diff options
Diffstat (limited to 'drivers/iio/light/veml3235.c')
| -rw-r--r-- | drivers/iio/light/veml3235.c | 495 |
1 files changed, 495 insertions, 0 deletions
diff --git a/drivers/iio/light/veml3235.c b/drivers/iio/light/veml3235.c new file mode 100644 index 000000000000..66361c3012a3 --- /dev/null +++ b/drivers/iio/light/veml3235.c @@ -0,0 +1,495 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * VEML3235 Ambient Light Sensor + * + * Copyright (c) 2024, Javier Carrasco <javier.carrasco.cruz@gmail.com> + * + * Datasheet: https://www.vishay.com/docs/80131/veml3235.pdf + * Appnote-80222: https://www.vishay.com/docs/80222/designingveml3235.pdf + */ + +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/iio/iio.h> +#include <linux/module.h> +#include <linux/pm_runtime.h> +#include <linux/regmap.h> +#include <linux/regulator/consumer.h> + +#define VEML3235_REG_CONF 0x00 +#define VEML3235_REG_WH_DATA 0x04 +#define VEML3235_REG_ALS_DATA 0x05 +#define VEML3235_REG_ID 0x09 + +#define VEML3235_CONF_SD BIT(0) +#define VEML3235_CONF_SD0 BIT(15) + +struct veml3235_rf { + struct regmap_field *it; + struct regmap_field *gain; + struct regmap_field *id; +}; + +struct veml3235_data { + struct i2c_client *client; + struct device *dev; + struct regmap *regmap; + struct veml3235_rf rf; +}; + +static const int veml3235_it_times[][2] = { + { 0, 50000 }, + { 0, 100000 }, + { 0, 200000 }, + { 0, 400000 }, + { 0, 800000 }, +}; + +static const int veml3235_scale_vals[] = { 1, 2, 4, 8 }; + +static int veml3235_power_on(struct veml3235_data *data) +{ + int ret; + + ret = regmap_clear_bits(data->regmap, VEML3235_REG_CONF, + VEML3235_CONF_SD | VEML3235_CONF_SD0); + if (ret) + return ret; + + /* Wait 4 ms to let processor & oscillator start correctly */ + fsleep(4000); + + return 0; +} + +static int veml3235_shut_down(struct veml3235_data *data) +{ + return regmap_set_bits(data->regmap, VEML3235_REG_CONF, + VEML3235_CONF_SD | VEML3235_CONF_SD0); +} + +static void veml3235_shut_down_action(void *data) +{ + veml3235_shut_down(data); +} + +enum veml3235_chan { + CH_ALS, + CH_WHITE, +}; + +static const struct iio_chan_spec veml3235_channels[] = { + { + .type = IIO_LIGHT, + .channel = CH_ALS, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME) | + BIT(IIO_CHAN_INFO_SCALE), + .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME) | + BIT(IIO_CHAN_INFO_SCALE), + }, + { + .type = IIO_INTENSITY, + .channel = CH_WHITE, + .modified = 1, + .channel2 = IIO_MOD_LIGHT_BOTH, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), + .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_INT_TIME) | + BIT(IIO_CHAN_INFO_SCALE), + .info_mask_shared_by_all_available = BIT(IIO_CHAN_INFO_INT_TIME) | + BIT(IIO_CHAN_INFO_SCALE), + }, +}; + +static const struct regmap_config veml3235_regmap_config = { + .name = "veml3235_regmap", + .reg_bits = 8, + .val_bits = 16, + .max_register = VEML3235_REG_ID, + .val_format_endian = REGMAP_ENDIAN_LITTLE, +}; + +static int veml3235_get_it(struct veml3235_data *data, int *val, int *val2) +{ + int ret, reg; + + ret = regmap_field_read(data->rf.it, ®); + if (ret) + return ret; + + switch (reg) { + case 0: + *val2 = 50000; + break; + case 1: + *val2 = 100000; + break; + case 2: + *val2 = 200000; + break; + case 3: + *val2 = 400000; + break; + case 4: + *val2 = 800000; + break; + default: + return -EINVAL; + } + + *val = 0; + + return IIO_VAL_INT_PLUS_MICRO; +} + +static int veml3235_set_it(struct iio_dev *indio_dev, int val, int val2) +{ + struct veml3235_data *data = iio_priv(indio_dev); + int ret, new_it; + + if (val) + return -EINVAL; + + switch (val2) { + case 50000: + new_it = 0x00; + break; + case 100000: + new_it = 0x01; + break; + case 200000: + new_it = 0x02; + break; + case 400000: + new_it = 0x03; + break; + case 800000: + new_it = 0x04; + break; + default: + return -EINVAL; + } + + ret = regmap_field_write(data->rf.it, new_it); + if (ret) { + dev_err(data->dev, + "failed to update integration time: %d\n", ret); + return ret; + } + + return 0; +} + +static int veml3235_set_gain(struct iio_dev *indio_dev, int val, int val2) +{ + struct veml3235_data *data = iio_priv(indio_dev); + int ret, new_gain; + + if (val2 != 0) + return -EINVAL; + + switch (val) { + case 1: + new_gain = 0x00; + break; + case 2: + new_gain = 0x01; + break; + case 4: + new_gain = 0x03; + break; + case 8: + new_gain = 0x07; + break; + default: + return -EINVAL; + } + + ret = regmap_field_write(data->rf.gain, new_gain); + if (ret) { + dev_err(data->dev, "failed to set gain: %d\n", ret); + return ret; + } + + return 0; +} + +static int veml3235_get_gain(struct veml3235_data *data, int *val) +{ + int ret, reg; + + ret = regmap_field_read(data->rf.gain, ®); + if (ret) { + dev_err(data->dev, "failed to read gain %d\n", ret); + return ret; + } + + switch (reg & 0x03) { + case 0: + *val = 1; + break; + case 1: + *val = 2; + break; + case 3: + *val = 4; + break; + default: + return -EINVAL; + } + + /* Double gain */ + if (reg & 0x04) + *val *= 2; + + return IIO_VAL_INT; +} + +static int veml3235_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, + int *val2, long mask) +{ + struct veml3235_data *data = iio_priv(indio_dev); + struct regmap *regmap = data->regmap; + int ret, reg; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + switch (chan->type) { + case IIO_LIGHT: + ret = regmap_read(regmap, VEML3235_REG_ALS_DATA, ®); + if (ret < 0) + return ret; + + *val = reg; + return IIO_VAL_INT; + case IIO_INTENSITY: + ret = regmap_read(regmap, VEML3235_REG_WH_DATA, ®); + if (ret < 0) + return ret; + + *val = reg; + return IIO_VAL_INT; + default: + return -EINVAL; + } + case IIO_CHAN_INFO_INT_TIME: + return veml3235_get_it(data, val, val2); + case IIO_CHAN_INFO_SCALE: + return veml3235_get_gain(data, val); + default: + return -EINVAL; + } +} + +static int veml3235_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_INT_TIME: + *vals = (int *)&veml3235_it_times; + *length = 2 * ARRAY_SIZE(veml3235_it_times); + *type = IIO_VAL_INT_PLUS_MICRO; + return IIO_AVAIL_LIST; + case IIO_CHAN_INFO_SCALE: + *vals = (int *)&veml3235_scale_vals; + *length = ARRAY_SIZE(veml3235_scale_vals); + *type = IIO_VAL_INT; + return IIO_AVAIL_LIST; + default: + return -EINVAL; + } +} + +static int veml3235_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + switch (mask) { + case IIO_CHAN_INFO_INT_TIME: + return veml3235_set_it(indio_dev, val, val2); + case IIO_CHAN_INFO_SCALE: + return veml3235_set_gain(indio_dev, val, val2); + } + + return -EINVAL; +} + +static void veml3235_read_id(struct veml3235_data *data) +{ + int ret, reg; + + ret = regmap_field_read(data->rf.id, ®); + if (ret) { + dev_info(data->dev, "failed to read ID\n"); + return; + } + + if (reg != 0x35) + dev_info(data->dev, "Unknown ID %d\n", reg); +} + +static const struct reg_field veml3235_rf_it = + REG_FIELD(VEML3235_REG_CONF, 4, 6); + +static const struct reg_field veml3235_rf_gain = + REG_FIELD(VEML3235_REG_CONF, 11, 13); + +static const struct reg_field veml3235_rf_id = + REG_FIELD(VEML3235_REG_ID, 0, 7); + +static int veml3235_regfield_init(struct veml3235_data *data) +{ + struct regmap *regmap = data->regmap; + struct device *dev = data->dev; + struct regmap_field *rm_field; + struct veml3235_rf *rf = &data->rf; + + rm_field = devm_regmap_field_alloc(dev, regmap, veml3235_rf_it); + if (IS_ERR(rm_field)) + return PTR_ERR(rm_field); + rf->it = rm_field; + + rm_field = devm_regmap_field_alloc(dev, regmap, veml3235_rf_gain); + if (IS_ERR(rm_field)) + return PTR_ERR(rm_field); + rf->gain = rm_field; + + rm_field = devm_regmap_field_alloc(dev, regmap, veml3235_rf_id); + if (IS_ERR(rm_field)) + return PTR_ERR(rm_field); + rf->id = rm_field; + + return 0; +} + +static int veml3235_hw_init(struct iio_dev *indio_dev) +{ + struct veml3235_data *data = iio_priv(indio_dev); + struct device *dev = data->dev; + int ret; + + /* Set gain to 1 and integration time to 100 ms */ + ret = regmap_field_write(data->rf.gain, 0x00); + if (ret) + return dev_err_probe(data->dev, ret, "failed to set gain\n"); + + ret = regmap_field_write(data->rf.it, 0x01); + if (ret) + return dev_err_probe(data->dev, ret, + "failed to set integration time\n"); + + ret = veml3235_power_on(data); + if (ret) + return dev_err_probe(dev, ret, "failed to power on\n"); + + return devm_add_action_or_reset(dev, veml3235_shut_down_action, data); +} + +static const struct iio_info veml3235_info = { + .read_raw = veml3235_read_raw, + .read_avail = veml3235_read_avail, + .write_raw = veml3235_write_raw, +}; + +static int veml3235_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct veml3235_data *data; + struct iio_dev *indio_dev; + struct regmap *regmap; + int ret; + + regmap = devm_regmap_init_i2c(client, &veml3235_regmap_config); + if (IS_ERR(regmap)) + return dev_err_probe(dev, PTR_ERR(regmap), + "failed to setup regmap\n"); + + indio_dev = devm_iio_device_alloc(dev, sizeof(*data)); + if (!indio_dev) + return -ENOMEM; + + data = iio_priv(indio_dev); + i2c_set_clientdata(client, indio_dev); + data->client = client; + data->dev = dev; + data->regmap = regmap; + + ret = veml3235_regfield_init(data); + if (ret) + return dev_err_probe(dev, ret, "failed to init regfield\n"); + + ret = devm_regulator_get_enable(dev, "vdd"); + if (ret) + return dev_err_probe(dev, ret, "failed to enable regulator\n"); + + indio_dev->name = "veml3235"; + indio_dev->channels = veml3235_channels; + indio_dev->num_channels = ARRAY_SIZE(veml3235_channels); + indio_dev->modes = INDIO_DIRECT_MODE; + indio_dev->info = &veml3235_info; + + veml3235_read_id(data); + + ret = veml3235_hw_init(indio_dev); + if (ret < 0) + return ret; + + return devm_iio_device_register(dev, indio_dev); +} + +static int veml3235_runtime_suspend(struct device *dev) +{ + struct veml3235_data *data = iio_priv(dev_get_drvdata(dev)); + int ret; + + ret = veml3235_shut_down(data); + if (ret < 0) + dev_err(data->dev, "failed to suspend: %d\n", ret); + + return ret; +} + +static int veml3235_runtime_resume(struct device *dev) +{ + struct veml3235_data *data = iio_priv(dev_get_drvdata(dev)); + int ret; + + ret = veml3235_power_on(data); + if (ret < 0) + dev_err(data->dev, "failed to resume: %d\n", ret); + + return ret; +} + +static DEFINE_RUNTIME_DEV_PM_OPS(veml3235_pm_ops, veml3235_runtime_suspend, + veml3235_runtime_resume, NULL); + +static const struct of_device_id veml3235_of_match[] = { + { .compatible = "vishay,veml3235" }, + { } +}; +MODULE_DEVICE_TABLE(of, veml3235_of_match); + +static const struct i2c_device_id veml3235_id[] = { + { "veml3235" }, + { } +}; +MODULE_DEVICE_TABLE(i2c, veml3235_id); + +static struct i2c_driver veml3235_driver = { + .driver = { + .name = "veml3235", + .of_match_table = veml3235_of_match, + .pm = pm_ptr(&veml3235_pm_ops), + }, + .probe = veml3235_probe, + .id_table = veml3235_id, +}; +module_i2c_driver(veml3235_driver); + +MODULE_AUTHOR("Javier Carrasco <javier.carrasco.cruz@gmail.com>"); +MODULE_DESCRIPTION("VEML3235 Ambient Light Sensor"); +MODULE_LICENSE("GPL"); |