[linux-block.git] / drivers / hwmon / ltc2945.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Driver for Linear Technology LTC2945 I2C Power Monitor
 *
 * Copyright (c) 2014 Guenter Roeck
 */

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

/* chip registers */
#define LTC2945_CONTROL			0x00
#define LTC2945_ALERT			0x01
#define LTC2945_STATUS			0x02
#define LTC2945_FAULT			0x03
#define LTC2945_POWER_H			0x05
#define LTC2945_MAX_POWER_H		0x08
#define LTC2945_MIN_POWER_H		0x0b
#define LTC2945_MAX_POWER_THRES_H	0x0e
#define LTC2945_MIN_POWER_THRES_H	0x11
#define LTC2945_SENSE_H			0x14
#define LTC2945_MAX_SENSE_H		0x16
#define LTC2945_MIN_SENSE_H		0x18
#define LTC2945_MAX_SENSE_THRES_H	0x1a
#define LTC2945_MIN_SENSE_THRES_H	0x1c
#define LTC2945_VIN_H			0x1e
#define LTC2945_MAX_VIN_H		0x20
#define LTC2945_MIN_VIN_H		0x22
#define LTC2945_MAX_VIN_THRES_H		0x24
#define LTC2945_MIN_VIN_THRES_H		0x26
#define LTC2945_ADIN_H			0x28
#define LTC2945_MAX_ADIN_H		0x2a
#define LTC2945_MIN_ADIN_H		0x2c
#define LTC2945_MAX_ADIN_THRES_H	0x2e
#define LTC2945_MIN_ADIN_THRES_H	0x30
#define LTC2945_MIN_ADIN_THRES_L	0x31

/* Fault register bits */

#define FAULT_ADIN_UV		(1 << 0)
#define FAULT_ADIN_OV		(1 << 1)
#define FAULT_VIN_UV		(1 << 2)
#define FAULT_VIN_OV		(1 << 3)
#define FAULT_SENSE_UV		(1 << 4)
#define FAULT_SENSE_OV		(1 << 5)
#define FAULT_POWER_UV		(1 << 6)
#define FAULT_POWER_OV		(1 << 7)

/* Control register bits */

#define CONTROL_MULT_SELECT	(1 << 0)
#define CONTROL_TEST_MODE	(1 << 4)

static inline bool is_power_reg(u8 reg)
{
	return reg < LTC2945_SENSE_H;
}

/* Return the value from the given register in uW, mV, or mA */
static long long ltc2945_reg_to_val(struct device *dev, u8 reg)
{
	struct regmap *regmap = dev_get_drvdata(dev);
	unsigned int control;
	u8 buf[3];
	long long val;
	int ret;

	ret = regmap_bulk_read(regmap, reg, buf,
			       is_power_reg(reg) ? 3 : 2);
	if (ret < 0)
		return ret;

	if (is_power_reg(reg)) {
		/* power */
		val = (buf[0] << 16) + (buf[1] << 8) + buf[2];
	} else {
		/* current, voltage */
		val = (buf[0] << 4) + (buf[1] >> 4);
	}

	switch (reg) {
	case LTC2945_POWER_H:
	case LTC2945_MAX_POWER_H:
	case LTC2945_MIN_POWER_H:
	case LTC2945_MAX_POWER_THRES_H:
	case LTC2945_MIN_POWER_THRES_H:
		/*
		 * Convert to uW by assuming current is measured with
		 * an 1mOhm sense resistor, similar to current
		 * measurements.
		 * Control register bit 0 selects if voltage at SENSE+/VDD
		 * or voltage at ADIN is used to measure power.
		 */
		ret = regmap_read(regmap, LTC2945_CONTROL, &control);
		if (ret < 0)
			return ret;
		if (control & CONTROL_MULT_SELECT) {
			/* 25 mV * 25 uV = 0.625 uV resolution. */
			val *= 625LL;
		} else {
			/* 0.5 mV * 25 uV = 0.0125 uV resolution. */
			val = (val * 25LL) >> 1;
		}
		break;
	case LTC2945_VIN_H:
	case LTC2945_MAX_VIN_H:
	case LTC2945_MIN_VIN_H:
	case LTC2945_MAX_VIN_THRES_H:
	case LTC2945_MIN_VIN_THRES_H:
		/* 25 mV resolution. Convert to mV. */
		val *= 25;
		break;
	case LTC2945_ADIN_H:
	case LTC2945_MAX_ADIN_H:
	case LTC2945_MIN_ADIN_THRES_H:
	case LTC2945_MAX_ADIN_THRES_H:
	case LTC2945_MIN_ADIN_H:
		/* 0.5mV resolution. Convert to mV. */
		val = val >> 1;
		break;
	case LTC2945_SENSE_H:
	case LTC2945_MAX_SENSE_H:
	case LTC2945_MIN_SENSE_H:
	case LTC2945_MAX_SENSE_THRES_H:
	case LTC2945_MIN_SENSE_THRES_H:
		/*
		 * 25 uV resolution. Convert to current as measured with
		 * an 1 mOhm sense resistor, in mA. If a different sense
		 * resistor is installed, calculate the actual current by
		 * dividing the reported current by the sense resistor value
		 * in mOhm.
		 */
		val *= 25;
		break;
	default:
		return -EINVAL;
	}
	return val;
}

static int ltc2945_val_to_reg(struct device *dev, u8 reg,
			      unsigned long val)
{
	struct regmap *regmap = dev_get_drvdata(dev);
	unsigned int control;
	int ret;

	switch (reg) {
	case LTC2945_POWER_H:
	case LTC2945_MAX_POWER_H:
	case LTC2945_MIN_POWER_H:
	case LTC2945_MAX_POWER_THRES_H:
	case LTC2945_MIN_POWER_THRES_H:
		/*
		 * Convert to register value by assuming current is measured
		 * with an 1mOhm sense resistor, similar to current
		 * measurements.
		 * Control register bit 0 selects if voltage at SENSE+/VDD
		 * or voltage at ADIN is used to measure power, which in turn
		 * determines register calculations.
		 */
		ret = regmap_read(regmap, LTC2945_CONTROL, &control);
		if (ret < 0)
			return ret;
		if (control & CONTROL_MULT_SELECT) {
			/* 25 mV * 25 uV = 0.625 uV resolution. */
			val = DIV_ROUND_CLOSEST(val, 625);
		} else {
			/*
			 * 0.5 mV * 25 uV = 0.0125 uV resolution.
			 * Divide first to avoid overflow;
			 * accept loss of accuracy.
			 */
			val = DIV_ROUND_CLOSEST(val, 25) * 2;
		}
		break;
	case LTC2945_VIN_H:
	case LTC2945_MAX_VIN_H:
	case LTC2945_MIN_VIN_H:
	case LTC2945_MAX_VIN_THRES_H:
	case LTC2945_MIN_VIN_THRES_H:
		/* 25 mV resolution. */
		val /= 25;
		break;
	case LTC2945_ADIN_H:
	case LTC2945_MAX_ADIN_H:
	case LTC2945_MIN_ADIN_THRES_H:
	case LTC2945_MAX_ADIN_THRES_H:
	case LTC2945_MIN_ADIN_H:
		/* 0.5mV resolution. */
		val *= 2;
		break;
	case LTC2945_SENSE_H:
	case LTC2945_MAX_SENSE_H:
	case LTC2945_MIN_SENSE_H:
	case LTC2945_MAX_SENSE_THRES_H:
	case LTC2945_MIN_SENSE_THRES_H:
		/*
		 * 25 uV resolution. Convert to current as measured with
		 * an 1 mOhm sense resistor, in mA. If a different sense
		 * resistor is installed, calculate the actual current by
		 * dividing the reported current by the sense resistor value
		 * in mOhm.
		 */
		val = DIV_ROUND_CLOSEST(val, 25);
		break;
	default:
		return -EINVAL;
	}
	return val;
}

static ssize_t ltc2945_value_show(struct device *dev,
				  struct device_attribute *da, char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	long long value;

	value = ltc2945_reg_to_val(dev, attr->index);
	if (value < 0)
		return value;
	return snprintf(buf, PAGE_SIZE, "%lld\n", value);
}

static ssize_t ltc2945_value_store(struct device *dev,
				   struct device_attribute *da,
				   const char *buf, size_t count)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	struct regmap *regmap = dev_get_drvdata(dev);
	u8 reg = attr->index;
	unsigned long val;
	u8 regbuf[3];
	int num_regs;
	int regval;
	int ret;

	ret = kstrtoul(buf, 10, &val);
	if (ret)
		return ret;

	/* convert to register value, then clamp and write result */
	regval = ltc2945_val_to_reg(dev, reg, val);
	if (is_power_reg(reg)) {
		regval = clamp_val(regval, 0, 0xffffff);
		regbuf[0] = regval >> 16;
		regbuf[1] = (regval >> 8) & 0xff;
		regbuf[2] = regval;
		num_regs = 3;
	} else {
		regval = clamp_val(regval, 0, 0xfff) << 4;
		regbuf[0] = regval >> 8;
		regbuf[1] = regval & 0xff;
		num_regs = 2;
	}
	ret = regmap_bulk_write(regmap, reg, regbuf, num_regs);
	return ret < 0 ? ret : count;
}

static ssize_t ltc2945_history_store(struct device *dev,
				     struct device_attribute *da,
				     const char *buf, size_t count)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	struct regmap *regmap = dev_get_drvdata(dev);
	u8 reg = attr->index;
	int num_regs = is_power_reg(reg) ? 3 : 2;
	u8 buf_min[3] = { 0xff, 0xff, 0xff };
	u8 buf_max[3] = { 0, 0, 0 };
	unsigned long val;
	int ret;

	ret = kstrtoul(buf, 10, &val);
	if (ret)
		return ret;
	if (val != 1)
		return -EINVAL;

	ret = regmap_update_bits(regmap, LTC2945_CONTROL, CONTROL_TEST_MODE,
				 CONTROL_TEST_MODE);

	/* Reset minimum */
	ret = regmap_bulk_write(regmap, reg, buf_min, num_regs);
	if (ret)
		return ret;

	switch (reg) {
	case LTC2945_MIN_POWER_H:
		reg = LTC2945_MAX_POWER_H;
		break;
	case LTC2945_MIN_SENSE_H:
		reg = LTC2945_MAX_SENSE_H;
		break;
	case LTC2945_MIN_VIN_H:
		reg = LTC2945_MAX_VIN_H;
		break;
	case LTC2945_MIN_ADIN_H:
		reg = LTC2945_MAX_ADIN_H;
		break;
	default:
		WARN_ONCE(1, "Bad register: 0x%x\n", reg);
		return -EINVAL;
	}
	/* Reset maximum */
	ret = regmap_bulk_write(regmap, reg, buf_max, num_regs);

	/* Try resetting test mode even if there was an error */
	regmap_update_bits(regmap, LTC2945_CONTROL, CONTROL_TEST_MODE, 0);

	return ret ? : count;
}

static ssize_t ltc2945_bool_show(struct device *dev,
				 struct device_attribute *da, char *buf)
{
	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	struct regmap *regmap = dev_get_drvdata(dev);
	unsigned int fault;
	int ret;

	ret = regmap_read(regmap, LTC2945_FAULT, &fault);
	if (ret < 0)
		return ret;

	fault &= attr->index;
	if (fault)		/* Clear reported faults in chip register */
		regmap_update_bits(regmap, LTC2945_FAULT, attr->index, 0);

	return snprintf(buf, PAGE_SIZE, "%d\n", !!fault);
}

/* Input voltages */

static SENSOR_DEVICE_ATTR_RO(in1_input, ltc2945_value, LTC2945_VIN_H);
static SENSOR_DEVICE_ATTR_RW(in1_min, ltc2945_value, LTC2945_MIN_VIN_THRES_H);
static SENSOR_DEVICE_ATTR_RW(in1_max, ltc2945_value, LTC2945_MAX_VIN_THRES_H);
static SENSOR_DEVICE_ATTR_RO(in1_lowest, ltc2945_value, LTC2945_MIN_VIN_H);
static SENSOR_DEVICE_ATTR_RO(in1_highest, ltc2945_value, LTC2945_MAX_VIN_H);
static SENSOR_DEVICE_ATTR_WO(in1_reset_history, ltc2945_history,
			     LTC2945_MIN_VIN_H);

static SENSOR_DEVICE_ATTR_RO(in2_input, ltc2945_value, LTC2945_ADIN_H);
static SENSOR_DEVICE_ATTR_RW(in2_min, ltc2945_value, LTC2945_MIN_ADIN_THRES_H);
static SENSOR_DEVICE_ATTR_RW(in2_max, ltc2945_value, LTC2945_MAX_ADIN_THRES_H);
static SENSOR_DEVICE_ATTR_RO(in2_lowest, ltc2945_value, LTC2945_MIN_ADIN_H);
static SENSOR_DEVICE_ATTR_RO(in2_highest, ltc2945_value, LTC2945_MAX_ADIN_H);
static SENSOR_DEVICE_ATTR_WO(in2_reset_history, ltc2945_history,
			     LTC2945_MIN_ADIN_H);

/* Voltage alarms */

static SENSOR_DEVICE_ATTR_RO(in1_min_alarm, ltc2945_bool, FAULT_VIN_UV);
static SENSOR_DEVICE_ATTR_RO(in1_max_alarm, ltc2945_bool, FAULT_VIN_OV);
static SENSOR_DEVICE_ATTR_RO(in2_min_alarm, ltc2945_bool, FAULT_ADIN_UV);
static SENSOR_DEVICE_ATTR_RO(in2_max_alarm, ltc2945_bool, FAULT_ADIN_OV);

/* Currents (via sense resistor) */

static SENSOR_DEVICE_ATTR_RO(curr1_input, ltc2945_value, LTC2945_SENSE_H);
static SENSOR_DEVICE_ATTR_RW(curr1_min, ltc2945_value,
			     LTC2945_MIN_SENSE_THRES_H);
static SENSOR_DEVICE_ATTR_RW(curr1_max, ltc2945_value,
			     LTC2945_MAX_SENSE_THRES_H);
static SENSOR_DEVICE_ATTR_RO(curr1_lowest, ltc2945_value, LTC2945_MIN_SENSE_H);
static SENSOR_DEVICE_ATTR_RO(curr1_highest, ltc2945_value,
			     LTC2945_MAX_SENSE_H);
static SENSOR_DEVICE_ATTR_WO(curr1_reset_history, ltc2945_history,
			     LTC2945_MIN_SENSE_H);

/* Current alarms */

static SENSOR_DEVICE_ATTR_RO(curr1_min_alarm, ltc2945_bool, FAULT_SENSE_UV);
static SENSOR_DEVICE_ATTR_RO(curr1_max_alarm, ltc2945_bool, FAULT_SENSE_OV);

/* Power */

static SENSOR_DEVICE_ATTR_RO(power1_input, ltc2945_value, LTC2945_POWER_H);
static SENSOR_DEVICE_ATTR_RW(power1_min, ltc2945_value,
			     LTC2945_MIN_POWER_THRES_H);
static SENSOR_DEVICE_ATTR_RW(power1_max, ltc2945_value,
			     LTC2945_MAX_POWER_THRES_H);
static SENSOR_DEVICE_ATTR_RO(power1_input_lowest, ltc2945_value,
			     LTC2945_MIN_POWER_H);
static SENSOR_DEVICE_ATTR_RO(power1_input_highest, ltc2945_value,
			     LTC2945_MAX_POWER_H);
static SENSOR_DEVICE_ATTR_WO(power1_reset_history, ltc2945_history,
			     LTC2945_MIN_POWER_H);

/* Power alarms */

static SENSOR_DEVICE_ATTR_RO(power1_min_alarm, ltc2945_bool, FAULT_POWER_UV);
static SENSOR_DEVICE_ATTR_RO(power1_max_alarm, ltc2945_bool, FAULT_POWER_OV);

static struct attribute *ltc2945_attrs[] = {
	&sensor_dev_attr_in1_input.dev_attr.attr,
	&sensor_dev_attr_in1_min.dev_attr.attr,
	&sensor_dev_attr_in1_max.dev_attr.attr,
	&sensor_dev_attr_in1_lowest.dev_attr.attr,
	&sensor_dev_attr_in1_highest.dev_attr.attr,
	&sensor_dev_attr_in1_reset_history.dev_attr.attr,
	&sensor_dev_attr_in1_min_alarm.dev_attr.attr,
	&sensor_dev_attr_in1_max_alarm.dev_attr.attr,

	&sensor_dev_attr_in2_input.dev_attr.attr,
	&sensor_dev_attr_in2_min.dev_attr.attr,
	&sensor_dev_attr_in2_max.dev_attr.attr,
	&sensor_dev_attr_in2_lowest.dev_attr.attr,
	&sensor_dev_attr_in2_highest.dev_attr.attr,
	&sensor_dev_attr_in2_reset_history.dev_attr.attr,
	&sensor_dev_attr_in2_min_alarm.dev_attr.attr,
	&sensor_dev_attr_in2_max_alarm.dev_attr.attr,

	&sensor_dev_attr_curr1_input.dev_attr.attr,
	&sensor_dev_attr_curr1_min.dev_attr.attr,
	&sensor_dev_attr_curr1_max.dev_attr.attr,
	&sensor_dev_attr_curr1_lowest.dev_attr.attr,
	&sensor_dev_attr_curr1_highest.dev_attr.attr,
	&sensor_dev_attr_curr1_reset_history.dev_attr.attr,
	&sensor_dev_attr_curr1_min_alarm.dev_attr.attr,
	&sensor_dev_attr_curr1_max_alarm.dev_attr.attr,

	&sensor_dev_attr_power1_input.dev_attr.attr,
	&sensor_dev_attr_power1_min.dev_attr.attr,
	&sensor_dev_attr_power1_max.dev_attr.attr,
	&sensor_dev_attr_power1_input_lowest.dev_attr.attr,
	&sensor_dev_attr_power1_input_highest.dev_attr.attr,
	&sensor_dev_attr_power1_reset_history.dev_attr.attr,
	&sensor_dev_attr_power1_min_alarm.dev_attr.attr,
	&sensor_dev_attr_power1_max_alarm.dev_attr.attr,

	NULL,
};
ATTRIBUTE_GROUPS(ltc2945);

static const struct regmap_config ltc2945_regmap_config = {
	.reg_bits = 8,
	.val_bits = 8,
	.max_register = LTC2945_MIN_ADIN_THRES_L,
};

static int ltc2945_probe(struct i2c_client *client)
{
	struct device *dev = &client->dev;
	struct device *hwmon_dev;
	struct regmap *regmap;

	regmap = devm_regmap_init_i2c(client, &ltc2945_regmap_config);
	if (IS_ERR(regmap)) {
		dev_err(dev, "failed to allocate register map\n");
		return PTR_ERR(regmap);
	}

	/* Clear faults */
	regmap_write(regmap, LTC2945_FAULT, 0x00);

	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
							   regmap,
							   ltc2945_groups);
	return PTR_ERR_OR_ZERO(hwmon_dev);
}

static const struct i2c_device_id ltc2945_id[] = {
	{"ltc2945", 0},
	{ }
};

MODULE_DEVICE_TABLE(i2c, ltc2945_id);

static struct i2c_driver ltc2945_driver = {
	.driver = {
		   .name = "ltc2945",
		   },
	.probe_new = ltc2945_probe,
	.id_table = ltc2945_id,
};

module_i2c_driver(ltc2945_driver);

MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
MODULE_DESCRIPTION("LTC2945 driver");
MODULE_LICENSE("GPL");
Commit	Line	Data
c942fddf	1	// SPDX-License-Identifier: GPL-2.0-or-later
86b89d73	2	/*
6700ce03 GR	3	* Driver for Linear Technology LTC2945 I2C Power Monitor
	4	*
	5	* Copyright (c) 2014 Guenter Roeck
6700ce03 GR	6	*/
	7
	8	#include <linux/kernel.h>
	9	#include <linux/module.h>
	10	#include <linux/err.h>
	11	#include <linux/slab.h>
	12	#include <linux/i2c.h>
	13	#include <linux/hwmon.h>
	14	#include <linux/hwmon-sysfs.h>
	15	#include <linux/jiffies.h>
	16	#include <linux/regmap.h>
	17
	18	/* chip registers */
	19	#define LTC2945_CONTROL 0x00
	20	#define LTC2945_ALERT 0x01
	21	#define LTC2945_STATUS 0x02
	22	#define LTC2945_FAULT 0x03
	23	#define LTC2945_POWER_H 0x05
	24	#define LTC2945_MAX_POWER_H 0x08
	25	#define LTC2945_MIN_POWER_H 0x0b
	26	#define LTC2945_MAX_POWER_THRES_H 0x0e
	27	#define LTC2945_MIN_POWER_THRES_H 0x11
	28	#define LTC2945_SENSE_H 0x14
	29	#define LTC2945_MAX_SENSE_H 0x16
	30	#define LTC2945_MIN_SENSE_H 0x18
	31	#define LTC2945_MAX_SENSE_THRES_H 0x1a
	32	#define LTC2945_MIN_SENSE_THRES_H 0x1c
	33	#define LTC2945_VIN_H 0x1e
	34	#define LTC2945_MAX_VIN_H 0x20
	35	#define LTC2945_MIN_VIN_H 0x22
	36	#define LTC2945_MAX_VIN_THRES_H 0x24
	37	#define LTC2945_MIN_VIN_THRES_H 0x26
	38	#define LTC2945_ADIN_H 0x28
	39	#define LTC2945_MAX_ADIN_H 0x2a
	40	#define LTC2945_MIN_ADIN_H 0x2c
	41	#define LTC2945_MAX_ADIN_THRES_H 0x2e
	42	#define LTC2945_MIN_ADIN_THRES_H 0x30
	43	#define LTC2945_MIN_ADIN_THRES_L 0x31
	44
	45	/* Fault register bits */
	46
	47	#define FAULT_ADIN_UV (1 << 0)
	48	#define FAULT_ADIN_OV (1 << 1)
	49	#define FAULT_VIN_UV (1 << 2)
	50	#define FAULT_VIN_OV (1 << 3)
	51	#define FAULT_SENSE_UV (1 << 4)
	52	#define FAULT_SENSE_OV (1 << 5)
	53	#define FAULT_POWER_UV (1 << 6)
	54	#define FAULT_POWER_OV (1 << 7)
	55
	56	/* Control register bits */
	57
	58	#define CONTROL_MULT_SELECT (1 << 0)
	59	#define CONTROL_TEST_MODE (1 << 4)
	60
	61	static inline bool is_power_reg(u8 reg)
	62	{
	63	return reg < LTC2945_SENSE_H;
	64	}
	65
	66	/* Return the value from the given register in uW, mV, or mA */
	67	static long long ltc2945_reg_to_val(struct device *dev, u8 reg)
	68	{
	69	struct regmap *regmap = dev_get_drvdata(dev);
70	unsigned int control;
71	u8 buf[3];
72	long long val;
73	int ret;
74
75	ret = regmap_bulk_read(regmap, reg, buf,
76	is_power_reg(reg) ? 3 : 2);
77	if (ret < 0)
78	return ret;
79
80	if (is_power_reg(reg)) {
81	/* power */
82	val = (buf[0] << 16) + (buf[1] << 8) + buf[2];
83	} else {
84	/* current, voltage */
85	val = (buf[0] << 4) + (buf[1] >> 4);
86	}
87
88	switch (reg) {
89	case LTC2945_POWER_H:
90	case LTC2945_MAX_POWER_H:
91	case LTC2945_MIN_POWER_H:
92	case LTC2945_MAX_POWER_THRES_H:
93	case LTC2945_MIN_POWER_THRES_H:
94	/*
95	* Convert to uW by assuming current is measured with
96	* an 1mOhm sense resistor, similar to current
97	* measurements.
98	* Control register bit 0 selects if voltage at SENSE+/VDD
99	* or voltage at ADIN is used to measure power.
100	*/
101	ret = regmap_read(regmap, LTC2945_CONTROL, &control);
102	if (ret < 0)
103	return ret;
104	if (control & CONTROL_MULT_SELECT) {
105	/* 25 mV * 25 uV = 0.625 uV resolution. */
106	val *= 625LL;
107	} else {
108	/* 0.5 mV * 25 uV = 0.0125 uV resolution. */
109	val = (val * 25LL) >> 1;
110	}
111	break;
112	case LTC2945_VIN_H:
113	case LTC2945_MAX_VIN_H:
114	case LTC2945_MIN_VIN_H:
115	case LTC2945_MAX_VIN_THRES_H:
116	case LTC2945_MIN_VIN_THRES_H:
117	/* 25 mV resolution. Convert to mV. */
118	val *= 25;
119	break;
120	case LTC2945_ADIN_H:
121	case LTC2945_MAX_ADIN_H:
122	case LTC2945_MIN_ADIN_THRES_H:
123	case LTC2945_MAX_ADIN_THRES_H:
124	case LTC2945_MIN_ADIN_H:
125	/* 0.5mV resolution. Convert to mV. */
126	val = val >> 1;
127	break;
128	case LTC2945_SENSE_H:
129	case LTC2945_MAX_SENSE_H:
130	case LTC2945_MIN_SENSE_H:
131	case LTC2945_MAX_SENSE_THRES_H:
132	case LTC2945_MIN_SENSE_THRES_H:
133	/*
134	* 25 uV resolution. Convert to current as measured with
135	* an 1 mOhm sense resistor, in mA. If a different sense
136	* resistor is installed, calculate the actual current by
137	* dividing the reported current by the sense resistor value
138	* in mOhm.
139	*/
140	val *= 25;
141	break;
142	default:
143	return -EINVAL;
144	}
145	return val;
146	}
147
148	static int ltc2945_val_to_reg(struct device *dev, u8 reg,
149	unsigned long val)
150	{
151	struct regmap *regmap = dev_get_drvdata(dev);
152	unsigned int control;
153	int ret;
154
155	switch (reg) {
156	case LTC2945_POWER_H:
157	case LTC2945_MAX_POWER_H:
158	case LTC2945_MIN_POWER_H:
159	case LTC2945_MAX_POWER_THRES_H:
160	case LTC2945_MIN_POWER_THRES_H:
161	/*
162	* Convert to register value by assuming current is measured
163	* with an 1mOhm sense resistor, similar to current
164	* measurements.
165	* Control register bit 0 selects if voltage at SENSE+/VDD
166	* or voltage at ADIN is used to measure power, which in turn
167	* determines register calculations.
168	*/
169	ret = regmap_read(regmap, LTC2945_CONTROL, &control);
170	if (ret < 0)
171	return ret;
172	if (control & CONTROL_MULT_SELECT) {
173	/* 25 mV * 25 uV = 0.625 uV resolution. */
174	val = DIV_ROUND_CLOSEST(val, 625);
175	} else {
176	/*
177	* 0.5 mV * 25 uV = 0.0125 uV resolution.
178	* Divide first to avoid overflow;
179	* accept loss of accuracy.
180	*/
181	val = DIV_ROUND_CLOSEST(val, 25) * 2;
182	}
183	break;
184	case LTC2945_VIN_H:
185	case LTC2945_MAX_VIN_H:
186	case LTC2945_MIN_VIN_H:
187	case LTC2945_MAX_VIN_THRES_H:
188	case LTC2945_MIN_VIN_THRES_H:
189	/* 25 mV resolution. */
190	val /= 25;
191	break;
192	case LTC2945_ADIN_H:
193	case LTC2945_MAX_ADIN_H:
194	case LTC2945_MIN_ADIN_THRES_H:
195	case LTC2945_MAX_ADIN_THRES_H:
196	case LTC2945_MIN_ADIN_H:
197	/* 0.5mV resolution. */
198	val *= 2;
199	break;
200	case LTC2945_SENSE_H:
201	case LTC2945_MAX_SENSE_H:
202	case LTC2945_MIN_SENSE_H:
203	case LTC2945_MAX_SENSE_THRES_H:
204	case LTC2945_MIN_SENSE_THRES_H:
205	/*
206	* 25 uV resolution. Convert to current as measured with
207	* an 1 mOhm sense resistor, in mA. If a different sense
208	* resistor is installed, calculate the actual current by
209	* dividing the reported current by the sense resistor value
210	* in mOhm.
211	*/
212	val = DIV_ROUND_CLOSEST(val, 25);
213	break;
214	default:
215	return -EINVAL;
216	}
217	return val;
218	}
219
5614e26d	220	static ssize_t ltc2945_value_show(struct device *dev,
6700ce03 GR	221	struct device_attribute da, char buf)
	222	{
	223	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	224	long long value;
	225
	226	value = ltc2945_reg_to_val(dev, attr->index);
	227	if (value < 0)
	228	return value;
	229	return snprintf(buf, PAGE_SIZE, "%lld\n", value);
	230	}
	231
5614e26d GR	232	static ssize_t ltc2945_value_store(struct device *dev,
	233	struct device_attribute *da,
	234	const char *buf, size_t count)
6700ce03 GR	235	{
	236	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	237	struct regmap *regmap = dev_get_drvdata(dev);
	238	u8 reg = attr->index;
	239	unsigned long val;
	240	u8 regbuf[3];
	241	int num_regs;
	242	int regval;
	243	int ret;
	244
	245	ret = kstrtoul(buf, 10, &val);
	246	if (ret)
	247	return ret;
	248
	249	/* convert to register value, then clamp and write result */
	250	regval = ltc2945_val_to_reg(dev, reg, val);
	251	if (is_power_reg(reg)) {
	252	regval = clamp_val(regval, 0, 0xffffff);
	253	regbuf[0] = regval >> 16;
	254	regbuf[1] = (regval >> 8) & 0xff;
	255	regbuf[2] = regval;
	256	num_regs = 3;
	257	} else {
	258	regval = clamp_val(regval, 0, 0xfff) << 4;
	259	regbuf[0] = regval >> 8;
	260	regbuf[1] = regval & 0xff;
	261	num_regs = 2;
	262	}
	263	ret = regmap_bulk_write(regmap, reg, regbuf, num_regs);
	264	return ret < 0 ? ret : count;
	265	}
	266
5614e26d	267	static ssize_t ltc2945_history_store(struct device *dev,
6700ce03 GR	268	struct device_attribute *da,
	269	const char *buf, size_t count)
	270	{
	271	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	272	struct regmap *regmap = dev_get_drvdata(dev);
	273	u8 reg = attr->index;
	274	int num_regs = is_power_reg(reg) ? 3 : 2;
	275	u8 buf_min[3] = { 0xff, 0xff, 0xff };
	276	u8 buf_max[3] = { 0, 0, 0 };
	277	unsigned long val;
	278	int ret;
	279
	280	ret = kstrtoul(buf, 10, &val);
	281	if (ret)
	282	return ret;
	283	if (val != 1)
	284	return -EINVAL;
	285
	286	ret = regmap_update_bits(regmap, LTC2945_CONTROL, CONTROL_TEST_MODE,
	287	CONTROL_TEST_MODE);
	288
	289	/* Reset minimum */
	290	ret = regmap_bulk_write(regmap, reg, buf_min, num_regs);
	291	if (ret)
	292	return ret;
	293
	294	switch (reg) {
	295	case LTC2945_MIN_POWER_H:
	296	reg = LTC2945_MAX_POWER_H;
	297	break;
	298	case LTC2945_MIN_SENSE_H:
	299	reg = LTC2945_MAX_SENSE_H;
	300	break;
	301	case LTC2945_MIN_VIN_H:
	302	reg = LTC2945_MAX_VIN_H;
	303	break;
	304	case LTC2945_MIN_ADIN_H:
	305	reg = LTC2945_MAX_ADIN_H;
	306	break;
	307	default:
f75d7230 GR	308	WARN_ONCE(1, "Bad register: 0x%x\n", reg);
f75d7230 GR	309	return -EINVAL;
6700ce03 GR	310	}
	311	/* Reset maximum */
	312	ret = regmap_bulk_write(regmap, reg, buf_max, num_regs);
	313
	314	/* Try resetting test mode even if there was an error */
	315	regmap_update_bits(regmap, LTC2945_CONTROL, CONTROL_TEST_MODE, 0);
	316
	317	return ret ? : count;
	318	}
	319
5614e26d	320	static ssize_t ltc2945_bool_show(struct device *dev,
6700ce03 GR	321	struct device_attribute da, char buf)
	322	{
	323	struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
	324	struct regmap *regmap = dev_get_drvdata(dev);
	325	unsigned int fault;
	326	int ret;
	327
	328	ret = regmap_read(regmap, LTC2945_FAULT, &fault);
	329	if (ret < 0)
	330	return ret;
	331
	332	fault &= attr->index;
	333	if (fault) /* Clear reported faults in chip register */
	334	regmap_update_bits(regmap, LTC2945_FAULT, attr->index, 0);
	335
	336	return snprintf(buf, PAGE_SIZE, "%d\n", !!fault);
	337	}
	338
	339	/* Input voltages */
	340
5614e26d GR	341	static SENSOR_DEVICE_ATTR_RO(in1_input, ltc2945_value, LTC2945_VIN_H);
	342	static SENSOR_DEVICE_ATTR_RW(in1_min, ltc2945_value, LTC2945_MIN_VIN_THRES_H);
	343	static SENSOR_DEVICE_ATTR_RW(in1_max, ltc2945_value, LTC2945_MAX_VIN_THRES_H);
	344	static SENSOR_DEVICE_ATTR_RO(in1_lowest, ltc2945_value, LTC2945_MIN_VIN_H);
	345	static SENSOR_DEVICE_ATTR_RO(in1_highest, ltc2945_value, LTC2945_MAX_VIN_H);
	346	static SENSOR_DEVICE_ATTR_WO(in1_reset_history, ltc2945_history,
	347	LTC2945_MIN_VIN_H);
	348
	349	static SENSOR_DEVICE_ATTR_RO(in2_input, ltc2945_value, LTC2945_ADIN_H);
	350	static SENSOR_DEVICE_ATTR_RW(in2_min, ltc2945_value, LTC2945_MIN_ADIN_THRES_H);
	351	static SENSOR_DEVICE_ATTR_RW(in2_max, ltc2945_value, LTC2945_MAX_ADIN_THRES_H);
	352	static SENSOR_DEVICE_ATTR_RO(in2_lowest, ltc2945_value, LTC2945_MIN_ADIN_H);
	353	static SENSOR_DEVICE_ATTR_RO(in2_highest, ltc2945_value, LTC2945_MAX_ADIN_H);
	354	static SENSOR_DEVICE_ATTR_WO(in2_reset_history, ltc2945_history,
	355	LTC2945_MIN_ADIN_H);
6700ce03 GR	356
	357	/* Voltage alarms */
	358
5614e26d GR	359	static SENSOR_DEVICE_ATTR_RO(in1_min_alarm, ltc2945_bool, FAULT_VIN_UV);
	360	static SENSOR_DEVICE_ATTR_RO(in1_max_alarm, ltc2945_bool, FAULT_VIN_OV);
	361	static SENSOR_DEVICE_ATTR_RO(in2_min_alarm, ltc2945_bool, FAULT_ADIN_UV);
	362	static SENSOR_DEVICE_ATTR_RO(in2_max_alarm, ltc2945_bool, FAULT_ADIN_OV);
6700ce03 GR	363
	364	/* Currents (via sense resistor) */
	365
5614e26d GR	366	static SENSOR_DEVICE_ATTR_RO(curr1_input, ltc2945_value, LTC2945_SENSE_H);
	367	static SENSOR_DEVICE_ATTR_RW(curr1_min, ltc2945_value,
	368	LTC2945_MIN_SENSE_THRES_H);
	369	static SENSOR_DEVICE_ATTR_RW(curr1_max, ltc2945_value,
	370	LTC2945_MAX_SENSE_THRES_H);
	371	static SENSOR_DEVICE_ATTR_RO(curr1_lowest, ltc2945_value, LTC2945_MIN_SENSE_H);
	372	static SENSOR_DEVICE_ATTR_RO(curr1_highest, ltc2945_value,
	373	LTC2945_MAX_SENSE_H);
	374	static SENSOR_DEVICE_ATTR_WO(curr1_reset_history, ltc2945_history,
	375	LTC2945_MIN_SENSE_H);
6700ce03 GR	376
	377	/* Current alarms */
	378
5614e26d GR	379	static SENSOR_DEVICE_ATTR_RO(curr1_min_alarm, ltc2945_bool, FAULT_SENSE_UV);
5614e26d GR	380	static SENSOR_DEVICE_ATTR_RO(curr1_max_alarm, ltc2945_bool, FAULT_SENSE_OV);
6700ce03 GR	381
	382	/* Power */
	383
5614e26d GR	384	static SENSOR_DEVICE_ATTR_RO(power1_input, ltc2945_value, LTC2945_POWER_H);
	385	static SENSOR_DEVICE_ATTR_RW(power1_min, ltc2945_value,
	386	LTC2945_MIN_POWER_THRES_H);
	387	static SENSOR_DEVICE_ATTR_RW(power1_max, ltc2945_value,
	388	LTC2945_MAX_POWER_THRES_H);
	389	static SENSOR_DEVICE_ATTR_RO(power1_input_lowest, ltc2945_value,
	390	LTC2945_MIN_POWER_H);
	391	static SENSOR_DEVICE_ATTR_RO(power1_input_highest, ltc2945_value,
	392	LTC2945_MAX_POWER_H);
	393	static SENSOR_DEVICE_ATTR_WO(power1_reset_history, ltc2945_history,
	394	LTC2945_MIN_POWER_H);
6700ce03 GR	395
	396	/* Power alarms */
	397
5614e26d GR	398	static SENSOR_DEVICE_ATTR_RO(power1_min_alarm, ltc2945_bool, FAULT_POWER_UV);
5614e26d GR	399	static SENSOR_DEVICE_ATTR_RO(power1_max_alarm, ltc2945_bool, FAULT_POWER_OV);
6700ce03 GR	400
	401	static struct attribute *ltc2945_attrs[] = {
	402	&sensor_dev_attr_in1_input.dev_attr.attr,
	403	&sensor_dev_attr_in1_min.dev_attr.attr,
	404	&sensor_dev_attr_in1_max.dev_attr.attr,
	405	&sensor_dev_attr_in1_lowest.dev_attr.attr,
	406	&sensor_dev_attr_in1_highest.dev_attr.attr,
	407	&sensor_dev_attr_in1_reset_history.dev_attr.attr,
	408	&sensor_dev_attr_in1_min_alarm.dev_attr.attr,
	409	&sensor_dev_attr_in1_max_alarm.dev_attr.attr,
	410
	411	&sensor_dev_attr_in2_input.dev_attr.attr,
	412	&sensor_dev_attr_in2_min.dev_attr.attr,
	413	&sensor_dev_attr_in2_max.dev_attr.attr,
	414	&sensor_dev_attr_in2_lowest.dev_attr.attr,
	415	&sensor_dev_attr_in2_highest.dev_attr.attr,
	416	&sensor_dev_attr_in2_reset_history.dev_attr.attr,
	417	&sensor_dev_attr_in2_min_alarm.dev_attr.attr,
	418	&sensor_dev_attr_in2_max_alarm.dev_attr.attr,
	419
	420	&sensor_dev_attr_curr1_input.dev_attr.attr,
	421	&sensor_dev_attr_curr1_min.dev_attr.attr,
	422	&sensor_dev_attr_curr1_max.dev_attr.attr,
	423	&sensor_dev_attr_curr1_lowest.dev_attr.attr,
	424	&sensor_dev_attr_curr1_highest.dev_attr.attr,
	425	&sensor_dev_attr_curr1_reset_history.dev_attr.attr,
	426	&sensor_dev_attr_curr1_min_alarm.dev_attr.attr,
	427	&sensor_dev_attr_curr1_max_alarm.dev_attr.attr,
	428
	429	&sensor_dev_attr_power1_input.dev_attr.attr,
	430	&sensor_dev_attr_power1_min.dev_attr.attr,
	431	&sensor_dev_attr_power1_max.dev_attr.attr,
	432	&sensor_dev_attr_power1_input_lowest.dev_attr.attr,
	433	&sensor_dev_attr_power1_input_highest.dev_attr.attr,
	434	&sensor_dev_attr_power1_reset_history.dev_attr.attr,
	435	&sensor_dev_attr_power1_min_alarm.dev_attr.attr,
	436	&sensor_dev_attr_power1_max_alarm.dev_attr.attr,
	437
	438	NULL,
	439	};
	440	ATTRIBUTE_GROUPS(ltc2945);
	441
034b44b4	442	static const struct regmap_config ltc2945_regmap_config = {
6700ce03 GR	443	.reg_bits = 8,
	444	.val_bits = 8,
	445	.max_register = LTC2945_MIN_ADIN_THRES_L,
	446	};
	447
67487038	448	static int ltc2945_probe(struct i2c_client *client)
6700ce03 GR	449	{
	450	struct device *dev = &client->dev;
	451	struct device *hwmon_dev;
	452	struct regmap *regmap;
	453
	454	regmap = devm_regmap_init_i2c(client, &ltc2945_regmap_config);
	455	if (IS_ERR(regmap)) {
	456	dev_err(dev, "failed to allocate register map\n");
	457	return PTR_ERR(regmap);
	458	}
	459
	460	/* Clear faults */
	461	regmap_write(regmap, LTC2945_FAULT, 0x00);
	462
	463	hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
	464	regmap,
	465	ltc2945_groups);
	466	return PTR_ERR_OR_ZERO(hwmon_dev);
	467	}
	468
	469	static const struct i2c_device_id ltc2945_id[] = {
	470	{"ltc2945", 0},
	471	{ }
	472	};
	473
	474	MODULE_DEVICE_TABLE(i2c, ltc2945_id);
	475
	476	static struct i2c_driver ltc2945_driver = {
	477	.driver = {
	478	.name = "ltc2945",
	479	},
67487038	480	.probe_new = ltc2945_probe,
6700ce03 GR	481	.id_table = ltc2945_id,
	482	};
	483
	484	module_i2c_driver(ltc2945_driver);
	485
	486	MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
	487	MODULE_DESCRIPTION("LTC2945 driver");
	488	MODULE_LICENSE("GPL");