drivers/hwmon/powr1220.c - linux - Git at Google

 /*
  * powr1220.c - Driver for the Lattice POWR1220 programmable power supply
  * and monitor. Users can read all ADC inputs along with their labels
  * using the sysfs nodes.
  *
  * Copyright (c) 2014 Echo360 http://www.echo360.com
  * Scott Kanowitz <skanowitz@echo360.com> <scott.kanowitz@gmail.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.
  */

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

 #define ADC_STEP_MV			2
 #define ADC_MAX_LOW_MEASUREMENT_MV	2000

 enum powr1220_regs {
 	VMON_STATUS0,
 	VMON_STATUS1,
 	VMON_STATUS2,
 	OUTPUT_STATUS0,
 	OUTPUT_STATUS1,
 	OUTPUT_STATUS2,
 	INPUT_STATUS,
 	ADC_VALUE_LOW,
 	ADC_VALUE_HIGH,
 	ADC_MUX,
 	UES_BYTE0,
 	UES_BYTE1,
 	UES_BYTE2,
 	UES_BYTE3,
 	GP_OUTPUT1,
 	GP_OUTPUT2,
 	GP_OUTPUT3,
 	INPUT_VALUE,
 	RESET,
 	TRIM1_TRIM,
 	TRIM2_TRIM,
 	TRIM3_TRIM,
 	TRIM4_TRIM,
 	TRIM5_TRIM,
 	TRIM6_TRIM,
 	TRIM7_TRIM,
 	TRIM8_TRIM,
 	MAX_POWR1220_REGS
 };

 enum powr1220_adc_values {
 	VMON1,
 	VMON2,
 	VMON3,
 	VMON4,
 	VMON5,
 	VMON6,
 	VMON7,
 	VMON8,
 	VMON9,
 	VMON10,
 	VMON11,
 	VMON12,
 	VCCA,
 	VCCINP,
 	MAX_POWR1220_ADC_VALUES
 };

 struct powr1220_data {
 	struct i2c_client *client;
 	struct mutex update_lock;
 	bool adc_valid[MAX_POWR1220_ADC_VALUES];
 	 /* the next value is in jiffies */
 	unsigned long adc_last_updated[MAX_POWR1220_ADC_VALUES];

 	/* values */
 	int adc_maxes[MAX_POWR1220_ADC_VALUES];
 	int adc_values[MAX_POWR1220_ADC_VALUES];
 };

 static const char * const input_names[] = {
 	[VMON1]    = "vmon1",
 	[VMON2]    = "vmon2",
 	[VMON3]    = "vmon3",
 	[VMON4]    = "vmon4",
 	[VMON5]    = "vmon5",
 	[VMON6]    = "vmon6",
 	[VMON7]    = "vmon7",
 	[VMON8]    = "vmon8",
 	[VMON9]    = "vmon9",
 	[VMON10]   = "vmon10",
 	[VMON11]   = "vmon11",
 	[VMON12]   = "vmon12",
 	[VCCA]     = "vcca",
 	[VCCINP]   = "vccinp",
 };

 /* Reads the specified ADC channel */
 static int powr1220_read_adc(struct device *dev, int ch_num)
 {
 	struct powr1220_data *data = dev_get_drvdata(dev);
 	int reading;
 	int result;
 	int adc_range = 0;

 	mutex_lock(&data->update_lock);

 	if (time_after(jiffies, data->adc_last_updated[ch_num] + HZ) ||
 			!data->adc_valid[ch_num]) {
 		/*
 		 * figure out if we need to use the attenuator for
 		 * high inputs or inputs that we don't yet have a measurement
 		 * for. We dynamically set the attenuator depending on the
 		 * max reading.
 		 */
 		if (data->adc_maxes[ch_num] > ADC_MAX_LOW_MEASUREMENT_MV ||
 				data->adc_maxes[ch_num] == 0)
 			adc_range = 1 << 4;

 		/* set the attenuator and mux */
 		result = i2c_smbus_write_byte_data(data->client, ADC_MUX,
 				adc_range | ch_num);
 		if (result)
 			goto exit;

 		/*
 		 * wait at least Tconvert time (200 us) for the
 		 * conversion to complete
 		 */
 		udelay(200);

 		/* get the ADC reading */
 		result = i2c_smbus_read_byte_data(data->client, ADC_VALUE_LOW);
 		if (result < 0)
 			goto exit;

 		reading = result >> 4;

 		/* get the upper half of the reading */
 		result = i2c_smbus_read_byte_data(data->client, ADC_VALUE_HIGH);
 		if (result < 0)
 			goto exit;

 		reading |= result << 4;

 		/* now convert the reading to a voltage */
 		reading *= ADC_STEP_MV;
 		data->adc_values[ch_num] = reading;
 		data->adc_valid[ch_num] = true;
 		data->adc_last_updated[ch_num] = jiffies;
 		result = reading;

 		if (reading > data->adc_maxes[ch_num])
 			data->adc_maxes[ch_num] = reading;
 	} else {
 		result = data->adc_values[ch_num];
 	}

 exit:
 	mutex_unlock(&data->update_lock);

 	return result;
 }

 /* Shows the voltage associated with the specified ADC channel */
 static ssize_t powr1220_voltage_show(struct device *dev,
 				     struct device_attribute *dev_attr,
 				     char *buf)
 {
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
 	int adc_val = powr1220_read_adc(dev, attr->index);

 	if (adc_val < 0)
 		return adc_val;

 	return sprintf(buf, "%d\n", adc_val);
 }

 /* Shows the maximum setting associated with the specified ADC channel */
 static ssize_t powr1220_max_show(struct device *dev,
 				 struct device_attribute *dev_attr, char *buf)
 {
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
 	struct powr1220_data *data = dev_get_drvdata(dev);

 	return sprintf(buf, "%d\n", data->adc_maxes[attr->index]);
 }

 /* Shows the label associated with the specified ADC channel */
 static ssize_t powr1220_label_show(struct device *dev,
 				   struct device_attribute *dev_attr,
 				   char *buf)
 {
 	struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);

 	return sprintf(buf, "%s\n", input_names[attr->index]);
 }

 static SENSOR_DEVICE_ATTR_RO(in0_input, powr1220_voltage, VMON1);
 static SENSOR_DEVICE_ATTR_RO(in1_input, powr1220_voltage, VMON2);
 static SENSOR_DEVICE_ATTR_RO(in2_input, powr1220_voltage, VMON3);
 static SENSOR_DEVICE_ATTR_RO(in3_input, powr1220_voltage, VMON4);
 static SENSOR_DEVICE_ATTR_RO(in4_input, powr1220_voltage, VMON5);
 static SENSOR_DEVICE_ATTR_RO(in5_input, powr1220_voltage, VMON6);
 static SENSOR_DEVICE_ATTR_RO(in6_input, powr1220_voltage, VMON7);
 static SENSOR_DEVICE_ATTR_RO(in7_input, powr1220_voltage, VMON8);
 static SENSOR_DEVICE_ATTR_RO(in8_input, powr1220_voltage, VMON9);
 static SENSOR_DEVICE_ATTR_RO(in9_input, powr1220_voltage, VMON10);
 static SENSOR_DEVICE_ATTR_RO(in10_input, powr1220_voltage, VMON11);
 static SENSOR_DEVICE_ATTR_RO(in11_input, powr1220_voltage, VMON12);
 static SENSOR_DEVICE_ATTR_RO(in12_input, powr1220_voltage, VCCA);
 static SENSOR_DEVICE_ATTR_RO(in13_input, powr1220_voltage, VCCINP);

 static SENSOR_DEVICE_ATTR_RO(in0_highest, powr1220_max, VMON1);
 static SENSOR_DEVICE_ATTR_RO(in1_highest, powr1220_max, VMON2);
 static SENSOR_DEVICE_ATTR_RO(in2_highest, powr1220_max, VMON3);
 static SENSOR_DEVICE_ATTR_RO(in3_highest, powr1220_max, VMON4);
 static SENSOR_DEVICE_ATTR_RO(in4_highest, powr1220_max, VMON5);
 static SENSOR_DEVICE_ATTR_RO(in5_highest, powr1220_max, VMON6);
 static SENSOR_DEVICE_ATTR_RO(in6_highest, powr1220_max, VMON7);
 static SENSOR_DEVICE_ATTR_RO(in7_highest, powr1220_max, VMON8);
 static SENSOR_DEVICE_ATTR_RO(in8_highest, powr1220_max, VMON9);
 static SENSOR_DEVICE_ATTR_RO(in9_highest, powr1220_max, VMON10);
 static SENSOR_DEVICE_ATTR_RO(in10_highest, powr1220_max, VMON11);
 static SENSOR_DEVICE_ATTR_RO(in11_highest, powr1220_max, VMON12);
 static SENSOR_DEVICE_ATTR_RO(in12_highest, powr1220_max, VCCA);
 static SENSOR_DEVICE_ATTR_RO(in13_highest, powr1220_max, VCCINP);

 static SENSOR_DEVICE_ATTR_RO(in0_label, powr1220_label, VMON1);
 static SENSOR_DEVICE_ATTR_RO(in1_label, powr1220_label, VMON2);
 static SENSOR_DEVICE_ATTR_RO(in2_label, powr1220_label, VMON3);
 static SENSOR_DEVICE_ATTR_RO(in3_label, powr1220_label, VMON4);
 static SENSOR_DEVICE_ATTR_RO(in4_label, powr1220_label, VMON5);
 static SENSOR_DEVICE_ATTR_RO(in5_label, powr1220_label, VMON6);
 static SENSOR_DEVICE_ATTR_RO(in6_label, powr1220_label, VMON7);
 static SENSOR_DEVICE_ATTR_RO(in7_label, powr1220_label, VMON8);
 static SENSOR_DEVICE_ATTR_RO(in8_label, powr1220_label, VMON9);
 static SENSOR_DEVICE_ATTR_RO(in9_label, powr1220_label, VMON10);
 static SENSOR_DEVICE_ATTR_RO(in10_label, powr1220_label, VMON11);
 static SENSOR_DEVICE_ATTR_RO(in11_label, powr1220_label, VMON12);
 static SENSOR_DEVICE_ATTR_RO(in12_label, powr1220_label, VCCA);
 static SENSOR_DEVICE_ATTR_RO(in13_label, powr1220_label, VCCINP);

 static struct attribute *powr1220_attrs[] = {
 	&sensor_dev_attr_in0_input.dev_attr.attr,
 	&sensor_dev_attr_in1_input.dev_attr.attr,
 	&sensor_dev_attr_in2_input.dev_attr.attr,
 	&sensor_dev_attr_in3_input.dev_attr.attr,
 	&sensor_dev_attr_in4_input.dev_attr.attr,
 	&sensor_dev_attr_in5_input.dev_attr.attr,
 	&sensor_dev_attr_in6_input.dev_attr.attr,
 	&sensor_dev_attr_in7_input.dev_attr.attr,
 	&sensor_dev_attr_in8_input.dev_attr.attr,
 	&sensor_dev_attr_in9_input.dev_attr.attr,
 	&sensor_dev_attr_in10_input.dev_attr.attr,
 	&sensor_dev_attr_in11_input.dev_attr.attr,
 	&sensor_dev_attr_in12_input.dev_attr.attr,
 	&sensor_dev_attr_in13_input.dev_attr.attr,

 	&sensor_dev_attr_in0_highest.dev_attr.attr,
 	&sensor_dev_attr_in1_highest.dev_attr.attr,
 	&sensor_dev_attr_in2_highest.dev_attr.attr,
 	&sensor_dev_attr_in3_highest.dev_attr.attr,
 	&sensor_dev_attr_in4_highest.dev_attr.attr,
 	&sensor_dev_attr_in5_highest.dev_attr.attr,
 	&sensor_dev_attr_in6_highest.dev_attr.attr,
 	&sensor_dev_attr_in7_highest.dev_attr.attr,
 	&sensor_dev_attr_in8_highest.dev_attr.attr,
 	&sensor_dev_attr_in9_highest.dev_attr.attr,
 	&sensor_dev_attr_in10_highest.dev_attr.attr,
 	&sensor_dev_attr_in11_highest.dev_attr.attr,
 	&sensor_dev_attr_in12_highest.dev_attr.attr,
 	&sensor_dev_attr_in13_highest.dev_attr.attr,

 	&sensor_dev_attr_in0_label.dev_attr.attr,
 	&sensor_dev_attr_in1_label.dev_attr.attr,
 	&sensor_dev_attr_in2_label.dev_attr.attr,
 	&sensor_dev_attr_in3_label.dev_attr.attr,
 	&sensor_dev_attr_in4_label.dev_attr.attr,
 	&sensor_dev_attr_in5_label.dev_attr.attr,
 	&sensor_dev_attr_in6_label.dev_attr.attr,
 	&sensor_dev_attr_in7_label.dev_attr.attr,
 	&sensor_dev_attr_in8_label.dev_attr.attr,
 	&sensor_dev_attr_in9_label.dev_attr.attr,
 	&sensor_dev_attr_in10_label.dev_attr.attr,
 	&sensor_dev_attr_in11_label.dev_attr.attr,
 	&sensor_dev_attr_in12_label.dev_attr.attr,
 	&sensor_dev_attr_in13_label.dev_attr.attr,

 	NULL
 };

 ATTRIBUTE_GROUPS(powr1220);

 static int powr1220_probe(struct i2c_client *client,
 		const struct i2c_device_id *id)
 {
 	struct powr1220_data *data;
 	struct device *hwmon_dev;

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

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

 	mutex_init(&data->update_lock);
 	data->client = client;

 	hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev,
 			client->name, data, powr1220_groups);

 	return PTR_ERR_OR_ZERO(hwmon_dev);
 }

 static const struct i2c_device_id powr1220_ids[] = {
 	{ "powr1220", 0, },
 	{ }
 };

 MODULE_DEVICE_TABLE(i2c, powr1220_ids);

 static struct i2c_driver powr1220_driver = {
 	.class		= I2C_CLASS_HWMON,
 	.driver = {
 		.name	= "powr1220",
 	},
 	.probe		= powr1220_probe,
 	.id_table	= powr1220_ids,
 };

 module_i2c_driver(powr1220_driver);

 MODULE_AUTHOR("Scott Kanowitz");
 MODULE_DESCRIPTION("POWR1220 driver");
 MODULE_LICENSE("GPL");
	/*
	* powr1220.c - Driver for the Lattice POWR1220 programmable power supply
	* and monitor. Users can read all ADC inputs along with their labels
	* using the sysfs nodes.
	*
	* Copyright (c) 2014 Echo360 http://www.echo360.com
	* Scott Kanowitz <skanowitz@echo360.com> <scott.kanowitz@gmail.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.
	*/

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

	#define ADC_STEP_MV 2
	#define ADC_MAX_LOW_MEASUREMENT_MV 2000

	enum powr1220_regs {
	VMON_STATUS0,
	VMON_STATUS1,
	VMON_STATUS2,
	OUTPUT_STATUS0,
	OUTPUT_STATUS1,
	OUTPUT_STATUS2,
	INPUT_STATUS,
	ADC_VALUE_LOW,
	ADC_VALUE_HIGH,
	ADC_MUX,
	UES_BYTE0,
	UES_BYTE1,
	UES_BYTE2,
	UES_BYTE3,
	GP_OUTPUT1,
	GP_OUTPUT2,
	GP_OUTPUT3,
	INPUT_VALUE,
	RESET,
	TRIM1_TRIM,
	TRIM2_TRIM,
	TRIM3_TRIM,
	TRIM4_TRIM,
	TRIM5_TRIM,
	TRIM6_TRIM,
	TRIM7_TRIM,
	TRIM8_TRIM,
	MAX_POWR1220_REGS
	};

	enum powr1220_adc_values {
	VMON1,
	VMON2,
	VMON3,
	VMON4,
	VMON5,
	VMON6,
	VMON7,
	VMON8,
	VMON9,
	VMON10,
	VMON11,
	VMON12,
	VCCA,
	VCCINP,
	MAX_POWR1220_ADC_VALUES
	};

	struct powr1220_data {
	struct i2c_client *client;
	struct mutex update_lock;
	bool adc_valid[MAX_POWR1220_ADC_VALUES];
	/* the next value is in jiffies */
	unsigned long adc_last_updated[MAX_POWR1220_ADC_VALUES];

	/* values */
	int adc_maxes[MAX_POWR1220_ADC_VALUES];
	int adc_values[MAX_POWR1220_ADC_VALUES];
	};

	static const char * const input_names[] = {
	[VMON1] = "vmon1",
	[VMON2] = "vmon2",
	[VMON3] = "vmon3",
	[VMON4] = "vmon4",
	[VMON5] = "vmon5",
	[VMON6] = "vmon6",
	[VMON7] = "vmon7",
	[VMON8] = "vmon8",
	[VMON9] = "vmon9",
	[VMON10] = "vmon10",
	[VMON11] = "vmon11",
	[VMON12] = "vmon12",
	[VCCA] = "vcca",
	[VCCINP] = "vccinp",
	};

	/* Reads the specified ADC channel */
	static int powr1220_read_adc(struct device *dev, int ch_num)
	{
	struct powr1220_data *data = dev_get_drvdata(dev);
	int reading;
	int result;
	int adc_range = 0;

	mutex_lock(&data->update_lock);

	if (time_after(jiffies, data->adc_last_updated[ch_num] + HZ) \|\|
	!data->adc_valid[ch_num]) {
	/*
	* figure out if we need to use the attenuator for
	* high inputs or inputs that we don't yet have a measurement
	* for. We dynamically set the attenuator depending on the
	* max reading.
	*/
	if (data->adc_maxes[ch_num] > ADC_MAX_LOW_MEASUREMENT_MV \|\|
	data->adc_maxes[ch_num] == 0)
	adc_range = 1 << 4;

	/* set the attenuator and mux */
	result = i2c_smbus_write_byte_data(data->client, ADC_MUX,
	adc_range \| ch_num);
	if (result)
	goto exit;

	/*
	* wait at least Tconvert time (200 us) for the
	* conversion to complete
	*/
	udelay(200);

	/* get the ADC reading */
	result = i2c_smbus_read_byte_data(data->client, ADC_VALUE_LOW);
	if (result < 0)
	goto exit;

	reading = result >> 4;

	/* get the upper half of the reading */
	result = i2c_smbus_read_byte_data(data->client, ADC_VALUE_HIGH);
	if (result < 0)
	goto exit;

	reading \|= result << 4;

	/* now convert the reading to a voltage */
	reading *= ADC_STEP_MV;
	data->adc_values[ch_num] = reading;
	data->adc_valid[ch_num] = true;
	data->adc_last_updated[ch_num] = jiffies;
	result = reading;

	if (reading > data->adc_maxes[ch_num])
	data->adc_maxes[ch_num] = reading;
	} else {
	result = data->adc_values[ch_num];
	}

	exit:
	mutex_unlock(&data->update_lock);

	return result;
	}

	/* Shows the voltage associated with the specified ADC channel */
	static ssize_t powr1220_voltage_show(struct device *dev,
	struct device_attribute *dev_attr,
	char *buf)
	{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
	int adc_val = powr1220_read_adc(dev, attr->index);

	if (adc_val < 0)
	return adc_val;

	return sprintf(buf, "%d\n", adc_val);
	}

	/* Shows the maximum setting associated with the specified ADC channel */
	static ssize_t powr1220_max_show(struct device *dev,
	struct device_attribute dev_attr, char buf)
	{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);
	struct powr1220_data *data = dev_get_drvdata(dev);

	return sprintf(buf, "%d\n", data->adc_maxes[attr->index]);
	}

	/* Shows the label associated with the specified ADC channel */
	static ssize_t powr1220_label_show(struct device *dev,
	struct device_attribute *dev_attr,
	char *buf)
	{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(dev_attr);

	return sprintf(buf, "%s\n", input_names[attr->index]);
	}

	static SENSOR_DEVICE_ATTR_RO(in0_input, powr1220_voltage, VMON1);
	static SENSOR_DEVICE_ATTR_RO(in1_input, powr1220_voltage, VMON2);
	static SENSOR_DEVICE_ATTR_RO(in2_input, powr1220_voltage, VMON3);
	static SENSOR_DEVICE_ATTR_RO(in3_input, powr1220_voltage, VMON4);
	static SENSOR_DEVICE_ATTR_RO(in4_input, powr1220_voltage, VMON5);
	static SENSOR_DEVICE_ATTR_RO(in5_input, powr1220_voltage, VMON6);
	static SENSOR_DEVICE_ATTR_RO(in6_input, powr1220_voltage, VMON7);
	static SENSOR_DEVICE_ATTR_RO(in7_input, powr1220_voltage, VMON8);
	static SENSOR_DEVICE_ATTR_RO(in8_input, powr1220_voltage, VMON9);
	static SENSOR_DEVICE_ATTR_RO(in9_input, powr1220_voltage, VMON10);
	static SENSOR_DEVICE_ATTR_RO(in10_input, powr1220_voltage, VMON11);
	static SENSOR_DEVICE_ATTR_RO(in11_input, powr1220_voltage, VMON12);
	static SENSOR_DEVICE_ATTR_RO(in12_input, powr1220_voltage, VCCA);
	static SENSOR_DEVICE_ATTR_RO(in13_input, powr1220_voltage, VCCINP);

	static SENSOR_DEVICE_ATTR_RO(in0_highest, powr1220_max, VMON1);
	static SENSOR_DEVICE_ATTR_RO(in1_highest, powr1220_max, VMON2);
	static SENSOR_DEVICE_ATTR_RO(in2_highest, powr1220_max, VMON3);
	static SENSOR_DEVICE_ATTR_RO(in3_highest, powr1220_max, VMON4);
	static SENSOR_DEVICE_ATTR_RO(in4_highest, powr1220_max, VMON5);
	static SENSOR_DEVICE_ATTR_RO(in5_highest, powr1220_max, VMON6);
	static SENSOR_DEVICE_ATTR_RO(in6_highest, powr1220_max, VMON7);
	static SENSOR_DEVICE_ATTR_RO(in7_highest, powr1220_max, VMON8);
	static SENSOR_DEVICE_ATTR_RO(in8_highest, powr1220_max, VMON9);
	static SENSOR_DEVICE_ATTR_RO(in9_highest, powr1220_max, VMON10);
	static SENSOR_DEVICE_ATTR_RO(in10_highest, powr1220_max, VMON11);
	static SENSOR_DEVICE_ATTR_RO(in11_highest, powr1220_max, VMON12);
	static SENSOR_DEVICE_ATTR_RO(in12_highest, powr1220_max, VCCA);
	static SENSOR_DEVICE_ATTR_RO(in13_highest, powr1220_max, VCCINP);

	static SENSOR_DEVICE_ATTR_RO(in0_label, powr1220_label, VMON1);
	static SENSOR_DEVICE_ATTR_RO(in1_label, powr1220_label, VMON2);
	static SENSOR_DEVICE_ATTR_RO(in2_label, powr1220_label, VMON3);
	static SENSOR_DEVICE_ATTR_RO(in3_label, powr1220_label, VMON4);
	static SENSOR_DEVICE_ATTR_RO(in4_label, powr1220_label, VMON5);
	static SENSOR_DEVICE_ATTR_RO(in5_label, powr1220_label, VMON6);
	static SENSOR_DEVICE_ATTR_RO(in6_label, powr1220_label, VMON7);
	static SENSOR_DEVICE_ATTR_RO(in7_label, powr1220_label, VMON8);
	static SENSOR_DEVICE_ATTR_RO(in8_label, powr1220_label, VMON9);
	static SENSOR_DEVICE_ATTR_RO(in9_label, powr1220_label, VMON10);
	static SENSOR_DEVICE_ATTR_RO(in10_label, powr1220_label, VMON11);
	static SENSOR_DEVICE_ATTR_RO(in11_label, powr1220_label, VMON12);
	static SENSOR_DEVICE_ATTR_RO(in12_label, powr1220_label, VCCA);
	static SENSOR_DEVICE_ATTR_RO(in13_label, powr1220_label, VCCINP);

	static struct attribute *powr1220_attrs[] = {
	&sensor_dev_attr_in0_input.dev_attr.attr,
	&sensor_dev_attr_in1_input.dev_attr.attr,
	&sensor_dev_attr_in2_input.dev_attr.attr,
	&sensor_dev_attr_in3_input.dev_attr.attr,
	&sensor_dev_attr_in4_input.dev_attr.attr,
	&sensor_dev_attr_in5_input.dev_attr.attr,
	&sensor_dev_attr_in6_input.dev_attr.attr,
	&sensor_dev_attr_in7_input.dev_attr.attr,
	&sensor_dev_attr_in8_input.dev_attr.attr,
	&sensor_dev_attr_in9_input.dev_attr.attr,
	&sensor_dev_attr_in10_input.dev_attr.attr,
	&sensor_dev_attr_in11_input.dev_attr.attr,
	&sensor_dev_attr_in12_input.dev_attr.attr,
	&sensor_dev_attr_in13_input.dev_attr.attr,

	&sensor_dev_attr_in0_highest.dev_attr.attr,
	&sensor_dev_attr_in1_highest.dev_attr.attr,
	&sensor_dev_attr_in2_highest.dev_attr.attr,
	&sensor_dev_attr_in3_highest.dev_attr.attr,
	&sensor_dev_attr_in4_highest.dev_attr.attr,
	&sensor_dev_attr_in5_highest.dev_attr.attr,
	&sensor_dev_attr_in6_highest.dev_attr.attr,
	&sensor_dev_attr_in7_highest.dev_attr.attr,
	&sensor_dev_attr_in8_highest.dev_attr.attr,
	&sensor_dev_attr_in9_highest.dev_attr.attr,
	&sensor_dev_attr_in10_highest.dev_attr.attr,
	&sensor_dev_attr_in11_highest.dev_attr.attr,
	&sensor_dev_attr_in12_highest.dev_attr.attr,
	&sensor_dev_attr_in13_highest.dev_attr.attr,

	&sensor_dev_attr_in0_label.dev_attr.attr,
	&sensor_dev_attr_in1_label.dev_attr.attr,
	&sensor_dev_attr_in2_label.dev_attr.attr,
	&sensor_dev_attr_in3_label.dev_attr.attr,
	&sensor_dev_attr_in4_label.dev_attr.attr,
	&sensor_dev_attr_in5_label.dev_attr.attr,
	&sensor_dev_attr_in6_label.dev_attr.attr,
	&sensor_dev_attr_in7_label.dev_attr.attr,
	&sensor_dev_attr_in8_label.dev_attr.attr,
	&sensor_dev_attr_in9_label.dev_attr.attr,
	&sensor_dev_attr_in10_label.dev_attr.attr,
	&sensor_dev_attr_in11_label.dev_attr.attr,
	&sensor_dev_attr_in12_label.dev_attr.attr,
	&sensor_dev_attr_in13_label.dev_attr.attr,

	NULL
	};

	ATTRIBUTE_GROUPS(powr1220);

	static int powr1220_probe(struct i2c_client *client,
	const struct i2c_device_id *id)
	{
	struct powr1220_data *data;
	struct device *hwmon_dev;

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

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

	mutex_init(&data->update_lock);
	data->client = client;

	hwmon_dev = devm_hwmon_device_register_with_groups(&client->dev,
	client->name, data, powr1220_groups);

	return PTR_ERR_OR_ZERO(hwmon_dev);
	}

	static const struct i2c_device_id powr1220_ids[] = {
	{ "powr1220", 0, },
	{ }
	};

	MODULE_DEVICE_TABLE(i2c, powr1220_ids);

	static struct i2c_driver powr1220_driver = {
	.class = I2C_CLASS_HWMON,
	.driver = {
	.name = "powr1220",
	},
	.probe = powr1220_probe,
	.id_table = powr1220_ids,
	};

	module_i2c_driver(powr1220_driver);

	MODULE_AUTHOR("Scott Kanowitz");
	MODULE_DESCRIPTION("POWR1220 driver");
	MODULE_LICENSE("GPL");