linux/drivers/hwmon/ltc4260.c
Thomas Gleixner c942fddf87 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157
Based on 3 normalized pattern(s):

  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

  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 [author] [kishon] [vijay] [abraham]
  [i] [kishon]@[ti] [com] 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

  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 [author] [graeme] [gregory]
  [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i]
  [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema]
  [hk] [hemahk]@[ti] [com] 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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1105 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:37 -07:00

186 lines
4.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Driver for Linear Technology LTC4260 I2C Positive Voltage Hot Swap Controller
*
* 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 LTC4260_CONTROL 0x00
#define LTC4260_ALERT 0x01
#define LTC4260_STATUS 0x02
#define LTC4260_FAULT 0x03
#define LTC4260_SENSE 0x04
#define LTC4260_SOURCE 0x05
#define LTC4260_ADIN 0x06
/*
* Fault register bits
*/
#define FAULT_OV (1 << 0)
#define FAULT_UV (1 << 1)
#define FAULT_OC (1 << 2)
#define FAULT_POWER_BAD (1 << 3)
#define FAULT_FET_SHORT (1 << 5)
/* Return the voltage from the given register in mV or mA */
static int ltc4260_get_value(struct device *dev, u8 reg)
{
struct regmap *regmap = dev_get_drvdata(dev);
unsigned int val;
int ret;
ret = regmap_read(regmap, reg, &val);
if (ret < 0)
return ret;
switch (reg) {
case LTC4260_ADIN:
/* 10 mV resolution. Convert to mV. */
val = val * 10;
break;
case LTC4260_SOURCE:
/* 400 mV resolution. Convert to mV. */
val = val * 400;
break;
case LTC4260_SENSE:
/*
* 300 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 = val * 300;
break;
default:
return -EINVAL;
}
return val;
}
static ssize_t ltc4260_value_show(struct device *dev,
struct device_attribute *da, char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
int value;
value = ltc4260_get_value(dev, attr->index);
if (value < 0)
return value;
return snprintf(buf, PAGE_SIZE, "%d\n", value);
}
static ssize_t ltc4260_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, LTC4260_FAULT, &fault);
if (ret < 0)
return ret;
fault &= attr->index;
if (fault) /* Clear reported faults in chip register */
regmap_update_bits(regmap, LTC4260_FAULT, attr->index, 0);
return snprintf(buf, PAGE_SIZE, "%d\n", !!fault);
}
/* Voltages */
static SENSOR_DEVICE_ATTR_RO(in1_input, ltc4260_value, LTC4260_SOURCE);
static SENSOR_DEVICE_ATTR_RO(in2_input, ltc4260_value, LTC4260_ADIN);
/*
* Voltage alarms
* UV/OV faults are associated with the input voltage, and the POWER BAD and
* FET SHORT faults are associated with the output voltage.
*/
static SENSOR_DEVICE_ATTR_RO(in1_min_alarm, ltc4260_bool, FAULT_UV);
static SENSOR_DEVICE_ATTR_RO(in1_max_alarm, ltc4260_bool, FAULT_OV);
static SENSOR_DEVICE_ATTR_RO(in2_alarm, ltc4260_bool,
FAULT_POWER_BAD | FAULT_FET_SHORT);
/* Current (via sense resistor) */
static SENSOR_DEVICE_ATTR_RO(curr1_input, ltc4260_value, LTC4260_SENSE);
/* Overcurrent alarm */
static SENSOR_DEVICE_ATTR_RO(curr1_max_alarm, ltc4260_bool, FAULT_OC);
static struct attribute *ltc4260_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_curr1_input.dev_attr.attr,
&sensor_dev_attr_curr1_max_alarm.dev_attr.attr,
NULL,
};
ATTRIBUTE_GROUPS(ltc4260);
static const struct regmap_config ltc4260_regmap_config = {
.reg_bits = 8,
.val_bits = 8,
.max_register = LTC4260_ADIN,
};
static int ltc4260_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, &ltc4260_regmap_config);
if (IS_ERR(regmap)) {
dev_err(dev, "failed to allocate register map\n");
return PTR_ERR(regmap);
}
/* Clear faults */
regmap_write(regmap, LTC4260_FAULT, 0x00);
hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
regmap,
ltc4260_groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
static const struct i2c_device_id ltc4260_id[] = {
{"ltc4260", 0},
{ }
};
MODULE_DEVICE_TABLE(i2c, ltc4260_id);
static struct i2c_driver ltc4260_driver = {
.driver = {
.name = "ltc4260",
},
.probe = ltc4260_probe,
.id_table = ltc4260_id,
};
module_i2c_driver(ltc4260_driver);
MODULE_AUTHOR("Guenter Roeck <linux@roeck-us.net>");
MODULE_DESCRIPTION("LTC4260 driver");
MODULE_LICENSE("GPL");