--- /dev/null
+// 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");
projects / linux-2.6-microblaze.git / commitdiff