drivers/iio/light/cm3605.c - third_party/linux - Git at Google

 /*
  * CM3605 Ambient Light and Proximity Sensor
  *
  * Copyright (C) 2016 Linaro Ltd.
  * Author: Linus Walleij <linus.walleij@linaro.org>
  *
  * This hardware was found in the very first Nexus One handset from Google/HTC
  * and an early endavour into mobile light and proximity sensors.
  */

 #include <linux/module.h>
 #include <linux/iio/iio.h>
 #include <linux/iio/sysfs.h>
 #include <linux/iio/events.h>
 #include <linux/iio/consumer.h> /* To get our ADC channel */
 #include <linux/iio/types.h> /* To deal with our ADC channel */
 #include <linux/init.h>
 #include <linux/leds.h>
 #include <linux/platform_device.h>
 #include <linux/of.h>
 #include <linux/regulator/consumer.h>
 #include <linux/gpio/consumer.h>
 #include <linux/interrupt.h>
 #include <linux/math64.h>
 #include <linux/pm.h>

 #define CM3605_PROX_CHANNEL 0
 #define CM3605_ALS_CHANNEL 1
 #define CM3605_AOUT_TYP_MAX_MV 1550
 /* It should not go above 1.650V according to the data sheet */
 #define CM3605_AOUT_MAX_MV 1650

 /**
  * struct cm3605 - CM3605 state
  * @dev: pointer to parent device
  * @vdd: regulator controlling VDD
  * @aset: sleep enable GPIO, high = sleep
  * @aout: IIO ADC channel to convert the AOUT signal
  * @als_max: maximum LUX detection (depends on RSET)
  * @dir: proximity direction: start as FALLING
  * @led: trigger for the infrared LED used by the proximity sensor
  */
 struct cm3605 {
 	struct device *dev;
 	struct regulator *vdd;
 	struct gpio_desc *aset;
 	struct iio_channel *aout;
 	s32 als_max;
 	enum iio_event_direction dir;
 	struct led_trigger *led;
 };

 static irqreturn_t cm3605_prox_irq(int irq, void *d)
 {
 	struct iio_dev *indio_dev = d;
 	struct cm3605 *cm3605 = iio_priv(indio_dev);
 	u64 ev;

 	ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, CM3605_PROX_CHANNEL,
 				  IIO_EV_TYPE_THRESH, cm3605->dir);
 	iio_push_event(indio_dev, ev, iio_get_time_ns(indio_dev));

 	/* Invert the edge for each event */
 	if (cm3605->dir == IIO_EV_DIR_RISING)
 		cm3605->dir = IIO_EV_DIR_FALLING;
 	else
 		cm3605->dir = IIO_EV_DIR_RISING;

 	return IRQ_HANDLED;
 }

 static int cm3605_get_lux(struct cm3605 *cm3605)
 {
 	int ret, res;
 	s64 lux;

 	ret = iio_read_channel_processed(cm3605->aout, &res);
 	if (ret < 0)
 		return ret;

 	dev_dbg(cm3605->dev, "read %d mV from ADC\n", res);

 	/*
 	 * AOUT has an offset of ~30mV then linear at dark
 	 * then goes from 2.54 up to 650 LUX yielding 1.55V
 	 * (1550 mV) so scale the returned value to this interval
 	 * using simple linear interpolation.
 	 */
 	if (res < 30)
 		return 0;
 	if (res > CM3605_AOUT_MAX_MV)
 		dev_err(cm3605->dev, "device out of range\n");

 	/* Remove bias */
 	lux = res - 30;

 	/* Linear interpolation between 0 and ALS typ max */
 	lux *= cm3605->als_max;
 	lux = div64_s64(lux, CM3605_AOUT_TYP_MAX_MV);

 	return lux;
 }

 static int cm3605_read_raw(struct iio_dev *indio_dev,
 			   struct iio_chan_spec const *chan,
 			   int *val, int *val2, long mask)
 {
 	struct cm3605 *cm3605 = iio_priv(indio_dev);
 	int ret;

 	switch (mask) {
 	case IIO_CHAN_INFO_RAW:
 		switch (chan->type) {
 		case IIO_LIGHT:
 			ret = cm3605_get_lux(cm3605);
 			if (ret < 0)
 				return ret;
 			*val = ret;
 			return IIO_VAL_INT;
 		default:
 			return -EINVAL;
 		}
 	default:
 		return -EINVAL;
 	}
 }

 static const struct iio_info cm3605_info = {
 	.read_raw = cm3605_read_raw,
 };

 static const struct iio_event_spec cm3605_events[] = {
 	{
 		.type = IIO_EV_TYPE_THRESH,
 		.dir = IIO_EV_DIR_EITHER,
 		.mask_separate = BIT(IIO_EV_INFO_ENABLE),
 	},
 };

 static const struct iio_chan_spec cm3605_channels[] = {
 	{
 		.type = IIO_PROXIMITY,
 		.event_spec = cm3605_events,
 		.num_event_specs = ARRAY_SIZE(cm3605_events),
 	},
 	{
 		.type = IIO_LIGHT,
 		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
 		.channel = CM3605_ALS_CHANNEL,
 	},
 };

 static int cm3605_probe(struct platform_device *pdev)
 {
 	struct cm3605 *cm3605;
 	struct iio_dev *indio_dev;
 	struct device *dev = &pdev->dev;
 	struct device_node *np = dev->of_node;
 	enum iio_chan_type ch_type;
 	u32 rset;
 	int ret;

 	indio_dev = devm_iio_device_alloc(dev, sizeof(*cm3605));
 	if (!indio_dev)
 		return -ENOMEM;
 	platform_set_drvdata(pdev, indio_dev);

 	cm3605 = iio_priv(indio_dev);
 	cm3605->dev = dev;
 	cm3605->dir = IIO_EV_DIR_FALLING;

 	ret = of_property_read_u32(np, "capella,aset-resistance-ohms", &rset);
 	if (ret) {
 		dev_info(dev, "no RSET specified, assuming 100K\n");
 		rset = 100000;
 	}
 	switch (rset) {
 	case 50000:
 		cm3605->als_max = 650;
 		break;
 	case 100000:
 		cm3605->als_max = 300;
 		break;
 	case 300000:
 		cm3605->als_max = 100;
 		break;
 	case 600000:
 		cm3605->als_max = 50;
 		break;
 	default:
 		dev_info(dev, "non-standard resistance\n");
 		return -EINVAL;
 	}

 	cm3605->aout = devm_iio_channel_get(dev, "aout");
 	if (IS_ERR(cm3605->aout)) {
 		if (PTR_ERR(cm3605->aout) == -ENODEV) {
 			dev_err(dev, "no ADC, deferring...\n");
 			return -EPROBE_DEFER;
 		}
 		dev_err(dev, "failed to get AOUT ADC channel\n");
 		return PTR_ERR(cm3605->aout);
 	}
 	ret = iio_get_channel_type(cm3605->aout, &ch_type);
 	if (ret < 0)
 		return ret;
 	if (ch_type != IIO_VOLTAGE) {
 		dev_err(dev, "wrong type of IIO channel specified for AOUT\n");
 		return -EINVAL;
 	}

 	cm3605->vdd = devm_regulator_get(dev, "vdd");
 	if (IS_ERR(cm3605->vdd)) {
 		dev_err(dev, "failed to get VDD regulator\n");
 		return PTR_ERR(cm3605->vdd);
 	}
 	ret = regulator_enable(cm3605->vdd);
 	if (ret) {
 		dev_err(dev, "failed to enable VDD regulator\n");
 		return ret;
 	}

 	cm3605->aset = devm_gpiod_get(dev, "aset", GPIOD_OUT_HIGH);
 	if (IS_ERR(cm3605->aset)) {
 		dev_err(dev, "no ASET GPIO\n");
 		ret = PTR_ERR(cm3605->aset);
 		goto out_disable_vdd;
 	}

 	ret = devm_request_threaded_irq(dev, platform_get_irq(pdev, 0),
 			cm3605_prox_irq, NULL, 0, "cm3605", indio_dev);
 	if (ret) {
 		dev_err(dev, "unable to request IRQ\n");
 		goto out_disable_aset;
 	}

 	/* Just name the trigger the same as the driver */
 	led_trigger_register_simple("cm3605", &cm3605->led);
 	led_trigger_event(cm3605->led, LED_FULL);

 	indio_dev->dev.parent = dev;
 	indio_dev->info = &cm3605_info;
 	indio_dev->name = "cm3605";
 	indio_dev->channels = cm3605_channels;
 	indio_dev->num_channels = ARRAY_SIZE(cm3605_channels);
 	indio_dev->modes = INDIO_DIRECT_MODE;

 	ret = iio_device_register(indio_dev);
 	if (ret)
 		goto out_remove_trigger;
 	dev_info(dev, "Capella Microsystems CM3605 enabled range 0..%d LUX\n",
 		 cm3605->als_max);

 	return 0;

 out_remove_trigger:
 	led_trigger_event(cm3605->led, LED_OFF);
 	led_trigger_unregister_simple(cm3605->led);
 out_disable_aset:
 	gpiod_set_value_cansleep(cm3605->aset, 0);
 out_disable_vdd:
 	regulator_disable(cm3605->vdd);
 	return ret;
 }

 static int cm3605_remove(struct platform_device *pdev)
 {
 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 	struct cm3605 *cm3605 = iio_priv(indio_dev);

 	led_trigger_event(cm3605->led, LED_OFF);
 	led_trigger_unregister_simple(cm3605->led);
 	gpiod_set_value_cansleep(cm3605->aset, 0);
 	iio_device_unregister(indio_dev);
 	regulator_disable(cm3605->vdd);

 	return 0;
 }

 static int __maybe_unused cm3605_pm_suspend(struct device *dev)
 {
 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 	struct cm3605 *cm3605 = iio_priv(indio_dev);

 	led_trigger_event(cm3605->led, LED_OFF);
 	regulator_disable(cm3605->vdd);

 	return 0;
 }

 static int __maybe_unused cm3605_pm_resume(struct device *dev)
 {
 	struct iio_dev *indio_dev = dev_get_drvdata(dev);
 	struct cm3605 *cm3605 = iio_priv(indio_dev);
 	int ret;

 	ret = regulator_enable(cm3605->vdd);
 	if (ret)
 		dev_err(dev, "failed to enable regulator in resume path\n");
 	led_trigger_event(cm3605->led, LED_FULL);

 	return 0;
 }

 static const struct dev_pm_ops cm3605_dev_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(cm3605_pm_suspend,
 				cm3605_pm_resume)
 };

 static const struct of_device_id cm3605_of_match[] = {
 	{.compatible = "capella,cm3605"},
 	{ },
 };
 MODULE_DEVICE_TABLE(of, cm3605_of_match);

 static struct platform_driver cm3605_driver = {
 	.driver = {
 		.name = "cm3605",
 		.of_match_table = cm3605_of_match,
 		.pm = &cm3605_dev_pm_ops,
 	},
 	.probe = cm3605_probe,
 	.remove = cm3605_remove,
 };
 module_platform_driver(cm3605_driver);

 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
 MODULE_DESCRIPTION("CM3605 ambient light and proximity sensor driver");
 MODULE_LICENSE("GPL");
	/*
	* CM3605 Ambient Light and Proximity Sensor
	*
	* Copyright (C) 2016 Linaro Ltd.
	* Author: Linus Walleij <linus.walleij@linaro.org>
	*
	* This hardware was found in the very first Nexus One handset from Google/HTC
	* and an early endavour into mobile light and proximity sensors.
	*/

	#include <linux/module.h>
	#include <linux/iio/iio.h>
	#include <linux/iio/sysfs.h>
	#include <linux/iio/events.h>
	#include <linux/iio/consumer.h> /* To get our ADC channel */
	#include <linux/iio/types.h> /* To deal with our ADC channel */
	#include <linux/init.h>
	#include <linux/leds.h>
	#include <linux/platform_device.h>
	#include <linux/of.h>
	#include <linux/regulator/consumer.h>
	#include <linux/gpio/consumer.h>
	#include <linux/interrupt.h>
	#include <linux/math64.h>
	#include <linux/pm.h>

	#define CM3605_PROX_CHANNEL 0
	#define CM3605_ALS_CHANNEL 1
	#define CM3605_AOUT_TYP_MAX_MV 1550
	/* It should not go above 1.650V according to the data sheet */
	#define CM3605_AOUT_MAX_MV 1650

	/**
	* struct cm3605 - CM3605 state
	* @dev: pointer to parent device
	* @vdd: regulator controlling VDD
	* @aset: sleep enable GPIO, high = sleep
	* @aout: IIO ADC channel to convert the AOUT signal
	* @als_max: maximum LUX detection (depends on RSET)
	* @dir: proximity direction: start as FALLING
	* @led: trigger for the infrared LED used by the proximity sensor
	*/
	struct cm3605 {
	struct device *dev;
	struct regulator *vdd;
	struct gpio_desc *aset;
	struct iio_channel *aout;
	s32 als_max;
	enum iio_event_direction dir;
	struct led_trigger *led;
	};

	static irqreturn_t cm3605_prox_irq(int irq, void *d)
	{
	struct iio_dev *indio_dev = d;
	struct cm3605 *cm3605 = iio_priv(indio_dev);
	u64 ev;

	ev = IIO_UNMOD_EVENT_CODE(IIO_PROXIMITY, CM3605_PROX_CHANNEL,
	IIO_EV_TYPE_THRESH, cm3605->dir);
	iio_push_event(indio_dev, ev, iio_get_time_ns(indio_dev));

	/* Invert the edge for each event */
	if (cm3605->dir == IIO_EV_DIR_RISING)
	cm3605->dir = IIO_EV_DIR_FALLING;
	else
	cm3605->dir = IIO_EV_DIR_RISING;

	return IRQ_HANDLED;
	}

	static int cm3605_get_lux(struct cm3605 *cm3605)
	{
	int ret, res;
	s64 lux;

	ret = iio_read_channel_processed(cm3605->aout, &res);
	if (ret < 0)
	return ret;

	dev_dbg(cm3605->dev, "read %d mV from ADC\n", res);

	/*
	* AOUT has an offset of ~30mV then linear at dark
	* then goes from 2.54 up to 650 LUX yielding 1.55V
	* (1550 mV) so scale the returned value to this interval
	* using simple linear interpolation.
	*/
	if (res < 30)
	return 0;
	if (res > CM3605_AOUT_MAX_MV)
	dev_err(cm3605->dev, "device out of range\n");

	/* Remove bias */
	lux = res - 30;

	/* Linear interpolation between 0 and ALS typ max */
	lux *= cm3605->als_max;
	lux = div64_s64(lux, CM3605_AOUT_TYP_MAX_MV);

	return lux;
	}

	static int cm3605_read_raw(struct iio_dev *indio_dev,
	struct iio_chan_spec const *chan,
	int val, int val2, long mask)
	{
	struct cm3605 *cm3605 = iio_priv(indio_dev);
	int ret;

	switch (mask) {
	case IIO_CHAN_INFO_RAW:
	switch (chan->type) {
	case IIO_LIGHT:
	ret = cm3605_get_lux(cm3605);
	if (ret < 0)
	return ret;
	*val = ret;
	return IIO_VAL_INT;
	default:
	return -EINVAL;
	}
	default:
	return -EINVAL;
	}
	}

	static const struct iio_info cm3605_info = {
	.read_raw = cm3605_read_raw,
	};

	static const struct iio_event_spec cm3605_events[] = {
	{
	.type = IIO_EV_TYPE_THRESH,
	.dir = IIO_EV_DIR_EITHER,
	.mask_separate = BIT(IIO_EV_INFO_ENABLE),
	},
	};

	static const struct iio_chan_spec cm3605_channels[] = {
	{
	.type = IIO_PROXIMITY,
	.event_spec = cm3605_events,
	.num_event_specs = ARRAY_SIZE(cm3605_events),
	},
	{
	.type = IIO_LIGHT,
	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
	.channel = CM3605_ALS_CHANNEL,
	},
	};

	static int cm3605_probe(struct platform_device *pdev)
	{
	struct cm3605 *cm3605;
	struct iio_dev *indio_dev;
	struct device *dev = &pdev->dev;
	struct device_node *np = dev->of_node;
	enum iio_chan_type ch_type;
	u32 rset;
	int ret;

	indio_dev = devm_iio_device_alloc(dev, sizeof(*cm3605));
	if (!indio_dev)
	return -ENOMEM;
	platform_set_drvdata(pdev, indio_dev);

	cm3605 = iio_priv(indio_dev);
	cm3605->dev = dev;
	cm3605->dir = IIO_EV_DIR_FALLING;

	ret = of_property_read_u32(np, "capella,aset-resistance-ohms", &rset);
	if (ret) {
	dev_info(dev, "no RSET specified, assuming 100K\n");
	rset = 100000;
	}
	switch (rset) {
	case 50000:
	cm3605->als_max = 650;
	break;
	case 100000:
	cm3605->als_max = 300;
	break;
	case 300000:
	cm3605->als_max = 100;
	break;
	case 600000:
	cm3605->als_max = 50;
	break;
	default:
	dev_info(dev, "non-standard resistance\n");
	return -EINVAL;
	}

	cm3605->aout = devm_iio_channel_get(dev, "aout");
	if (IS_ERR(cm3605->aout)) {
	if (PTR_ERR(cm3605->aout) == -ENODEV) {
	dev_err(dev, "no ADC, deferring...\n");
	return -EPROBE_DEFER;
	}
	dev_err(dev, "failed to get AOUT ADC channel\n");
	return PTR_ERR(cm3605->aout);
	}
	ret = iio_get_channel_type(cm3605->aout, &ch_type);
	if (ret < 0)
	return ret;
	if (ch_type != IIO_VOLTAGE) {
	dev_err(dev, "wrong type of IIO channel specified for AOUT\n");
	return -EINVAL;
	}

	cm3605->vdd = devm_regulator_get(dev, "vdd");
	if (IS_ERR(cm3605->vdd)) {
	dev_err(dev, "failed to get VDD regulator\n");
	return PTR_ERR(cm3605->vdd);
	}
	ret = regulator_enable(cm3605->vdd);
	if (ret) {
	dev_err(dev, "failed to enable VDD regulator\n");
	return ret;
	}

	cm3605->aset = devm_gpiod_get(dev, "aset", GPIOD_OUT_HIGH);
	if (IS_ERR(cm3605->aset)) {
	dev_err(dev, "no ASET GPIO\n");
	ret = PTR_ERR(cm3605->aset);
	goto out_disable_vdd;
	}

	ret = devm_request_threaded_irq(dev, platform_get_irq(pdev, 0),
	cm3605_prox_irq, NULL, 0, "cm3605", indio_dev);
	if (ret) {
	dev_err(dev, "unable to request IRQ\n");
	goto out_disable_aset;
	}

	/* Just name the trigger the same as the driver */
	led_trigger_register_simple("cm3605", &cm3605->led);
	led_trigger_event(cm3605->led, LED_FULL);

	indio_dev->dev.parent = dev;
	indio_dev->info = &cm3605_info;
	indio_dev->name = "cm3605";
	indio_dev->channels = cm3605_channels;
	indio_dev->num_channels = ARRAY_SIZE(cm3605_channels);
	indio_dev->modes = INDIO_DIRECT_MODE;

	ret = iio_device_register(indio_dev);
	if (ret)
	goto out_remove_trigger;
	dev_info(dev, "Capella Microsystems CM3605 enabled range 0..%d LUX\n",
	cm3605->als_max);

	return 0;

	out_remove_trigger:
	led_trigger_event(cm3605->led, LED_OFF);
	led_trigger_unregister_simple(cm3605->led);
	out_disable_aset:
	gpiod_set_value_cansleep(cm3605->aset, 0);
	out_disable_vdd:
	regulator_disable(cm3605->vdd);
	return ret;
	}

	static int cm3605_remove(struct platform_device *pdev)
	{
	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
	struct cm3605 *cm3605 = iio_priv(indio_dev);

	led_trigger_event(cm3605->led, LED_OFF);
	led_trigger_unregister_simple(cm3605->led);
	gpiod_set_value_cansleep(cm3605->aset, 0);
	iio_device_unregister(indio_dev);
	regulator_disable(cm3605->vdd);

	return 0;
	}

	static int __maybe_unused cm3605_pm_suspend(struct device *dev)
	{
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct cm3605 *cm3605 = iio_priv(indio_dev);

	led_trigger_event(cm3605->led, LED_OFF);
	regulator_disable(cm3605->vdd);

	return 0;
	}

	static int __maybe_unused cm3605_pm_resume(struct device *dev)
	{
	struct iio_dev *indio_dev = dev_get_drvdata(dev);
	struct cm3605 *cm3605 = iio_priv(indio_dev);
	int ret;

	ret = regulator_enable(cm3605->vdd);
	if (ret)
	dev_err(dev, "failed to enable regulator in resume path\n");
	led_trigger_event(cm3605->led, LED_FULL);

	return 0;
	}

	static const struct dev_pm_ops cm3605_dev_pm_ops = {
	SET_SYSTEM_SLEEP_PM_OPS(cm3605_pm_suspend,
	cm3605_pm_resume)
	};

	static const struct of_device_id cm3605_of_match[] = {
	{.compatible = "capella,cm3605"},
	{ },
	};
	MODULE_DEVICE_TABLE(of, cm3605_of_match);

	static struct platform_driver cm3605_driver = {
	.driver = {
	.name = "cm3605",
	.of_match_table = cm3605_of_match,
	.pm = &cm3605_dev_pm_ops,
	},
	.probe = cm3605_probe,
	.remove = cm3605_remove,
	};
	module_platform_driver(cm3605_driver);

	MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>");
	MODULE_DESCRIPTION("CM3605 ambient light and proximity sensor driver");
	MODULE_LICENSE("GPL");