* [PATCH 2/2] iio: light: add support for veml3235
2024-10-16 21:39 [PATCH 0/2] iio: light: add support for veml3235 Javier Carrasco
2024-10-16 21:39 ` [PATCH 1/2] dt-bindings: iio: light: veml6030: add veml3235 Javier Carrasco
@ 2024-10-16 21:39 ` Javier Carrasco
2024-10-19 14:31 ` Jonathan Cameron
1 sibling, 1 reply; 5+ messages in thread
From: Javier Carrasco @ 2024-10-16 21:39 UTC (permalink / raw)
To: Jonathan Cameron, Lars-Peter Clausen, Rob Herring,
Krzysztof Kozlowski, Conor Dooley, Rishi Gupta
Cc: linux-iio, devicetree, linux-kernel, Javier Carrasco
The Vishay veml3235 is a low-power ambient light sensor with I2C
interface. It provides a minimum detectable intensity of
0.0021 lx/cnt, configurable integration time and gain, and an additional
white channel to distinguish between different light sources.
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
---
MAINTAINERS | 6 +
drivers/iio/light/Kconfig | 11 +
drivers/iio/light/Makefile | 1 +
drivers/iio/light/veml3235.c | 534 +++++++++++++++++++++++++++++++++++++++++++
4 files changed, 552 insertions(+)
diff --git a/MAINTAINERS b/MAINTAINERS
index 5ed860685cd1..ae7cb38fb64e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -24798,6 +24798,12 @@ S: Maintained
F: drivers/input/serio/userio.c
F: include/uapi/linux/userio.h
+VISHAY VEML3235 AMBIENT LIGHT SENSOR DRIVER
+M: Javier Carrasco <javier.carrasco.cruz@gmail.com>
+S: Maintained
+F: Documentation/devicetree/bindings/iio/light/vishay,veml6030.yaml
+F: drivers/iio/light/veml3235.c
+
VISHAY VEML6030 AMBIENT LIGHT SENSOR DRIVER
M: Javier Carrasco <javier.carrasco.cruz@gmail.com>
S: Maintained
diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
index c38b3c603ab4..c6b7ed0c61a1 100644
--- a/drivers/iio/light/Kconfig
+++ b/drivers/iio/light/Kconfig
@@ -670,6 +670,17 @@ config VCNL4035
To compile this driver as a module, choose M here: the
module will be called vcnl4035.
+config VEML3235
+ tristate "VEML3235 ambient light sensor"
+ select REGMAP_I2C
+ depends on I2C
+ help
+ Say Y here if you want to build a driver for the Vishay VEML3235
+ ambient light sensor.
+
+ To compile this driver as a module, choose M here: the
+ module will be called veml3235.
+
config VEML6030
tristate "VEML6030 and VEML6035 ambient light sensors"
select REGMAP_I2C
diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
index 321010fc0b93..f14a37442712 100644
--- a/drivers/iio/light/Makefile
+++ b/drivers/iio/light/Makefile
@@ -62,6 +62,7 @@ obj-$(CONFIG_TSL4531) += tsl4531.o
obj-$(CONFIG_US5182D) += us5182d.o
obj-$(CONFIG_VCNL4000) += vcnl4000.o
obj-$(CONFIG_VCNL4035) += vcnl4035.o
+obj-$(CONFIG_VEML3235) += veml3235.o
obj-$(CONFIG_VEML6030) += veml6030.o
obj-$(CONFIG_VEML6040) += veml6040.o
obj-$(CONFIG_VEML6070) += veml6070.o
diff --git a/drivers/iio/light/veml3235.c b/drivers/iio/light/veml3235.c
new file mode 100644
index 000000000000..9bda42379456
--- /dev/null
+++ b/drivers/iio/light/veml3235.c
@@ -0,0 +1,534 @@
+// 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_SD BIT(0)
+#define VEML3235_SD0 BIT(8)
+
+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;
+ int gain;
+ int it;
+ int resolution;
+};
+
+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_SD |
+ VEML3235_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_SD |
+ VEML3235_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) |
+ BIT(IIO_CHAN_INFO_PROCESSED),
+ .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, it_idx;
+
+ if (val)
+ return -EINVAL;
+
+ switch (val2) {
+ case 50000:
+ new_it = 0x00;
+ it_idx = 4;
+ break;
+ case 100000:
+ new_it = 0x01;
+ it_idx = 3;
+ break;
+ case 200000:
+ new_it = 0x02;
+ it_idx = 2;
+ break;
+ case 400000:
+ new_it = 0x03;
+ it_idx = 1;
+ break;
+ case 800000:
+ new_it = 0x04;
+ it_idx = 0;
+ 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;
+ }
+
+ if (data->it < it_idx)
+ data->resolution <<= it_idx - data->it;
+ else if (data->it > it_idx)
+ data->resolution >>= data->it - it_idx;
+
+ data->it = it_idx;
+
+ 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, gain_idx;
+
+ if (val == 1 && val2 == 0) {
+ new_gain = 0x00;
+ gain_idx = 3;
+ } else if (val == 2 && val2 == 0) {
+ new_gain = 0x01;
+ gain_idx = 2;
+ } else if (val == 4 && val2 == 0) {
+ new_gain = 0x03;
+ gain_idx = 1;
+ } else if (val == 8 && val2 == 0) {
+ new_gain = 0x07;
+ gain_idx = 0;
+ } else {
+ 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;
+ }
+
+ if (data->gain < gain_idx)
+ data->resolution <<= gain_idx - data->gain;
+ else if (data->gain > gain_idx)
+ data->resolution >>= data->gain - gain_idx;
+
+ data->gain = gain_idx;
+
+ 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:
+ case IIO_CHAN_INFO_PROCESSED:
+ switch (chan->type) {
+ case IIO_LIGHT:
+ ret = regmap_read(regmap, VEML3235_REG_ALS_DATA, ®);
+ if (ret < 0)
+ return ret;
+
+ if (mask == IIO_CHAN_INFO_PROCESSED) {
+ *val = (reg * data->resolution) / 100000;
+ *val2 = (reg * data->resolution) % 100000 * 10;
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+ *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;
+ }
+
+ 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 int veml3235_read_id(struct veml3235_data *data)
+{
+ int ret, reg;
+
+ ret = regmap_field_read(data->rf.id, ®);
+ if (ret)
+ return dev_err_probe(data->dev, ret, "failed to read ID\n");
+
+ if (reg != 0x35)
+ return dev_err_probe(data->dev, -ENODEV, "Unknown ID %d\n", reg);
+
+ return 0;
+}
+
+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 = regmap_write(data->regmap, VEML3235_REG_CONF, 0x1001);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to set configuration\n");
+
+ /*
+ * Set gain to 1, integration time to 100 ms, and the resulting
+ * resolution in (lux/cnt * 100000) according to the typical value
+ * from the datasheet.
+ */
+ 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");
+
+ data->gain = 3;
+ data->it = 3;
+ data->resolution = 13632;
+
+ 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;
+
+ ret = veml3235_read_id(data);
+ if (ret < 0)
+ return ret;
+
+ 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");
--
2.43.0
^ permalink raw reply related [flat|nested] 5+ messages in thread