linux-stable/drivers/hwmon/ad7414.c
Stephen Kitt 6748703856 hwmon: use simple i2c probe function
Many hwmon drivers don't use the id information provided by the old
i2c probe function, and the remainder can easily be adapted to the new
form ("probe_new") by calling i2c_match_id explicitly.

This avoids scanning the identifier tables during probes.

Drivers which didn't use the id are converted as-is; drivers which did
are modified as follows:

* if the information in i2c_client is sufficient, that's used instead
  (client->name);
* anything else is handled by calling i2c_match_id() with the same
  level of error-handling (if any) as before.

A few drivers aren't included in this patch because they have a
different set of maintainers. They will be covered by other patches.

Signed-off-by: Stephen Kitt <steve@sk2.org>
Link: https://lore.kernel.org/r/20200813160222.1503401-1-steve@sk2.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2020-09-23 09:42:39 -07:00

234 lines
6.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* An hwmon driver for the Analog Devices AD7414
*
* Copyright 2006 Stefan Roese <sr at denx.de>, DENX Software Engineering
*
* Copyright (c) 2008 PIKA Technologies
* Sean MacLennan <smaclennan@pikatech.com>
*
* Copyright (c) 2008 Spansion Inc.
* Frank Edelhaeuser <frank.edelhaeuser at spansion.com>
* (converted to "new style" I2C driver model, removed checkpatch.pl warnings)
*
* Based on ad7418.c
* Copyright 2006 Tower Technologies, Alessandro Zummo <a.zummo at towertech.it>
*/
#include <linux/module.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/sysfs.h>
#include <linux/slab.h>
/* AD7414 registers */
#define AD7414_REG_TEMP 0x00
#define AD7414_REG_CONF 0x01
#define AD7414_REG_T_HIGH 0x02
#define AD7414_REG_T_LOW 0x03
static u8 AD7414_REG_LIMIT[] = { AD7414_REG_T_HIGH, AD7414_REG_T_LOW };
struct ad7414_data {
struct i2c_client *client;
struct mutex lock; /* atomic read data updates */
char valid; /* !=0 if following fields are valid */
unsigned long next_update; /* In jiffies */
s16 temp_input; /* Register values */
s8 temps[ARRAY_SIZE(AD7414_REG_LIMIT)];
};
/* REG: (0.25C/bit, two's complement) << 6 */
static inline int ad7414_temp_from_reg(s16 reg)
{
/*
* use integer division instead of equivalent right shift to
* guarantee arithmetic shift and preserve the sign
*/
return ((int)reg / 64) * 250;
}
static inline int ad7414_read(struct i2c_client *client, u8 reg)
{
if (reg == AD7414_REG_TEMP)
return i2c_smbus_read_word_swapped(client, reg);
else
return i2c_smbus_read_byte_data(client, reg);
}
static inline int ad7414_write(struct i2c_client *client, u8 reg, u8 value)
{
return i2c_smbus_write_byte_data(client, reg, value);
}
static struct ad7414_data *ad7414_update_device(struct device *dev)
{
struct ad7414_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
mutex_lock(&data->lock);
if (time_after(jiffies, data->next_update) || !data->valid) {
int value, i;
dev_dbg(&client->dev, "starting ad7414 update\n");
value = ad7414_read(client, AD7414_REG_TEMP);
if (value < 0)
dev_dbg(&client->dev, "AD7414_REG_TEMP err %d\n",
value);
else
data->temp_input = value;
for (i = 0; i < ARRAY_SIZE(AD7414_REG_LIMIT); ++i) {
value = ad7414_read(client, AD7414_REG_LIMIT[i]);
if (value < 0)
dev_dbg(&client->dev, "AD7414 reg %d err %d\n",
AD7414_REG_LIMIT[i], value);
else
data->temps[i] = value;
}
data->next_update = jiffies + HZ + HZ / 2;
data->valid = 1;
}
mutex_unlock(&data->lock);
return data;
}
static ssize_t temp_input_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct ad7414_data *data = ad7414_update_device(dev);
return sprintf(buf, "%d\n", ad7414_temp_from_reg(data->temp_input));
}
static SENSOR_DEVICE_ATTR_RO(temp1_input, temp_input, 0);
static ssize_t max_min_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
int index = to_sensor_dev_attr(attr)->index;
struct ad7414_data *data = ad7414_update_device(dev);
return sprintf(buf, "%d\n", data->temps[index] * 1000);
}
static ssize_t max_min_store(struct device *dev,
struct device_attribute *attr, const char *buf,
size_t count)
{
struct ad7414_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
int index = to_sensor_dev_attr(attr)->index;
u8 reg = AD7414_REG_LIMIT[index];
long temp;
int ret = kstrtol(buf, 10, &temp);
if (ret < 0)
return ret;
temp = clamp_val(temp, -40000, 85000);
temp = (temp + (temp < 0 ? -500 : 500)) / 1000;
mutex_lock(&data->lock);
data->temps[index] = temp;
ad7414_write(client, reg, temp);
mutex_unlock(&data->lock);
return count;
}
static SENSOR_DEVICE_ATTR_RW(temp1_max, max_min, 0);
static SENSOR_DEVICE_ATTR_RW(temp1_min, max_min, 1);
static ssize_t alarm_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
int bitnr = to_sensor_dev_attr(attr)->index;
struct ad7414_data *data = ad7414_update_device(dev);
int value = (data->temp_input >> bitnr) & 1;
return sprintf(buf, "%d\n", value);
}
static SENSOR_DEVICE_ATTR_RO(temp1_min_alarm, alarm, 3);
static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, alarm, 4);
static struct attribute *ad7414_attrs[] = {
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_temp1_max.dev_attr.attr,
&sensor_dev_attr_temp1_min.dev_attr.attr,
&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
NULL
};
ATTRIBUTE_GROUPS(ad7414);
static int ad7414_probe(struct i2c_client *client)
{
struct device *dev = &client->dev;
struct ad7414_data *data;
struct device *hwmon_dev;
int conf;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
I2C_FUNC_SMBUS_READ_WORD_DATA))
return -EOPNOTSUPP;
data = devm_kzalloc(dev, sizeof(struct ad7414_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->client = client;
mutex_init(&data->lock);
dev_info(&client->dev, "chip found\n");
/* Make sure the chip is powered up. */
conf = i2c_smbus_read_byte_data(client, AD7414_REG_CONF);
if (conf < 0)
dev_warn(dev, "ad7414_probe unable to read config register.\n");
else {
conf &= ~(1 << 7);
i2c_smbus_write_byte_data(client, AD7414_REG_CONF, conf);
}
hwmon_dev = devm_hwmon_device_register_with_groups(dev,
client->name,
data, ad7414_groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
static const struct i2c_device_id ad7414_id[] = {
{ "ad7414", 0 },
{}
};
MODULE_DEVICE_TABLE(i2c, ad7414_id);
static const struct of_device_id __maybe_unused ad7414_of_match[] = {
{ .compatible = "ad,ad7414" },
{ },
};
MODULE_DEVICE_TABLE(of, ad7414_of_match);
static struct i2c_driver ad7414_driver = {
.driver = {
.name = "ad7414",
.of_match_table = of_match_ptr(ad7414_of_match),
},
.probe_new = ad7414_probe,
.id_table = ad7414_id,
};
module_i2c_driver(ad7414_driver);
MODULE_AUTHOR("Stefan Roese <sr at denx.de>, "
"Frank Edelhaeuser <frank.edelhaeuser at spansion.com>");
MODULE_DESCRIPTION("AD7414 driver");
MODULE_LICENSE("GPL");