drivers/hwmon/adt7411.c - kernel/msm-4.19 - Gitiles

 /*
  *  Driver for the ADT7411 (I2C/SPI 8 channel 10 bit ADC & temperature-sensor)
  *
  *  Copyright (C) 2008, 2010 Pengutronix
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License version 2 as
  *  published by the Free Software Foundation.
  *
  *  TODO: SPI, use power-down mode for suspend?, interrupt handling?
  */

 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/err.h>
 #include <linux/mutex.h>
 #include <linux/jiffies.h>
 #include <linux/i2c.h>
 #include <linux/hwmon.h>
 #include <linux/hwmon-sysfs.h>
 #include <linux/slab.h>

 #define ADT7411_REG_INT_TEMP_VDD_LSB		0x03
 #define ADT7411_REG_EXT_TEMP_AIN14_LSB		0x04
 #define ADT7411_REG_VDD_MSB			0x06
 #define ADT7411_REG_INT_TEMP_MSB		0x07
 #define ADT7411_REG_EXT_TEMP_AIN1_MSB		0x08

 #define ADT7411_REG_CFG1			0x18
 #define ADT7411_CFG1_START_MONITOR		(1 << 0)
 #define ADT7411_CFG1_RESERVED_BIT1		(1 << 1)
 #define ADT7411_CFG1_EXT_TDM			(1 << 2)
 #define ADT7411_CFG1_RESERVED_BIT3		(1 << 3)

 #define ADT7411_REG_CFG2			0x19
 #define ADT7411_CFG2_DISABLE_AVG		(1 << 5)

 #define ADT7411_REG_CFG3			0x1a
 #define ADT7411_CFG3_ADC_CLK_225		(1 << 0)
 #define ADT7411_CFG3_RESERVED_BIT1		(1 << 1)
 #define ADT7411_CFG3_RESERVED_BIT2		(1 << 2)
 #define ADT7411_CFG3_RESERVED_BIT3		(1 << 3)
 #define ADT7411_CFG3_REF_VDD			(1 << 4)

 #define ADT7411_REG_DEVICE_ID			0x4d
 #define ADT7411_REG_MANUFACTURER_ID		0x4e

 #define ADT7411_DEVICE_ID			0x2
 #define ADT7411_MANUFACTURER_ID			0x41

 static const unsigned short normal_i2c[] = { 0x48, 0x4a, 0x4b, I2C_CLIENT_END };

 struct adt7411_data {
 	struct mutex device_lock;	/* for "atomic" device accesses */
 	struct mutex update_lock;
 	unsigned long next_update;
 	long vref_cached;
 	struct i2c_client *client;
 	bool use_ext_temp;
 };

 /*
  * When reading a register containing (up to 4) lsb, all associated
  * msb-registers get locked by the hardware. After _one_ of those msb is read,
  * _all_ are unlocked. In order to use this locking correctly, reading lsb/msb
  * is protected here with a mutex, too.
  */
 static int adt7411_read_10_bit(struct i2c_client *client, u8 lsb_reg,
 				u8 msb_reg, u8 lsb_shift)
 {
 	struct adt7411_data *data = i2c_get_clientdata(client);
 	int val, tmp;

 	mutex_lock(&data->device_lock);

 	val = i2c_smbus_read_byte_data(client, lsb_reg);
 	if (val < 0)
 		goto exit_unlock;

 	tmp = (val >> lsb_shift) & 3;
 	val = i2c_smbus_read_byte_data(client, msb_reg);

 	if (val >= 0)
 		val = (val << 2) | tmp;

  exit_unlock:
 	mutex_unlock(&data->device_lock);

 	return val;
 }

 static int adt7411_modify_bit(struct i2c_client *client, u8 reg, u8 bit,
 				bool flag)
 {
 	struct adt7411_data *data = i2c_get_clientdata(client);
 	int ret, val;

 	mutex_lock(&data->device_lock);

 	ret = i2c_smbus_read_byte_data(client, reg);
 	if (ret < 0)
 		goto exit_unlock;

 	if (flag)
 		val = ret | bit;
 	else
 		val = ret & ~bit;

 	ret = i2c_smbus_write_byte_data(client, reg, val);

  exit_unlock:
 	mutex_unlock(&data->device_lock);
 	return ret;
 }

 static ssize_t adt7411_show_bit(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
 	struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(attr);
 	struct adt7411_data *data = dev_get_drvdata(dev);
 	struct i2c_client *client = data->client;
 	int ret = i2c_smbus_read_byte_data(client, attr2->index);

 	return ret < 0 ? ret : sprintf(buf, "%u\n", !!(ret & attr2->nr));
 }

 static ssize_t adt7411_set_bit(struct device *dev,
 			       struct device_attribute *attr, const char *buf,
 			       size_t count)
 {
 	struct sensor_device_attribute_2 *s_attr2 = to_sensor_dev_attr_2(attr);
 	struct adt7411_data *data = dev_get_drvdata(dev);
 	struct i2c_client *client = data->client;
 	int ret;
 	unsigned long flag;

 	ret = kstrtoul(buf, 0, &flag);
 	if (ret || flag > 1)
 		return -EINVAL;

 	ret = adt7411_modify_bit(client, s_attr2->index, s_attr2->nr, flag);

 	/* force update */
 	mutex_lock(&data->update_lock);
 	data->next_update = jiffies;
 	mutex_unlock(&data->update_lock);

 	return ret < 0 ? ret : count;
 }

 #define ADT7411_BIT_ATTR(__name, __reg, __bit) \
 	SENSOR_DEVICE_ATTR_2(__name, S_IRUGO | S_IWUSR, adt7411_show_bit, \
 	adt7411_set_bit, __bit, __reg)

 static ADT7411_BIT_ATTR(no_average, ADT7411_REG_CFG2, ADT7411_CFG2_DISABLE_AVG);
 static ADT7411_BIT_ATTR(fast_sampling, ADT7411_REG_CFG3, ADT7411_CFG3_ADC_CLK_225);
 static ADT7411_BIT_ATTR(adc_ref_vdd, ADT7411_REG_CFG3, ADT7411_CFG3_REF_VDD);

 static struct attribute *adt7411_attrs[] = {
 	&sensor_dev_attr_no_average.dev_attr.attr,
 	&sensor_dev_attr_fast_sampling.dev_attr.attr,
 	&sensor_dev_attr_adc_ref_vdd.dev_attr.attr,
 	NULL
 };
 ATTRIBUTE_GROUPS(adt7411);

 static int adt7411_read_in_vdd(struct device *dev, u32 attr, long *val)
 {
 	struct adt7411_data *data = dev_get_drvdata(dev);
 	struct i2c_client *client = data->client;
 	int ret;

 	switch (attr) {
 	case hwmon_in_input:
 		ret = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB,
 					  ADT7411_REG_VDD_MSB, 2);
 		if (ret < 0)
 			return ret;
 		*val = ret * 7000 / 1024;
 		return 0;
 	default:
 		return -EOPNOTSUPP;
 	}
 }

 static int adt7411_read_in_chan(struct device *dev, u32 attr, int channel,
 				long *val)
 {
 	struct adt7411_data *data = dev_get_drvdata(dev);
 	struct i2c_client *client = data->client;

 	int ret;
 	int lsb_reg, lsb_shift;
 	int nr = channel - 1;

 	mutex_lock(&data->update_lock);
 	if (time_after_eq(jiffies, data->next_update)) {
 		ret = i2c_smbus_read_byte_data(client, ADT7411_REG_CFG3);
 		if (ret < 0)
 			goto exit_unlock;

 		if (ret & ADT7411_CFG3_REF_VDD) {
 			ret = adt7411_read_in_vdd(dev, hwmon_in_input,
 						  &data->vref_cached);
 			if (ret < 0)
 				goto exit_unlock;
 		} else {
 			data->vref_cached = 2250;
 		}

 		data->next_update = jiffies + HZ;
 	}

 	switch (attr) {
 	case hwmon_in_input:
 		lsb_reg = ADT7411_REG_EXT_TEMP_AIN14_LSB + (nr >> 2);
 		lsb_shift = 2 * (nr & 0x03);
 		ret = adt7411_read_10_bit(client, lsb_reg,
 					  ADT7411_REG_EXT_TEMP_AIN1_MSB + nr,
 					  lsb_shift);
 		if (ret < 0)
 			goto exit_unlock;
 		*val = ret * data->vref_cached / 1024;
 		ret = 0;
 		break;
 	default:
 		ret = -EOPNOTSUPP;
 		break;
 	}
  exit_unlock:
 	mutex_unlock(&data->update_lock);
 	return ret;
 }

 static int adt7411_read_in(struct device *dev, u32 attr, int channel,
 			   long *val)
 {
 	if (channel == 0)
 		return adt7411_read_in_vdd(dev, attr, val);
 	else
 		return adt7411_read_in_chan(dev, attr, channel, val);
 }

 static int adt7411_read_temp(struct device *dev, u32 attr, int channel,
 			     long *val)
 {
 	struct adt7411_data *data = dev_get_drvdata(dev);
 	struct i2c_client *client = data->client;
 	int ret, regl, regh;

 	switch (attr) {
 	case hwmon_temp_input:
 		regl = channel ? ADT7411_REG_EXT_TEMP_AIN14_LSB :
 				 ADT7411_REG_INT_TEMP_VDD_LSB;
 		regh = channel ? ADT7411_REG_EXT_TEMP_AIN1_MSB :
 				 ADT7411_REG_INT_TEMP_MSB;
 		ret = adt7411_read_10_bit(client, regl, regh, 0);
 		if (ret < 0)
 			return ret;
 		ret = ret & 0x200 ? ret - 0x400 : ret; /* 10 bit signed */
 		*val = ret * 250;
 		return 0;
 	default:
 		return -EOPNOTSUPP;
 	}
 }

 static int adt7411_read(struct device *dev, enum hwmon_sensor_types type,
 			u32 attr, int channel, long *val)
 {
 	switch (type) {
 	case hwmon_in:
 		return adt7411_read_in(dev, attr, channel, val);
 	case hwmon_temp:
 		return adt7411_read_temp(dev, attr, channel, val);
 	default:
 		return -EOPNOTSUPP;
 	}
 }

 static umode_t adt7411_is_visible(const void *_data,
 				  enum hwmon_sensor_types type,
 				  u32 attr, int channel)
 {
 	const struct adt7411_data *data = _data;

 	switch (type) {
 	case hwmon_in:
 		if (channel > 0 && channel < 3)
 			return data->use_ext_temp ? 0 : S_IRUGO;
 		else
 			return S_IRUGO;
 	case hwmon_temp:
 		if (channel == 1)
 			return data->use_ext_temp ? S_IRUGO : 0;
 		else
 			return S_IRUGO;
 	default:
 		return 0;
 	}
 }

 static int adt7411_detect(struct i2c_client *client,
 			  struct i2c_board_info *info)
 {
 	int val;

 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
 		return -ENODEV;

 	val = i2c_smbus_read_byte_data(client, ADT7411_REG_MANUFACTURER_ID);
 	if (val < 0 || val != ADT7411_MANUFACTURER_ID) {
 		dev_dbg(&client->dev,
 			"Wrong manufacturer ID. Got %d, expected %d\n",
 			val, ADT7411_MANUFACTURER_ID);
 		return -ENODEV;
 	}

 	val = i2c_smbus_read_byte_data(client, ADT7411_REG_DEVICE_ID);
 	if (val < 0 || val != ADT7411_DEVICE_ID) {
 		dev_dbg(&client->dev,
 			"Wrong device ID. Got %d, expected %d\n",
 			val, ADT7411_DEVICE_ID);
 		return -ENODEV;
 	}

 	strlcpy(info->type, "adt7411", I2C_NAME_SIZE);

 	return 0;
 }

 static int adt7411_init_device(struct adt7411_data *data)
 {
 	int ret;
 	u8 val;

 	ret = i2c_smbus_read_byte_data(data->client, ADT7411_REG_CFG3);
 	if (ret < 0)
 		return ret;

 	/*
 	 * We must only write zero to bit 1 and bit 2 and only one to bit 3
 	 * according to the datasheet.
 	 */
 	val = ret;
 	val &= ~(ADT7411_CFG3_RESERVED_BIT1 | ADT7411_CFG3_RESERVED_BIT2);
 	val |= ADT7411_CFG3_RESERVED_BIT3;

 	ret = i2c_smbus_write_byte_data(data->client, ADT7411_REG_CFG3, val);
 	if (ret < 0)
 		return ret;

 	ret = i2c_smbus_read_byte_data(data->client, ADT7411_REG_CFG1);
 	if (ret < 0)
 		return ret;

 	data->use_ext_temp = ret & ADT7411_CFG1_EXT_TDM;

 	/*
 	 * We must only write zero to bit 1 and only one to bit 3 according to
 	 * the datasheet.
 	 */
 	val = ret;
 	val &= ~ADT7411_CFG1_RESERVED_BIT1;
 	val |= ADT7411_CFG1_RESERVED_BIT3;

 	/* enable monitoring */
 	val |= ADT7411_CFG1_START_MONITOR;

 	return i2c_smbus_write_byte_data(data->client, ADT7411_REG_CFG1, val);
 }

 static const u32 adt7411_in_config[] = {
 	HWMON_I_INPUT,
 	HWMON_I_INPUT,
 	HWMON_I_INPUT,
 	HWMON_I_INPUT,
 	HWMON_I_INPUT,
 	HWMON_I_INPUT,
 	HWMON_I_INPUT,
 	HWMON_I_INPUT,
 	HWMON_I_INPUT,
 	0
 };

 static const struct hwmon_channel_info adt7411_in = {
 	.type = hwmon_in,
 	.config = adt7411_in_config,
 };

 static const u32 adt7411_temp_config[] = {
 	HWMON_T_INPUT,
 	HWMON_T_INPUT,
 	0
 };

 static const struct hwmon_channel_info adt7411_temp = {
 	.type = hwmon_temp,
 	.config = adt7411_temp_config,
 };

 static const struct hwmon_channel_info *adt7411_info[] = {
 	&adt7411_in,
 	&adt7411_temp,
 	NULL
 };

 static const struct hwmon_ops adt7411_hwmon_ops = {
 	.is_visible = adt7411_is_visible,
 	.read = adt7411_read,
 };

 static const struct hwmon_chip_info adt7411_chip_info = {
 	.ops = &adt7411_hwmon_ops,
 	.info = adt7411_info,
 };

 static int adt7411_probe(struct i2c_client *client,
 				   const struct i2c_device_id *id)
 {
 	struct device *dev = &client->dev;
 	struct adt7411_data *data;
 	struct device *hwmon_dev;
 	int ret;

 	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
 	if (!data)
 		return -ENOMEM;

 	i2c_set_clientdata(client, data);
 	data->client = client;
 	mutex_init(&data->device_lock);
 	mutex_init(&data->update_lock);

 	ret = adt7411_init_device(data);
 	if (ret < 0)
 		return ret;

 	/* force update on first occasion */
 	data->next_update = jiffies;

 	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
 							 data,
 							 &adt7411_chip_info,
 							 adt7411_groups);
 	return PTR_ERR_OR_ZERO(hwmon_dev);
 }

 static const struct i2c_device_id adt7411_id[] = {
 	{ "adt7411", 0 },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, adt7411_id);

 static struct i2c_driver adt7411_driver = {
 	.driver		= {
 		.name		= "adt7411",
 	},
 	.probe  = adt7411_probe,
 	.id_table = adt7411_id,
 	.detect = adt7411_detect,
 	.address_list = normal_i2c,
 	.class = I2C_CLASS_HWMON,
 };

 module_i2c_driver(adt7411_driver);

 MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de> and "
 	"Wolfram Sang <w.sang@pengutronix.de>");
 MODULE_DESCRIPTION("ADT7411 driver");
 MODULE_LICENSE("GPL v2");
	/*
	* Driver for the ADT7411 (I2C/SPI 8 channel 10 bit ADC & temperature-sensor)
	*
	* Copyright (C) 2008, 2010 Pengutronix
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License version 2 as
	* published by the Free Software Foundation.
	*
	* TODO: SPI, use power-down mode for suspend?, interrupt handling?
	*/

	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/init.h>
	#include <linux/err.h>
	#include <linux/mutex.h>
	#include <linux/jiffies.h>
	#include <linux/i2c.h>
	#include <linux/hwmon.h>
	#include <linux/hwmon-sysfs.h>
	#include <linux/slab.h>

	#define ADT7411_REG_INT_TEMP_VDD_LSB 0x03
	#define ADT7411_REG_EXT_TEMP_AIN14_LSB 0x04
	#define ADT7411_REG_VDD_MSB 0x06
	#define ADT7411_REG_INT_TEMP_MSB 0x07
	#define ADT7411_REG_EXT_TEMP_AIN1_MSB 0x08

	#define ADT7411_REG_CFG1 0x18
	#define ADT7411_CFG1_START_MONITOR (1 << 0)
	#define ADT7411_CFG1_RESERVED_BIT1 (1 << 1)
	#define ADT7411_CFG1_EXT_TDM (1 << 2)
	#define ADT7411_CFG1_RESERVED_BIT3 (1 << 3)

	#define ADT7411_REG_CFG2 0x19
	#define ADT7411_CFG2_DISABLE_AVG (1 << 5)

	#define ADT7411_REG_CFG3 0x1a
	#define ADT7411_CFG3_ADC_CLK_225 (1 << 0)
	#define ADT7411_CFG3_RESERVED_BIT1 (1 << 1)
	#define ADT7411_CFG3_RESERVED_BIT2 (1 << 2)
	#define ADT7411_CFG3_RESERVED_BIT3 (1 << 3)
	#define ADT7411_CFG3_REF_VDD (1 << 4)

	#define ADT7411_REG_DEVICE_ID 0x4d
	#define ADT7411_REG_MANUFACTURER_ID 0x4e

	#define ADT7411_DEVICE_ID 0x2
	#define ADT7411_MANUFACTURER_ID 0x41

	static const unsigned short normal_i2c[] = { 0x48, 0x4a, 0x4b, I2C_CLIENT_END };

	struct adt7411_data {
	struct mutex device_lock; /* for "atomic" device accesses */
	struct mutex update_lock;
	unsigned long next_update;
	long vref_cached;
	struct i2c_client *client;
	bool use_ext_temp;
	};

	/*
	* When reading a register containing (up to 4) lsb, all associated
	* msb-registers get locked by the hardware. After _one_ of those msb is read,
	* _all_ are unlocked. In order to use this locking correctly, reading lsb/msb
	* is protected here with a mutex, too.
	*/
	static int adt7411_read_10_bit(struct i2c_client *client, u8 lsb_reg,
	u8 msb_reg, u8 lsb_shift)
	{
	struct adt7411_data *data = i2c_get_clientdata(client);
	int val, tmp;

	mutex_lock(&data->device_lock);

	val = i2c_smbus_read_byte_data(client, lsb_reg);
	if (val < 0)
	goto exit_unlock;

	tmp = (val >> lsb_shift) & 3;
	val = i2c_smbus_read_byte_data(client, msb_reg);

	if (val >= 0)
	val = (val << 2) \| tmp;

	exit_unlock:
	mutex_unlock(&data->device_lock);

	return val;
	}

	static int adt7411_modify_bit(struct i2c_client *client, u8 reg, u8 bit,
	bool flag)
	{
	struct adt7411_data *data = i2c_get_clientdata(client);
	int ret, val;

	mutex_lock(&data->device_lock);

	ret = i2c_smbus_read_byte_data(client, reg);
	if (ret < 0)
	goto exit_unlock;

	if (flag)
	val = ret \| bit;
	else
	val = ret & ~bit;

	ret = i2c_smbus_write_byte_data(client, reg, val);

	exit_unlock:
	mutex_unlock(&data->device_lock);
	return ret;
	}

	static ssize_t adt7411_show_bit(struct device *dev,
	struct device_attribute attr, char buf)
	{
	struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(attr);
	struct adt7411_data *data = dev_get_drvdata(dev);
	struct i2c_client *client = data->client;
	int ret = i2c_smbus_read_byte_data(client, attr2->index);

	return ret < 0 ? ret : sprintf(buf, "%u\n", !!(ret & attr2->nr));
	}

	static ssize_t adt7411_set_bit(struct device *dev,
	struct device_attribute attr, const char buf,
	size_t count)
	{
	struct sensor_device_attribute_2 *s_attr2 = to_sensor_dev_attr_2(attr);
	struct adt7411_data *data = dev_get_drvdata(dev);
	struct i2c_client *client = data->client;
	int ret;
	unsigned long flag;

	ret = kstrtoul(buf, 0, &flag);
	if (ret \|\| flag > 1)
	return -EINVAL;

	ret = adt7411_modify_bit(client, s_attr2->index, s_attr2->nr, flag);

	/* force update */
	mutex_lock(&data->update_lock);
	data->next_update = jiffies;
	mutex_unlock(&data->update_lock);

	return ret < 0 ? ret : count;
	}

	#define ADT7411_BIT_ATTR(__name, __reg, __bit) \
	SENSOR_DEVICE_ATTR_2(__name, S_IRUGO \| S_IWUSR, adt7411_show_bit, \
	adt7411_set_bit, __bit, __reg)

	static ADT7411_BIT_ATTR(no_average, ADT7411_REG_CFG2, ADT7411_CFG2_DISABLE_AVG);
	static ADT7411_BIT_ATTR(fast_sampling, ADT7411_REG_CFG3, ADT7411_CFG3_ADC_CLK_225);
	static ADT7411_BIT_ATTR(adc_ref_vdd, ADT7411_REG_CFG3, ADT7411_CFG3_REF_VDD);

	static struct attribute *adt7411_attrs[] = {
	&sensor_dev_attr_no_average.dev_attr.attr,
	&sensor_dev_attr_fast_sampling.dev_attr.attr,
	&sensor_dev_attr_adc_ref_vdd.dev_attr.attr,
	NULL
	};
	ATTRIBUTE_GROUPS(adt7411);

	static int adt7411_read_in_vdd(struct device dev, u32 attr, long val)
	{
	struct adt7411_data *data = dev_get_drvdata(dev);
	struct i2c_client *client = data->client;
	int ret;

	switch (attr) {
	case hwmon_in_input:
	ret = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB,
	ADT7411_REG_VDD_MSB, 2);
	if (ret < 0)
	return ret;
	val = ret 7000 / 1024;
	return 0;
	default:
	return -EOPNOTSUPP;
	}
	}

	static int adt7411_read_in_chan(struct device *dev, u32 attr, int channel,
	long *val)
	{
	struct adt7411_data *data = dev_get_drvdata(dev);
	struct i2c_client *client = data->client;

	int ret;
	int lsb_reg, lsb_shift;
	int nr = channel - 1;

	mutex_lock(&data->update_lock);
	if (time_after_eq(jiffies, data->next_update)) {
	ret = i2c_smbus_read_byte_data(client, ADT7411_REG_CFG3);
	if (ret < 0)
	goto exit_unlock;

	if (ret & ADT7411_CFG3_REF_VDD) {
	ret = adt7411_read_in_vdd(dev, hwmon_in_input,
	&data->vref_cached);
	if (ret < 0)
	goto exit_unlock;
	} else {
	data->vref_cached = 2250;
	}

	data->next_update = jiffies + HZ;
	}

	switch (attr) {
	case hwmon_in_input:
	lsb_reg = ADT7411_REG_EXT_TEMP_AIN14_LSB + (nr >> 2);
	lsb_shift = 2 * (nr & 0x03);
	ret = adt7411_read_10_bit(client, lsb_reg,
	ADT7411_REG_EXT_TEMP_AIN1_MSB + nr,
	lsb_shift);
	if (ret < 0)
	goto exit_unlock;
	val = ret data->vref_cached / 1024;
	ret = 0;
	break;
	default:
	ret = -EOPNOTSUPP;
	break;
	}
	exit_unlock:
	mutex_unlock(&data->update_lock);
	return ret;
	}

	static int adt7411_read_in(struct device *dev, u32 attr, int channel,
	long *val)
	{
	if (channel == 0)
	return adt7411_read_in_vdd(dev, attr, val);
	else
	return adt7411_read_in_chan(dev, attr, channel, val);
	}

	static int adt7411_read_temp(struct device *dev, u32 attr, int channel,
	long *val)
	{
	struct adt7411_data *data = dev_get_drvdata(dev);
	struct i2c_client *client = data->client;
	int ret, regl, regh;

	switch (attr) {
	case hwmon_temp_input:
	regl = channel ? ADT7411_REG_EXT_TEMP_AIN14_LSB :
	ADT7411_REG_INT_TEMP_VDD_LSB;
	regh = channel ? ADT7411_REG_EXT_TEMP_AIN1_MSB :
	ADT7411_REG_INT_TEMP_MSB;
	ret = adt7411_read_10_bit(client, regl, regh, 0);
	if (ret < 0)
	return ret;
	ret = ret & 0x200 ? ret - 0x400 : ret; /* 10 bit signed */
	val = ret 250;
	return 0;
	default:
	return -EOPNOTSUPP;
	}
	}

	static int adt7411_read(struct device *dev, enum hwmon_sensor_types type,
	u32 attr, int channel, long *val)
	{
	switch (type) {
	case hwmon_in:
	return adt7411_read_in(dev, attr, channel, val);
	case hwmon_temp:
	return adt7411_read_temp(dev, attr, channel, val);
	default:
	return -EOPNOTSUPP;
	}
	}

	static umode_t adt7411_is_visible(const void *_data,
	enum hwmon_sensor_types type,
	u32 attr, int channel)
	{
	const struct adt7411_data *data = _data;

	switch (type) {
	case hwmon_in:
	if (channel > 0 && channel < 3)
	return data->use_ext_temp ? 0 : S_IRUGO;
	else
	return S_IRUGO;
	case hwmon_temp:
	if (channel == 1)
	return data->use_ext_temp ? S_IRUGO : 0;
	else
	return S_IRUGO;
	default:
	return 0;
	}
	}

	static int adt7411_detect(struct i2c_client *client,
	struct i2c_board_info *info)
	{
	int val;

	if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
	return -ENODEV;

	val = i2c_smbus_read_byte_data(client, ADT7411_REG_MANUFACTURER_ID);
	if (val < 0 \|\| val != ADT7411_MANUFACTURER_ID) {
	dev_dbg(&client->dev,
	"Wrong manufacturer ID. Got %d, expected %d\n",
	val, ADT7411_MANUFACTURER_ID);
	return -ENODEV;
	}

	val = i2c_smbus_read_byte_data(client, ADT7411_REG_DEVICE_ID);
	if (val < 0 \|\| val != ADT7411_DEVICE_ID) {
	dev_dbg(&client->dev,
	"Wrong device ID. Got %d, expected %d\n",
	val, ADT7411_DEVICE_ID);
	return -ENODEV;
	}

	strlcpy(info->type, "adt7411", I2C_NAME_SIZE);

	return 0;
	}

	static int adt7411_init_device(struct adt7411_data *data)
	{
	int ret;
	u8 val;

	ret = i2c_smbus_read_byte_data(data->client, ADT7411_REG_CFG3);
	if (ret < 0)
	return ret;

	/*
	* We must only write zero to bit 1 and bit 2 and only one to bit 3
	* according to the datasheet.
	*/
	val = ret;
	val &= ~(ADT7411_CFG3_RESERVED_BIT1 \| ADT7411_CFG3_RESERVED_BIT2);
	val \|= ADT7411_CFG3_RESERVED_BIT3;

	ret = i2c_smbus_write_byte_data(data->client, ADT7411_REG_CFG3, val);
	if (ret < 0)
	return ret;

	ret = i2c_smbus_read_byte_data(data->client, ADT7411_REG_CFG1);
	if (ret < 0)
	return ret;

	data->use_ext_temp = ret & ADT7411_CFG1_EXT_TDM;

	/*
	* We must only write zero to bit 1 and only one to bit 3 according to
	* the datasheet.
	*/
	val = ret;
	val &= ~ADT7411_CFG1_RESERVED_BIT1;
	val \|= ADT7411_CFG1_RESERVED_BIT3;

	/* enable monitoring */
	val \|= ADT7411_CFG1_START_MONITOR;

	return i2c_smbus_write_byte_data(data->client, ADT7411_REG_CFG1, val);
	}

	static const u32 adt7411_in_config[] = {
	HWMON_I_INPUT,
	HWMON_I_INPUT,
	HWMON_I_INPUT,
	HWMON_I_INPUT,
	HWMON_I_INPUT,
	HWMON_I_INPUT,
	HWMON_I_INPUT,
	HWMON_I_INPUT,
	HWMON_I_INPUT,
	0
	};

	static const struct hwmon_channel_info adt7411_in = {
	.type = hwmon_in,
	.config = adt7411_in_config,
	};

	static const u32 adt7411_temp_config[] = {
	HWMON_T_INPUT,
	HWMON_T_INPUT,
	0
	};

	static const struct hwmon_channel_info adt7411_temp = {
	.type = hwmon_temp,
	.config = adt7411_temp_config,
	};

	static const struct hwmon_channel_info *adt7411_info[] = {
	&adt7411_in,
	&adt7411_temp,
	NULL
	};

	static const struct hwmon_ops adt7411_hwmon_ops = {
	.is_visible = adt7411_is_visible,
	.read = adt7411_read,
	};

	static const struct hwmon_chip_info adt7411_chip_info = {
	.ops = &adt7411_hwmon_ops,
	.info = adt7411_info,
	};

	static int adt7411_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
	{
	struct device *dev = &client->dev;
	struct adt7411_data *data;
	struct device *hwmon_dev;
	int ret;

	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
	if (!data)
	return -ENOMEM;

	i2c_set_clientdata(client, data);
	data->client = client;
	mutex_init(&data->device_lock);
	mutex_init(&data->update_lock);

	ret = adt7411_init_device(data);
	if (ret < 0)
	return ret;

	/* force update on first occasion */
	data->next_update = jiffies;

	hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
	data,
	&adt7411_chip_info,
	adt7411_groups);
	return PTR_ERR_OR_ZERO(hwmon_dev);
	}

	static const struct i2c_device_id adt7411_id[] = {
	{ "adt7411", 0 },
	{ }
	};
	MODULE_DEVICE_TABLE(i2c, adt7411_id);

	static struct i2c_driver adt7411_driver = {
	.driver = {
	.name = "adt7411",
	},
	.probe = adt7411_probe,
	.id_table = adt7411_id,
	.detect = adt7411_detect,
	.address_list = normal_i2c,
	.class = I2C_CLASS_HWMON,
	};

	module_i2c_driver(adt7411_driver);

	MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de> and "
	"Wolfram Sang <w.sang@pengutronix.de>");
	MODULE_DESCRIPTION("ADT7411 driver");
	MODULE_LICENSE("GPL v2");