Re: [PATCH 2/2] iio: light: isl76682: Add ISL76682 driver

[Alexander Stein <alexander.stein@ew.tq-group.com>]

Hi Marek,

Am Donnerstag, 16. November 2023, 14:13:16 CET schrieb Marek Vasut:
> The ISL76682 is very basic ALS which only supports ALS or IR mode
> in four ranges, 1k/4k/16k/64k LUX. There is no IRQ support or any
> other fancy functionality.
> 
> Signed-off-by: Marek Vasut <marex@denx.de>
> ---
> Cc: Alexander Stein <alexander.stein@ew.tq-group.com>
> Cc: Andre Werner <andre.werner@systec-electronic.com>
> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Cc: Bjorn Helgaas <bhelgaas@google.com>
> Cc: Conor Dooley <conor+dt@kernel.org>
> Cc: Fabio Estevam <festevam@denx.de>
> Cc: Guenter Roeck <linux@roeck-us.net>
> Cc: Jonathan Cameron <jic23@kernel.org>
> Cc: Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
> Cc: Lars-Peter Clausen <lars@metafoo.de>
> Cc: Luca Ceresoli <luca.ceresoli@bootlin.com>
> Cc: Mark Brown <broonie@kernel.org>
> Cc: Matti Vaittinen <mazziesaccount@gmail.com>
> Cc: Naresh Solanki <naresh.solanki@9elements.com>
> Cc: Patrick Rudolph <patrick.rudolph@9elements.com>
> Cc: Rob Herring <robh+dt@kernel.org>
> Cc: Stefan Windfeldt-Prytz <stefan.windfeldt-prytz@axis.com>
> Cc: Vincent Tremblay <vincent@vtremblay.dev>
> Cc: devicetree@vger.kernel.org
> Cc: linux-iio@vger.kernel.org
> ---
> NOTE: I am not 100% sure about the SCALE handling, can you please
>       check esp. that one ? Thanks !
> ---
>  drivers/iio/light/Kconfig    |   8 +
>  drivers/iio/light/Makefile   |   1 +
>  drivers/iio/light/isl76682.c | 379 +++++++++++++++++++++++++++++++++++
>  3 files changed, 388 insertions(+)
>  create mode 100644 drivers/iio/light/isl76682.c
> 
> diff --git a/drivers/iio/light/Kconfig b/drivers/iio/light/Kconfig
> index 45edba797e4c7..124c45f509754 100644
> --- a/drivers/iio/light/Kconfig
> +++ b/drivers/iio/light/Kconfig
> @@ -252,6 +252,14 @@ config ISL29125
>  	  To compile this driver as a module, choose M here: the module will 
be
>  	  called isl29125.
> 
> +config ISL76682
> +	tristate "Intersil ISL76682 Light Sensor"
> +	depends on I2C
> +	select REGMAP_I2C
> +	help
> +	  Provides driver for the Intersil's ISL76682 device. This driver
> +	  supports the sysfs interface to get the ALS and IR intensity.
> +
>  config HID_SENSOR_ALS
>  	depends on HID_SENSOR_HUB
>  	select IIO_BUFFER
> diff --git a/drivers/iio/light/Makefile b/drivers/iio/light/Makefile
> index c0db4c4c36ec9..09fa585f3109f 100644
> --- a/drivers/iio/light/Makefile
> +++ b/drivers/iio/light/Makefile
> @@ -28,6 +28,7 @@ obj-$(CONFIG_IQS621_ALS)	+= iqs621-als.o
>  obj-$(CONFIG_SENSORS_ISL29018)	+= isl29018.o
>  obj-$(CONFIG_SENSORS_ISL29028)	+= isl29028.o
>  obj-$(CONFIG_ISL29125)		+= isl29125.o
> +obj-$(CONFIG_ISL76682)		+= isl76682.o
>  obj-$(CONFIG_JSA1212)		+= jsa1212.o
>  obj-$(CONFIG_SENSORS_LM3533)	+= lm3533-als.o
>  obj-$(CONFIG_LTR501)		+= ltr501.o
> diff --git a/drivers/iio/light/isl76682.c b/drivers/iio/light/isl76682.c
> new file mode 100644
> index 0000000000000..8b41a14bfe5be
> --- /dev/null
> +++ b/drivers/iio/light/isl76682.c
> @@ -0,0 +1,379 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * IIO driver for the light sensor ISL76682.
> + * ISL76682 is Ambient Light Sensor
> + *
> + * Copyright (c) 2023 Marek Vasut <marex@denx.de>
> + */
> +
> +#include <linux/delay.h>
> +#include <linux/err.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/mutex.h>
> +#include <linux/regmap.h>
> +
> +#include <linux/iio/iio.h>
> +#include <linux/iio/sysfs.h>
> +
> +#define ISL76682_REG_COMMAND			0x00
> +
> +#define ISL76682_COMMAND_EN			BIT(7)
> +#define ISL76682_COMMAND_MODE_CONTINUOUS	BIT(6)
> +#define ISL76682_COMMAND_LIGHT_IR		BIT(5)
> +
> +#define ISL76682_COMMAND_RANGE_LUX_1K		0
> +#define ISL76682_COMMAND_RANGE_LUX_4K		(1 << 0)
> +#define ISL76682_COMMAND_RANGE_LUX_16K		(2 << 0)
> +#define ISL76682_COMMAND_RANGE_LUX_64K		(3 << 0)
> +#define ISL76682_COMMAND_RANGE_LUX_MASK		GENMASK(1, 0)
> +
> +#define ISL76682_REG_ALSIR_L			0x01
> +
> +#define ISL76682_REG_ALSIR_U			0x02
> +
> +#define ISL76682_NUM_REGS			(ISL76682_REG_ALSIR_U + 1)
> +
> +#define ISL76682_CONV_TIME_MS			100
> +
> +#define ISL76682_ADC_MAX			0xffff
> +
> +enum isl76682_als_ir_mode {
> +	ISL76682_MODE_NONE = 0,
> +	ISL76682_MODE_ALS,
> +	ISL76682_MODE_IR,
> +};
> +
> +struct isl76682_chip {
> +	struct mutex			lock;
> +	struct regmap			*regmap;
> +	enum isl76682_als_ir_mode	als_ir_mode;
> +	int				lux_scale;
> +};
> +
> +static int isl76682_set_als_scale(struct isl76682_chip *chip, int
> lux_scale) +{
> +	int ret, val;
> +

How about
	if (chip->lux_scale == lux_scale)
		return 0;
similar to the short path in isl76682_set_als_ir_mode()?

best regards,
Alexander

> +	if (lux_scale == 1000)
> +		val = ISL76682_COMMAND_RANGE_LUX_1K;
> +	else if (lux_scale == 4000)
> +		val = ISL76682_COMMAND_RANGE_LUX_4K;
> +	else if (lux_scale == 16000)
> +		val = ISL76682_COMMAND_RANGE_LUX_16K;
> +	else if (lux_scale == 64000)
> +		val = ISL76682_COMMAND_RANGE_LUX_64K;
> +	else
> +		return -EINVAL;
> +
> +	ret = regmap_update_bits(chip->regmap, ISL76682_REG_COMMAND,
> +				 ISL76682_COMMAND_RANGE_LUX_MASK, 
val);
> +	if (ret < 0)
> +		return ret;
> +
> +	chip->lux_scale = lux_scale;
> +
> +	return 0;
> +}
> +
> +static int isl76682_set_als_ir_mode(struct isl76682_chip *chip,
> +				    enum isl76682_als_ir_mode mode)
> +{
> +	int ret;
> +
> +	if (chip->als_ir_mode == mode)
> +		return 0;
> +
> +	if (mode == ISL76682_MODE_NONE) {
> +		return regmap_clear_bits(chip->regmap, 
ISL76682_REG_COMMAND,
> +					 ISL76682_COMMAND_EN);
> +	}
> +
> +	ret = isl76682_set_als_scale(chip, chip->lux_scale);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (mode == ISL76682_MODE_ALS) {
> +		ret = regmap_clear_bits(chip->regmap, 
ISL76682_REG_COMMAND,
> +					ISL76682_COMMAND_LIGHT_IR);
> +	} else {
> +		ret = regmap_set_bits(chip->regmap, ISL76682_REG_COMMAND,
> +				      ISL76682_COMMAND_LIGHT_IR);
> +	}
> +	if (ret < 0)
> +		return ret;
> +
> +	/* Enable the ALS/IR */
> +	ret = regmap_set_bits(chip->regmap, ISL76682_REG_COMMAND,
> +			      ISL76682_COMMAND_EN |
> +			      ISL76682_COMMAND_MODE_CONTINUOUS);
> +	if (ret < 0)
> +		return ret;
> +
> +	/* Need to wait for conversion time if ALS/IR mode enabled */
> +	msleep(ISL76682_CONV_TIME_MS);
> +
> +	chip->als_ir_mode = mode;
> +
> +	return 0;
> +}
> +
> +static int isl76682_read_als_ir(struct isl76682_chip *chip, int *als_ir)
> +{
> +	unsigned int lsb, msb;
> +	int ret;
> +
> +	ret = regmap_read(chip->regmap, ISL76682_REG_ALSIR_L, &lsb);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = regmap_read(chip->regmap, ISL76682_REG_ALSIR_U, &msb);
> +	if (ret < 0)
> +		return ret;
> +
> +	*als_ir = (msb << 8) | lsb;
> +
> +	return 0;
> +}
> +
> +static int isl76682_als_get(struct isl76682_chip *chip, int *als_data)
> +{
> +	int als_ir_data;
> +	int ret;
> +
> +	ret = isl76682_set_als_ir_mode(chip, ISL76682_MODE_ALS);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = isl76682_read_als_ir(chip, &als_ir_data);
> +	if (ret < 0)
> +		return ret;
> +
> +	*als_data = als_ir_data;
> +
> +	return 0;
> +}
> +
> +static int isl76682_ir_get(struct isl76682_chip *chip, int *ir_data)
> +{
> +	int ret;
> +
> +	ret = isl76682_set_als_ir_mode(chip, ISL76682_MODE_IR);
> +	if (ret < 0)
> +		return ret;
> +
> +	return isl76682_read_als_ir(chip, ir_data);
> +}
> +
> +static int isl76682_write_raw(struct iio_dev *indio_dev,
> +			      struct iio_chan_spec const *chan,
> +			      int val, int val2, long mask)
> +{
> +	struct isl76682_chip *chip = iio_priv(indio_dev);
> +	int ret;
> +
> +	if (chan->type != IIO_LIGHT)
> +		return -EINVAL;
> +
> +	if (mask != IIO_CHAN_INFO_SCALE)
> +		return -EINVAL;
> +
> +	mutex_lock(&chip->lock);
> +	ret = isl76682_set_als_scale(chip, val);
> +	mutex_unlock(&chip->lock);
> +
> +	return ret;
> +}
> +
> +static int isl76682_read_raw(struct iio_dev *indio_dev,
> +			     struct iio_chan_spec const *chan,
> +			     int *val, int *val2, long mask)
> +{
> +	struct isl76682_chip *chip = iio_priv(indio_dev);
> +	int ret;
> +
> +	mutex_lock(&chip->lock);
> +
> +	ret = -EINVAL;
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		switch (chan->type) {
> +		case IIO_LIGHT:
> +			ret = isl76682_als_get(chip, val);
> +			break;
> +		case IIO_INTENSITY:
> +			ret = isl76682_ir_get(chip, val);
> +			break;
> +		default:
> +			break;
> +		}
> +
> +		if (ret < 0)
> +			break;
> +
> +		ret = IIO_VAL_INT;
> +		break;
> +	case IIO_CHAN_INFO_SCALE:
> +		if (chan->type != IIO_LIGHT)
> +			break;
> +		*val = chip->lux_scale;
> +		*val2 = ISL76682_ADC_MAX;
> +		ret = IIO_VAL_FRACTIONAL;
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	mutex_unlock(&chip->lock);
> +
> +	return ret;
> +}
> +
> +static IIO_CONST_ATTR(in_illuminance_scale_available, "1000 4000 16000
> 64000"); +
> +#define ISL76682_CONST_ATTR(name) (&iio_const_attr_##name.dev_attr.attr)
> +static struct attribute *isl76682_attributes[] = {
> +	ISL76682_CONST_ATTR(in_illuminance_scale_available),
> +	NULL,
> +};
> +
> +static const struct attribute_group isl29108_group = {
> +	.attrs = isl76682_attributes,
> +};
> +
> +static const struct iio_chan_spec isl76682_channels[] = {
> +	{
> +		.type = IIO_LIGHT,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
> +				      BIT(IIO_CHAN_INFO_SCALE),
> +	}, {
> +		.type = IIO_INTENSITY,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> +	}
> +};
> +
> +static const struct iio_info isl76682_info = {
> +	.attrs		= &isl29108_group,
> +	.read_raw	= isl76682_read_raw,
> +	.write_raw	= isl76682_write_raw,
> +};
> +
> +static int isl76682_clear_configure_reg(struct isl76682_chip *chip)
> +{
> +	struct device *dev = regmap_get_device(chip->regmap);
> +	int ret;
> +
> +	ret = regmap_write(chip->regmap, ISL76682_REG_COMMAND, 0x0);
> +	if (ret < 0)
> +		dev_err(dev, "%s(): Error %d clearing the CONFIGURE 
register\n",
> +			__func__, ret);
> +
> +	chip->als_ir_mode = ISL76682_MODE_NONE;
> +
> +	return ret;
> +}
> +
> +static bool isl76682_is_volatile_reg(struct device *dev, unsigned int reg)
> +{
> +	switch (reg) {
> +	case ISL76682_REG_ALSIR_L:
> +	case ISL76682_REG_ALSIR_U:
> +		return true;
> +	default:
> +		return false;
> +	}
> +}
> +
> +static const struct regmap_config isl76682_regmap_config = {
> +	.reg_bits = 8,
> +	.val_bits = 8,
> +	.volatile_reg = isl76682_is_volatile_reg,
> +	.max_register = ISL76682_NUM_REGS - 1,
> +	.num_reg_defaults_raw = ISL76682_NUM_REGS,
> +	.cache_type = REGCACHE_FLAT,
> +};
> +
> +static int isl76682_probe(struct i2c_client *client)
> +{
> +	const struct i2c_device_id *id = i2c_client_get_device_id(client);
> +	struct isl76682_chip *chip;
> +	struct iio_dev *indio_dev;
> +	int ret;
> +
> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*chip));
> +	if (!indio_dev)
> +		return -ENOMEM;
> +
> +	chip = iio_priv(indio_dev);
> +
> +	i2c_set_clientdata(client, indio_dev);
> +	mutex_init(&chip->lock);
> +
> +	chip->regmap = devm_regmap_init_i2c(client, 
&isl76682_regmap_config);
> +	if (IS_ERR(chip->regmap)) {
> +		ret = PTR_ERR(chip->regmap);
> +		dev_err(&client->dev, "%s: Error %d initializing 
regmap\n",
> +			__func__, ret);
> +		return ret;
> +	}
> +
> +	chip->lux_scale = 1000;
> +
> +	ret = isl76682_clear_configure_reg(chip);
> +	if (ret < 0)
> +		return ret;
> +
> +	indio_dev->info = &isl76682_info;
> +	indio_dev->channels = isl76682_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(isl76682_channels);
> +	indio_dev->name = id->name;
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +
> +	ret = iio_device_register(indio_dev);
> +	if (ret < 0) {
> +		dev_err(&client->dev,
> +			"%s(): iio registration failed with error %d\n",
> +			__func__, ret);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static void isl76682_remove(struct i2c_client *client)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +	struct isl76682_chip *chip = iio_priv(indio_dev);
> +
> +	iio_device_unregister(indio_dev);
> +
> +	isl76682_clear_configure_reg(chip);
> +}
> +
> +static const struct i2c_device_id isl76682_id[] = {
> +	{"isl76682", 0},
> +	{}
> +};
> +MODULE_DEVICE_TABLE(i2c, isl76682_id);
> +
> +static const struct of_device_id isl76682_of_match[] = {
> +	{ .compatible = "isil,isl76682", },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, isl76682_of_match);
> +
> +static struct i2c_driver isl76682_driver = {
> +	.driver  = {
> +		.name = "isl76682",
> +		.of_match_table = isl76682_of_match,
> +	},
> +	.probe = isl76682_probe,
> +	.remove = isl76682_remove,
> +	.id_table = isl76682_id,
> +};
> +
> +module_i2c_driver(isl76682_driver);
> +
> +MODULE_DESCRIPTION("ISL76682 Ambient Light Sensor driver");
> +MODULE_LICENSE("GPL v2");
> +MODULE_AUTHOR("Marek Vasut <marex@denx.de>");


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