linux/drivers/hwmon/ad7418.c
Linus Walleij f4c2965e42 hwmon: (ad7418) Add device tree probing
This adds device tree probing for the AD7418 hwmon sensor.
When device tree is not enabled, stub functions will kick
in.

Tested on the Gateway Cambria GW2358-4.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
[groeck: Added missing {} to terminate ad7418_dt_ids]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2019-02-25 09:06:00 -08:00

321 lines
7.8 KiB
C

/*
* An hwmon driver for the Analog Devices AD7416/17/18
* Copyright (C) 2006-07 Tower Technologies
*
* Author: Alessandro Zummo <a.zummo@towertech.it>
*
* Based on lm75.c
* Copyright (C) 1998-99 Frodo Looijaard <frodol@dds.nl>
*
* 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 - version 2.
*/
#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/of_device.h>
#include <linux/delay.h>
#include <linux/slab.h>
#include "lm75.h"
#define DRV_VERSION "0.4"
enum chips { ad7416, ad7417, ad7418 };
/* AD7418 registers */
#define AD7418_REG_TEMP_IN 0x00
#define AD7418_REG_CONF 0x01
#define AD7418_REG_TEMP_HYST 0x02
#define AD7418_REG_TEMP_OS 0x03
#define AD7418_REG_ADC 0x04
#define AD7418_REG_CONF2 0x05
#define AD7418_REG_ADC_CH(x) ((x) << 5)
#define AD7418_CH_TEMP AD7418_REG_ADC_CH(0)
static const u8 AD7418_REG_TEMP[] = { AD7418_REG_TEMP_IN,
AD7418_REG_TEMP_HYST,
AD7418_REG_TEMP_OS };
struct ad7418_data {
struct i2c_client *client;
enum chips type;
struct mutex lock;
int adc_max; /* number of ADC channels */
char valid;
unsigned long last_updated; /* In jiffies */
s16 temp[3]; /* Register values */
u16 in[4];
};
static int ad7418_update_device(struct device *dev)
{
struct ad7418_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
s32 val;
mutex_lock(&data->lock);
if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
|| !data->valid) {
u8 cfg;
int i, ch;
/* read config register and clear channel bits */
val = i2c_smbus_read_byte_data(client, AD7418_REG_CONF);
if (val < 0)
goto abort;
cfg = val;
cfg &= 0x1F;
val = i2c_smbus_write_byte_data(client, AD7418_REG_CONF,
cfg | AD7418_CH_TEMP);
if (val < 0)
goto abort;
udelay(30);
for (i = 0; i < 3; i++) {
val = i2c_smbus_read_word_swapped(client,
AD7418_REG_TEMP[i]);
if (val < 0)
goto abort;
data->temp[i] = val;
}
for (i = 0, ch = 4; i < data->adc_max; i++, ch--) {
val = i2c_smbus_write_byte_data(client, AD7418_REG_CONF,
cfg | AD7418_REG_ADC_CH(ch));
if (val < 0)
goto abort;
udelay(15);
val = i2c_smbus_read_word_swapped(client,
AD7418_REG_ADC);
if (val < 0)
goto abort;
data->in[data->adc_max - 1 - i] = val;
}
/* restore old configuration value */
val = i2c_smbus_write_word_swapped(client, AD7418_REG_CONF,
cfg);
if (val < 0)
goto abort;
data->last_updated = jiffies;
data->valid = 1;
}
mutex_unlock(&data->lock);
return 0;
abort:
data->valid = 0;
mutex_unlock(&data->lock);
return val;
}
static ssize_t temp_show(struct device *dev, struct device_attribute *devattr,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct ad7418_data *data = dev_get_drvdata(dev);
int ret;
ret = ad7418_update_device(dev);
if (ret < 0)
return ret;
return sprintf(buf, "%d\n",
LM75_TEMP_FROM_REG(data->temp[attr->index]));
}
static ssize_t adc_show(struct device *dev, struct device_attribute *devattr,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct ad7418_data *data = dev_get_drvdata(dev);
int ret;
ret = ad7418_update_device(dev);
if (ret < 0)
return ret;
return sprintf(buf, "%d\n",
((data->in[attr->index] >> 6) * 2500 + 512) / 1024);
}
static ssize_t temp_store(struct device *dev,
struct device_attribute *devattr, const char *buf,
size_t count)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(devattr);
struct ad7418_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
long temp;
int ret = kstrtol(buf, 10, &temp);
if (ret < 0)
return ret;
mutex_lock(&data->lock);
data->temp[attr->index] = LM75_TEMP_TO_REG(temp);
i2c_smbus_write_word_swapped(client,
AD7418_REG_TEMP[attr->index],
data->temp[attr->index]);
mutex_unlock(&data->lock);
return count;
}
static SENSOR_DEVICE_ATTR_RO(temp1_input, temp, 0);
static SENSOR_DEVICE_ATTR_RW(temp1_max_hyst, temp, 1);
static SENSOR_DEVICE_ATTR_RW(temp1_max, temp, 2);
static SENSOR_DEVICE_ATTR_RO(in1_input, adc, 0);
static SENSOR_DEVICE_ATTR_RO(in2_input, adc, 1);
static SENSOR_DEVICE_ATTR_RO(in3_input, adc, 2);
static SENSOR_DEVICE_ATTR_RO(in4_input, adc, 3);
static struct attribute *ad7416_attrs[] = {
&sensor_dev_attr_temp1_max.dev_attr.attr,
&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
&sensor_dev_attr_temp1_input.dev_attr.attr,
NULL
};
ATTRIBUTE_GROUPS(ad7416);
static struct attribute *ad7417_attrs[] = {
&sensor_dev_attr_temp1_max.dev_attr.attr,
&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_in1_input.dev_attr.attr,
&sensor_dev_attr_in2_input.dev_attr.attr,
&sensor_dev_attr_in3_input.dev_attr.attr,
&sensor_dev_attr_in4_input.dev_attr.attr,
NULL
};
ATTRIBUTE_GROUPS(ad7417);
static struct attribute *ad7418_attrs[] = {
&sensor_dev_attr_temp1_max.dev_attr.attr,
&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_in1_input.dev_attr.attr,
NULL
};
ATTRIBUTE_GROUPS(ad7418);
static void ad7418_init_client(struct i2c_client *client)
{
struct ad7418_data *data = i2c_get_clientdata(client);
int reg = i2c_smbus_read_byte_data(client, AD7418_REG_CONF);
if (reg < 0) {
dev_err(&client->dev, "cannot read configuration register\n");
} else {
dev_info(&client->dev, "configuring for mode 1\n");
i2c_smbus_write_byte_data(client, AD7418_REG_CONF, reg & 0xfe);
if (data->type == ad7417 || data->type == ad7418)
i2c_smbus_write_byte_data(client,
AD7418_REG_CONF2, 0x00);
}
}
static int ad7418_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct device *dev = &client->dev;
struct i2c_adapter *adapter = client->adapter;
struct ad7418_data *data;
struct device *hwmon_dev;
const struct attribute_group **attr_groups = NULL;
if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA |
I2C_FUNC_SMBUS_WORD_DATA))
return -EOPNOTSUPP;
data = devm_kzalloc(dev, sizeof(struct ad7418_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
i2c_set_clientdata(client, data);
mutex_init(&data->lock);
data->client = client;
if (dev->of_node)
data->type = (enum chips)of_device_get_match_data(dev);
else
data->type = id->driver_data;
switch (data->type) {
case ad7416:
data->adc_max = 0;
attr_groups = ad7416_groups;
break;
case ad7417:
data->adc_max = 4;
attr_groups = ad7417_groups;
break;
case ad7418:
data->adc_max = 1;
attr_groups = ad7418_groups;
break;
}
dev_info(dev, "%s chip found\n", client->name);
/* Initialize the AD7418 chip */
ad7418_init_client(client);
hwmon_dev = devm_hwmon_device_register_with_groups(dev,
client->name,
data, attr_groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
static const struct i2c_device_id ad7418_id[] = {
{ "ad7416", ad7416 },
{ "ad7417", ad7417 },
{ "ad7418", ad7418 },
{ }
};
MODULE_DEVICE_TABLE(i2c, ad7418_id);
static const struct of_device_id ad7418_dt_ids[] = {
{ .compatible = "adi,ad7416", .data = (void *)ad7416, },
{ .compatible = "adi,ad7417", .data = (void *)ad7417, },
{ .compatible = "adi,ad7418", .data = (void *)ad7418, },
{ }
};
MODULE_DEVICE_TABLE(of, ad7418_dt_ids);
static struct i2c_driver ad7418_driver = {
.driver = {
.name = "ad7418",
.of_match_table = ad7418_dt_ids,
},
.probe = ad7418_probe,
.id_table = ad7418_id,
};
module_i2c_driver(ad7418_driver);
MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
MODULE_DESCRIPTION("AD7416/17/18 driver");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);