[mirror_ubuntu-focal-kernel.git] / drivers / hwmon / ntc_thermistor.c

/*
 * ntc_thermistor.c - NTC Thermistors
 *
 *  Copyright (C) 2010 Samsung Electronics
 *  MyungJoo Ham <myungjoo.ham@samsung.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <linux/slab.h>
#include <linux/module.h>
#include <linux/pm_runtime.h>
#include <linux/math64.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/of_device.h>

#include <linux/platform_data/ntc_thermistor.h>

#include <linux/iio/iio.h>
#include <linux/iio/machine.h>
#include <linux/iio/driver.h>
#include <linux/iio/consumer.h>

#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/thermal.h>

struct ntc_compensation {
	int		temp_c;
	unsigned int	ohm;
};

/* Order matters, ntc_match references the entries by index */
static const struct platform_device_id ntc_thermistor_id[] = {
	{ "ncp15wb473", TYPE_NCPXXWB473 },
	{ "ncp18wb473", TYPE_NCPXXWB473 },
	{ "ncp21wb473", TYPE_NCPXXWB473 },
	{ "ncp03wb473", TYPE_NCPXXWB473 },
	{ "ncp15wl333", TYPE_NCPXXWL333 },
	{ "b57330v2103", TYPE_B57330V2103},
	{ },
};

/*
 * A compensation table should be sorted by the values of .ohm
 * in descending order.
 * The following compensation tables are from the specification of Murata NTC
 * Thermistors Datasheet
 */
static const struct ntc_compensation ncpXXwb473[] = {
	{ .temp_c	= -40, .ohm	= 1747920 },
	{ .temp_c	= -35, .ohm	= 1245428 },
	{ .temp_c	= -30, .ohm	= 898485 },
	{ .temp_c	= -25, .ohm	= 655802 },
	{ .temp_c	= -20, .ohm	= 483954 },
	{ .temp_c	= -15, .ohm	= 360850 },
	{ .temp_c	= -10, .ohm	= 271697 },
	{ .temp_c	= -5, .ohm	= 206463 },
	{ .temp_c	= 0, .ohm	= 158214 },
	{ .temp_c	= 5, .ohm	= 122259 },
	{ .temp_c	= 10, .ohm	= 95227 },
	{ .temp_c	= 15, .ohm	= 74730 },
	{ .temp_c	= 20, .ohm	= 59065 },
	{ .temp_c	= 25, .ohm	= 47000 },
	{ .temp_c	= 30, .ohm	= 37643 },
	{ .temp_c	= 35, .ohm	= 30334 },
	{ .temp_c	= 40, .ohm	= 24591 },
	{ .temp_c	= 45, .ohm	= 20048 },
	{ .temp_c	= 50, .ohm	= 16433 },
	{ .temp_c	= 55, .ohm	= 13539 },
	{ .temp_c	= 60, .ohm	= 11209 },
	{ .temp_c	= 65, .ohm	= 9328 },
	{ .temp_c	= 70, .ohm	= 7798 },
	{ .temp_c	= 75, .ohm	= 6544 },
	{ .temp_c	= 80, .ohm	= 5518 },
	{ .temp_c	= 85, .ohm	= 4674 },
	{ .temp_c	= 90, .ohm	= 3972 },
	{ .temp_c	= 95, .ohm	= 3388 },
	{ .temp_c	= 100, .ohm	= 2902 },
	{ .temp_c	= 105, .ohm	= 2494 },
	{ .temp_c	= 110, .ohm	= 2150 },
	{ .temp_c	= 115, .ohm	= 1860 },
	{ .temp_c	= 120, .ohm	= 1615 },
	{ .temp_c	= 125, .ohm	= 1406 },
};
static const struct ntc_compensation ncpXXwl333[] = {
	{ .temp_c	= -40, .ohm	= 1610154 },
	{ .temp_c	= -35, .ohm	= 1130850 },
	{ .temp_c	= -30, .ohm	= 802609 },
	{ .temp_c	= -25, .ohm	= 575385 },
	{ .temp_c	= -20, .ohm	= 416464 },
	{ .temp_c	= -15, .ohm	= 304219 },
	{ .temp_c	= -10, .ohm	= 224193 },
	{ .temp_c	= -5, .ohm	= 166623 },
	{ .temp_c	= 0, .ohm	= 124850 },
	{ .temp_c	= 5, .ohm	= 94287 },
	{ .temp_c	= 10, .ohm	= 71747 },
	{ .temp_c	= 15, .ohm	= 54996 },
	{ .temp_c	= 20, .ohm	= 42455 },
	{ .temp_c	= 25, .ohm	= 33000 },
	{ .temp_c	= 30, .ohm	= 25822 },
	{ .temp_c	= 35, .ohm	= 20335 },
	{ .temp_c	= 40, .ohm	= 16115 },
	{ .temp_c	= 45, .ohm	= 12849 },
	{ .temp_c	= 50, .ohm	= 10306 },
	{ .temp_c	= 55, .ohm	= 8314 },
	{ .temp_c	= 60, .ohm	= 6746 },
	{ .temp_c	= 65, .ohm	= 5503 },
	{ .temp_c	= 70, .ohm	= 4513 },
	{ .temp_c	= 75, .ohm	= 3721 },
	{ .temp_c	= 80, .ohm	= 3084 },
	{ .temp_c	= 85, .ohm	= 2569 },
	{ .temp_c	= 90, .ohm	= 2151 },
	{ .temp_c	= 95, .ohm	= 1809 },
	{ .temp_c	= 100, .ohm	= 1529 },
	{ .temp_c	= 105, .ohm	= 1299 },
	{ .temp_c	= 110, .ohm	= 1108 },
	{ .temp_c	= 115, .ohm	= 949 },
	{ .temp_c	= 120, .ohm	= 817 },
	{ .temp_c	= 125, .ohm	= 707 },
};

/*
 * The following compensation table is from the specification of EPCOS NTC
 * Thermistors Datasheet
 */
static const struct ntc_compensation b57330v2103[] = {
	{ .temp_c	= -40, .ohm	= 190030 },
	{ .temp_c	= -35, .ohm	= 145360 },
	{ .temp_c	= -30, .ohm	= 112060 },
	{ .temp_c	= -25, .ohm	= 87041 },
	{ .temp_c	= -20, .ohm	= 68104 },
	{ .temp_c	= -15, .ohm	= 53665 },
	{ .temp_c	= -10, .ohm	= 42576 },
	{ .temp_c	= -5, .ohm	= 34001 },
	{ .temp_c	= 0, .ohm	= 27326 },
	{ .temp_c	= 5, .ohm	= 22096 },
	{ .temp_c	= 10, .ohm	= 17973 },
	{ .temp_c	= 15, .ohm	= 14703 },
	{ .temp_c	= 20, .ohm	= 12090 },
	{ .temp_c	= 25, .ohm	= 10000 },
	{ .temp_c	= 30, .ohm	= 8311 },
	{ .temp_c	= 35, .ohm	= 6941 },
	{ .temp_c	= 40, .ohm	= 5825 },
	{ .temp_c	= 45, .ohm	= 4911 },
	{ .temp_c	= 50, .ohm	= 4158 },
	{ .temp_c	= 55, .ohm	= 3536 },
	{ .temp_c	= 60, .ohm	= 3019 },
	{ .temp_c	= 65, .ohm	= 2588 },
	{ .temp_c	= 70, .ohm	= 2227 },
	{ .temp_c	= 75, .ohm	= 1924 },
	{ .temp_c	= 80, .ohm	= 1668 },
	{ .temp_c	= 85, .ohm	= 1451 },
	{ .temp_c	= 90, .ohm	= 1266 },
	{ .temp_c	= 95, .ohm	= 1108 },
	{ .temp_c	= 100, .ohm	= 973 },
	{ .temp_c	= 105, .ohm	= 857 },
	{ .temp_c	= 110, .ohm	= 757 },
	{ .temp_c	= 115, .ohm	= 671 },
	{ .temp_c	= 120, .ohm	= 596 },
	{ .temp_c	= 125, .ohm	= 531 },
};

struct ntc_data {
	struct device *hwmon_dev;
	struct ntc_thermistor_platform_data *pdata;
	const struct ntc_compensation *comp;
	struct device *dev;
	int n_comp;
	char name[PLATFORM_NAME_SIZE];
	struct thermal_zone_device *tz;
};

#if defined(CONFIG_OF) && IS_ENABLED(CONFIG_IIO)
static int ntc_adc_iio_read(struct ntc_thermistor_platform_data *pdata)
{
	struct iio_channel *channel = pdata->chan;
	s64 result;
	int val, ret;

	ret = iio_read_channel_raw(channel, &val);
	if (ret < 0) {
		pr_err("read channel() error: %d\n", ret);
		return ret;
	}

	/* unit: mV */
	result = pdata->pullup_uv * (s64) val;
	result >>= 12;

	return (int)result;
}

static const struct of_device_id ntc_match[] = {
	{ .compatible = "murata,ncp15wb473",
		.data = &ntc_thermistor_id[0] },
	{ .compatible = "murata,ncp18wb473",
		.data = &ntc_thermistor_id[1] },
	{ .compatible = "murata,ncp21wb473",
		.data = &ntc_thermistor_id[2] },
	{ .compatible = "murata,ncp03wb473",
		.data = &ntc_thermistor_id[3] },
	{ .compatible = "murata,ncp15wl333",
		.data = &ntc_thermistor_id[4] },
	{ .compatible = "epcos,b57330v2103",
		.data = &ntc_thermistor_id[5]},

	/* Usage of vendor name "ntc" is deprecated */
	{ .compatible = "ntc,ncp15wb473",
		.data = &ntc_thermistor_id[0] },
	{ .compatible = "ntc,ncp18wb473",
		.data = &ntc_thermistor_id[1] },
	{ .compatible = "ntc,ncp21wb473",
		.data = &ntc_thermistor_id[2] },
	{ .compatible = "ntc,ncp03wb473",
		.data = &ntc_thermistor_id[3] },
	{ .compatible = "ntc,ncp15wl333",
		.data = &ntc_thermistor_id[4] },
	{ },
};
MODULE_DEVICE_TABLE(of, ntc_match);

static struct ntc_thermistor_platform_data *
ntc_thermistor_parse_dt(struct platform_device *pdev)
{
	struct iio_channel *chan;
	enum iio_chan_type type;
	struct device_node *np = pdev->dev.of_node;
	struct ntc_thermistor_platform_data *pdata;
	int ret;

	if (!np)
		return NULL;

	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
	if (!pdata)
		return ERR_PTR(-ENOMEM);

	chan = iio_channel_get(&pdev->dev, NULL);
	if (IS_ERR(chan))
		return ERR_CAST(chan);

	ret = iio_get_channel_type(chan, &type);
	if (ret < 0)
		return ERR_PTR(ret);

	if (type != IIO_VOLTAGE)
		return ERR_PTR(-EINVAL);

	if (of_property_read_u32(np, "pullup-uv", &pdata->pullup_uv))
		return ERR_PTR(-ENODEV);
	if (of_property_read_u32(np, "pullup-ohm", &pdata->pullup_ohm))
		return ERR_PTR(-ENODEV);
	if (of_property_read_u32(np, "pulldown-ohm", &pdata->pulldown_ohm))
		return ERR_PTR(-ENODEV);

	if (of_find_property(np, "connected-positive", NULL))
		pdata->connect = NTC_CONNECTED_POSITIVE;
	else /* status change should be possible if not always on. */
		pdata->connect = NTC_CONNECTED_GROUND;

	pdata->chan = chan;
	pdata->read_uv = ntc_adc_iio_read;

	return pdata;
}
static void ntc_iio_channel_release(struct ntc_thermistor_platform_data *pdata)
{
	if (pdata->chan)
		iio_channel_release(pdata->chan);
}
#else
static struct ntc_thermistor_platform_data *
ntc_thermistor_parse_dt(struct platform_device *pdev)
{
	return NULL;
}

#define ntc_match	NULL

static void ntc_iio_channel_release(struct ntc_thermistor_platform_data *pdata)
{ }
#endif

static inline u64 div64_u64_safe(u64 dividend, u64 divisor)
{
	if (divisor == 0 && dividend == 0)
		return 0;
	if (divisor == 0)
		return UINT_MAX;
	return div64_u64(dividend, divisor);
}

static int get_ohm_of_thermistor(struct ntc_data *data, unsigned int uv)
{
	struct ntc_thermistor_platform_data *pdata = data->pdata;
	u64 mv = uv / 1000;
	u64 pmv = pdata->pullup_uv / 1000;
	u64 n, puo, pdo;
	puo = pdata->pullup_ohm;
	pdo = pdata->pulldown_ohm;

	if (mv == 0) {
		if (pdata->connect == NTC_CONNECTED_POSITIVE)
			return INT_MAX;
		return 0;
	}
	if (mv >= pmv)
		return (pdata->connect == NTC_CONNECTED_POSITIVE) ?
			0 : INT_MAX;

	if (pdata->connect == NTC_CONNECTED_POSITIVE && puo == 0)
		n = div64_u64_safe(pdo * (pmv - mv), mv);
	else if (pdata->connect == NTC_CONNECTED_GROUND && pdo == 0)
		n = div64_u64_safe(puo * mv, pmv - mv);
	else if (pdata->connect == NTC_CONNECTED_POSITIVE)
		n = div64_u64_safe(pdo * puo * (pmv - mv),
				puo * mv - pdo * (pmv - mv));
	else
		n = div64_u64_safe(pdo * puo * mv, pdo * (pmv - mv) - puo * mv);

	if (n > INT_MAX)
		n = INT_MAX;
	return n;
}

static void lookup_comp(struct ntc_data *data, unsigned int ohm,
			int *i_low, int *i_high)
{
	int start, end, mid;

	/*
	 * Handle special cases: Resistance is higher than or equal to
	 * resistance in first table entry, or resistance is lower or equal
	 * to resistance in last table entry.
	 * In these cases, return i_low == i_high, either pointing to the
	 * beginning or to the end of the table depending on the condition.
	 */
	if (ohm >= data->comp[0].ohm) {
		*i_low = 0;
		*i_high = 0;
		return;
	}
	if (ohm <= data->comp[data->n_comp - 1].ohm) {
		*i_low = data->n_comp - 1;
		*i_high = data->n_comp - 1;
		return;
	}

	/* Do a binary search on compensation table */
	start = 0;
	end = data->n_comp;
	while (start < end) {
		mid = start + (end - start) / 2;
		/*
		 * start <= mid < end
		 * data->comp[start].ohm > ohm >= data->comp[end].ohm
		 *
		 * We could check for "ohm == data->comp[mid].ohm" here, but
		 * that is a quite unlikely condition, and we would have to
		 * check again after updating start. Check it at the end instead
		 * for simplicity.
		 */
		if (ohm >= data->comp[mid].ohm) {
			end = mid;
		} else {
			start = mid + 1;
			/*
			 * ohm >= data->comp[start].ohm might be true here,
			 * since we set start to mid + 1. In that case, we are
			 * done. We could keep going, but the condition is quite
			 * likely to occur, so it is worth checking for it.
			 */
			if (ohm >= data->comp[start].ohm)
				end = start;
		}
		/*
		 * start <= end
		 * data->comp[start].ohm >= ohm >= data->comp[end].ohm
		 */
	}
	/*
	 * start == end
	 * ohm >= data->comp[end].ohm
	 */
	*i_low = end;
	if (ohm == data->comp[end].ohm)
		*i_high = end;
	else
		*i_high = end - 1;
}

static int get_temp_mc(struct ntc_data *data, unsigned int ohm)
{
	int low, high;
	int temp;

	lookup_comp(data, ohm, &low, &high);
	if (low == high) {
		/* Unable to use linear approximation */
		temp = data->comp[low].temp_c * 1000;
	} else {
		temp = data->comp[low].temp_c * 1000 +
			((data->comp[high].temp_c - data->comp[low].temp_c) *
			 1000 * ((int)ohm - (int)data->comp[low].ohm)) /
			((int)data->comp[high].ohm - (int)data->comp[low].ohm);
	}
	return temp;
}

static int ntc_thermistor_get_ohm(struct ntc_data *data)
{
	int read_uv;

	if (data->pdata->read_ohm)
		return data->pdata->read_ohm();

	if (data->pdata->read_uv) {
		read_uv = data->pdata->read_uv(data->pdata);
		if (read_uv < 0)
			return read_uv;
		return get_ohm_of_thermistor(data, read_uv);
	}
	return -EINVAL;
}

static int ntc_read_temp(void *dev, long *temp)
{
	struct ntc_data *data = dev_get_drvdata(dev);
	int ohm;

	ohm = ntc_thermistor_get_ohm(data);
	if (ohm < 0)
		return ohm;

	*temp = get_temp_mc(data, ohm);

	return 0;
}

static ssize_t ntc_show_name(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct ntc_data *data = dev_get_drvdata(dev);

	return sprintf(buf, "%s\n", data->name);
}

static ssize_t ntc_show_type(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	return sprintf(buf, "4\n");
}

static ssize_t ntc_show_temp(struct device *dev,
		struct device_attribute *attr, char *buf)
{
	struct ntc_data *data = dev_get_drvdata(dev);
	int ohm;

	ohm = ntc_thermistor_get_ohm(data);
	if (ohm < 0)
		return ohm;

	return sprintf(buf, "%d\n", get_temp_mc(data, ohm));
}

static SENSOR_DEVICE_ATTR(temp1_type, S_IRUGO, ntc_show_type, NULL, 0);
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, ntc_show_temp, NULL, 0);
static DEVICE_ATTR(name, S_IRUGO, ntc_show_name, NULL);

static struct attribute *ntc_attributes[] = {
	&dev_attr_name.attr,
	&sensor_dev_attr_temp1_type.dev_attr.attr,
	&sensor_dev_attr_temp1_input.dev_attr.attr,
	NULL,
};

static const struct attribute_group ntc_attr_group = {
	.attrs = ntc_attributes,
};

static const struct thermal_zone_of_device_ops ntc_of_thermal_ops = {
	.get_temp = ntc_read_temp,
};

static int ntc_thermistor_probe(struct platform_device *pdev)
{
	const struct of_device_id *of_id =
			of_match_device(of_match_ptr(ntc_match), &pdev->dev);
	const struct platform_device_id *pdev_id;
	struct ntc_thermistor_platform_data *pdata;
	struct ntc_data *data;
	int ret;

	pdata = ntc_thermistor_parse_dt(pdev);
	if (IS_ERR(pdata))
		return PTR_ERR(pdata);
	else if (pdata == NULL)
		pdata = dev_get_platdata(&pdev->dev);

	if (!pdata) {
		dev_err(&pdev->dev, "No platform init data supplied.\n");
		return -ENODEV;
	}

	/* Either one of the two is required. */
	if (!pdata->read_uv && !pdata->read_ohm) {
		dev_err(&pdev->dev,
			"Both read_uv and read_ohm missing. Need either one of the two.\n");
		return -EINVAL;
	}

	if (pdata->read_uv && pdata->read_ohm) {
		dev_warn(&pdev->dev,
			 "Only one of read_uv and read_ohm is needed; ignoring read_uv.\n");
		pdata->read_uv = NULL;
	}

	if (pdata->read_uv && (pdata->pullup_uv == 0 ||
				(pdata->pullup_ohm == 0 && pdata->connect ==
				 NTC_CONNECTED_GROUND) ||
				(pdata->pulldown_ohm == 0 && pdata->connect ==
				 NTC_CONNECTED_POSITIVE) ||
				(pdata->connect != NTC_CONNECTED_POSITIVE &&
				 pdata->connect != NTC_CONNECTED_GROUND))) {
		dev_err(&pdev->dev,
			"Required data to use read_uv not supplied.\n");
		return -EINVAL;
	}

	data = devm_kzalloc(&pdev->dev, sizeof(struct ntc_data), GFP_KERNEL);
	if (!data)
		return -ENOMEM;

	pdev_id = of_id ? of_id->data : platform_get_device_id(pdev);

	data->dev = &pdev->dev;
	data->pdata = pdata;
	strlcpy(data->name, pdev_id->name, sizeof(data->name));

	switch (pdev_id->driver_data) {
	case TYPE_NCPXXWB473:
		data->comp = ncpXXwb473;
		data->n_comp = ARRAY_SIZE(ncpXXwb473);
		break;
	case TYPE_NCPXXWL333:
		data->comp = ncpXXwl333;
		data->n_comp = ARRAY_SIZE(ncpXXwl333);
		break;
	case TYPE_B57330V2103:
		data->comp = b57330v2103;
		data->n_comp = ARRAY_SIZE(b57330v2103);
		break;
	default:
		dev_err(&pdev->dev, "Unknown device type: %lu(%s)\n",
				pdev_id->driver_data, pdev_id->name);
		return -EINVAL;
	}

	platform_set_drvdata(pdev, data);

	ret = sysfs_create_group(&data->dev->kobj, &ntc_attr_group);
	if (ret) {
		dev_err(data->dev, "unable to create sysfs files\n");
		return ret;
	}

	data->hwmon_dev = hwmon_device_register(data->dev);
	if (IS_ERR(data->hwmon_dev)) {
		dev_err(data->dev, "unable to register as hwmon device.\n");
		ret = PTR_ERR(data->hwmon_dev);
		goto err_after_sysfs;
	}

	dev_info(&pdev->dev, "Thermistor type: %s successfully probed.\n",
								pdev_id->name);

	data->tz = thermal_zone_of_sensor_register(data->dev, 0, data->dev,
						   &ntc_of_thermal_ops);
	if (IS_ERR(data->tz)) {
		dev_dbg(&pdev->dev, "Failed to register to thermal fw.\n");
		data->tz = NULL;
	}

	return 0;
err_after_sysfs:
	sysfs_remove_group(&data->dev->kobj, &ntc_attr_group);
	ntc_iio_channel_release(pdata);
	return ret;
}

static int ntc_thermistor_remove(struct platform_device *pdev)
{
	struct ntc_data *data = platform_get_drvdata(pdev);
	struct ntc_thermistor_platform_data *pdata = data->pdata;

	hwmon_device_unregister(data->hwmon_dev);
	sysfs_remove_group(&data->dev->kobj, &ntc_attr_group);
	ntc_iio_channel_release(pdata);

	thermal_zone_of_sensor_unregister(data->dev, data->tz);

	return 0;
}

static struct platform_driver ntc_thermistor_driver = {
	.driver = {
		.name = "ntc-thermistor",
		.of_match_table = of_match_ptr(ntc_match),
	},
	.probe = ntc_thermistor_probe,
	.remove = ntc_thermistor_remove,
	.id_table = ntc_thermistor_id,
};

module_platform_driver(ntc_thermistor_driver);

MODULE_DESCRIPTION("NTC Thermistor Driver");
MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:ntc-thermistor");
Commit	Line	Data
f22aaaa7 DK	1	/*
	2	* ntc_thermistor.c - NTC Thermistors
	3	*
	4	* Copyright (C) 2010 Samsung Electronics
	5	* MyungJoo Ham <myungjoo.ham@samsung.com>
	6	*
	7	* This program is free software; you can redistribute it and/or modify
	8	* it under the terms of the GNU General Public License as published by
	9	* the Free Software Foundation; either version 2 of the License, or
	10	* (at your option) any later version.
	11	*
	12	* This program is distributed in the hope that it will be useful,
	13	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	14	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	15	* GNU General Public License for more details.
	16	*
	17	* You should have received a copy of the GNU General Public License
	18	* along with this program; if not, write to the Free Software
	19	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
	20	*
	21	*/
	22
	23	#include <linux/slab.h>
	24	#include <linux/module.h>
	25	#include <linux/pm_runtime.h>
	26	#include <linux/math64.h>
	27	#include <linux/platform_device.h>
	28	#include <linux/err.h>
9e8269de NKC	29	#include <linux/of.h>
9e8269de NKC	30	#include <linux/of_device.h>
f22aaaa7 DK	31
	32	#include <linux/platform_data/ntc_thermistor.h>
	33
9e8269de NKC	34	#include <linux/iio/iio.h>
	35	#include <linux/iio/machine.h>
	36	#include <linux/iio/driver.h>
	37	#include <linux/iio/consumer.h>
	38
f22aaaa7 DK	39	#include <linux/hwmon.h>
f22aaaa7 DK	40	#include <linux/hwmon-sysfs.h>
c08860ff	41	#include <linux/thermal.h>
f22aaaa7 DK	42
f22aaaa7 DK	43	struct ntc_compensation {
088ce2ac	44	int temp_c;
f22aaaa7 DK	45	unsigned int ohm;
	46	};
	47
ead82d67	48	/* Order matters, ntc_match references the entries by index */
9e8269de NKC	49	static const struct platform_device_id ntc_thermistor_id[] = {
	50	{ "ncp15wb473", TYPE_NCPXXWB473 },
	51	{ "ncp18wb473", TYPE_NCPXXWB473 },
	52	{ "ncp21wb473", TYPE_NCPXXWB473 },
	53	{ "ncp03wb473", TYPE_NCPXXWB473 },
	54	{ "ncp15wl333", TYPE_NCPXXWL333 },
ed67f087	55	{ "b57330v2103", TYPE_B57330V2103},
9e8269de NKC	56	{ },
	57	};
	58
f22aaaa7 DK	59	/*
	60	* A compensation table should be sorted by the values of .ohm
	61	* in descending order.
	62	* The following compensation tables are from the specification of Murata NTC
	63	* Thermistors Datasheet
	64	*/
4626dcff	65	static const struct ntc_compensation ncpXXwb473[] = {
088ce2ac GR	66	{ .temp_c = -40, .ohm = 1747920 },
	67	{ .temp_c = -35, .ohm = 1245428 },
	68	{ .temp_c = -30, .ohm = 898485 },
	69	{ .temp_c = -25, .ohm = 655802 },
	70	{ .temp_c = -20, .ohm = 483954 },
	71	{ .temp_c = -15, .ohm = 360850 },
	72	{ .temp_c = -10, .ohm = 271697 },
	73	{ .temp_c = -5, .ohm = 206463 },
	74	{ .temp_c = 0, .ohm = 158214 },
	75	{ .temp_c = 5, .ohm = 122259 },
	76	{ .temp_c = 10, .ohm = 95227 },
	77	{ .temp_c = 15, .ohm = 74730 },
	78	{ .temp_c = 20, .ohm = 59065 },
	79	{ .temp_c = 25, .ohm = 47000 },
	80	{ .temp_c = 30, .ohm = 37643 },
	81	{ .temp_c = 35, .ohm = 30334 },
	82	{ .temp_c = 40, .ohm = 24591 },
	83	{ .temp_c = 45, .ohm = 20048 },
	84	{ .temp_c = 50, .ohm = 16433 },
	85	{ .temp_c = 55, .ohm = 13539 },
	86	{ .temp_c = 60, .ohm = 11209 },
	87	{ .temp_c = 65, .ohm = 9328 },
	88	{ .temp_c = 70, .ohm = 7798 },
	89	{ .temp_c = 75, .ohm = 6544 },
	90	{ .temp_c = 80, .ohm = 5518 },
	91	{ .temp_c = 85, .ohm = 4674 },
	92	{ .temp_c = 90, .ohm = 3972 },
	93	{ .temp_c = 95, .ohm = 3388 },
	94	{ .temp_c = 100, .ohm = 2902 },
	95	{ .temp_c = 105, .ohm = 2494 },
	96	{ .temp_c = 110, .ohm = 2150 },
	97	{ .temp_c = 115, .ohm = 1860 },
	98	{ .temp_c = 120, .ohm = 1615 },
	99	{ .temp_c = 125, .ohm = 1406 },
f22aaaa7	100	};
4626dcff	101	static const struct ntc_compensation ncpXXwl333[] = {
088ce2ac GR	102	{ .temp_c = -40, .ohm = 1610154 },
	103	{ .temp_c = -35, .ohm = 1130850 },
	104	{ .temp_c = -30, .ohm = 802609 },
	105	{ .temp_c = -25, .ohm = 575385 },
	106	{ .temp_c = -20, .ohm = 416464 },
	107	{ .temp_c = -15, .ohm = 304219 },
	108	{ .temp_c = -10, .ohm = 224193 },
	109	{ .temp_c = -5, .ohm = 166623 },
	110	{ .temp_c = 0, .ohm = 124850 },
	111	{ .temp_c = 5, .ohm = 94287 },
	112	{ .temp_c = 10, .ohm = 71747 },
	113	{ .temp_c = 15, .ohm = 54996 },
	114	{ .temp_c = 20, .ohm = 42455 },
	115	{ .temp_c = 25, .ohm = 33000 },
	116	{ .temp_c = 30, .ohm = 25822 },
	117	{ .temp_c = 35, .ohm = 20335 },
	118	{ .temp_c = 40, .ohm = 16115 },
	119	{ .temp_c = 45, .ohm = 12849 },
	120	{ .temp_c = 50, .ohm = 10306 },
	121	{ .temp_c = 55, .ohm = 8314 },
	122	{ .temp_c = 60, .ohm = 6746 },
	123	{ .temp_c = 65, .ohm = 5503 },
	124	{ .temp_c = 70, .ohm = 4513 },
	125	{ .temp_c = 75, .ohm = 3721 },
	126	{ .temp_c = 80, .ohm = 3084 },
	127	{ .temp_c = 85, .ohm = 2569 },
	128	{ .temp_c = 90, .ohm = 2151 },
	129	{ .temp_c = 95, .ohm = 1809 },
	130	{ .temp_c = 100, .ohm = 1529 },
	131	{ .temp_c = 105, .ohm = 1299 },
	132	{ .temp_c = 110, .ohm = 1108 },
	133	{ .temp_c = 115, .ohm = 949 },
	134	{ .temp_c = 120, .ohm = 817 },
	135	{ .temp_c = 125, .ohm = 707 },
f22aaaa7 DK	136	};
f22aaaa7 DK	137
ed67f087 JP	138	/*
	139	* The following compensation table is from the specification of EPCOS NTC
	140	* Thermistors Datasheet
	141	*/
	142	static const struct ntc_compensation b57330v2103[] = {
	143	{ .temp_c = -40, .ohm = 190030 },
	144	{ .temp_c = -35, .ohm = 145360 },
	145	{ .temp_c = -30, .ohm = 112060 },
	146	{ .temp_c = -25, .ohm = 87041 },
	147	{ .temp_c = -20, .ohm = 68104 },
	148	{ .temp_c = -15, .ohm = 53665 },
	149	{ .temp_c = -10, .ohm = 42576 },
	150	{ .temp_c = -5, .ohm = 34001 },
	151	{ .temp_c = 0, .ohm = 27326 },
	152	{ .temp_c = 5, .ohm = 22096 },
	153	{ .temp_c = 10, .ohm = 17973 },
	154	{ .temp_c = 15, .ohm = 14703 },
	155	{ .temp_c = 20, .ohm = 12090 },
	156	{ .temp_c = 25, .ohm = 10000 },
	157	{ .temp_c = 30, .ohm = 8311 },
	158	{ .temp_c = 35, .ohm = 6941 },
	159	{ .temp_c = 40, .ohm = 5825 },
	160	{ .temp_c = 45, .ohm = 4911 },
	161	{ .temp_c = 50, .ohm = 4158 },
	162	{ .temp_c = 55, .ohm = 3536 },
	163	{ .temp_c = 60, .ohm = 3019 },
	164	{ .temp_c = 65, .ohm = 2588 },
	165	{ .temp_c = 70, .ohm = 2227 },
	166	{ .temp_c = 75, .ohm = 1924 },
	167	{ .temp_c = 80, .ohm = 1668 },
	168	{ .temp_c = 85, .ohm = 1451 },
	169	{ .temp_c = 90, .ohm = 1266 },
	170	{ .temp_c = 95, .ohm = 1108 },
	171	{ .temp_c = 100, .ohm = 973 },
	172	{ .temp_c = 105, .ohm = 857 },
	173	{ .temp_c = 110, .ohm = 757 },
	174	{ .temp_c = 115, .ohm = 671 },
	175	{ .temp_c = 120, .ohm = 596 },
	176	{ .temp_c = 125, .ohm = 531 },
	177	};
	178
f22aaaa7 DK	179	struct ntc_data {
	180	struct device *hwmon_dev;
	181	struct ntc_thermistor_platform_data *pdata;
	182	const struct ntc_compensation *comp;
	183	struct device *dev;
	184	int n_comp;
	185	char name[PLATFORM_NAME_SIZE];
c08860ff	186	struct thermal_zone_device *tz;
f22aaaa7 DK	187	};
f22aaaa7 DK	188
59cf4243	189	#if defined(CONFIG_OF) && IS_ENABLED(CONFIG_IIO)
9e8269de NKC	190	static int ntc_adc_iio_read(struct ntc_thermistor_platform_data *pdata)
	191	{
	192	struct iio_channel *channel = pdata->chan;
d3d89c46	193	s64 result;
9e8269de NKC	194	int val, ret;
	195
	196	ret = iio_read_channel_raw(channel, &val);
	197	if (ret < 0) {
	198	pr_err("read channel() error: %d\n", ret);
	199	return ret;
	200	}
	201
	202	/* unit: mV */
d3d89c46	203	result = pdata->pullup_uv * (s64) val;
9e8269de NKC	204	result >>= 12;
9e8269de NKC	205
d3d89c46	206	return (int)result;
9e8269de NKC	207	}
	208
	209	static const struct of_device_id ntc_match[] = {
8b6f5e0f NKC	210	{ .compatible = "murata,ncp15wb473",
	211	.data = &ntc_thermistor_id[0] },
	212	{ .compatible = "murata,ncp18wb473",
	213	.data = &ntc_thermistor_id[1] },
	214	{ .compatible = "murata,ncp21wb473",
	215	.data = &ntc_thermistor_id[2] },
	216	{ .compatible = "murata,ncp03wb473",
	217	.data = &ntc_thermistor_id[3] },
	218	{ .compatible = "murata,ncp15wl333",
	219	.data = &ntc_thermistor_id[4] },
ed67f087 JP	220	{ .compatible = "epcos,b57330v2103",
ed67f087 JP	221	.data = &ntc_thermistor_id[5]},
8b6f5e0f NKC	222
8b6f5e0f NKC	223	/* Usage of vendor name "ntc" is deprecated */
9e8269de	224	{ .compatible = "ntc,ncp15wb473",
ead82d67	225	.data = &ntc_thermistor_id[0] },
9e8269de	226	{ .compatible = "ntc,ncp18wb473",
ead82d67	227	.data = &ntc_thermistor_id[1] },
9e8269de	228	{ .compatible = "ntc,ncp21wb473",
ead82d67	229	.data = &ntc_thermistor_id[2] },
9e8269de	230	{ .compatible = "ntc,ncp03wb473",
ead82d67	231	.data = &ntc_thermistor_id[3] },
9e8269de	232	{ .compatible = "ntc,ncp15wl333",
ead82d67	233	.data = &ntc_thermistor_id[4] },
9e8269de NKC	234	{ },
	235	};
	236	MODULE_DEVICE_TABLE(of, ntc_match);
	237
	238	static struct ntc_thermistor_platform_data *
	239	ntc_thermistor_parse_dt(struct platform_device *pdev)
	240	{
	241	struct iio_channel *chan;
adba6575	242	enum iio_chan_type type;
9e8269de NKC	243	struct device_node *np = pdev->dev.of_node;
9e8269de NKC	244	struct ntc_thermistor_platform_data *pdata;
adba6575	245	int ret;
9e8269de NKC	246
	247	if (!np)
	248	return NULL;
	249
	250	pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
	251	if (!pdata)
	252	return ERR_PTR(-ENOMEM);
	253
	254	chan = iio_channel_get(&pdev->dev, NULL);
	255	if (IS_ERR(chan))
	256	return ERR_CAST(chan);
	257
adba6575 CL	258	ret = iio_get_channel_type(chan, &type);
	259	if (ret < 0)
	260	return ERR_PTR(ret);
	261
	262	if (type != IIO_VOLTAGE)
	263	return ERR_PTR(-EINVAL);
	264
088ce2ac	265	if (of_property_read_u32(np, "pullup-uv", &pdata->pullup_uv))
9e8269de NKC	266	return ERR_PTR(-ENODEV);
	267	if (of_property_read_u32(np, "pullup-ohm", &pdata->pullup_ohm))
	268	return ERR_PTR(-ENODEV);
	269	if (of_property_read_u32(np, "pulldown-ohm", &pdata->pulldown_ohm))
	270	return ERR_PTR(-ENODEV);
	271
	272	if (of_find_property(np, "connected-positive", NULL))
	273	pdata->connect = NTC_CONNECTED_POSITIVE;
	274	else /* status change should be possible if not always on. */
	275	pdata->connect = NTC_CONNECTED_GROUND;
	276
	277	pdata->chan = chan;
088ce2ac	278	pdata->read_uv = ntc_adc_iio_read;
9e8269de NKC	279
	280	return pdata;
	281	}
	282	static void ntc_iio_channel_release(struct ntc_thermistor_platform_data *pdata)
	283	{
	284	if (pdata->chan)
	285	iio_channel_release(pdata->chan);
	286	}
	287	#else
	288	static struct ntc_thermistor_platform_data *
	289	ntc_thermistor_parse_dt(struct platform_device *pdev)
	290	{
	291	return NULL;
	292	}
	293
59cf4243 JD	294	#define ntc_match NULL
59cf4243 JD	295
9e8269de NKC	296	static void ntc_iio_channel_release(struct ntc_thermistor_platform_data *pdata)
	297	{ }
	298	#endif
	299
f22aaaa7 DK	300	static inline u64 div64_u64_safe(u64 dividend, u64 divisor)
	301	{
	302	if (divisor == 0 && dividend == 0)
	303	return 0;
	304	if (divisor == 0)
	305	return UINT_MAX;
	306	return div64_u64(dividend, divisor);
	307	}
	308
088ce2ac	309	static int get_ohm_of_thermistor(struct ntc_data *data, unsigned int uv)
f22aaaa7 DK	310	{
f22aaaa7 DK	311	struct ntc_thermistor_platform_data *pdata = data->pdata;
088ce2ac GR	312	u64 mv = uv / 1000;
	313	u64 pmv = pdata->pullup_uv / 1000;
	314	u64 n, puo, pdo;
	315	puo = pdata->pullup_ohm;
	316	pdo = pdata->pulldown_ohm;
f22aaaa7	317
088ce2ac	318	if (mv == 0) {
f22aaaa7	319	if (pdata->connect == NTC_CONNECTED_POSITIVE)
dbe43a62	320	return INT_MAX;
f22aaaa7 DK	321	return 0;
f22aaaa7 DK	322	}
088ce2ac	323	if (mv >= pmv)
f22aaaa7	324	return (pdata->connect == NTC_CONNECTED_POSITIVE) ?
dbe43a62	325	0 : INT_MAX;
f22aaaa7	326
088ce2ac GR	327	if (pdata->connect == NTC_CONNECTED_POSITIVE && puo == 0)
	328	n = div64_u64_safe(pdo * (pmv - mv), mv);
	329	else if (pdata->connect == NTC_CONNECTED_GROUND && pdo == 0)
	330	n = div64_u64_safe(puo * mv, pmv - mv);
f22aaaa7	331	else if (pdata->connect == NTC_CONNECTED_POSITIVE)
088ce2ac GR	332	n = div64_u64_safe(pdo * puo * (pmv - mv),
088ce2ac GR	333	puo * mv - pdo * (pmv - mv));
f22aaaa7	334	else
088ce2ac	335	n = div64_u64_safe(pdo * puo * mv, pdo * (pmv - mv) - puo * mv);
f22aaaa7	336
088ce2ac GR	337	if (n > INT_MAX)
	338	n = INT_MAX;
	339	return n;
f22aaaa7 DK	340	}
f22aaaa7 DK	341
dbe43a62 GR	342	static void lookup_comp(struct ntc_data *data, unsigned int ohm,
dbe43a62 GR	343	int i_low, int i_high)
f22aaaa7	344	{
dbe43a62 GR	345	int start, end, mid;
	346
	347	/*
	348	* Handle special cases: Resistance is higher than or equal to
	349	* resistance in first table entry, or resistance is lower or equal
	350	* to resistance in last table entry.
	351	* In these cases, return i_low == i_high, either pointing to the
	352	* beginning or to the end of the table depending on the condition.
	353	*/
	354	if (ohm >= data->comp[0].ohm) {
	355	*i_low = 0;
	356	*i_high = 0;
	357	return;
	358	}
	359	if (ohm <= data->comp[data->n_comp - 1].ohm) {
	360	*i_low = data->n_comp - 1;
	361	*i_high = data->n_comp - 1;
	362	return;
	363	}
f22aaaa7 DK	364
	365	/* Do a binary search on compensation table */
	366	start = 0;
	367	end = data->n_comp;
dbe43a62	368	while (start < end) {
f22aaaa7	369	mid = start + (end - start) / 2;
dbe43a62 GR	370	/*
	371	* start <= mid < end
	372	* data->comp[start].ohm > ohm >= data->comp[end].ohm
	373	*
	374	* We could check for "ohm == data->comp[mid].ohm" here, but
	375	* that is a quite unlikely condition, and we would have to
	376	* check again after updating start. Check it at the end instead
	377	* for simplicity.
	378	*/
	379	if (ohm >= data->comp[mid].ohm) {
f22aaaa7	380	end = mid;
f22aaaa7	381	} else {
dbe43a62 GR	382	start = mid + 1;
	383	/*
	384	* ohm >= data->comp[start].ohm might be true here,
	385	* since we set start to mid + 1. In that case, we are
	386	* done. We could keep going, but the condition is quite
	387	* likely to occur, so it is worth checking for it.
	388	*/
	389	if (ohm >= data->comp[start].ohm)
	390	end = start;
f22aaaa7	391	}
dbe43a62 GR	392	/*
	393	* start <= end
	394	* data->comp[start].ohm >= ohm >= data->comp[end].ohm
	395	*/
f22aaaa7	396	}
dbe43a62 GR	397	/*
	398	* start == end
	399	* ohm >= data->comp[end].ohm
	400	*/
	401	*i_low = end;
	402	if (ohm == data->comp[end].ohm)
	403	*i_high = end;
	404	else
	405	*i_high = end - 1;
f22aaaa7 DK	406	}
f22aaaa7 DK	407
088ce2ac	408	static int get_temp_mc(struct ntc_data *data, unsigned int ohm)
f22aaaa7 DK	409	{
f22aaaa7 DK	410	int low, high;
dbe43a62	411	int temp;
f22aaaa7	412
dbe43a62 GR	413	lookup_comp(data, ohm, &low, &high);
dbe43a62 GR	414	if (low == high) {
f22aaaa7	415	/* Unable to use linear approximation */
088ce2ac	416	temp = data->comp[low].temp_c * 1000;
f22aaaa7	417	} else {
088ce2ac GR	418	temp = data->comp[low].temp_c * 1000 +
088ce2ac GR	419	((data->comp[high].temp_c - data->comp[low].temp_c) *
f22aaaa7 DK	420	1000 * ((int)ohm - (int)data->comp[low].ohm)) /
	421	((int)data->comp[high].ohm - (int)data->comp[low].ohm);
	422	}
dbe43a62	423	return temp;
f22aaaa7 DK	424	}
f22aaaa7 DK	425
dbe43a62	426	static int ntc_thermistor_get_ohm(struct ntc_data *data)
f22aaaa7	427	{
088ce2ac	428	int read_uv;
f22aaaa7	429
dbe43a62 GR	430	if (data->pdata->read_ohm)
dbe43a62 GR	431	return data->pdata->read_ohm();
f22aaaa7	432
088ce2ac GR	433	if (data->pdata->read_uv) {
	434	read_uv = data->pdata->read_uv(data->pdata);
	435	if (read_uv < 0)
	436	return read_uv;
	437	return get_ohm_of_thermistor(data, read_uv);
f22aaaa7	438	}
dbe43a62	439	return -EINVAL;
f22aaaa7 DK	440	}
f22aaaa7 DK	441
c08860ff JL	442	static int ntc_read_temp(void dev, long temp)
	443	{
	444	struct ntc_data *data = dev_get_drvdata(dev);
	445	int ohm;
	446
	447	ohm = ntc_thermistor_get_ohm(data);
	448	if (ohm < 0)
	449	return ohm;
	450
	451	*temp = get_temp_mc(data, ohm);
	452
	453	return 0;
	454	}
	455
f22aaaa7 DK	456	static ssize_t ntc_show_name(struct device *dev,
	457	struct device_attribute attr, char buf)
	458	{
	459	struct ntc_data *data = dev_get_drvdata(dev);
	460
	461	return sprintf(buf, "%s\n", data->name);
	462	}
	463
	464	static ssize_t ntc_show_type(struct device *dev,
	465	struct device_attribute attr, char buf)
	466	{
	467	return sprintf(buf, "4\n");
	468	}
	469
	470	static ssize_t ntc_show_temp(struct device *dev,
	471	struct device_attribute attr, char buf)
	472	{
	473	struct ntc_data *data = dev_get_drvdata(dev);
dbe43a62 GR	474	int ohm;
	475
	476	ohm = ntc_thermistor_get_ohm(data);
	477	if (ohm < 0)
	478	return ohm;
f22aaaa7	479
088ce2ac	480	return sprintf(buf, "%d\n", get_temp_mc(data, ohm));
f22aaaa7 DK	481	}
	482
	483	static SENSOR_DEVICE_ATTR(temp1_type, S_IRUGO, ntc_show_type, NULL, 0);
	484	static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, ntc_show_temp, NULL, 0);
	485	static DEVICE_ATTR(name, S_IRUGO, ntc_show_name, NULL);
	486
	487	static struct attribute *ntc_attributes[] = {
	488	&dev_attr_name.attr,
	489	&sensor_dev_attr_temp1_type.dev_attr.attr,
	490	&sensor_dev_attr_temp1_input.dev_attr.attr,
	491	NULL,
	492	};
	493
	494	static const struct attribute_group ntc_attr_group = {
	495	.attrs = ntc_attributes,
	496	};
	497
2251aef6 EV	498	static const struct thermal_zone_of_device_ops ntc_of_thermal_ops = {
	499	.get_temp = ntc_read_temp,
	500	};
	501
6c931ae1	502	static int ntc_thermistor_probe(struct platform_device *pdev)
f22aaaa7	503	{
9e8269de NKC	504	const struct of_device_id *of_id =
	505	of_match_device(of_match_ptr(ntc_match), &pdev->dev);
	506	const struct platform_device_id *pdev_id;
	507	struct ntc_thermistor_platform_data *pdata;
f22aaaa7	508	struct ntc_data *data;
9e8269de NKC	509	int ret;
	510
	511	pdata = ntc_thermistor_parse_dt(pdev);
	512	if (IS_ERR(pdata))
	513	return PTR_ERR(pdata);
	514	else if (pdata == NULL)
a8b3a3a5	515	pdata = dev_get_platdata(&pdev->dev);
f22aaaa7 DK	516
	517	if (!pdata) {
	518	dev_err(&pdev->dev, "No platform init data supplied.\n");
	519	return -ENODEV;
	520	}
	521
	522	/* Either one of the two is required. */
088ce2ac	523	if (!pdata->read_uv && !pdata->read_ohm) {
a7871def	524	dev_err(&pdev->dev,
088ce2ac	525	"Both read_uv and read_ohm missing. Need either one of the two.\n");
f22aaaa7 DK	526	return -EINVAL;
	527	}
	528
088ce2ac	529	if (pdata->read_uv && pdata->read_ohm) {
a7871def	530	dev_warn(&pdev->dev,
088ce2ac GR	531	"Only one of read_uv and read_ohm is needed; ignoring read_uv.\n");
088ce2ac GR	532	pdata->read_uv = NULL;
f22aaaa7 DK	533	}
f22aaaa7 DK	534
088ce2ac	535	if (pdata->read_uv && (pdata->pullup_uv == 0 \|\|
f22aaaa7 DK	536	(pdata->pullup_ohm == 0 && pdata->connect ==
	537	NTC_CONNECTED_GROUND) \|\|
	538	(pdata->pulldown_ohm == 0 && pdata->connect ==
	539	NTC_CONNECTED_POSITIVE) \|\|
	540	(pdata->connect != NTC_CONNECTED_POSITIVE &&
	541	pdata->connect != NTC_CONNECTED_GROUND))) {
a7871def	542	dev_err(&pdev->dev,
088ce2ac	543	"Required data to use read_uv not supplied.\n");
f22aaaa7 DK	544	return -EINVAL;
	545	}
	546
41141e64	547	data = devm_kzalloc(&pdev->dev, sizeof(struct ntc_data), GFP_KERNEL);
f22aaaa7 DK	548	if (!data)
	549	return -ENOMEM;
	550
9e8269de NKC	551	pdev_id = of_id ? of_id->data : platform_get_device_id(pdev);
9e8269de NKC	552
f22aaaa7 DK	553	data->dev = &pdev->dev;
f22aaaa7 DK	554	data->pdata = pdata;
9e8269de	555	strlcpy(data->name, pdev_id->name, sizeof(data->name));
f22aaaa7	556
9e8269de	557	switch (pdev_id->driver_data) {
f22aaaa7 DK	558	case TYPE_NCPXXWB473:
	559	data->comp = ncpXXwb473;
	560	data->n_comp = ARRAY_SIZE(ncpXXwb473);
	561	break;
	562	case TYPE_NCPXXWL333:
	563	data->comp = ncpXXwl333;
	564	data->n_comp = ARRAY_SIZE(ncpXXwl333);
	565	break;
ed67f087 JP	566	case TYPE_B57330V2103:
	567	data->comp = b57330v2103;
	568	data->n_comp = ARRAY_SIZE(b57330v2103);
	569	break;
f22aaaa7 DK	570	default:
f22aaaa7 DK	571	dev_err(&pdev->dev, "Unknown device type: %lu(%s)\n",
9e8269de	572	pdev_id->driver_data, pdev_id->name);
41141e64	573	return -EINVAL;
f22aaaa7 DK	574	}
	575
	576	platform_set_drvdata(pdev, data);
	577
	578	ret = sysfs_create_group(&data->dev->kobj, &ntc_attr_group);
	579	if (ret) {
	580	dev_err(data->dev, "unable to create sysfs files\n");
41141e64	581	return ret;
f22aaaa7 DK	582	}
	583
	584	data->hwmon_dev = hwmon_device_register(data->dev);
425d2476	585	if (IS_ERR(data->hwmon_dev)) {
f22aaaa7	586	dev_err(data->dev, "unable to register as hwmon device.\n");
425d2476	587	ret = PTR_ERR(data->hwmon_dev);
f22aaaa7 DK	588	goto err_after_sysfs;
	589	}
	590
9e8269de	591	dev_info(&pdev->dev, "Thermistor type: %s successfully probed.\n",
93a88ef3	592	pdev_id->name);
9e8269de	593
c08860ff	594	data->tz = thermal_zone_of_sensor_register(data->dev, 0, data->dev,
2251aef6	595	&ntc_of_thermal_ops);
c08860ff JL	596	if (IS_ERR(data->tz)) {
	597	dev_dbg(&pdev->dev, "Failed to register to thermal fw.\n");
	598	data->tz = NULL;
	599	}
	600
f22aaaa7 DK	601	return 0;
	602	err_after_sysfs:
	603	sysfs_remove_group(&data->dev->kobj, &ntc_attr_group);
9e8269de	604	ntc_iio_channel_release(pdata);
f22aaaa7 DK	605	return ret;
	606	}
	607
281dfd0b	608	static int ntc_thermistor_remove(struct platform_device *pdev)
f22aaaa7 DK	609	{
f22aaaa7 DK	610	struct ntc_data *data = platform_get_drvdata(pdev);
9e8269de	611	struct ntc_thermistor_platform_data *pdata = data->pdata;
f22aaaa7 DK	612
	613	hwmon_device_unregister(data->hwmon_dev);
	614	sysfs_remove_group(&data->dev->kobj, &ntc_attr_group);
9e8269de	615	ntc_iio_channel_release(pdata);
f22aaaa7	616
c08860ff JL	617	thermal_zone_of_sensor_unregister(data->dev, data->tz);
c08860ff JL	618
f22aaaa7 DK	619	return 0;
	620	}
	621
f22aaaa7 DK	622	static struct platform_driver ntc_thermistor_driver = {
	623	.driver = {
	624	.name = "ntc-thermistor",
9e8269de	625	.of_match_table = of_match_ptr(ntc_match),
f22aaaa7 DK	626	},
f22aaaa7 DK	627	.probe = ntc_thermistor_probe,
9e5e9b7a	628	.remove = ntc_thermistor_remove,
f22aaaa7 DK	629	.id_table = ntc_thermistor_id,
	630	};
	631
25a236a5	632	module_platform_driver(ntc_thermistor_driver);
f22aaaa7	633
ed67f087	634	MODULE_DESCRIPTION("NTC Thermistor Driver");
f22aaaa7 DK	635	MODULE_AUTHOR("MyungJoo Ham <myungjoo.ham@samsung.com>");
	636	MODULE_LICENSE("GPL");
	637	MODULE_ALIAS("platform:ntc-thermistor");