linux/drivers/hwmon/ina3221.c
Ninad Malwade b8d27d2ce8 hwmon: (ina3221) Fix shunt sum critical calculation
The shunt sum critical limit register value should be left shifted
by one bit as its LSB-0 is a reserved bit.

Fixes: 2057bdfb71 ("hwmon: (ina3221) Add summation feature support")
Signed-off-by: Ninad Malwade <nmalwade@nvidia.com>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20221108044508.23463-1-nmalwade@nvidia.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2022-11-20 06:04:15 -08:00

1027 lines
26 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* INA3221 Triple Current/Voltage Monitor
*
* Copyright (C) 2016 Texas Instruments Incorporated - https://www.ti.com/
* Andrew F. Davis <afd@ti.com>
*/
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/pm_runtime.h>
#include <linux/regmap.h>
#include <linux/util_macros.h>
#define INA3221_DRIVER_NAME "ina3221"
#define INA3221_CONFIG 0x00
#define INA3221_SHUNT1 0x01
#define INA3221_BUS1 0x02
#define INA3221_SHUNT2 0x03
#define INA3221_BUS2 0x04
#define INA3221_SHUNT3 0x05
#define INA3221_BUS3 0x06
#define INA3221_CRIT1 0x07
#define INA3221_WARN1 0x08
#define INA3221_CRIT2 0x09
#define INA3221_WARN2 0x0a
#define INA3221_CRIT3 0x0b
#define INA3221_WARN3 0x0c
#define INA3221_SHUNT_SUM 0x0d
#define INA3221_CRIT_SUM 0x0e
#define INA3221_MASK_ENABLE 0x0f
#define INA3221_CONFIG_MODE_MASK GENMASK(2, 0)
#define INA3221_CONFIG_MODE_POWERDOWN 0
#define INA3221_CONFIG_MODE_SHUNT BIT(0)
#define INA3221_CONFIG_MODE_BUS BIT(1)
#define INA3221_CONFIG_MODE_CONTINUOUS BIT(2)
#define INA3221_CONFIG_VSH_CT_SHIFT 3
#define INA3221_CONFIG_VSH_CT_MASK GENMASK(5, 3)
#define INA3221_CONFIG_VSH_CT(x) (((x) & GENMASK(5, 3)) >> 3)
#define INA3221_CONFIG_VBUS_CT_SHIFT 6
#define INA3221_CONFIG_VBUS_CT_MASK GENMASK(8, 6)
#define INA3221_CONFIG_VBUS_CT(x) (((x) & GENMASK(8, 6)) >> 6)
#define INA3221_CONFIG_AVG_SHIFT 9
#define INA3221_CONFIG_AVG_MASK GENMASK(11, 9)
#define INA3221_CONFIG_AVG(x) (((x) & GENMASK(11, 9)) >> 9)
#define INA3221_CONFIG_CHs_EN_MASK GENMASK(14, 12)
#define INA3221_CONFIG_CHx_EN(x) BIT(14 - (x))
#define INA3221_MASK_ENABLE_SCC_MASK GENMASK(14, 12)
#define INA3221_CONFIG_DEFAULT 0x7127
#define INA3221_RSHUNT_DEFAULT 10000
enum ina3221_fields {
/* Configuration */
F_RST,
/* Status Flags */
F_CVRF,
/* Warning Flags */
F_WF3, F_WF2, F_WF1,
/* Alert Flags: SF is the summation-alert flag */
F_SF, F_CF3, F_CF2, F_CF1,
/* sentinel */
F_MAX_FIELDS
};
static const struct reg_field ina3221_reg_fields[] = {
[F_RST] = REG_FIELD(INA3221_CONFIG, 15, 15),
[F_CVRF] = REG_FIELD(INA3221_MASK_ENABLE, 0, 0),
[F_WF3] = REG_FIELD(INA3221_MASK_ENABLE, 3, 3),
[F_WF2] = REG_FIELD(INA3221_MASK_ENABLE, 4, 4),
[F_WF1] = REG_FIELD(INA3221_MASK_ENABLE, 5, 5),
[F_SF] = REG_FIELD(INA3221_MASK_ENABLE, 6, 6),
[F_CF3] = REG_FIELD(INA3221_MASK_ENABLE, 7, 7),
[F_CF2] = REG_FIELD(INA3221_MASK_ENABLE, 8, 8),
[F_CF1] = REG_FIELD(INA3221_MASK_ENABLE, 9, 9),
};
enum ina3221_channels {
INA3221_CHANNEL1,
INA3221_CHANNEL2,
INA3221_CHANNEL3,
INA3221_NUM_CHANNELS
};
/**
* struct ina3221_input - channel input source specific information
* @label: label of channel input source
* @shunt_resistor: shunt resistor value of channel input source
* @disconnected: connection status of channel input source
*/
struct ina3221_input {
const char *label;
int shunt_resistor;
bool disconnected;
};
/**
* struct ina3221_data - device specific information
* @pm_dev: Device pointer for pm runtime
* @regmap: Register map of the device
* @fields: Register fields of the device
* @inputs: Array of channel input source specific structures
* @lock: mutex lock to serialize sysfs attribute accesses
* @reg_config: Register value of INA3221_CONFIG
* @summation_shunt_resistor: equivalent shunt resistor value for summation
* @single_shot: running in single-shot operating mode
*/
struct ina3221_data {
struct device *pm_dev;
struct regmap *regmap;
struct regmap_field *fields[F_MAX_FIELDS];
struct ina3221_input inputs[INA3221_NUM_CHANNELS];
struct mutex lock;
u32 reg_config;
int summation_shunt_resistor;
bool single_shot;
};
static inline bool ina3221_is_enabled(struct ina3221_data *ina, int channel)
{
/* Summation channel checks shunt resistor values */
if (channel > INA3221_CHANNEL3)
return ina->summation_shunt_resistor != 0;
return pm_runtime_active(ina->pm_dev) &&
(ina->reg_config & INA3221_CONFIG_CHx_EN(channel));
}
/*
* Helper function to return the resistor value for current summation.
*
* There is a condition to calculate current summation -- all the shunt
* resistor values should be the same, so as to simply fit the formula:
* current summation = shunt voltage summation / shunt resistor
*
* Returns the equivalent shunt resistor value on success or 0 on failure
*/
static inline int ina3221_summation_shunt_resistor(struct ina3221_data *ina)
{
struct ina3221_input *input = ina->inputs;
int i, shunt_resistor = 0;
for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
if (input[i].disconnected || !input[i].shunt_resistor)
continue;
if (!shunt_resistor) {
/* Found the reference shunt resistor value */
shunt_resistor = input[i].shunt_resistor;
} else {
/* No summation if resistor values are different */
if (shunt_resistor != input[i].shunt_resistor)
return 0;
}
}
return shunt_resistor;
}
/* Lookup table for Bus and Shunt conversion times in usec */
static const u16 ina3221_conv_time[] = {
140, 204, 332, 588, 1100, 2116, 4156, 8244,
};
/* Lookup table for number of samples using in averaging mode */
static const int ina3221_avg_samples[] = {
1, 4, 16, 64, 128, 256, 512, 1024,
};
/* Converting update_interval in msec to conversion time in usec */
static inline u32 ina3221_interval_ms_to_conv_time(u16 config, int interval)
{
u32 channels = hweight16(config & INA3221_CONFIG_CHs_EN_MASK);
u32 samples_idx = INA3221_CONFIG_AVG(config);
u32 samples = ina3221_avg_samples[samples_idx];
/* Bisect the result to Bus and Shunt conversion times */
return DIV_ROUND_CLOSEST(interval * 1000 / 2, channels * samples);
}
/* Converting CONFIG register value to update_interval in usec */
static inline u32 ina3221_reg_to_interval_us(u16 config)
{
u32 channels = hweight16(config & INA3221_CONFIG_CHs_EN_MASK);
u32 vbus_ct_idx = INA3221_CONFIG_VBUS_CT(config);
u32 vsh_ct_idx = INA3221_CONFIG_VSH_CT(config);
u32 vbus_ct = ina3221_conv_time[vbus_ct_idx];
u32 vsh_ct = ina3221_conv_time[vsh_ct_idx];
/* Calculate total conversion time */
return channels * (vbus_ct + vsh_ct);
}
static inline int ina3221_wait_for_data(struct ina3221_data *ina)
{
u32 wait, cvrf;
wait = ina3221_reg_to_interval_us(ina->reg_config);
/* Polling the CVRF bit to make sure read data is ready */
return regmap_field_read_poll_timeout(ina->fields[F_CVRF],
cvrf, cvrf, wait, wait * 2);
}
static int ina3221_read_value(struct ina3221_data *ina, unsigned int reg,
int *val)
{
unsigned int regval;
int ret;
ret = regmap_read(ina->regmap, reg, &regval);
if (ret)
return ret;
/*
* Shunt Voltage Sum register has 14-bit value with 1-bit shift
* Other Shunt Voltage registers have 12 bits with 3-bit shift
*/
if (reg == INA3221_SHUNT_SUM || reg == INA3221_CRIT_SUM)
*val = sign_extend32(regval >> 1, 14);
else
*val = sign_extend32(regval >> 3, 12);
return 0;
}
static const u8 ina3221_in_reg[] = {
INA3221_BUS1,
INA3221_BUS2,
INA3221_BUS3,
INA3221_SHUNT1,
INA3221_SHUNT2,
INA3221_SHUNT3,
INA3221_SHUNT_SUM,
};
static int ina3221_read_chip(struct device *dev, u32 attr, long *val)
{
struct ina3221_data *ina = dev_get_drvdata(dev);
int regval;
switch (attr) {
case hwmon_chip_samples:
regval = INA3221_CONFIG_AVG(ina->reg_config);
*val = ina3221_avg_samples[regval];
return 0;
case hwmon_chip_update_interval:
/* Return in msec */
*val = ina3221_reg_to_interval_us(ina->reg_config);
*val = DIV_ROUND_CLOSEST(*val, 1000);
return 0;
default:
return -EOPNOTSUPP;
}
}
static int ina3221_read_in(struct device *dev, u32 attr, int channel, long *val)
{
const bool is_shunt = channel > INA3221_CHANNEL3;
struct ina3221_data *ina = dev_get_drvdata(dev);
u8 reg = ina3221_in_reg[channel];
int regval, ret;
/*
* Translate shunt channel index to sensor channel index except
* the 7th channel (6 since being 0-aligned) is for summation.
*/
if (channel != 6)
channel %= INA3221_NUM_CHANNELS;
switch (attr) {
case hwmon_in_input:
if (!ina3221_is_enabled(ina, channel))
return -ENODATA;
/* Write CONFIG register to trigger a single-shot measurement */
if (ina->single_shot) {
regmap_write(ina->regmap, INA3221_CONFIG,
ina->reg_config);
ret = ina3221_wait_for_data(ina);
if (ret)
return ret;
}
ret = ina3221_read_value(ina, reg, &regval);
if (ret)
return ret;
/*
* Scale of shunt voltage (uV): LSB is 40uV
* Scale of bus voltage (mV): LSB is 8mV
*/
*val = regval * (is_shunt ? 40 : 8);
return 0;
case hwmon_in_enable:
*val = ina3221_is_enabled(ina, channel);
return 0;
default:
return -EOPNOTSUPP;
}
}
static const u8 ina3221_curr_reg[][INA3221_NUM_CHANNELS + 1] = {
[hwmon_curr_input] = { INA3221_SHUNT1, INA3221_SHUNT2,
INA3221_SHUNT3, INA3221_SHUNT_SUM },
[hwmon_curr_max] = { INA3221_WARN1, INA3221_WARN2, INA3221_WARN3, 0 },
[hwmon_curr_crit] = { INA3221_CRIT1, INA3221_CRIT2,
INA3221_CRIT3, INA3221_CRIT_SUM },
[hwmon_curr_max_alarm] = { F_WF1, F_WF2, F_WF3, 0 },
[hwmon_curr_crit_alarm] = { F_CF1, F_CF2, F_CF3, F_SF },
};
static int ina3221_read_curr(struct device *dev, u32 attr,
int channel, long *val)
{
struct ina3221_data *ina = dev_get_drvdata(dev);
struct ina3221_input *input = ina->inputs;
u8 reg = ina3221_curr_reg[attr][channel];
int resistance_uo, voltage_nv;
int regval, ret;
if (channel > INA3221_CHANNEL3)
resistance_uo = ina->summation_shunt_resistor;
else
resistance_uo = input[channel].shunt_resistor;
switch (attr) {
case hwmon_curr_input:
if (!ina3221_is_enabled(ina, channel))
return -ENODATA;
/* Write CONFIG register to trigger a single-shot measurement */
if (ina->single_shot) {
regmap_write(ina->regmap, INA3221_CONFIG,
ina->reg_config);
ret = ina3221_wait_for_data(ina);
if (ret)
return ret;
}
fallthrough;
case hwmon_curr_crit:
case hwmon_curr_max:
if (!resistance_uo)
return -ENODATA;
ret = ina3221_read_value(ina, reg, &regval);
if (ret)
return ret;
/* Scale of shunt voltage: LSB is 40uV (40000nV) */
voltage_nv = regval * 40000;
/* Return current in mA */
*val = DIV_ROUND_CLOSEST(voltage_nv, resistance_uo);
return 0;
case hwmon_curr_crit_alarm:
case hwmon_curr_max_alarm:
/* No actual register read if channel is disabled */
if (!ina3221_is_enabled(ina, channel)) {
/* Return 0 for alert flags */
*val = 0;
return 0;
}
ret = regmap_field_read(ina->fields[reg], &regval);
if (ret)
return ret;
*val = regval;
return 0;
default:
return -EOPNOTSUPP;
}
}
static int ina3221_write_chip(struct device *dev, u32 attr, long val)
{
struct ina3221_data *ina = dev_get_drvdata(dev);
int ret, idx;
u32 tmp;
switch (attr) {
case hwmon_chip_samples:
idx = find_closest(val, ina3221_avg_samples,
ARRAY_SIZE(ina3221_avg_samples));
tmp = (ina->reg_config & ~INA3221_CONFIG_AVG_MASK) |
(idx << INA3221_CONFIG_AVG_SHIFT);
ret = regmap_write(ina->regmap, INA3221_CONFIG, tmp);
if (ret)
return ret;
/* Update reg_config accordingly */
ina->reg_config = tmp;
return 0;
case hwmon_chip_update_interval:
tmp = ina3221_interval_ms_to_conv_time(ina->reg_config, val);
idx = find_closest(tmp, ina3221_conv_time,
ARRAY_SIZE(ina3221_conv_time));
/* Update Bus and Shunt voltage conversion times */
tmp = INA3221_CONFIG_VBUS_CT_MASK | INA3221_CONFIG_VSH_CT_MASK;
tmp = (ina->reg_config & ~tmp) |
(idx << INA3221_CONFIG_VBUS_CT_SHIFT) |
(idx << INA3221_CONFIG_VSH_CT_SHIFT);
ret = regmap_write(ina->regmap, INA3221_CONFIG, tmp);
if (ret)
return ret;
/* Update reg_config accordingly */
ina->reg_config = tmp;
return 0;
default:
return -EOPNOTSUPP;
}
}
static int ina3221_write_curr(struct device *dev, u32 attr,
int channel, long val)
{
struct ina3221_data *ina = dev_get_drvdata(dev);
struct ina3221_input *input = ina->inputs;
u8 reg = ina3221_curr_reg[attr][channel];
int resistance_uo, current_ma, voltage_uv;
int regval;
if (channel > INA3221_CHANNEL3)
resistance_uo = ina->summation_shunt_resistor;
else
resistance_uo = input[channel].shunt_resistor;
if (!resistance_uo)
return -EOPNOTSUPP;
/* clamp current */
current_ma = clamp_val(val,
INT_MIN / resistance_uo,
INT_MAX / resistance_uo);
voltage_uv = DIV_ROUND_CLOSEST(current_ma * resistance_uo, 1000);
/* clamp voltage */
voltage_uv = clamp_val(voltage_uv, -163800, 163800);
/*
* Formula to convert voltage_uv to register value:
* regval = (voltage_uv / scale) << shift
* Note:
* The scale is 40uV for all shunt voltage registers
* Shunt Voltage Sum register left-shifts 1 bit
* All other Shunt Voltage registers shift 3 bits
* Results:
* SHUNT_SUM: (1 / 40uV) << 1 = 1 / 20uV
* SHUNT[1-3]: (1 / 40uV) << 3 = 1 / 5uV
*/
if (reg == INA3221_SHUNT_SUM || reg == INA3221_CRIT_SUM)
regval = DIV_ROUND_CLOSEST(voltage_uv, 20) & 0xfffe;
else
regval = DIV_ROUND_CLOSEST(voltage_uv, 5) & 0xfff8;
return regmap_write(ina->regmap, reg, regval);
}
static int ina3221_write_enable(struct device *dev, int channel, bool enable)
{
struct ina3221_data *ina = dev_get_drvdata(dev);
u16 config, mask = INA3221_CONFIG_CHx_EN(channel);
u16 config_old = ina->reg_config & mask;
u32 tmp;
int ret;
config = enable ? mask : 0;
/* Bypass if enable status is not being changed */
if (config_old == config)
return 0;
/* For enabling routine, increase refcount and resume() at first */
if (enable) {
ret = pm_runtime_resume_and_get(ina->pm_dev);
if (ret < 0) {
dev_err(dev, "Failed to get PM runtime\n");
return ret;
}
}
/* Enable or disable the channel */
tmp = (ina->reg_config & ~mask) | (config & mask);
ret = regmap_write(ina->regmap, INA3221_CONFIG, tmp);
if (ret)
goto fail;
/* Cache the latest config register value */
ina->reg_config = tmp;
/* For disabling routine, decrease refcount or suspend() at last */
if (!enable)
pm_runtime_put_sync(ina->pm_dev);
return 0;
fail:
if (enable) {
dev_err(dev, "Failed to enable channel %d: error %d\n",
channel, ret);
pm_runtime_put_sync(ina->pm_dev);
}
return ret;
}
static int ina3221_read(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long *val)
{
struct ina3221_data *ina = dev_get_drvdata(dev);
int ret;
mutex_lock(&ina->lock);
switch (type) {
case hwmon_chip:
ret = ina3221_read_chip(dev, attr, val);
break;
case hwmon_in:
/* 0-align channel ID */
ret = ina3221_read_in(dev, attr, channel - 1, val);
break;
case hwmon_curr:
ret = ina3221_read_curr(dev, attr, channel, val);
break;
default:
ret = -EOPNOTSUPP;
break;
}
mutex_unlock(&ina->lock);
return ret;
}
static int ina3221_write(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long val)
{
struct ina3221_data *ina = dev_get_drvdata(dev);
int ret;
mutex_lock(&ina->lock);
switch (type) {
case hwmon_chip:
ret = ina3221_write_chip(dev, attr, val);
break;
case hwmon_in:
/* 0-align channel ID */
ret = ina3221_write_enable(dev, channel - 1, val);
break;
case hwmon_curr:
ret = ina3221_write_curr(dev, attr, channel, val);
break;
default:
ret = -EOPNOTSUPP;
break;
}
mutex_unlock(&ina->lock);
return ret;
}
static int ina3221_read_string(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, const char **str)
{
struct ina3221_data *ina = dev_get_drvdata(dev);
int index = channel - 1;
if (channel == 7)
*str = "sum of shunt voltages";
else
*str = ina->inputs[index].label;
return 0;
}
static umode_t ina3221_is_visible(const void *drvdata,
enum hwmon_sensor_types type,
u32 attr, int channel)
{
const struct ina3221_data *ina = drvdata;
const struct ina3221_input *input = NULL;
switch (type) {
case hwmon_chip:
switch (attr) {
case hwmon_chip_samples:
case hwmon_chip_update_interval:
return 0644;
default:
return 0;
}
case hwmon_in:
/* Ignore in0_ */
if (channel == 0)
return 0;
switch (attr) {
case hwmon_in_label:
if (channel - 1 <= INA3221_CHANNEL3)
input = &ina->inputs[channel - 1];
else if (channel == 7)
return 0444;
/* Hide label node if label is not provided */
return (input && input->label) ? 0444 : 0;
case hwmon_in_input:
return 0444;
case hwmon_in_enable:
return 0644;
default:
return 0;
}
case hwmon_curr:
switch (attr) {
case hwmon_curr_input:
case hwmon_curr_crit_alarm:
case hwmon_curr_max_alarm:
return 0444;
case hwmon_curr_crit:
case hwmon_curr_max:
return 0644;
default:
return 0;
}
default:
return 0;
}
}
#define INA3221_HWMON_CURR_CONFIG (HWMON_C_INPUT | \
HWMON_C_CRIT | HWMON_C_CRIT_ALARM | \
HWMON_C_MAX | HWMON_C_MAX_ALARM)
static const struct hwmon_channel_info *ina3221_info[] = {
HWMON_CHANNEL_INFO(chip,
HWMON_C_SAMPLES,
HWMON_C_UPDATE_INTERVAL),
HWMON_CHANNEL_INFO(in,
/* 0: dummy, skipped in is_visible */
HWMON_I_INPUT,
/* 1-3: input voltage Channels */
HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
HWMON_I_INPUT | HWMON_I_ENABLE | HWMON_I_LABEL,
/* 4-6: shunt voltage Channels */
HWMON_I_INPUT,
HWMON_I_INPUT,
HWMON_I_INPUT,
/* 7: summation of shunt voltage channels */
HWMON_I_INPUT | HWMON_I_LABEL),
HWMON_CHANNEL_INFO(curr,
/* 1-3: current channels*/
INA3221_HWMON_CURR_CONFIG,
INA3221_HWMON_CURR_CONFIG,
INA3221_HWMON_CURR_CONFIG,
/* 4: summation of current channels */
HWMON_C_INPUT | HWMON_C_CRIT | HWMON_C_CRIT_ALARM),
NULL
};
static const struct hwmon_ops ina3221_hwmon_ops = {
.is_visible = ina3221_is_visible,
.read_string = ina3221_read_string,
.read = ina3221_read,
.write = ina3221_write,
};
static const struct hwmon_chip_info ina3221_chip_info = {
.ops = &ina3221_hwmon_ops,
.info = ina3221_info,
};
/* Extra attribute groups */
static ssize_t ina3221_shunt_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
struct ina3221_data *ina = dev_get_drvdata(dev);
unsigned int channel = sd_attr->index;
struct ina3221_input *input = &ina->inputs[channel];
return sysfs_emit(buf, "%d\n", input->shunt_resistor);
}
static ssize_t ina3221_shunt_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct sensor_device_attribute *sd_attr = to_sensor_dev_attr(attr);
struct ina3221_data *ina = dev_get_drvdata(dev);
unsigned int channel = sd_attr->index;
struct ina3221_input *input = &ina->inputs[channel];
int val;
int ret;
ret = kstrtoint(buf, 0, &val);
if (ret)
return ret;
val = clamp_val(val, 1, INT_MAX);
input->shunt_resistor = val;
/* Update summation_shunt_resistor for summation channel */
ina->summation_shunt_resistor = ina3221_summation_shunt_resistor(ina);
return count;
}
/* shunt resistance */
static SENSOR_DEVICE_ATTR_RW(shunt1_resistor, ina3221_shunt, INA3221_CHANNEL1);
static SENSOR_DEVICE_ATTR_RW(shunt2_resistor, ina3221_shunt, INA3221_CHANNEL2);
static SENSOR_DEVICE_ATTR_RW(shunt3_resistor, ina3221_shunt, INA3221_CHANNEL3);
static struct attribute *ina3221_attrs[] = {
&sensor_dev_attr_shunt1_resistor.dev_attr.attr,
&sensor_dev_attr_shunt2_resistor.dev_attr.attr,
&sensor_dev_attr_shunt3_resistor.dev_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(ina3221);
static const struct regmap_range ina3221_yes_ranges[] = {
regmap_reg_range(INA3221_CONFIG, INA3221_BUS3),
regmap_reg_range(INA3221_SHUNT_SUM, INA3221_SHUNT_SUM),
regmap_reg_range(INA3221_MASK_ENABLE, INA3221_MASK_ENABLE),
};
static const struct regmap_access_table ina3221_volatile_table = {
.yes_ranges = ina3221_yes_ranges,
.n_yes_ranges = ARRAY_SIZE(ina3221_yes_ranges),
};
static const struct regmap_config ina3221_regmap_config = {
.reg_bits = 8,
.val_bits = 16,
.cache_type = REGCACHE_RBTREE,
.volatile_table = &ina3221_volatile_table,
};
static int ina3221_probe_child_from_dt(struct device *dev,
struct device_node *child,
struct ina3221_data *ina)
{
struct ina3221_input *input;
u32 val;
int ret;
ret = of_property_read_u32(child, "reg", &val);
if (ret) {
dev_err(dev, "missing reg property of %pOFn\n", child);
return ret;
} else if (val > INA3221_CHANNEL3) {
dev_err(dev, "invalid reg %d of %pOFn\n", val, child);
return ret;
}
input = &ina->inputs[val];
/* Log the disconnected channel input */
if (!of_device_is_available(child)) {
input->disconnected = true;
return 0;
}
/* Save the connected input label if available */
of_property_read_string(child, "label", &input->label);
/* Overwrite default shunt resistor value optionally */
if (!of_property_read_u32(child, "shunt-resistor-micro-ohms", &val)) {
if (val < 1 || val > INT_MAX) {
dev_err(dev, "invalid shunt resistor value %u of %pOFn\n",
val, child);
return -EINVAL;
}
input->shunt_resistor = val;
}
return 0;
}
static int ina3221_probe_from_dt(struct device *dev, struct ina3221_data *ina)
{
const struct device_node *np = dev->of_node;
struct device_node *child;
int ret;
/* Compatible with non-DT platforms */
if (!np)
return 0;
ina->single_shot = of_property_read_bool(np, "ti,single-shot");
for_each_child_of_node(np, child) {
ret = ina3221_probe_child_from_dt(dev, child, ina);
if (ret) {
of_node_put(child);
return ret;
}
}
return 0;
}
static int ina3221_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct ina3221_data *ina;
struct device *hwmon_dev;
int i, ret;
ina = devm_kzalloc(dev, sizeof(*ina), GFP_KERNEL);
if (!ina)
return -ENOMEM;
ina->regmap = devm_regmap_init_i2c(client, &ina3221_regmap_config);
if (IS_ERR(ina->regmap)) {
dev_err(dev, "Unable to allocate register map\n");
return PTR_ERR(ina->regmap);
}
for (i = 0; i < F_MAX_FIELDS; i++) {
ina->fields[i] = devm_regmap_field_alloc(dev,
ina->regmap,
ina3221_reg_fields[i]);
if (IS_ERR(ina->fields[i])) {
dev_err(dev, "Unable to allocate regmap fields\n");
return PTR_ERR(ina->fields[i]);
}
}
for (i = 0; i < INA3221_NUM_CHANNELS; i++)
ina->inputs[i].shunt_resistor = INA3221_RSHUNT_DEFAULT;
ret = ina3221_probe_from_dt(dev, ina);
if (ret) {
dev_err(dev, "Unable to probe from device tree\n");
return ret;
}
/* The driver will be reset, so use reset value */
ina->reg_config = INA3221_CONFIG_DEFAULT;
/* Clear continuous bit to use single-shot mode */
if (ina->single_shot)
ina->reg_config &= ~INA3221_CONFIG_MODE_CONTINUOUS;
/* Disable channels if their inputs are disconnected */
for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
if (ina->inputs[i].disconnected)
ina->reg_config &= ~INA3221_CONFIG_CHx_EN(i);
}
/* Initialize summation_shunt_resistor for summation channel control */
ina->summation_shunt_resistor = ina3221_summation_shunt_resistor(ina);
ina->pm_dev = dev;
mutex_init(&ina->lock);
dev_set_drvdata(dev, ina);
/* Enable PM runtime -- status is suspended by default */
pm_runtime_enable(ina->pm_dev);
/* Initialize (resume) the device */
for (i = 0; i < INA3221_NUM_CHANNELS; i++) {
if (ina->inputs[i].disconnected)
continue;
/* Match the refcount with number of enabled channels */
ret = pm_runtime_get_sync(ina->pm_dev);
if (ret < 0)
goto fail;
}
hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, ina,
&ina3221_chip_info,
ina3221_groups);
if (IS_ERR(hwmon_dev)) {
dev_err(dev, "Unable to register hwmon device\n");
ret = PTR_ERR(hwmon_dev);
goto fail;
}
return 0;
fail:
pm_runtime_disable(ina->pm_dev);
pm_runtime_set_suspended(ina->pm_dev);
/* pm_runtime_put_noidle() will decrease the PM refcount until 0 */
for (i = 0; i < INA3221_NUM_CHANNELS; i++)
pm_runtime_put_noidle(ina->pm_dev);
mutex_destroy(&ina->lock);
return ret;
}
static void ina3221_remove(struct i2c_client *client)
{
struct ina3221_data *ina = dev_get_drvdata(&client->dev);
int i;
pm_runtime_disable(ina->pm_dev);
pm_runtime_set_suspended(ina->pm_dev);
/* pm_runtime_put_noidle() will decrease the PM refcount until 0 */
for (i = 0; i < INA3221_NUM_CHANNELS; i++)
pm_runtime_put_noidle(ina->pm_dev);
mutex_destroy(&ina->lock);
}
static int ina3221_suspend(struct device *dev)
{
struct ina3221_data *ina = dev_get_drvdata(dev);
int ret;
/* Save config register value and enable cache-only */
ret = regmap_read(ina->regmap, INA3221_CONFIG, &ina->reg_config);
if (ret)
return ret;
/* Set to power-down mode for power saving */
ret = regmap_update_bits(ina->regmap, INA3221_CONFIG,
INA3221_CONFIG_MODE_MASK,
INA3221_CONFIG_MODE_POWERDOWN);
if (ret)
return ret;
regcache_cache_only(ina->regmap, true);
regcache_mark_dirty(ina->regmap);
return 0;
}
static int ina3221_resume(struct device *dev)
{
struct ina3221_data *ina = dev_get_drvdata(dev);
int ret;
regcache_cache_only(ina->regmap, false);
/* Software reset the chip */
ret = regmap_field_write(ina->fields[F_RST], true);
if (ret) {
dev_err(dev, "Unable to reset device\n");
return ret;
}
/* Restore cached register values to hardware */
ret = regcache_sync(ina->regmap);
if (ret)
return ret;
/* Restore config register value to hardware */
ret = regmap_write(ina->regmap, INA3221_CONFIG, ina->reg_config);
if (ret)
return ret;
/* Initialize summation channel control */
if (ina->summation_shunt_resistor) {
/*
* Take all three channels into summation by default
* Shunt measurements of disconnected channels should
* be 0, so it does not matter for summation.
*/
ret = regmap_update_bits(ina->regmap, INA3221_MASK_ENABLE,
INA3221_MASK_ENABLE_SCC_MASK,
INA3221_MASK_ENABLE_SCC_MASK);
if (ret) {
dev_err(dev, "Unable to control summation channel\n");
return ret;
}
}
return 0;
}
static DEFINE_RUNTIME_DEV_PM_OPS(ina3221_pm, ina3221_suspend, ina3221_resume,
NULL);
static const struct of_device_id ina3221_of_match_table[] = {
{ .compatible = "ti,ina3221", },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, ina3221_of_match_table);
static const struct i2c_device_id ina3221_ids[] = {
{ "ina3221", 0 },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(i2c, ina3221_ids);
static struct i2c_driver ina3221_i2c_driver = {
.probe_new = ina3221_probe,
.remove = ina3221_remove,
.driver = {
.name = INA3221_DRIVER_NAME,
.of_match_table = ina3221_of_match_table,
.pm = pm_ptr(&ina3221_pm),
},
.id_table = ina3221_ids,
};
module_i2c_driver(ina3221_i2c_driver);
MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
MODULE_DESCRIPTION("Texas Instruments INA3221 HWMon Driver");
MODULE_LICENSE("GPL v2");