// SPDX-License-Identifier: GPL-2.0+ /* * VEML6030 Ambient Light Sensor * * Copyright (c) 2019, Rishi Gupta * * Datasheet: https://www.vishay.com/docs/84366/veml6030.pdf * Appnote-84367: https://www.vishay.com/docs/84367/designingveml6030.pdf */ #include #include #include #include #include #include #include #include #include /* Device registers */ #define VEML6030_REG_ALS_CONF 0x00 #define VEML6030_REG_ALS_WH 0x01 #define VEML6030_REG_ALS_WL 0x02 #define VEML6030_REG_ALS_PSM 0x03 #define VEML6030_REG_ALS_DATA 0x04 #define VEML6030_REG_WH_DATA 0x05 #define VEML6030_REG_ALS_INT 0x06 /* Bit masks for specific functionality */ #define VEML6030_ALS_IT GENMASK(9, 6) #define VEML6030_PSM GENMASK(2, 1) #define VEML6030_ALS_PERS GENMASK(5, 4) #define VEML6030_ALS_GAIN GENMASK(12, 11) #define VEML6030_PSM_EN BIT(0) #define VEML6030_INT_TH_LOW BIT(15) #define VEML6030_INT_TH_HIGH BIT(14) #define VEML6030_ALS_INT_EN BIT(1) #define VEML6030_ALS_SD BIT(0) /* * The resolution depends on both gain and integration time. The * cur_resolution stores one of the resolution mentioned in the * table during startup and gets updated whenever integration time * or gain is changed. * * Table 'resolution and maximum detection range' in appnote 84367 * is visualized as a 2D array. The cur_gain stores index of gain * in this table (0-3) while the cur_integration_time holds index * of integration time (0-5). */ struct veml6030_data { struct i2c_client *client; struct regmap *regmap; int cur_resolution; int cur_gain; int cur_integration_time; }; /* Integration time available in seconds */ static IIO_CONST_ATTR(in_illuminance_integration_time_available, "0.025 0.05 0.1 0.2 0.4 0.8"); /* * Scale is 1/gain. Value 0.125 is ALS gain x (1/8), 0.25 is * ALS gain x (1/4), 1.0 = ALS gain x 1 and 2.0 is ALS gain x 2. */ static IIO_CONST_ATTR(in_illuminance_scale_available, "0.125 0.25 1.0 2.0"); static struct attribute *veml6030_attributes[] = { &iio_const_attr_in_illuminance_integration_time_available.dev_attr.attr, &iio_const_attr_in_illuminance_scale_available.dev_attr.attr, NULL }; static const struct attribute_group veml6030_attr_group = { .attrs = veml6030_attributes, }; /* * Persistence = 1/2/4/8 x integration time * Minimum time for which light readings must stay above configured * threshold to assert the interrupt. */ static const char * const period_values[] = { "0.1 0.2 0.4 0.8", "0.2 0.4 0.8 1.6", "0.4 0.8 1.6 3.2", "0.8 1.6 3.2 6.4", "0.05 0.1 0.2 0.4", "0.025 0.050 0.1 0.2" }; /* * Return list of valid period values in seconds corresponding to * the currently active integration time. */ static ssize_t in_illuminance_period_available_show(struct device *dev, struct device_attribute *attr, char *buf) { struct veml6030_data *data = iio_priv(dev_to_iio_dev(dev)); int ret, reg, x; ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, ®); if (ret) { dev_err(&data->client->dev, "can't read als conf register %d\n", ret); return ret; } ret = ((reg >> 6) & 0xF); switch (ret) { case 0: case 1: case 2: case 3: x = ret; break; case 8: x = 4; break; case 12: x = 5; break; default: return -EINVAL; } return sysfs_emit(buf, "%s\n", period_values[x]); } static IIO_DEVICE_ATTR_RO(in_illuminance_period_available, 0); static struct attribute *veml6030_event_attributes[] = { &iio_dev_attr_in_illuminance_period_available.dev_attr.attr, NULL }; static const struct attribute_group veml6030_event_attr_group = { .attrs = veml6030_event_attributes, }; static int veml6030_als_pwr_on(struct veml6030_data *data) { return regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF, VEML6030_ALS_SD, 0); } static int veml6030_als_shut_down(struct veml6030_data *data) { return regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF, VEML6030_ALS_SD, 1); } static void veml6030_als_shut_down_action(void *data) { veml6030_als_shut_down(data); } static const struct iio_event_spec veml6030_event_spec[] = { { .type = IIO_EV_TYPE_THRESH, .dir = IIO_EV_DIR_RISING, .mask_separate = BIT(IIO_EV_INFO_VALUE), }, { .type = IIO_EV_TYPE_THRESH, .dir = IIO_EV_DIR_FALLING, .mask_separate = BIT(IIO_EV_INFO_VALUE), }, { .type = IIO_EV_TYPE_THRESH, .dir = IIO_EV_DIR_EITHER, .mask_separate = BIT(IIO_EV_INFO_PERIOD) | BIT(IIO_EV_INFO_ENABLE), }, }; /* Channel number */ enum veml6030_chan { CH_ALS, CH_WHITE, }; static const struct iio_chan_spec veml6030_channels[] = { { .type = IIO_LIGHT, .channel = CH_ALS, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_PROCESSED) | BIT(IIO_CHAN_INFO_INT_TIME) | BIT(IIO_CHAN_INFO_SCALE), .event_spec = veml6030_event_spec, .num_event_specs = ARRAY_SIZE(veml6030_event_spec), }, { .type = IIO_INTENSITY, .channel = CH_WHITE, .modified = 1, .channel2 = IIO_MOD_LIGHT_BOTH, .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_PROCESSED), }, }; static const struct regmap_config veml6030_regmap_config = { .name = "veml6030_regmap", .reg_bits = 8, .val_bits = 16, .max_register = VEML6030_REG_ALS_INT, .val_format_endian = REGMAP_ENDIAN_LITTLE, }; static int veml6030_get_intgrn_tm(struct iio_dev *indio_dev, int *val, int *val2) { int ret, reg; struct veml6030_data *data = iio_priv(indio_dev); ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, ®); if (ret) { dev_err(&data->client->dev, "can't read als conf register %d\n", ret); return ret; } switch ((reg >> 6) & 0xF) { case 0: *val2 = 100000; break; case 1: *val2 = 200000; break; case 2: *val2 = 400000; break; case 3: *val2 = 800000; break; case 8: *val2 = 50000; break; case 12: *val2 = 25000; break; default: return -EINVAL; } *val = 0; return IIO_VAL_INT_PLUS_MICRO; } static int veml6030_set_intgrn_tm(struct iio_dev *indio_dev, int val, int val2) { int ret, new_int_time, int_idx; struct veml6030_data *data = iio_priv(indio_dev); if (val) return -EINVAL; switch (val2) { case 25000: new_int_time = 0x300; int_idx = 5; break; case 50000: new_int_time = 0x200; int_idx = 4; break; case 100000: new_int_time = 0x00; int_idx = 3; break; case 200000: new_int_time = 0x40; int_idx = 2; break; case 400000: new_int_time = 0x80; int_idx = 1; break; case 800000: new_int_time = 0xC0; int_idx = 0; break; default: return -EINVAL; } ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF, VEML6030_ALS_IT, new_int_time); if (ret) { dev_err(&data->client->dev, "can't update als integration time %d\n", ret); return ret; } /* * Cache current integration time and update resolution. For every * increase in integration time to next level, resolution is halved * and vice-versa. */ if (data->cur_integration_time < int_idx) data->cur_resolution <<= int_idx - data->cur_integration_time; else if (data->cur_integration_time > int_idx) data->cur_resolution >>= data->cur_integration_time - int_idx; data->cur_integration_time = int_idx; return ret; } static int veml6030_read_persistence(struct iio_dev *indio_dev, int *val, int *val2) { int ret, reg, period, x, y; struct veml6030_data *data = iio_priv(indio_dev); ret = veml6030_get_intgrn_tm(indio_dev, &x, &y); if (ret < 0) return ret; ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, ®); if (ret) { dev_err(&data->client->dev, "can't read als conf register %d\n", ret); } /* integration time multiplied by 1/2/4/8 */ period = y * (1 << ((reg >> 4) & 0x03)); *val = period / 1000000; *val2 = period % 1000000; return IIO_VAL_INT_PLUS_MICRO; } static int veml6030_write_persistence(struct iio_dev *indio_dev, int val, int val2) { int ret, period, x, y; struct veml6030_data *data = iio_priv(indio_dev); ret = veml6030_get_intgrn_tm(indio_dev, &x, &y); if (ret < 0) return ret; if (!val) { period = val2 / y; } else { if ((val == 1) && (val2 == 600000)) period = 1600000 / y; else if ((val == 3) && (val2 == 200000)) period = 3200000 / y; else if ((val == 6) && (val2 == 400000)) period = 6400000 / y; else period = -1; } if (period <= 0 || period > 8 || hweight8(period) != 1) return -EINVAL; ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF, VEML6030_ALS_PERS, (ffs(period) - 1) << 4); if (ret) dev_err(&data->client->dev, "can't set persistence value %d\n", ret); return ret; } static int veml6030_set_als_gain(struct iio_dev *indio_dev, int val, int val2) { int ret, new_gain, gain_idx; struct veml6030_data *data = iio_priv(indio_dev); if (val == 0 && val2 == 125000) { new_gain = 0x1000; /* 0x02 << 11 */ gain_idx = 3; } else if (val == 0 && val2 == 250000) { new_gain = 0x1800; gain_idx = 2; } else if (val == 1 && val2 == 0) { new_gain = 0x00; gain_idx = 1; } else if (val == 2 && val2 == 0) { new_gain = 0x800; gain_idx = 0; } else { return -EINVAL; } ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF, VEML6030_ALS_GAIN, new_gain); if (ret) { dev_err(&data->client->dev, "can't set als gain %d\n", ret); return ret; } /* * Cache currently set gain & update resolution. For every * increase in the gain to next level, resolution is halved * and vice-versa. */ if (data->cur_gain < gain_idx) data->cur_resolution <<= gain_idx - data->cur_gain; else if (data->cur_gain > gain_idx) data->cur_resolution >>= data->cur_gain - gain_idx; data->cur_gain = gain_idx; return ret; } static int veml6030_get_als_gain(struct iio_dev *indio_dev, int *val, int *val2) { int ret, reg; struct veml6030_data *data = iio_priv(indio_dev); ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, ®); if (ret) { dev_err(&data->client->dev, "can't read als conf register %d\n", ret); return ret; } switch ((reg >> 11) & 0x03) { case 0: *val = 1; *val2 = 0; break; case 1: *val = 2; *val2 = 0; break; case 2: *val = 0; *val2 = 125000; break; case 3: *val = 0; *val2 = 250000; break; default: return -EINVAL; } return IIO_VAL_INT_PLUS_MICRO; } static int veml6030_read_thresh(struct iio_dev *indio_dev, int *val, int *val2, int dir) { int ret, reg; struct veml6030_data *data = iio_priv(indio_dev); if (dir == IIO_EV_DIR_RISING) ret = regmap_read(data->regmap, VEML6030_REG_ALS_WH, ®); else ret = regmap_read(data->regmap, VEML6030_REG_ALS_WL, ®); if (ret) { dev_err(&data->client->dev, "can't read als threshold value %d\n", ret); return ret; } *val = reg & 0xffff; return IIO_VAL_INT; } static int veml6030_write_thresh(struct iio_dev *indio_dev, int val, int val2, int dir) { int ret; struct veml6030_data *data = iio_priv(indio_dev); if (val > 0xFFFF || val < 0 || val2) return -EINVAL; if (dir == IIO_EV_DIR_RISING) { ret = regmap_write(data->regmap, VEML6030_REG_ALS_WH, val); if (ret) dev_err(&data->client->dev, "can't set high threshold %d\n", ret); } else { ret = regmap_write(data->regmap, VEML6030_REG_ALS_WL, val); if (ret) dev_err(&data->client->dev, "can't set low threshold %d\n", ret); } return ret; } /* * Provide both raw as well as light reading in lux. * light (in lux) = resolution * raw reading */ static int veml6030_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { int ret, reg; struct veml6030_data *data = iio_priv(indio_dev); struct regmap *regmap = data->regmap; struct device *dev = &data->client->dev; switch (mask) { case IIO_CHAN_INFO_RAW: case IIO_CHAN_INFO_PROCESSED: switch (chan->type) { case IIO_LIGHT: ret = regmap_read(regmap, VEML6030_REG_ALS_DATA, ®); if (ret < 0) { dev_err(dev, "can't read als data %d\n", ret); return ret; } if (mask == IIO_CHAN_INFO_PROCESSED) { *val = (reg * data->cur_resolution) / 10000; *val2 = (reg * data->cur_resolution) % 10000 * 100; return IIO_VAL_INT_PLUS_MICRO; } *val = reg; return IIO_VAL_INT; case IIO_INTENSITY: ret = regmap_read(regmap, VEML6030_REG_WH_DATA, ®); if (ret < 0) { dev_err(dev, "can't read white data %d\n", ret); return ret; } if (mask == IIO_CHAN_INFO_PROCESSED) { *val = (reg * data->cur_resolution) / 10000; *val2 = (reg * data->cur_resolution) % 10000; return IIO_VAL_INT_PLUS_MICRO; } *val = reg; return IIO_VAL_INT; default: return -EINVAL; } case IIO_CHAN_INFO_INT_TIME: if (chan->type == IIO_LIGHT) return veml6030_get_intgrn_tm(indio_dev, val, val2); return -EINVAL; case IIO_CHAN_INFO_SCALE: if (chan->type == IIO_LIGHT) return veml6030_get_als_gain(indio_dev, val, val2); return -EINVAL; default: return -EINVAL; } } static int veml6030_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: switch (chan->type) { case IIO_LIGHT: return veml6030_set_intgrn_tm(indio_dev, val, val2); default: return -EINVAL; } case IIO_CHAN_INFO_SCALE: switch (chan->type) { case IIO_LIGHT: return veml6030_set_als_gain(indio_dev, val, val2); default: return -EINVAL; } default: return -EINVAL; } } static int veml6030_read_event_val(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, enum iio_event_type type, enum iio_event_direction dir, enum iio_event_info info, int *val, int *val2) { switch (info) { case IIO_EV_INFO_VALUE: switch (dir) { case IIO_EV_DIR_RISING: case IIO_EV_DIR_FALLING: return veml6030_read_thresh(indio_dev, val, val2, dir); default: return -EINVAL; } break; case IIO_EV_INFO_PERIOD: return veml6030_read_persistence(indio_dev, val, val2); default: return -EINVAL; } } static int veml6030_write_event_val(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, enum iio_event_type type, enum iio_event_direction dir, enum iio_event_info info, int val, int val2) { switch (info) { case IIO_EV_INFO_VALUE: return veml6030_write_thresh(indio_dev, val, val2, dir); case IIO_EV_INFO_PERIOD: return veml6030_write_persistence(indio_dev, val, val2); default: return -EINVAL; } } static int veml6030_read_interrupt_config(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, enum iio_event_type type, enum iio_event_direction dir) { int ret, reg; struct veml6030_data *data = iio_priv(indio_dev); ret = regmap_read(data->regmap, VEML6030_REG_ALS_CONF, ®); if (ret) { dev_err(&data->client->dev, "can't read als conf register %d\n", ret); return ret; } if (reg & VEML6030_ALS_INT_EN) return 1; else return 0; } /* * Sensor should not be measuring light when interrupt is configured. * Therefore correct sequence to configure interrupt functionality is: * shut down -> enable/disable interrupt -> power on * * state = 1 enables interrupt, state = 0 disables interrupt */ static int veml6030_write_interrupt_config(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, enum iio_event_type type, enum iio_event_direction dir, int state) { int ret; struct veml6030_data *data = iio_priv(indio_dev); if (state < 0 || state > 1) return -EINVAL; ret = veml6030_als_shut_down(data); if (ret < 0) { dev_err(&data->client->dev, "can't disable als to configure interrupt %d\n", ret); return ret; } /* enable interrupt + power on */ ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_CONF, VEML6030_ALS_INT_EN | VEML6030_ALS_SD, state << 1); if (ret) dev_err(&data->client->dev, "can't enable interrupt & poweron als %d\n", ret); return ret; } static const struct iio_info veml6030_info = { .read_raw = veml6030_read_raw, .write_raw = veml6030_write_raw, .read_event_value = veml6030_read_event_val, .write_event_value = veml6030_write_event_val, .read_event_config = veml6030_read_interrupt_config, .write_event_config = veml6030_write_interrupt_config, .attrs = &veml6030_attr_group, .event_attrs = &veml6030_event_attr_group, }; static const struct iio_info veml6030_info_no_irq = { .read_raw = veml6030_read_raw, .write_raw = veml6030_write_raw, .attrs = &veml6030_attr_group, }; static irqreturn_t veml6030_event_handler(int irq, void *private) { int ret, reg, evtdir; struct iio_dev *indio_dev = private; struct veml6030_data *data = iio_priv(indio_dev); ret = regmap_read(data->regmap, VEML6030_REG_ALS_INT, ®); if (ret) { dev_err(&data->client->dev, "can't read als interrupt register %d\n", ret); return IRQ_HANDLED; } /* Spurious interrupt handling */ if (!(reg & (VEML6030_INT_TH_HIGH | VEML6030_INT_TH_LOW))) return IRQ_NONE; if (reg & VEML6030_INT_TH_HIGH) evtdir = IIO_EV_DIR_RISING; else evtdir = IIO_EV_DIR_FALLING; iio_push_event(indio_dev, IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0, IIO_EV_TYPE_THRESH, evtdir), iio_get_time_ns(indio_dev)); return IRQ_HANDLED; } /* * Set ALS gain to 1/8, integration time to 100 ms, PSM to mode 2, * persistence to 1 x integration time and the threshold * interrupt disabled by default. First shutdown the sensor, * update registers and then power on the sensor. */ static int veml6030_hw_init(struct iio_dev *indio_dev) { int ret, val; struct veml6030_data *data = iio_priv(indio_dev); struct i2c_client *client = data->client; ret = veml6030_als_shut_down(data); if (ret) { dev_err(&client->dev, "can't shutdown als %d\n", ret); return ret; } ret = regmap_write(data->regmap, VEML6030_REG_ALS_CONF, 0x1001); if (ret) { dev_err(&client->dev, "can't setup als configs %d\n", ret); return ret; } ret = regmap_update_bits(data->regmap, VEML6030_REG_ALS_PSM, VEML6030_PSM | VEML6030_PSM_EN, 0x03); if (ret) { dev_err(&client->dev, "can't setup default PSM %d\n", ret); return ret; } ret = regmap_write(data->regmap, VEML6030_REG_ALS_WH, 0xFFFF); if (ret) { dev_err(&client->dev, "can't setup high threshold %d\n", ret); return ret; } ret = regmap_write(data->regmap, VEML6030_REG_ALS_WL, 0x0000); if (ret) { dev_err(&client->dev, "can't setup low threshold %d\n", ret); return ret; } ret = veml6030_als_pwr_on(data); if (ret) { dev_err(&client->dev, "can't poweron als %d\n", ret); return ret; } /* Wait 4 ms to let processor & oscillator start correctly */ usleep_range(4000, 4002); /* Clear stale interrupt status bits if any during start */ ret = regmap_read(data->regmap, VEML6030_REG_ALS_INT, &val); if (ret < 0) { dev_err(&client->dev, "can't clear als interrupt status %d\n", ret); return ret; } /* Cache currently active measurement parameters */ data->cur_gain = 3; data->cur_resolution = 5376; data->cur_integration_time = 3; return ret; } static int veml6030_probe(struct i2c_client *client) { int ret; struct veml6030_data *data; struct iio_dev *indio_dev; struct regmap *regmap; if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { dev_err(&client->dev, "i2c adapter doesn't support plain i2c\n"); return -EOPNOTSUPP; } regmap = devm_regmap_init_i2c(client, &veml6030_regmap_config); if (IS_ERR(regmap)) { dev_err(&client->dev, "can't setup regmap\n"); return PTR_ERR(regmap); } 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; data->regmap = regmap; indio_dev->name = "veml6030"; indio_dev->channels = veml6030_channels; indio_dev->num_channels = ARRAY_SIZE(veml6030_channels); indio_dev->modes = INDIO_DIRECT_MODE; if (client->irq) { ret = devm_request_threaded_irq(&client->dev, client->irq, NULL, veml6030_event_handler, IRQF_TRIGGER_LOW | IRQF_ONESHOT, "veml6030", indio_dev); if (ret < 0) { dev_err(&client->dev, "irq %d request failed\n", client->irq); return ret; } indio_dev->info = &veml6030_info; } else { indio_dev->info = &veml6030_info_no_irq; } ret = veml6030_hw_init(indio_dev); if (ret < 0) return ret; ret = devm_add_action_or_reset(&client->dev, veml6030_als_shut_down_action, data); if (ret < 0) return ret; return devm_iio_device_register(&client->dev, indio_dev); } static int veml6030_runtime_suspend(struct device *dev) { int ret; struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); struct veml6030_data *data = iio_priv(indio_dev); ret = veml6030_als_shut_down(data); if (ret < 0) dev_err(&data->client->dev, "can't suspend als %d\n", ret); return ret; } static int veml6030_runtime_resume(struct device *dev) { int ret; struct iio_dev *indio_dev = i2c_get_clientdata(to_i2c_client(dev)); struct veml6030_data *data = iio_priv(indio_dev); ret = veml6030_als_pwr_on(data); if (ret < 0) dev_err(&data->client->dev, "can't resume als %d\n", ret); return ret; } static DEFINE_RUNTIME_DEV_PM_OPS(veml6030_pm_ops, veml6030_runtime_suspend, veml6030_runtime_resume, NULL); static const struct of_device_id veml6030_of_match[] = { { .compatible = "vishay,veml6030" }, { } }; MODULE_DEVICE_TABLE(of, veml6030_of_match); static const struct i2c_device_id veml6030_id[] = { { "veml6030", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, veml6030_id); static struct i2c_driver veml6030_driver = { .driver = { .name = "veml6030", .of_match_table = veml6030_of_match, .pm = pm_ptr(&veml6030_pm_ops), }, .probe = veml6030_probe, .id_table = veml6030_id, }; module_i2c_driver(veml6030_driver); MODULE_AUTHOR("Rishi Gupta "); MODULE_DESCRIPTION("VEML6030 Ambient Light Sensor"); MODULE_LICENSE("GPL v2");