[PATCH v4 0/2] Add driver for Vishay VEML6040

[PATCH v4 0/2] Add driver for Vishay VEML6040

[Arthur Becker via B4 Relay]

The driver allows to turn the module on/off, set the integration time
(in MS) for the sensors, and read the raw measurements of the Red,
Green, Blue and White sensors.

Thank you Jonathan, Krzysztof, Conor and Rob for your comments on the
driver, dt-bindings and my workflow!

To: Jonathan Cameron <jic23@kernel.org>
To: Lars-Peter Clausen <lars@metafoo.de>
To: Rob Herring <robh@kernel.org>
To: Krzysztof Kozlowski <krzk+dt@kernel.org>
To: Conor Dooley <conor+dt@kernel.org>
To: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Cc: linux-kernel@vger.kernel.org
Cc: linux-iio@vger.kernel.org
Cc: devicetree@vger.kernel.org
Signed-off-by: Arthur Becker <arthur.becker@sentec.com>

Changes in v4:
- Minor adjustments to the driver
- Merged dt-bindings with veml6075
- Link to v3: https://lore.kernel.org/r/20240527-veml6040-v3-0-6f3bbfd42960@sentec.com

---
Arthur Becker (2):
      iio: light: driver for Vishay VEML6040
      dt-bindings: iio: light: add VEML6040 RGBW-LS bindings

 .../bindings/iio/light/vishay,veml6075.yaml        |   9 +-
 drivers/iio/light/Kconfig                          |  11 +
 drivers/iio/light/Makefile                         |   1 +
 drivers/iio/light/veml6040.c                       | 281 +++++++++++++++++++++
 4 files changed, 300 insertions(+), 2 deletions(-)
---
base-commit: 1613e604df0cd359cf2a7fbd9be7a0bcfacfabd0
change-id: 20240527-veml6040-0314fc054337

Best regards,
-- 
Arthur Becker <arthur.becker@sentec.com>

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

[Arthur Becker via B4 Relay]

From: Arthur Becker <arthur.becker@sentec.com>

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@sentec.com>
---
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@sentec.com>
+ *
+ */
+
+#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@sentec.com>");
+MODULE_LICENSE("GPL");

-- 
2.34.1

[PATCH v4 2/2] dt-bindings: iio: light: add VEML6040 RGBW-LS bindings

[Arthur Becker via B4 Relay]

From: Arthur Becker <arthur.becker@sentec.com>

Device tree bindings for the vishay VEML6040 RGBW light sensor iio
driver

Signed-off-by: Arthur Becker <arthur.becker@sentec.com>
---
V1 -> V3: Addressed review comments (v1 of the dt-bindings was sent
along with v2 of the driver but not in a set)
V3 -> V4: Combined dt-binding with veml6075 as they are basically the
same
---
 Documentation/devicetree/bindings/iio/light/vishay,veml6075.yaml | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/Documentation/devicetree/bindings/iio/light/vishay,veml6075.yaml b/Documentation/devicetree/bindings/iio/light/vishay,veml6075.yaml
index 91c318746bf3..ecf2339e02f6 100644
--- a/Documentation/devicetree/bindings/iio/light/vishay,veml6075.yaml
+++ b/Documentation/devicetree/bindings/iio/light/vishay,veml6075.yaml
@@ -4,14 +4,19 @@
 $id: http://devicetree.org/schemas/iio/light/vishay,veml6075.yaml#
 $schema: http://devicetree.org/meta-schemas/core.yaml#
 
-title: Vishay VEML6075 UVA and UVB sensor
+title: Vishay VEML6075 UVA/B and VEML6040 RGBW sensors
 
 maintainers:
   - Javier Carrasco <javier.carrasco.cruz@gmail.com>
 
+description:
+  VEML6040 datasheet at https://www.vishay.com/docs/84276/veml6040.pdf
+
 properties:
   compatible:
-    const: vishay,veml6075
+    enum:
+      - vishay,veml6040
+      - vishay,veml6075
 
   reg:
     maxItems: 1

-- 
2.34.1

Re: [PATCH v4 2/2] dt-bindings: iio: light: add VEML6040 RGBW-LS bindings

[Krzysztof Kozlowski]

On 04/06/2024 10:01, Arthur Becker via B4 Relay wrote:
> From: Arthur Becker <arthur.becker@sentec.com>
> 
> Device tree bindings for the vishay VEML6040 RGBW light sensor iio
> driver
> 
> Signed-off-by: Arthur Becker <arthur.becker@sentec.com>
> ---

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>

If there is any resend:
A nit, subject: drop second/last, redundant "bindings". The
"dt-bindings" prefix is already stating that these are bindings.
See also:
https://elixir.bootlin.com/linux/v6.7-rc8/source/Documentation/devicetree/bindings/submitting-patches.rst#L18

Best regards,
Krzysztof

Re: [EXTERNAL]Re: [PATCH v4 2/2] dt-bindings: iio: light: add VEML6040 RGBW-LS bindings

[Arthur Becker]

From: Krzysztof Kozlowski <krzk@kernel.org>
Sent: 04 June 2024 10:45
To: Arthur Becker; Jonathan Cameron; Lars-Peter Clausen; Rob Herring; Krzysztof Kozlowski; Conor Dooley; Javier Carrasco
Cc: linux-kernel@vger.kernel.org; linux-iio@vger.kernel.org; devicetree@vger.kernel.org
Subject: [EXTERNAL]Re: [PATCH v4 2/2] dt-bindings: iio: light: add VEML6040 RGBW-LS bindings

> On 04/06/2024 10:01, Arthur Becker via B4 Relay wrote:
> > From: Arthur Becker <arthur.becker@sentec.com>
> >
> > Device tree bindings for the vishay VEML6040 RGBW light sensor iio
> > driver
> >
> > Signed-off-by: Arthur Becker <arthur.becker@sentec.com>
> > ---
>
> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>
> If there is any resend:
> A nit, subject: drop second/last, redundant "bindings". The
> "dt-bindings" prefix is already stating that these are bindings.
> See also:
> https://elixir.bootlin.com/linux/v6.7-rc8/source/Documentation/devicetree/bindings/submitting-patches.rst#L18
>
> Best regards,
> Krzysztof

Oups! I had read that part of the documentation but forgot about it...
I'll think about it next time.

Thanks for the review!

Kind Regards
Arthur

Re: [EXTERNAL]Re: [PATCH v4 2/2] dt-bindings: iio: light: add VEML6040 RGBW-LS bindings

[Krzysztof Kozlowski]

On 04/06/2024 10:59, Arthur Becker wrote:
>> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>>
>> If there is any resend:
>> A nit, subject: drop second/last, redundant "bindings". The
>> "dt-bindings" prefix is already stating that these are bindings.
>> See also:
>> https://elixir.bootlin.com/linux/v6.7-rc8/source/Documentation/devicetree/bindings/submitting-patches.rst#L18
>>
>> Best regards,
>> Krzysztof
> 
> Oups! I had read that part of the documentation but forgot about it...
> I'll think about it next time.
> 

It's fine, no worries.

Best regards,
Krzysztof

Re: [EXTERNAL]Re: [PATCH v4 2/2] dt-bindings: iio: light: add VEML6040 RGBW-LS bindings

[Jonathan Cameron]

On Tue, 4 Jun 2024 11:05:43 +0200
Krzysztof Kozlowski <krzk@kernel.org> wrote:

> On 04/06/2024 10:59, Arthur Becker wrote:
> >> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
> >>
> >> If there is any resend:
> >> A nit, subject: drop second/last, redundant "bindings". The
> >> "dt-bindings" prefix is already stating that these are bindings.
> >> See also:
> >> https://elixir.bootlin.com/linux/v6.7-rc8/source/Documentation/devicetree/bindings/submitting-patches.rst#L18
> >>
> >> Best regards,
> >> Krzysztof  
> > 
> > Oups! I had read that part of the documentation but forgot about it...
> > I'll think about it next time.
> >   
> 
> It's fine, no worries.
> 
> Best regards,
> Krzysztof
> 
I dropped the extra word whilst applying.

Applied to the togreg branch of iio.git and pushed out as testing for 0-day
to take a look at it.

Thanks,

Jonathan