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

 // SPDX-License-Identifier: GPL-2.0-or-later
 /*
  * 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 https://www.echo360.com
  * Scott Kanowitz <skanowitz@echo360.com> <scott.kanowitz@gmail.com>
  */

 #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 powr1xxx_chips { powr1014, powr1220 };

 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;
 	u8 max_channels;
 	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;
 }

 static umode_t
 powr1220_is_visible(const void *data, enum hwmon_sensor_types type, u32
 		    attr, int channel)
 {
 	struct powr1220_data *chip_data = (struct powr1220_data *)data;

 	if (channel >= chip_data->max_channels)
 		return 0;

 	switch (type) {
 	case hwmon_in:
 		switch (attr) {
 		case hwmon_in_input:
 		case hwmon_in_highest:
 		case hwmon_in_label:
 			return 0444;
 		default:
 			break;
 		}
 		break;
 	default:
 		break;
 	}

 	return 0;
 }

 static int
 powr1220_read_string(struct device *dev, enum hwmon_sensor_types type, u32 attr,
 		     int channel, const char **str)
 {
 	switch (type) {
 	case hwmon_in:
 		switch (attr) {
 		case hwmon_in_label:
 			*str = input_names[channel];
 			return 0;
 		default:
 			return -EOPNOTSUPP;
 		}
 		break;
 	default:
 		return -EOPNOTSUPP;
 	}

 	return -EOPNOTSUPP;
 }

 static int
 powr1220_read(struct device *dev, enum hwmon_sensor_types type, u32
 	      attr, int channel, long *val)
 {
 	struct powr1220_data *data = dev_get_drvdata(dev);
 	int ret;

 	switch (type) {
 	case hwmon_in:
 		switch (attr) {
 		case hwmon_in_input:
 			ret = powr1220_read_adc(dev, channel);
 			if (ret < 0)
 				return ret;
 			*val = ret;
 			break;
 		case hwmon_in_highest:
 			*val = data->adc_maxes[channel];
 			break;
 		default:
 			return -EOPNOTSUPP;
 		}
 		break;
 	default:
 		return -EOPNOTSUPP;
 }

 	return 0;
 }

 static const struct hwmon_channel_info * const powr1220_info[] = {
 	HWMON_CHANNEL_INFO(in,
 			   HWMON_I_INPUT | HWMON_I_HIGHEST | HWMON_I_LABEL,
 			   HWMON_I_INPUT | HWMON_I_HIGHEST | HWMON_I_LABEL,
 			   HWMON_I_INPUT | HWMON_I_HIGHEST | HWMON_I_LABEL,
 			   HWMON_I_INPUT | HWMON_I_HIGHEST | HWMON_I_LABEL,
 			   HWMON_I_INPUT | HWMON_I_HIGHEST | HWMON_I_LABEL,
 			   HWMON_I_INPUT | HWMON_I_HIGHEST | HWMON_I_LABEL,
 			   HWMON_I_INPUT | HWMON_I_HIGHEST | HWMON_I_LABEL,
 			   HWMON_I_INPUT | HWMON_I_HIGHEST | HWMON_I_LABEL,
 			   HWMON_I_INPUT | HWMON_I_HIGHEST | HWMON_I_LABEL,
 			   HWMON_I_INPUT | HWMON_I_HIGHEST | HWMON_I_LABEL,
 			   HWMON_I_INPUT | HWMON_I_HIGHEST | HWMON_I_LABEL,
 			   HWMON_I_INPUT | HWMON_I_HIGHEST | HWMON_I_LABEL,
 			   HWMON_I_INPUT | HWMON_I_HIGHEST | HWMON_I_LABEL,
 			   HWMON_I_INPUT | HWMON_I_HIGHEST | HWMON_I_LABEL),

 	NULL
 };

 static const struct hwmon_ops powr1220_hwmon_ops = {
 	.read = powr1220_read,
 	.read_string = powr1220_read_string,
 	.is_visible = powr1220_is_visible,
 };

 static const struct hwmon_chip_info powr1220_chip_info = {
 	.ops = &powr1220_hwmon_ops,
 	.info = powr1220_info,
 };

 static const struct i2c_device_id powr1220_ids[];

 static int powr1220_probe(struct i2c_client *client)
 {
 	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;

 	switch (i2c_match_id(powr1220_ids, client)->driver_data) {
 	case powr1014:
 		data->max_channels = 10;
 		break;
 	default:
 		data->max_channels = 12;
 		break;
 	}

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

 	hwmon_dev = devm_hwmon_device_register_with_info(&client->dev,
 							 client->name,
 							 data,
 							 &powr1220_chip_info,
 							 NULL);

 	return PTR_ERR_OR_ZERO(hwmon_dev);
 }

 static const struct i2c_device_id powr1220_ids[] = {
 	{ "powr1014", powr1014, },
 	{ "powr1220", powr1220, },
 	{ }
 };

 MODULE_DEVICE_TABLE(i2c, powr1220_ids);

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

 module_i2c_driver(powr1220_driver);

 MODULE_AUTHOR("Scott Kanowitz");
 MODULE_DESCRIPTION("POWR1220 driver");
 MODULE_LICENSE("GPL");
	// SPDX-License-Identifier: GPL-2.0-or-later
	/*
	* 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 https://www.echo360.com
	* Scott Kanowitz <skanowitz@echo360.com> <scott.kanowitz@gmail.com>
	*/

	#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 powr1xxx_chips { powr1014, powr1220 };

	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;
	u8 max_channels;
	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;
	}

	static umode_t
	powr1220_is_visible(const void *data, enum hwmon_sensor_types type, u32
	attr, int channel)
	{
	struct powr1220_data chip_data = (struct powr1220_data )data;

	if (channel >= chip_data->max_channels)
	return 0;

	switch (type) {
	case hwmon_in:
	switch (attr) {
	case hwmon_in_input:
	case hwmon_in_highest:
	case hwmon_in_label:
	return 0444;
	default:
	break;
	}
	break;
	default:
	break;
	}

	return 0;
	}

	static int
	powr1220_read_string(struct device *dev, enum hwmon_sensor_types type, u32 attr,
	int channel, const char **str)
	{
	switch (type) {
	case hwmon_in:
	switch (attr) {
	case hwmon_in_label:
	*str = input_names[channel];
	return 0;
	default:
	return -EOPNOTSUPP;
	}
	break;
	default:
	return -EOPNOTSUPP;
	}

	return -EOPNOTSUPP;
	}

	static int
	powr1220_read(struct device *dev, enum hwmon_sensor_types type, u32
	attr, int channel, long *val)
	{
	struct powr1220_data *data = dev_get_drvdata(dev);
	int ret;

	switch (type) {
	case hwmon_in:
	switch (attr) {
	case hwmon_in_input:
	ret = powr1220_read_adc(dev, channel);
	if (ret < 0)
	return ret;
	*val = ret;
	break;
	case hwmon_in_highest:
	*val = data->adc_maxes[channel];
	break;
	default:
	return -EOPNOTSUPP;
	}
	break;
	default:
	return -EOPNOTSUPP;
	}

	return 0;
	}

	static const struct hwmon_channel_info * const powr1220_info[] = {
	HWMON_CHANNEL_INFO(in,
	HWMON_I_INPUT \| HWMON_I_HIGHEST \| HWMON_I_LABEL,
	HWMON_I_INPUT \| HWMON_I_HIGHEST \| HWMON_I_LABEL,
	HWMON_I_INPUT \| HWMON_I_HIGHEST \| HWMON_I_LABEL,
	HWMON_I_INPUT \| HWMON_I_HIGHEST \| HWMON_I_LABEL,
	HWMON_I_INPUT \| HWMON_I_HIGHEST \| HWMON_I_LABEL,
	HWMON_I_INPUT \| HWMON_I_HIGHEST \| HWMON_I_LABEL,
	HWMON_I_INPUT \| HWMON_I_HIGHEST \| HWMON_I_LABEL,
	HWMON_I_INPUT \| HWMON_I_HIGHEST \| HWMON_I_LABEL,
	HWMON_I_INPUT \| HWMON_I_HIGHEST \| HWMON_I_LABEL,
	HWMON_I_INPUT \| HWMON_I_HIGHEST \| HWMON_I_LABEL,
	HWMON_I_INPUT \| HWMON_I_HIGHEST \| HWMON_I_LABEL,
	HWMON_I_INPUT \| HWMON_I_HIGHEST \| HWMON_I_LABEL,
	HWMON_I_INPUT \| HWMON_I_HIGHEST \| HWMON_I_LABEL,
	HWMON_I_INPUT \| HWMON_I_HIGHEST \| HWMON_I_LABEL),

	NULL
	};

	static const struct hwmon_ops powr1220_hwmon_ops = {
	.read = powr1220_read,
	.read_string = powr1220_read_string,
	.is_visible = powr1220_is_visible,
	};

	static const struct hwmon_chip_info powr1220_chip_info = {
	.ops = &powr1220_hwmon_ops,
	.info = powr1220_info,
	};

	static const struct i2c_device_id powr1220_ids[];

	static int powr1220_probe(struct i2c_client *client)
	{
	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;

	switch (i2c_match_id(powr1220_ids, client)->driver_data) {
	case powr1014:
	data->max_channels = 10;
	break;
	default:
	data->max_channels = 12;
	break;
	}

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

	hwmon_dev = devm_hwmon_device_register_with_info(&client->dev,
	client->name,
	data,
	&powr1220_chip_info,
	NULL);

	return PTR_ERR_OR_ZERO(hwmon_dev);
	}

	static const struct i2c_device_id powr1220_ids[] = {
	{ "powr1014", powr1014, },
	{ "powr1220", powr1220, },
	{ }
	};

	MODULE_DEVICE_TABLE(i2c, powr1220_ids);

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

	module_i2c_driver(powr1220_driver);

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