// SPDX-License-Identifier: GPL-2.0+ /* * VEML3235 Ambient Light Sensor * * Copyright (c) 2024, Javier Carrasco * * Datasheet: https://www.vishay.com/docs/80131/veml3235.pdf * Appnote-80222: https://www.vishay.com/docs/80222/designingveml3235.pdf */ #include #include #include #include #include #include #include #include #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; struct iio_gts gts; }; static const struct iio_itime_sel_mul veml3235_it_sel[] = { GAIN_SCALE_ITIME_US(50000, 0, 1), GAIN_SCALE_ITIME_US(100000, 1, 2), GAIN_SCALE_ITIME_US(200000, 2, 4), GAIN_SCALE_ITIME_US(400000, 3, 8), GAIN_SCALE_ITIME_US(800000, 4, 16), }; /* * The MSB (DG) doubles the value of the rest of the field, which leads to * two possible combinations to obtain gain = 2 and gain = 4. The gain * handling can be simplified by restricting DG = 1 to the only gain that * really requires it, gain = 8. Note that "X10" is a reserved value. */ #define VEML3235_SEL_GAIN_X1 0 #define VEML3235_SEL_GAIN_X2 1 #define VEML3235_SEL_GAIN_X4 3 #define VEML3235_SEL_GAIN_X8 7 static const struct iio_gain_sel_pair veml3235_gain_sel[] = { GAIN_SCALE_GAIN(1, VEML3235_SEL_GAIN_X1), GAIN_SCALE_GAIN(2, VEML3235_SEL_GAIN_X2), GAIN_SCALE_GAIN(4, VEML3235_SEL_GAIN_X4), GAIN_SCALE_GAIN(8, VEML3235_SEL_GAIN_X8), }; 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_range veml3235_readable_ranges[] = { regmap_reg_range(VEML3235_REG_CONF, VEML3235_REG_ID), }; static const struct regmap_access_table veml3235_readable_table = { .yes_ranges = veml3235_readable_ranges, .n_yes_ranges = ARRAY_SIZE(veml3235_readable_ranges), }; static const struct regmap_range veml3235_writable_ranges[] = { regmap_reg_range(VEML3235_REG_CONF, VEML3235_REG_CONF), }; static const struct regmap_access_table veml3235_writable_table = { .yes_ranges = veml3235_writable_ranges, .n_yes_ranges = ARRAY_SIZE(veml3235_writable_ranges), }; static const struct regmap_range veml3235_volatile_ranges[] = { regmap_reg_range(VEML3235_REG_WH_DATA, VEML3235_REG_ALS_DATA), }; static const struct regmap_access_table veml3235_volatile_table = { .yes_ranges = veml3235_volatile_ranges, .n_yes_ranges = ARRAY_SIZE(veml3235_volatile_ranges), }; 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, .rd_table = &veml3235_readable_table, .wr_table = &veml3235_writable_table, .volatile_table = &veml3235_volatile_table, .cache_type = REGCACHE_RBTREE, }; static int veml3235_get_it(struct veml3235_data *data, int *val, int *val2) { int ret, it_idx; ret = regmap_field_read(data->rf.it, &it_idx); if (ret) return ret; ret = iio_gts_find_int_time_by_sel(&data->gts, it_idx); if (ret < 0) return ret; *val2 = ret; *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, gain_idx, it_idx, new_gain, prev_gain, prev_it; bool in_range; if (val || !iio_gts_valid_time(&data->gts, val2)) return -EINVAL; ret = regmap_field_read(data->rf.it, &it_idx); if (ret) return ret; ret = regmap_field_read(data->rf.gain, &gain_idx); if (ret) return ret; prev_it = iio_gts_find_int_time_by_sel(&data->gts, it_idx); if (prev_it < 0) return prev_it; if (prev_it == val2) return 0; prev_gain = iio_gts_find_gain_by_sel(&data->gts, gain_idx); if (prev_gain < 0) return prev_gain; ret = iio_gts_find_new_gain_by_gain_time_min(&data->gts, prev_gain, prev_it, val2, &new_gain, &in_range); if (ret) return ret; if (!in_range) dev_dbg(data->dev, "Optimal gain out of range\n"); ret = iio_gts_find_sel_by_int_time(&data->gts, val2); if (ret < 0) return ret; ret = regmap_field_write(data->rf.it, ret); if (ret) return ret; ret = iio_gts_find_sel_by_gain(&data->gts, new_gain); if (ret < 0) return ret; return regmap_field_write(data->rf.gain, ret); } static int veml3235_set_scale(struct iio_dev *indio_dev, int val, int val2) { struct veml3235_data *data = iio_priv(indio_dev); int ret, it_idx, gain_sel, time_sel; ret = regmap_field_read(data->rf.it, &it_idx); if (ret) return ret; ret = iio_gts_find_gain_time_sel_for_scale(&data->gts, val, val2, &gain_sel, &time_sel); if (ret) return ret; ret = regmap_field_write(data->rf.it, time_sel); if (ret) return ret; return regmap_field_write(data->rf.gain, gain_sel); } static int veml3235_get_scale(struct veml3235_data *data, int *val, int *val2) { int gain, it, reg, ret; ret = regmap_field_read(data->rf.gain, ®); if (ret) { dev_err(data->dev, "failed to read gain %d\n", ret); return ret; } gain = iio_gts_find_gain_by_sel(&data->gts, reg); if (gain < 0) return gain; ret = regmap_field_read(data->rf.it, ®); if (ret) { dev_err(data->dev, "failed to read integration time %d\n", ret); return ret; } it = iio_gts_find_int_time_by_sel(&data->gts, reg); if (it < 0) return it; ret = iio_gts_get_scale(&data->gts, gain, it, val, val2); if (ret) return ret; return IIO_VAL_INT_PLUS_NANO; } 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_scale(data, val, val2); 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) { struct veml3235_data *data = iio_priv(indio_dev); switch (mask) { case IIO_CHAN_INFO_INT_TIME: return iio_gts_avail_times(&data->gts, vals, type, length); case IIO_CHAN_INFO_SCALE: return iio_gts_all_avail_scales(&data->gts, vals, type, length); default: return -EINVAL; } } static int veml3235_write_raw_get_fmt(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, long mask) { switch (mask) { case IIO_CHAN_INFO_SCALE: return IIO_VAL_INT_PLUS_NANO; case IIO_CHAN_INFO_INT_TIME: return IIO_VAL_INT_PLUS_MICRO; 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_scale(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; ret = devm_iio_init_iio_gts(data->dev, 0, 272640000, veml3235_gain_sel, ARRAY_SIZE(veml3235_gain_sel), veml3235_it_sel, ARRAY_SIZE(veml3235_it_sel), &data->gts); if (ret) return dev_err_probe(data->dev, ret, "failed to init iio gts\n"); /* 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, .write_raw_get_fmt = veml3235_write_raw_get_fmt, }; 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 "); MODULE_DESCRIPTION("VEML3235 Ambient Light Sensor"); MODULE_LICENSE("GPL"); MODULE_IMPORT_NS("IIO_GTS_HELPER");