] = { |
| 0, 10500, |
| 0, 42000, |
| 0, 168000, |
| 0, 673000, |
| }; |
| |
| static int isl76682_read_avail(struct iio_dev *indio_dev, |
| struct iio_chan_spec const *chan, |
| const int **vals, int *type, |
| int *length, long mask) |
| { |
| switch (mask) { |
| case IIO_CHAN_INFO_SCALE: |
| switch (chan->type) { |
| case IIO_LIGHT: |
| *vals = illuminance_scale_available; |
| *length = ARRAY_SIZE(illuminance_scale_available); |
| *type = IIO_VAL_INT_PLUS_MICRO; |
| return IIO_AVAIL_LIST; |
| case IIO_INTENSITY: |
| *vals = intensity_scale_available; |
| *length = ARRAY_SIZE(intensity_scale_available); |
| *type = IIO_VAL_INT_PLUS_MICRO; |
| return IIO_AVAIL_LIST; |
| default: |
| return -EINVAL; |
| } |
| default: |
| return -EINVAL; |
| } |
| } |
| |
| static const struct iio_chan_spec isl76682_channels[] = { |
| { |
| .type = IIO_LIGHT, |
| .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | |
| 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), |
| }, { |
| .type = IIO_INTENSITY, |
| .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | |
| 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), |
| } |
| }; |
| |
| static const struct iio_info isl76682_info = { |
| .read_avail = isl76682_read_avail, |
| .read_raw = isl76682_read_raw, |
| .write_raw = isl76682_write_raw, |
| }; |
| |
| static int isl76682_clear_configure_reg(struct isl76682_chip *chip) |
| { |
| struct device *dev = regmap_get_device(chip->regmap); |
| int ret; |
| |
| ret = regmap_write(chip->regmap, ISL76682_REG_COMMAND, 0x0); |
| if (ret < 0) |
| dev_err(dev, "Error %d clearing the CONFIGURE register\n", ret); |
| |
| /* |
| * In the success case, the command register was zeroed out. |
| * |
| * In the error case, we do not know in which state the command |
| * register is, so we assume it is zeroed out, so that it would |
| * be reprogrammed at the next data read out, and at that time |
| * we hope it would be reprogrammed successfully. That is very |
| * much a best effort approach. |
| */ |
| chip->command = 0; |
| |
| return ret; |
| } |
| |
| static void isl76682_reset_action(void *chip) |
| { |
| isl76682_clear_configure_reg(chip); |
| } |
| |
| static bool isl76682_is_volatile_reg(struct device *dev, unsigned int reg) |
| { |
| switch (reg) { |
| case ISL76682_REG_ALSIR_L: |
| case ISL76682_REG_ALSIR_U: |
| return true; |
| default: |
| return false; |
| } |
| } |
| |
| static const struct regmap_config isl76682_regmap_config = { |
| .reg_bits = 8, |
| .val_bits = 8, |
| .volatile_reg = isl76682_is_volatile_reg, |
| .max_register = ISL76682_NUM_REGS - 1, |
| .num_reg_defaults_raw = ISL76682_NUM_REGS, |
| .cache_type = REGCACHE_FLAT, |
| }; |
| |
| static int isl76682_probe(struct i2c_client *client) |
| { |
| struct device *dev = &client->dev; |
| struct isl76682_chip *chip; |
| struct iio_dev *indio_dev; |
| int ret; |
| |
| indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip)); |
| if (!indio_dev) |
| return -ENOMEM; |
| |
| chip = iio_priv(indio_dev); |
| |
| mutex_init(&chip->lock); |
| |
| chip->regmap = devm_regmap_init_i2c(client, &isl76682_regmap_config); |
| ret = PTR_ERR_OR_ZERO(chip->regmap); |
| if (ret) |
| return dev_err_probe(dev, ret, "Error initializing regmap\n"); |
| |
| chip->range = ISL76682_COMMAND_RANGE_LUX_1K; |
| |
| ret = isl76682_clear_configure_reg(chip); |
| if (ret < 0) |
| return ret; |
| |
| ret = devm_add_action_or_reset(dev, isl76682_reset_action, chip); |
| if (ret) |
| return ret; |
| |
| indio_dev->info = &isl76682_info; |
| indio_dev->channels = isl76682_channels; |
| indio_dev->num_channels = ARRAY_SIZE(isl76682_channels); |
| indio_dev->name = "isl76682"; |
| indio_dev->modes = INDIO_DIRECT_MODE; |
| |
| return devm_iio_device_register(dev, indio_dev); |
| } |
| |
| static const struct i2c_device_id isl76682_id[] = { |
| { "isl76682" }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(i2c, isl76682_id); |
| |
| static const struct of_device_id isl76682_of_match[] = { |
| { .compatible = "isil,isl76682" }, |
| { } |
| }; |
| MODULE_DEVICE_TABLE(of, isl76682_of_match); |
| |
| static struct i2c_driver isl76682_driver = { |
| .driver = { |
| .name = "isl76682", |
| .of_match_table = isl76682_of_match, |
| }, |
| .probe = isl76682_probe, |
| .id_table = isl76682_id, |
| }; |
| module_i2c_driver(isl76682_driver); |
| |
| MODULE_DESCRIPTION("ISL76682 Ambient Light Sensor driver"); |
| MODULE_LICENSE("GPL"); |
| MODULE_AUTHOR("Marek Vasut <marex@denx.de>"); |