Commit b081b738 authored by Jeff LaBundy's avatar Jeff LaBundy Committed by Lee Jones
Browse files

iio: light: Add support for Azoteq IQS621/622 ambient light sensors 



This patch adds support for the Azoteq IQS621 and IQS622 ambient light
sensors, both of which can report a four-bit representation of ambient
light intensity.

The IQS621 can additionally report illuminace directly in units of lux,
while the IQS622 can report a four-bit representation of infrared light
intensity. Furthermore, the IQS622 can report a unitless measurement of
a target's proximity to the device.

Signed-off-by: default avatarJeff LaBundy <jeff@labundy.com>
Reviewed-by: default avatarJonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: default avatarLee Jones <lee.jones@linaro.org>
parent 8ba44710

drivers/iio/light/Kconfig

+10 −0
Original line number Diff line number Diff line
@@ -173,6 +173,16 @@ config GP2AP020A00F 
	  To compile this driver as a module, choose M here: the

	  module will be called gp2ap020a00f.



config IQS621_ALS

	tristate "Azoteq IQS621/622 ambient light sensors"

	depends on MFD_IQS62X || COMPILE_TEST

	help

	  Say Y here if you want to build support for the Azoteq IQS621

	  and IQS622 ambient light sensors.



	  To compile this driver as a module, choose M here: the module

	  will be called iqs621-als.



config SENSORS_ISL29018

	tristate "Intersil 29018 light and proximity sensor"

	depends on I2C

drivers/iio/light/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -21,6 +21,7 @@ obj-$(CONFIG_IIO_CROS_EC_LIGHT_PROX) += cros_ec_light_prox.o 
obj-$(CONFIG_GP2AP020A00F)	+= gp2ap020a00f.o

obj-$(CONFIG_HID_SENSOR_ALS)	+= hid-sensor-als.o

obj-$(CONFIG_HID_SENSOR_PROX)	+= hid-sensor-prox.o

obj-$(CONFIG_IQS621_ALS)	+= iqs621-als.o

obj-$(CONFIG_SENSORS_ISL29018)	+= isl29018.o

obj-$(CONFIG_SENSORS_ISL29028)	+= isl29028.o

obj-$(CONFIG_ISL29125)		+= isl29125.o

drivers/iio/light/iqs621-als.c

0 → 100644
+617 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0+

/*

 * Azoteq IQS621/622 Ambient Light Sensors

 *

 * Copyright (C) 2019 Jeff LaBundy <jeff@labundy.com>

 */



#include <linux/device.h>

#include <linux/iio/events.h>

#include <linux/iio/iio.h>

#include <linux/kernel.h>

#include <linux/mfd/iqs62x.h>

#include <linux/module.h>

#include <linux/mutex.h>

#include <linux/notifier.h>

#include <linux/platform_device.h>

#include <linux/regmap.h>



#define IQS621_ALS_FLAGS_LIGHT			BIT(7)

#define IQS621_ALS_FLAGS_RANGE			GENMASK(3, 0)



#define IQS621_ALS_UI_OUT			0x17



#define IQS621_ALS_THRESH_DARK			0x80

#define IQS621_ALS_THRESH_LIGHT			0x81



#define IQS622_IR_RANGE				0x15

#define IQS622_IR_FLAGS				0x16

#define IQS622_IR_FLAGS_TOUCH			BIT(1)

#define IQS622_IR_FLAGS_PROX			BIT(0)



#define IQS622_IR_UI_OUT			0x17



#define IQS622_IR_THRESH_PROX			0x91

#define IQS622_IR_THRESH_TOUCH			0x92



struct iqs621_als_private {

	struct iqs62x_core *iqs62x;

	struct notifier_block notifier;

	struct mutex lock;

	bool light_en;

	bool range_en;

	bool prox_en;

	u8 als_flags;

	u8 ir_flags_mask;

	u8 ir_flags;

	u8 thresh_light;

	u8 thresh_dark;

	u8 thresh_prox;

};



static int iqs621_als_init(struct iqs621_als_private *iqs621_als)

{

	struct iqs62x_core *iqs62x = iqs621_als->iqs62x;

	unsigned int event_mask = 0;

	int ret;



	switch (iqs621_als->ir_flags_mask) {

	case IQS622_IR_FLAGS_TOUCH:

		ret = regmap_write(iqs62x->regmap, IQS622_IR_THRESH_TOUCH,

				   iqs621_als->thresh_prox);

		break;



	case IQS622_IR_FLAGS_PROX:

		ret = regmap_write(iqs62x->regmap, IQS622_IR_THRESH_PROX,

				   iqs621_als->thresh_prox);

		break;



	default:

		ret = regmap_write(iqs62x->regmap, IQS621_ALS_THRESH_LIGHT,

				   iqs621_als->thresh_light);

		if (ret)

			return ret;



		ret = regmap_write(iqs62x->regmap, IQS621_ALS_THRESH_DARK,

				   iqs621_als->thresh_dark);

	}



	if (ret)

		return ret;



	if (iqs621_als->light_en || iqs621_als->range_en)

		event_mask |= iqs62x->dev_desc->als_mask;



	if (iqs621_als->prox_en)

		event_mask |= iqs62x->dev_desc->ir_mask;



	return regmap_update_bits(iqs62x->regmap, IQS620_GLBL_EVENT_MASK,

				  event_mask, 0);

}



static int iqs621_als_notifier(struct notifier_block *notifier,

			       unsigned long event_flags, void *context)

{

	struct iqs62x_event_data *event_data = context;

	struct iqs621_als_private *iqs621_als;

	struct iio_dev *indio_dev;

	bool light_new, light_old;

	bool prox_new, prox_old;

	u8 range_new, range_old;

	s64 timestamp;

	int ret;



	iqs621_als = container_of(notifier, struct iqs621_als_private,

				  notifier);

	indio_dev = iio_priv_to_dev(iqs621_als);

	timestamp = iio_get_time_ns(indio_dev);



	mutex_lock(&iqs621_als->lock);



	if (event_flags & BIT(IQS62X_EVENT_SYS_RESET)) {

		ret = iqs621_als_init(iqs621_als);

		if (ret) {

			dev_err(indio_dev->dev.parent,

				"Failed to re-initialize device: %d\n", ret);

			ret = NOTIFY_BAD;

		} else {

			ret = NOTIFY_OK;

		}



		goto err_mutex;

	}



	if (!iqs621_als->light_en && !iqs621_als->range_en &&

	    !iqs621_als->prox_en) {

		ret = NOTIFY_DONE;

		goto err_mutex;

	}



	/* IQS621 only */

	light_new = event_data->als_flags & IQS621_ALS_FLAGS_LIGHT;

	light_old = iqs621_als->als_flags & IQS621_ALS_FLAGS_LIGHT;



	if (iqs621_als->light_en && light_new && !light_old)

		iio_push_event(indio_dev,

			       IIO_UNMOD_EVENT_CODE(IIO_LIGHT, 0,

						    IIO_EV_TYPE_THRESH,

						    IIO_EV_DIR_RISING),

			       timestamp);

	else if (iqs621_als->light_en && !light_new && light_old)

		iio_push_event(indio_dev,

			       IIO_UNMOD_EVENT_CODE(IIO_LIGHT, 0,

						    IIO_EV_TYPE_THRESH,

						    IIO_EV_DIR_FALLING),

			       timestamp);



	/* IQS621 and IQS622 */

	range_new = event_data->als_flags & IQS621_ALS_FLAGS_RANGE;

	range_old = iqs621_als->als_flags & IQS621_ALS_FLAGS_RANGE;



	if (iqs621_als->range_en && (range_new > range_old))

		iio_push_event(indio_dev,

			       IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0,

						    IIO_EV_TYPE_CHANGE,

						    IIO_EV_DIR_RISING),

			       timestamp);

	else if (iqs621_als->range_en && (range_new < range_old))

		iio_push_event(indio_dev,

			       IIO_UNMOD_EVENT_CODE(IIO_INTENSITY, 0,

						    IIO_EV_TYPE_CHANGE,

						    IIO_EV_DIR_FALLING),

			       timestamp);



	/* IQS622 only */

	prox_new = event_data->ir_flags & iqs621_als->ir_flags_mask;

	prox_old = iqs621_als->ir_flags & iqs621_als->ir_flags_mask;



	if (iqs621_als->prox_en && prox_new && !prox_old)

		iio_push_event(indio_dev,

			       IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, 0,

						    IIO_EV_TYPE_THRESH,

						    IIO_EV_DIR_RISING),

			       timestamp);

	else if (iqs621_als->prox_en && !prox_new && prox_old)

		iio_push_event(indio_dev,

			       IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, 0,

						    IIO_EV_TYPE_THRESH,

						    IIO_EV_DIR_FALLING),

			       timestamp);



	iqs621_als->als_flags = event_data->als_flags;

	iqs621_als->ir_flags = event_data->ir_flags;

	ret = NOTIFY_OK;



err_mutex:

	mutex_unlock(&iqs621_als->lock);



	return ret;

}



static void iqs621_als_notifier_unregister(void *context)

{

	struct iqs621_als_private *iqs621_als = context;

	struct iio_dev *indio_dev = iio_priv_to_dev(iqs621_als);

	int ret;



	ret = blocking_notifier_chain_unregister(&iqs621_als->iqs62x->nh,

						 &iqs621_als->notifier);

	if (ret)

		dev_err(indio_dev->dev.parent,

			"Failed to unregister notifier: %d\n", ret);

}



static int iqs621_als_read_raw(struct iio_dev *indio_dev,

			       struct iio_chan_spec const *chan,

			       int *val, int *val2, long mask)

{

	struct iqs621_als_private *iqs621_als = iio_priv(indio_dev);

	struct iqs62x_core *iqs62x = iqs621_als->iqs62x;

	int ret;

	__le16 val_buf;



	switch (chan->type) {

	case IIO_INTENSITY:

		ret = regmap_read(iqs62x->regmap, chan->address, val);

		if (ret)

			return ret;



		*val &= IQS621_ALS_FLAGS_RANGE;

		return IIO_VAL_INT;



	case IIO_PROXIMITY:

	case IIO_LIGHT:

		ret = regmap_raw_read(iqs62x->regmap, chan->address, &val_buf,

				      sizeof(val_buf));

		if (ret)

			return ret;



		*val = le16_to_cpu(val_buf);

		return IIO_VAL_INT;



	default:

		return -EINVAL;

	}

}



static int iqs621_als_read_event_config(struct iio_dev *indio_dev,

					const struct iio_chan_spec *chan,

					enum iio_event_type type,

					enum iio_event_direction dir)

{

	struct iqs621_als_private *iqs621_als = iio_priv(indio_dev);

	int ret;



	mutex_lock(&iqs621_als->lock);



	switch (chan->type) {

	case IIO_LIGHT:

		ret = iqs621_als->light_en;

		break;



	case IIO_INTENSITY:

		ret = iqs621_als->range_en;

		break;



	case IIO_PROXIMITY:

		ret = iqs621_als->prox_en;

		break;



	default:

		ret = -EINVAL;

	}



	mutex_unlock(&iqs621_als->lock);



	return ret;

}



static int iqs621_als_write_event_config(struct iio_dev *indio_dev,

					 const struct iio_chan_spec *chan,

					 enum iio_event_type type,

					 enum iio_event_direction dir,

					 int state)

{

	struct iqs621_als_private *iqs621_als = iio_priv(indio_dev);

	struct iqs62x_core *iqs62x = iqs621_als->iqs62x;

	unsigned int val;

	int ret;



	mutex_lock(&iqs621_als->lock);



	ret = regmap_read(iqs62x->regmap, iqs62x->dev_desc->als_flags, &val);

	if (ret)

		goto err_mutex;

	iqs621_als->als_flags = val;



	switch (chan->type) {

	case IIO_LIGHT:

		ret = regmap_update_bits(iqs62x->regmap, IQS620_GLBL_EVENT_MASK,

					 iqs62x->dev_desc->als_mask,

					 iqs621_als->range_en || state ? 0 :

									 0xFF);

		if (!ret)

			iqs621_als->light_en = state;

		break;



	case IIO_INTENSITY:

		ret = regmap_update_bits(iqs62x->regmap, IQS620_GLBL_EVENT_MASK,

					 iqs62x->dev_desc->als_mask,

					 iqs621_als->light_en || state ? 0 :

									 0xFF);

		if (!ret)

			iqs621_als->range_en = state;

		break;



	case IIO_PROXIMITY:

		ret = regmap_read(iqs62x->regmap, IQS622_IR_FLAGS, &val);

		if (ret)

			goto err_mutex;

		iqs621_als->ir_flags = val;



		ret = regmap_update_bits(iqs62x->regmap, IQS620_GLBL_EVENT_MASK,

					 iqs62x->dev_desc->ir_mask,

					 state ? 0 : 0xFF);

		if (!ret)

			iqs621_als->prox_en = state;

		break;



	default:

		ret = -EINVAL;

	}



err_mutex:

	mutex_unlock(&iqs621_als->lock);



	return ret;

}



static int iqs621_als_read_event_value(struct iio_dev *indio_dev,

				       const struct iio_chan_spec *chan,

				       enum iio_event_type type,

				       enum iio_event_direction dir,

				       enum iio_event_info info,

				       int *val, int *val2)

{

	struct iqs621_als_private *iqs621_als = iio_priv(indio_dev);

	int ret = IIO_VAL_INT;



	mutex_lock(&iqs621_als->lock);



	switch (dir) {

	case IIO_EV_DIR_RISING:

		*val = iqs621_als->thresh_light * 16;

		break;



	case IIO_EV_DIR_FALLING:

		*val = iqs621_als->thresh_dark * 4;

		break;



	case IIO_EV_DIR_EITHER:

		if (iqs621_als->ir_flags_mask == IQS622_IR_FLAGS_TOUCH)

			*val = iqs621_als->thresh_prox * 4;

		else

			*val = iqs621_als->thresh_prox;

		break;



	default:

		ret = -EINVAL;

	}



	mutex_unlock(&iqs621_als->lock);



	return ret;

}



static int iqs621_als_write_event_value(struct iio_dev *indio_dev,

					const struct iio_chan_spec *chan,

					enum iio_event_type type,

					enum iio_event_direction dir,

					enum iio_event_info info,

					int val, int val2)

{

	struct iqs621_als_private *iqs621_als = iio_priv(indio_dev);

	struct iqs62x_core *iqs62x = iqs621_als->iqs62x;

	unsigned int thresh_reg, thresh_val;

	u8 ir_flags_mask, *thresh_cache;

	int ret = -EINVAL;



	mutex_lock(&iqs621_als->lock);



	switch (dir) {

	case IIO_EV_DIR_RISING:

		thresh_reg = IQS621_ALS_THRESH_LIGHT;

		thresh_val = val / 16;



		thresh_cache = &iqs621_als->thresh_light;

		ir_flags_mask = 0;

		break;



	case IIO_EV_DIR_FALLING:

		thresh_reg = IQS621_ALS_THRESH_DARK;

		thresh_val = val / 4;



		thresh_cache = &iqs621_als->thresh_dark;

		ir_flags_mask = 0;

		break;



	case IIO_EV_DIR_EITHER:

		/*

		 * The IQS622 supports two detection thresholds, both measured

		 * in the same arbitrary units reported by read_raw: proximity

		 * (0 through 255 in steps of 1), and touch (0 through 1020 in

		 * steps of 4).

		 *

		 * Based on the single detection threshold chosen by the user,

		 * select the hardware threshold that gives the best trade-off

		 * between range and resolution.

		 *

		 * By default, the close-range (but coarse) touch threshold is

		 * chosen during probe.

		 */

		switch (val) {

		case 0 ... 255:

			thresh_reg = IQS622_IR_THRESH_PROX;

			thresh_val = val;



			ir_flags_mask = IQS622_IR_FLAGS_PROX;

			break;



		case 256 ... 1020:

			thresh_reg = IQS622_IR_THRESH_TOUCH;

			thresh_val = val / 4;



			ir_flags_mask = IQS622_IR_FLAGS_TOUCH;

			break;



		default:

			goto err_mutex;

		}



		thresh_cache = &iqs621_als->thresh_prox;

		break;



	default:

		goto err_mutex;

	}



	if (thresh_val > 0xFF)

		goto err_mutex;



	ret = regmap_write(iqs62x->regmap, thresh_reg, thresh_val);

	if (ret)

		goto err_mutex;



	*thresh_cache = thresh_val;

	iqs621_als->ir_flags_mask = ir_flags_mask;



err_mutex:

	mutex_unlock(&iqs621_als->lock);



	return ret;

}



static const struct iio_info iqs621_als_info = {

	.read_raw = &iqs621_als_read_raw,

	.read_event_config = iqs621_als_read_event_config,

	.write_event_config = iqs621_als_write_event_config,

	.read_event_value = iqs621_als_read_event_value,

	.write_event_value = iqs621_als_write_event_value,

};



static const struct iio_event_spec iqs621_als_range_events[] = {

	{

		.type = IIO_EV_TYPE_CHANGE,

		.dir = IIO_EV_DIR_EITHER,

		.mask_separate = BIT(IIO_EV_INFO_ENABLE),

	},

};



static const struct iio_event_spec iqs621_als_light_events[] = {

	{

		.type = IIO_EV_TYPE_THRESH,

		.dir = IIO_EV_DIR_EITHER,

		.mask_separate = BIT(IIO_EV_INFO_ENABLE),

	},

	{

		.type = IIO_EV_TYPE_THRESH,

		.dir = IIO_EV_DIR_RISING,

		.mask_separate = BIT(IIO_EV_INFO_VALUE),

	},

	{

		.type = IIO_EV_TYPE_THRESH,

		.dir = IIO_EV_DIR_FALLING,

		.mask_separate = BIT(IIO_EV_INFO_VALUE),

	},

};



static const struct iio_chan_spec iqs621_als_channels[] = {

	{

		.type = IIO_INTENSITY,

		.address = IQS621_ALS_FLAGS,

		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),

		.event_spec = iqs621_als_range_events,

		.num_event_specs = ARRAY_SIZE(iqs621_als_range_events),

	},

	{

		.type = IIO_LIGHT,

		.address = IQS621_ALS_UI_OUT,

		.info_mask_separate = BIT(IIO_CHAN_INFO_PROCESSED),

		.event_spec = iqs621_als_light_events,

		.num_event_specs = ARRAY_SIZE(iqs621_als_light_events),

	},

};



static const struct iio_event_spec iqs622_als_prox_events[] = {

	{

		.type = IIO_EV_TYPE_THRESH,

		.dir = IIO_EV_DIR_EITHER,

		.mask_separate = BIT(IIO_EV_INFO_ENABLE) |

				 BIT(IIO_EV_INFO_VALUE),

	},

};



static const struct iio_chan_spec iqs622_als_channels[] = {

	{

		.type = IIO_INTENSITY,

		.channel2 = IIO_MOD_LIGHT_BOTH,

		.address = IQS622_ALS_FLAGS,

		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),

		.event_spec = iqs621_als_range_events,

		.num_event_specs = ARRAY_SIZE(iqs621_als_range_events),

		.modified = true,

	},

	{

		.type = IIO_INTENSITY,

		.channel2 = IIO_MOD_LIGHT_IR,

		.address = IQS622_IR_RANGE,

		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),

		.modified = true,

	},

	{

		.type = IIO_PROXIMITY,

		.address = IQS622_IR_UI_OUT,

		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),

		.event_spec = iqs622_als_prox_events,

		.num_event_specs = ARRAY_SIZE(iqs622_als_prox_events),

	},

};



static int iqs621_als_probe(struct platform_device *pdev)

{

	struct iqs62x_core *iqs62x = dev_get_drvdata(pdev->dev.parent);

	struct iqs621_als_private *iqs621_als;

	struct iio_dev *indio_dev;

	unsigned int val;

	int ret;



	indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*iqs621_als));

	if (!indio_dev)

		return -ENOMEM;



	iqs621_als = iio_priv(indio_dev);

	iqs621_als->iqs62x = iqs62x;



	if (iqs62x->dev_desc->prod_num == IQS622_PROD_NUM) {

		ret = regmap_read(iqs62x->regmap, IQS622_IR_THRESH_TOUCH,

				  &val);

		if (ret)

			return ret;

		iqs621_als->thresh_prox = val;

		iqs621_als->ir_flags_mask = IQS622_IR_FLAGS_TOUCH;



		indio_dev->channels = iqs622_als_channels;

		indio_dev->num_channels = ARRAY_SIZE(iqs622_als_channels);

	} else {

		ret = regmap_read(iqs62x->regmap, IQS621_ALS_THRESH_LIGHT,

				  &val);

		if (ret)

			return ret;

		iqs621_als->thresh_light = val;



		ret = regmap_read(iqs62x->regmap, IQS621_ALS_THRESH_DARK,

				  &val);

		if (ret)

			return ret;

		iqs621_als->thresh_dark = val;



		indio_dev->channels = iqs621_als_channels;

		indio_dev->num_channels = ARRAY_SIZE(iqs621_als_channels);

	}



	indio_dev->modes = INDIO_DIRECT_MODE;

	indio_dev->dev.parent = &pdev->dev;

	indio_dev->name = iqs62x->dev_desc->dev_name;

	indio_dev->info = &iqs621_als_info;



	mutex_init(&iqs621_als->lock);



	iqs621_als->notifier.notifier_call = iqs621_als_notifier;

	ret = blocking_notifier_chain_register(&iqs621_als->iqs62x->nh,

					       &iqs621_als->notifier);

	if (ret) {

		dev_err(&pdev->dev, "Failed to register notifier: %d\n", ret);

		return ret;

	}



	ret = devm_add_action_or_reset(&pdev->dev,

				       iqs621_als_notifier_unregister,

				       iqs621_als);

	if (ret)

		return ret;



	return devm_iio_device_register(&pdev->dev, indio_dev);

}



static struct platform_driver iqs621_als_platform_driver = {

	.driver = {

		.name = "iqs621-als",

	},

	.probe = iqs621_als_probe,

};

module_platform_driver(iqs621_als_platform_driver);



MODULE_AUTHOR("Jeff LaBundy <jeff@labundy.com>");

MODULE_DESCRIPTION("Azoteq IQS621/622 Ambient Light Sensors");

MODULE_LICENSE("GPL");

MODULE_ALIAS("platform:iqs621-als");

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