[PATCH v4 1/2] iio: light: driver for Vishay VEML6040

From: Arthur Becker via B4 Relay
Date: Tue Jun 04 2024 - 04:02:51 EST


From: Arthur Becker <arthur.becker@xxxxxxxxxx>

Implements driver for the Vishay VEML6040 rgbw light sensor.

Included functionality: setting the integration time and reading the raw
values for the four channels

Not yet implemented: setting the measurements to 'Manual Force Mode' (Auto
measurements off, and adding a measurement trigger)

Datasheet: https://www.vishay.com/docs/84276/veml6040.pdf
Signed-off-by: Arthur Becker <arthur.becker@xxxxxxxxxx>
---
V1 -> V2: Addressed review comments.
V2 -> V3: Addressed further review comments; Sending in patch thread
with dt-bindings.
V3 -> V4: Minor adjustments
---
drivers/iio/light/Kconfig | 11 ++
drivers/iio/light/Makefile | 1 +
drivers/iio/light/veml6040.c | 281 +++++++++++++++++++++++++++++++++++++++++++
3 files changed, 293 insertions(+)

diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index 9a587d403118..b68dcc1fbaca 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -666,6 +666,17 @@ config VEML6030
To compile this driver as a module, choose M here: the
module will be called veml6030.

+config VEML6040
+ tristate "VEML6040 RGBW light sensor"
+ select REGMAP_I2C
+ depends on I2C
+ help
+ Say Y here if you want to build a driver for the Vishay VEML6040
+ RGBW light sensor.
+
+ To compile this driver as a module, choose M here: the
+ module will be called veml6040.
+
config VEML6070
tristate "VEML6070 UV A light sensor"
depends on I2C
diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
index a30f906e91ba..1a071a8e9f8e 100644
--- a/drivers/iio/light/Makefile
+++ b/drivers/iio/light/Makefile
@@ -62,6 +62,7 @@ obj-$(CONFIG_US5182D) += us5182d.o
obj-$(CONFIG_VCNL4000) += vcnl4000.o
obj-$(CONFIG_VCNL4035) += vcnl4035.o
obj-$(CONFIG_VEML6030) += veml6030.o
+obj-$(CONFIG_VEML6040) += veml6040.o
obj-$(CONFIG_VEML6070) += veml6070.o
obj-$(CONFIG_VEML6075) += veml6075.o
obj-$(CONFIG_VL6180) += vl6180.o
diff --git a/drivers/iio/light/veml6040.c b/drivers/iio/light/veml6040.c
new file mode 100644
index 000000000000..216e271001a8
--- /dev/null
+++ b/drivers/iio/light/veml6040.c
@@ -0,0 +1,281 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Vishay VEML6040 RGBW light sensor driver
+ *
+ * Copyright (C) 2024 Sentec AG
+ * Author: Arthur Becker <arthur.becker@xxxxxxxxxx>
+ *
+ */
+
+#include <linux/bitfield.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+
+/* VEML6040 Configuration Registers
+ *
+ * SD: Shutdown
+ * AF: Auto / Force Mode (Auto Measurements On:0, Off:1)
+ * TR: Trigger Measurement (when AF Bit is set)
+ * IT: Integration Time
+ */
+#define VEML6040_CONF_REG 0x000
+#define VEML6040_CONF_SD_MSK BIT(0)
+#define VEML6040_CONF_AF_MSK BIT(1)
+#define VEML6040_CONF_TR_MSK BIT(2)
+#define VEML6040_CONF_IT_MSK GENMASK(6, 4)
+#define VEML6040_CONF_IT_40_MS 0
+#define VEML6040_CONF_IT_80_MS 1
+#define VEML6040_CONF_IT_160_MS 2
+#define VEML6040_CONF_IT_320_MS 3
+#define VEML6040_CONF_IT_640_MS 4
+#define VEML6040_CONF_IT_1280_MS 5
+
+/* VEML6040 Read Only Registers */
+#define VEML6040_REG_R 0x08
+#define VEML6040_REG_G 0x09
+#define VEML6040_REG_B 0x0A
+#define VEML6040_REG_W 0x0B
+
+static const int veml6040_it_ms[] = { 40, 80, 160, 320, 640, 1280 };
+
+enum veml6040_chan {
+ CH_RED,
+ CH_GREEN,
+ CH_BLUE,
+ CH_WHITE,
+};
+
+struct veml6040_data {
+ struct i2c_client *client;
+ struct regmap *regmap;
+};
+
+static const struct regmap_config veml6040_regmap_config = {
+ .name = "veml6040_regmap",
+ .reg_bits = 8,
+ .val_bits = 16,
+ .max_register = VEML6040_REG_W,
+ .val_format_endian = REGMAP_ENDIAN_LITTLE,
+};
+
+static int veml6040_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int *val,
+ int *val2, long mask)
+{
+ int ret, reg, it_index;
+ struct veml6040_data *data = iio_priv(indio_dev);
+ struct regmap *regmap = data->regmap;
+ struct device *dev = &data->client->dev;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = regmap_read(regmap, chan->address, &reg);
+ if (ret) {
+ dev_err(dev, "Data read failed: %d\n", ret);
+ return ret;
+ }
+ *val = reg;
+ return IIO_VAL_INT;
+
+ case IIO_CHAN_INFO_INT_TIME:
+ ret = regmap_read(regmap, VEML6040_CONF_REG, &reg);
+ if (ret) {
+ dev_err(dev, "Data read failed: %d\n", ret);
+ return ret;
+ }
+ it_index = FIELD_GET(VEML6040_CONF_IT_MSK, reg);
+ if (it_index >= ARRAY_SIZE(veml6040_it_ms)) {
+ dev_err(dev, "Invalid Integration Time Set");
+ return -EINVAL;
+ }
+ *val = veml6040_it_ms[it_index];
+ return IIO_VAL_INT;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static int veml6040_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan, int val,
+ int val2, long mask)
+{
+ struct veml6040_data *data = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_INT_TIME:
+ for (int i = 0; i < ARRAY_SIZE(veml6040_it_ms); i++) {
+ if (veml6040_it_ms[i] != val)
+ continue;
+
+ return regmap_update_bits(data->regmap,
+ VEML6040_CONF_REG,
+ VEML6040_CONF_IT_MSK,
+ FIELD_PREP(VEML6040_CONF_IT_MSK, i));
+ }
+ return -EINVAL;
+ default:
+ return -EINVAL;
+ }
+}
+
+static int veml6040_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:
+ *length = ARRAY_SIZE(veml6040_it_ms);
+ *vals = veml6040_it_ms;
+ *type = IIO_VAL_INT;
+ return IIO_AVAIL_LIST;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static const struct iio_info veml6040_info = {
+ .read_raw = veml6040_read_raw,
+ .write_raw = veml6040_write_raw,
+ .read_avail = veml6040_read_avail,
+};
+
+static const struct iio_chan_spec veml6040_channels[] = {
+ {
+ .type = IIO_INTENSITY,
+ .address = VEML6040_REG_R,
+ .channel = CH_RED,
+ .channel2 = IIO_MOD_LIGHT_RED,
+ .modified = 1,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_INT_TIME),
+ .info_mask_shared_by_type_available =
+ BIT(IIO_CHAN_INFO_INT_TIME),
+ },
+ {
+ .type = IIO_INTENSITY,
+ .address = VEML6040_REG_G,
+ .channel = CH_GREEN,
+ .channel2 = IIO_MOD_LIGHT_GREEN,
+ .modified = 1,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_INT_TIME),
+ .info_mask_shared_by_type_available =
+ BIT(IIO_CHAN_INFO_INT_TIME),
+ },
+ {
+ .type = IIO_INTENSITY,
+ .address = VEML6040_REG_B,
+ .channel = CH_BLUE,
+ .channel2 = IIO_MOD_LIGHT_BLUE,
+ .modified = 1,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_INT_TIME),
+ .info_mask_shared_by_type_available =
+ BIT(IIO_CHAN_INFO_INT_TIME),
+ },
+ {
+ .type = IIO_INTENSITY,
+ .address = VEML6040_REG_W,
+ .channel = CH_WHITE,
+ .channel2 = IIO_MOD_LIGHT_CLEAR,
+ .modified = 1,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_INT_TIME),
+ .info_mask_shared_by_type_available =
+ BIT(IIO_CHAN_INFO_INT_TIME),
+ }
+};
+
+static void veml6040_shutdown_action(void *data)
+{
+ struct veml6040_data *veml6040_data = data;
+
+ regmap_update_bits(veml6040_data->regmap, VEML6040_CONF_REG,
+ VEML6040_CONF_SD_MSK, VEML6040_CONF_SD_MSK);
+}
+
+static int veml6040_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct veml6040_data *data;
+ struct iio_dev *indio_dev;
+ struct regmap *regmap;
+ const int init_config =
+ FIELD_PREP(VEML6040_CONF_IT_MSK, VEML6040_CONF_IT_40_MS) |
+ FIELD_PREP(VEML6040_CONF_AF_MSK, 0) |
+ FIELD_PREP(VEML6040_CONF_SD_MSK, 0);
+ int ret;
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C))
+ return dev_err_probe(dev, -EOPNOTSUPP,
+ "I2C adapter doesn't support plain I2C\n");
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*data));
+ if (!indio_dev)
+ return dev_err_probe(dev, -ENOMEM,
+ "IIO device allocation failed\n");
+
+ regmap = devm_regmap_init_i2c(client, &veml6040_regmap_config);
+ if (IS_ERR(regmap))
+ return dev_err_probe(dev, PTR_ERR(regmap),
+ "Regmap setup failed\n");
+
+ data = iio_priv(indio_dev);
+ i2c_set_clientdata(client, indio_dev);
+ data->client = client;
+ data->regmap = regmap;
+
+ indio_dev->name = "veml6040";
+ indio_dev->info = &veml6040_info;
+ indio_dev->channels = veml6040_channels;
+ indio_dev->num_channels = ARRAY_SIZE(veml6040_channels);
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ ret = devm_regulator_get_enable(dev, "vdd");
+ if (ret)
+ return ret;
+
+ ret = regmap_write(regmap, VEML6040_CONF_REG, init_config);
+ if (ret)
+ return dev_err_probe(dev, ret,
+ "Could not set initial config\n");
+
+ ret = devm_add_action_or_reset(dev, veml6040_shutdown_action, data);
+ if (ret)
+ return ret;
+
+ return devm_iio_device_register(dev, indio_dev);
+}
+
+static const struct i2c_device_id veml6040_id_table[] = {
+ {"veml6040"},
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, veml6040_id_table);
+
+static const struct of_device_id veml6040_of_match[] = {
+ {.compatible = "vishay,veml6040"},
+ {}
+};
+MODULE_DEVICE_TABLE(of, veml6040_of_match);
+
+static struct i2c_driver veml6040_driver = {
+ .probe = veml6040_probe,
+ .id_table = veml6040_id_table,
+ .driver = {
+ .name = "veml6040",
+ .of_match_table = veml6040_of_match,
+ },
+};
+module_i2c_driver(veml6040_driver);
+
+MODULE_DESCRIPTION("veml6040 RGBW light sensor driver");
+MODULE_AUTHOR("Arthur Becker <arthur.becker@xxxxxxxxxx>");
+MODULE_LICENSE("GPL");

--
2.34.1