linux/drivers/hwmon/powr1220.c
Michael Shych 9f93aa1005 hwmon: (powr1220) Add support for Lattice's POWR1014 power manager IC
This patch adds support for Lattice's POWR1014 power manager IC.
Read access to all the ADCs on the chip are supported through
the "hwmon" "sysfs" files.

The main differences of POWR1014 compared to POWR1220 are
amount of VMON input lines: 10 on POWR1014 and 12 lines on POWR1220 and
number of output control signals: 14 on POWR1014 and 20 on POWR1220.

Signed-off-by: Michael Shych <michaelsh@nvidia.com>
Reviewed-by: Vadim Pasternak <vadimp@nvidia.com>
Link: https://lore.kernel.org/r/20220118075611.10665-4-michaelsh@nvidia.com
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2022-02-27 17:03:17 -08:00

339 lines
7.2 KiB
C

// 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 *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");