mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-15 16:53:54 +08:00
034b44b4a2
Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
238 lines
6.8 KiB
C
238 lines
6.8 KiB
C
/*
|
|
* Driver for Linear Technology LTC4222 Dual Hot Swap controller
|
|
*
|
|
* Copyright (c) 2014 Guenter Roeck
|
|
*
|
|
* 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/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/err.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/bitops.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 LTC4222_CONTROL1 0xd0
|
|
#define LTC4222_ALERT1 0xd1
|
|
#define LTC4222_STATUS1 0xd2
|
|
#define LTC4222_FAULT1 0xd3
|
|
#define LTC4222_CONTROL2 0xd4
|
|
#define LTC4222_ALERT2 0xd5
|
|
#define LTC4222_STATUS2 0xd6
|
|
#define LTC4222_FAULT2 0xd7
|
|
#define LTC4222_SOURCE1 0xd8
|
|
#define LTC4222_SOURCE2 0xda
|
|
#define LTC4222_ADIN1 0xdc
|
|
#define LTC4222_ADIN2 0xde
|
|
#define LTC4222_SENSE1 0xe0
|
|
#define LTC4222_SENSE2 0xe2
|
|
#define LTC4222_ADC_CONTROL 0xe4
|
|
|
|
/*
|
|
* Fault register bits
|
|
*/
|
|
#define FAULT_OV BIT(0)
|
|
#define FAULT_UV BIT(1)
|
|
#define FAULT_OC BIT(2)
|
|
#define FAULT_POWER_BAD BIT(3)
|
|
#define FAULT_FET_BAD BIT(5)
|
|
|
|
/* Return the voltage from the given register in mV or mA */
|
|
static int ltc4222_get_value(struct device *dev, u8 reg)
|
|
{
|
|
struct regmap *regmap = dev_get_drvdata(dev);
|
|
unsigned int val;
|
|
u8 buf[2];
|
|
int ret;
|
|
|
|
ret = regmap_bulk_read(regmap, reg, buf, 2);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
val = ((buf[0] << 8) + buf[1]) >> 6;
|
|
|
|
switch (reg) {
|
|
case LTC4222_ADIN1:
|
|
case LTC4222_ADIN2:
|
|
/* 1.25 mV resolution. Convert to mV. */
|
|
val = DIV_ROUND_CLOSEST(val * 5, 4);
|
|
break;
|
|
case LTC4222_SOURCE1:
|
|
case LTC4222_SOURCE2:
|
|
/* 31.25 mV resolution. Convert to mV. */
|
|
val = DIV_ROUND_CLOSEST(val * 125, 4);
|
|
break;
|
|
case LTC4222_SENSE1:
|
|
case LTC4222_SENSE2:
|
|
/*
|
|
* 62.5 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 * 125, 2);
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
return val;
|
|
}
|
|
|
|
static ssize_t ltc4222_show_value(struct device *dev,
|
|
struct device_attribute *da, char *buf)
|
|
{
|
|
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
|
|
int value;
|
|
|
|
value = ltc4222_get_value(dev, attr->index);
|
|
if (value < 0)
|
|
return value;
|
|
return snprintf(buf, PAGE_SIZE, "%d\n", value);
|
|
}
|
|
|
|
static ssize_t ltc4222_show_bool(struct device *dev,
|
|
struct device_attribute *da, char *buf)
|
|
{
|
|
struct sensor_device_attribute_2 *attr = to_sensor_dev_attr_2(da);
|
|
struct regmap *regmap = dev_get_drvdata(dev);
|
|
unsigned int fault;
|
|
int ret;
|
|
|
|
ret = regmap_read(regmap, attr->nr, &fault);
|
|
if (ret < 0)
|
|
return ret;
|
|
fault &= attr->index;
|
|
if (fault) /* Clear reported faults in chip register */
|
|
regmap_update_bits(regmap, attr->nr, attr->index, 0);
|
|
|
|
return snprintf(buf, PAGE_SIZE, "%d\n", !!fault);
|
|
}
|
|
|
|
/* Voltages */
|
|
static SENSOR_DEVICE_ATTR(in1_input, S_IRUGO, ltc4222_show_value, NULL,
|
|
LTC4222_SOURCE1);
|
|
static SENSOR_DEVICE_ATTR(in2_input, S_IRUGO, ltc4222_show_value, NULL,
|
|
LTC4222_ADIN1);
|
|
static SENSOR_DEVICE_ATTR(in3_input, S_IRUGO, ltc4222_show_value, NULL,
|
|
LTC4222_SOURCE2);
|
|
static SENSOR_DEVICE_ATTR(in4_input, S_IRUGO, ltc4222_show_value, NULL,
|
|
LTC4222_ADIN2);
|
|
|
|
/*
|
|
* Voltage alarms
|
|
* UV/OV faults are associated with the input voltage, and power bad and fet
|
|
* faults are associated with the output voltage.
|
|
*/
|
|
static SENSOR_DEVICE_ATTR_2(in1_min_alarm, S_IRUGO, ltc4222_show_bool, NULL,
|
|
LTC4222_FAULT1, FAULT_UV);
|
|
static SENSOR_DEVICE_ATTR_2(in1_max_alarm, S_IRUGO, ltc4222_show_bool, NULL,
|
|
LTC4222_FAULT1, FAULT_OV);
|
|
static SENSOR_DEVICE_ATTR_2(in2_alarm, S_IRUGO, ltc4222_show_bool, NULL,
|
|
LTC4222_FAULT1, FAULT_POWER_BAD | FAULT_FET_BAD);
|
|
|
|
static SENSOR_DEVICE_ATTR_2(in3_min_alarm, S_IRUGO, ltc4222_show_bool, NULL,
|
|
LTC4222_FAULT2, FAULT_UV);
|
|
static SENSOR_DEVICE_ATTR_2(in3_max_alarm, S_IRUGO, ltc4222_show_bool, NULL,
|
|
LTC4222_FAULT2, FAULT_OV);
|
|
static SENSOR_DEVICE_ATTR_2(in4_alarm, S_IRUGO, ltc4222_show_bool, NULL,
|
|
LTC4222_FAULT2, FAULT_POWER_BAD | FAULT_FET_BAD);
|
|
|
|
/* Current (via sense resistor) */
|
|
static SENSOR_DEVICE_ATTR(curr1_input, S_IRUGO, ltc4222_show_value, NULL,
|
|
LTC4222_SENSE1);
|
|
static SENSOR_DEVICE_ATTR(curr2_input, S_IRUGO, ltc4222_show_value, NULL,
|
|
LTC4222_SENSE2);
|
|
|
|
/* Overcurrent alarm */
|
|
static SENSOR_DEVICE_ATTR_2(curr1_max_alarm, S_IRUGO, ltc4222_show_bool, NULL,
|
|
LTC4222_FAULT1, FAULT_OC);
|
|
static SENSOR_DEVICE_ATTR_2(curr2_max_alarm, S_IRUGO, ltc4222_show_bool, NULL,
|
|
LTC4222_FAULT2, FAULT_OC);
|
|
|
|
static struct attribute *ltc4222_attrs[] = {
|
|
&sensor_dev_attr_in1_input.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_alarm.dev_attr.attr,
|
|
&sensor_dev_attr_in3_input.dev_attr.attr,
|
|
&sensor_dev_attr_in3_min_alarm.dev_attr.attr,
|
|
&sensor_dev_attr_in3_max_alarm.dev_attr.attr,
|
|
&sensor_dev_attr_in4_input.dev_attr.attr,
|
|
&sensor_dev_attr_in4_alarm.dev_attr.attr,
|
|
|
|
&sensor_dev_attr_curr1_input.dev_attr.attr,
|
|
&sensor_dev_attr_curr1_max_alarm.dev_attr.attr,
|
|
&sensor_dev_attr_curr2_input.dev_attr.attr,
|
|
&sensor_dev_attr_curr2_max_alarm.dev_attr.attr,
|
|
|
|
NULL,
|
|
};
|
|
ATTRIBUTE_GROUPS(ltc4222);
|
|
|
|
static const struct regmap_config ltc4222_regmap_config = {
|
|
.reg_bits = 8,
|
|
.val_bits = 8,
|
|
.max_register = LTC4222_ADC_CONTROL,
|
|
};
|
|
|
|
static int ltc4222_probe(struct i2c_client *client,
|
|
const struct i2c_device_id *id)
|
|
{
|
|
struct device *dev = &client->dev;
|
|
struct device *hwmon_dev;
|
|
struct regmap *regmap;
|
|
|
|
regmap = devm_regmap_init_i2c(client, <c4222_regmap_config);
|
|
if (IS_ERR(regmap)) {
|
|
dev_err(dev, "failed to allocate register map\n");
|
|
return PTR_ERR(regmap);
|
|
}
|
|
|
|
/* Clear faults */
|
|
regmap_write(regmap, LTC4222_FAULT1, 0x00);
|
|
regmap_write(regmap, LTC4222_FAULT2, 0x00);
|
|
|
|
hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
|
|
regmap,
|
|
ltc4222_groups);
|
|
return PTR_ERR_OR_ZERO(hwmon_dev);
|
|
}
|
|
|
|
static const struct i2c_device_id ltc4222_id[] = {
|
|
{"ltc4222", 0},
|
|
{ }
|
|
};
|
|
|
|
MODULE_DEVICE_TABLE(i2c, ltc4222_id);
|
|
|
|
static struct i2c_driver ltc4222_driver = {
|
|
.driver = {
|
|
.name = "ltc4222",
|
|
},
|
|
.probe = ltc4222_probe,
|
|
.id_table = ltc4222_id,
|
|
};
|
|
|
|
module_i2c_driver(ltc4222_driver);
|
|
|
|
MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
|
|
MODULE_DESCRIPTION("LTC4222 driver");
|
|
MODULE_LICENSE("GPL");
|