linux/drivers/hwmon/adc128d818.c
Guenter Roeck 462d7e7ec9 hwmon: (adc128d818) Fix build warning
If CONFIG_OF is not enabled, the following build warning is observed.

drivers/hwmon/adc128d818.c:524:34: warning:
	‘adc128_of_match’ defined but not used

Mark adc128_of_match as __maybe_unused to fix the problem.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2019-04-15 17:19:53 -07:00

548 lines
15 KiB
C

/*
* Driver for TI ADC128D818 System Monitor with Temperature Sensor
*
* Copyright (c) 2014 Guenter Roeck
*
* Derived from lm80.c
* Copyright (C) 1998, 1999 Frodo Looijaard <frodol@dds.nl>
* and Philip Edelbrock <phil@netroedge.com>
*
* 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/module.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/regulator/consumer.h>
#include <linux/mutex.h>
#include <linux/bitops.h>
#include <linux/of.h>
/* Addresses to scan
* The chip also supports addresses 0x35..0x37. Don't scan those addresses
* since they are also used by some EEPROMs, which may result in false
* positives.
*/
static const unsigned short normal_i2c[] = {
0x1d, 0x1e, 0x1f, 0x2d, 0x2e, 0x2f, I2C_CLIENT_END };
/* registers */
#define ADC128_REG_IN_MAX(nr) (0x2a + (nr) * 2)
#define ADC128_REG_IN_MIN(nr) (0x2b + (nr) * 2)
#define ADC128_REG_IN(nr) (0x20 + (nr))
#define ADC128_REG_TEMP 0x27
#define ADC128_REG_TEMP_MAX 0x38
#define ADC128_REG_TEMP_HYST 0x39
#define ADC128_REG_CONFIG 0x00
#define ADC128_REG_ALARM 0x01
#define ADC128_REG_MASK 0x03
#define ADC128_REG_CONV_RATE 0x07
#define ADC128_REG_ONESHOT 0x09
#define ADC128_REG_SHUTDOWN 0x0a
#define ADC128_REG_CONFIG_ADV 0x0b
#define ADC128_REG_BUSY_STATUS 0x0c
#define ADC128_REG_MAN_ID 0x3e
#define ADC128_REG_DEV_ID 0x3f
/* No. of voltage entries in adc128_attrs */
#define ADC128_ATTR_NUM_VOLT (8 * 4)
/* Voltage inputs visible per operation mode */
static const u8 num_inputs[] = { 7, 8, 4, 6 };
struct adc128_data {
struct i2c_client *client;
struct regulator *regulator;
int vref; /* Reference voltage in mV */
struct mutex update_lock;
u8 mode; /* Operation mode */
bool valid; /* true if following fields are valid */
unsigned long last_updated; /* In jiffies */
u16 in[3][8]; /* Register value, normalized to 12 bit
* 0: input voltage
* 1: min limit
* 2: max limit
*/
s16 temp[3]; /* Register value, normalized to 9 bit
* 0: sensor 1: limit 2: hyst
*/
u8 alarms; /* alarm register value */
};
static struct adc128_data *adc128_update_device(struct device *dev)
{
struct adc128_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
struct adc128_data *ret = data;
int i, rv;
mutex_lock(&data->update_lock);
if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
for (i = 0; i < num_inputs[data->mode]; i++) {
rv = i2c_smbus_read_word_swapped(client,
ADC128_REG_IN(i));
if (rv < 0)
goto abort;
data->in[0][i] = rv >> 4;
rv = i2c_smbus_read_byte_data(client,
ADC128_REG_IN_MIN(i));
if (rv < 0)
goto abort;
data->in[1][i] = rv << 4;
rv = i2c_smbus_read_byte_data(client,
ADC128_REG_IN_MAX(i));
if (rv < 0)
goto abort;
data->in[2][i] = rv << 4;
}
if (data->mode != 1) {
rv = i2c_smbus_read_word_swapped(client,
ADC128_REG_TEMP);
if (rv < 0)
goto abort;
data->temp[0] = rv >> 7;
rv = i2c_smbus_read_byte_data(client,
ADC128_REG_TEMP_MAX);
if (rv < 0)
goto abort;
data->temp[1] = rv << 1;
rv = i2c_smbus_read_byte_data(client,
ADC128_REG_TEMP_HYST);
if (rv < 0)
goto abort;
data->temp[2] = rv << 1;
}
rv = i2c_smbus_read_byte_data(client, ADC128_REG_ALARM);
if (rv < 0)
goto abort;
data->alarms |= rv;
data->last_updated = jiffies;
data->valid = true;
}
goto done;
abort:
ret = ERR_PTR(rv);
data->valid = false;
done:
mutex_unlock(&data->update_lock);
return ret;
}
static ssize_t adc128_in_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct adc128_data *data = adc128_update_device(dev);
int index = to_sensor_dev_attr_2(attr)->index;
int nr = to_sensor_dev_attr_2(attr)->nr;
int val;
if (IS_ERR(data))
return PTR_ERR(data);
val = DIV_ROUND_CLOSEST(data->in[index][nr] * data->vref, 4095);
return sprintf(buf, "%d\n", val);
}
static ssize_t adc128_in_store(struct device *dev,
struct device_attribute *attr, const char *buf,
size_t count)
{
struct adc128_data *data = dev_get_drvdata(dev);
int index = to_sensor_dev_attr_2(attr)->index;
int nr = to_sensor_dev_attr_2(attr)->nr;
u8 reg, regval;
long val;
int err;
err = kstrtol(buf, 10, &val);
if (err < 0)
return err;
mutex_lock(&data->update_lock);
/* 10 mV LSB on limit registers */
regval = clamp_val(DIV_ROUND_CLOSEST(val, 10), 0, 255);
data->in[index][nr] = regval << 4;
reg = index == 1 ? ADC128_REG_IN_MIN(nr) : ADC128_REG_IN_MAX(nr);
i2c_smbus_write_byte_data(data->client, reg, regval);
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t adc128_temp_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct adc128_data *data = adc128_update_device(dev);
int index = to_sensor_dev_attr(attr)->index;
int temp;
if (IS_ERR(data))
return PTR_ERR(data);
temp = sign_extend32(data->temp[index], 8);
return sprintf(buf, "%d\n", temp * 500);/* 0.5 degrees C resolution */
}
static ssize_t adc128_temp_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct adc128_data *data = dev_get_drvdata(dev);
int index = to_sensor_dev_attr(attr)->index;
long val;
int err;
s8 regval;
err = kstrtol(buf, 10, &val);
if (err < 0)
return err;
mutex_lock(&data->update_lock);
regval = clamp_val(DIV_ROUND_CLOSEST(val, 1000), -128, 127);
data->temp[index] = regval << 1;
i2c_smbus_write_byte_data(data->client,
index == 1 ? ADC128_REG_TEMP_MAX
: ADC128_REG_TEMP_HYST,
regval);
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t adc128_alarm_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct adc128_data *data = adc128_update_device(dev);
int mask = 1 << to_sensor_dev_attr(attr)->index;
u8 alarms;
if (IS_ERR(data))
return PTR_ERR(data);
/*
* Clear an alarm after reporting it to user space. If it is still
* active, the next update sequence will set the alarm bit again.
*/
alarms = data->alarms;
data->alarms &= ~mask;
return sprintf(buf, "%u\n", !!(alarms & mask));
}
static umode_t adc128_is_visible(struct kobject *kobj,
struct attribute *attr, int index)
{
struct device *dev = container_of(kobj, struct device, kobj);
struct adc128_data *data = dev_get_drvdata(dev);
if (index < ADC128_ATTR_NUM_VOLT) {
/* Voltage, visible according to num_inputs[] */
if (index >= num_inputs[data->mode] * 4)
return 0;
} else {
/* Temperature, visible if not in mode 1 */
if (data->mode == 1)
return 0;
}
return attr->mode;
}
static SENSOR_DEVICE_ATTR_2_RO(in0_input, adc128_in, 0, 0);
static SENSOR_DEVICE_ATTR_2_RW(in0_min, adc128_in, 0, 1);
static SENSOR_DEVICE_ATTR_2_RW(in0_max, adc128_in, 0, 2);
static SENSOR_DEVICE_ATTR_2_RO(in1_input, adc128_in, 1, 0);
static SENSOR_DEVICE_ATTR_2_RW(in1_min, adc128_in, 1, 1);
static SENSOR_DEVICE_ATTR_2_RW(in1_max, adc128_in, 1, 2);
static SENSOR_DEVICE_ATTR_2_RO(in2_input, adc128_in, 2, 0);
static SENSOR_DEVICE_ATTR_2_RW(in2_min, adc128_in, 2, 1);
static SENSOR_DEVICE_ATTR_2_RW(in2_max, adc128_in, 2, 2);
static SENSOR_DEVICE_ATTR_2_RO(in3_input, adc128_in, 3, 0);
static SENSOR_DEVICE_ATTR_2_RW(in3_min, adc128_in, 3, 1);
static SENSOR_DEVICE_ATTR_2_RW(in3_max, adc128_in, 3, 2);
static SENSOR_DEVICE_ATTR_2_RO(in4_input, adc128_in, 4, 0);
static SENSOR_DEVICE_ATTR_2_RW(in4_min, adc128_in, 4, 1);
static SENSOR_DEVICE_ATTR_2_RW(in4_max, adc128_in, 4, 2);
static SENSOR_DEVICE_ATTR_2_RO(in5_input, adc128_in, 5, 0);
static SENSOR_DEVICE_ATTR_2_RW(in5_min, adc128_in, 5, 1);
static SENSOR_DEVICE_ATTR_2_RW(in5_max, adc128_in, 5, 2);
static SENSOR_DEVICE_ATTR_2_RO(in6_input, adc128_in, 6, 0);
static SENSOR_DEVICE_ATTR_2_RW(in6_min, adc128_in, 6, 1);
static SENSOR_DEVICE_ATTR_2_RW(in6_max, adc128_in, 6, 2);
static SENSOR_DEVICE_ATTR_2_RO(in7_input, adc128_in, 7, 0);
static SENSOR_DEVICE_ATTR_2_RW(in7_min, adc128_in, 7, 1);
static SENSOR_DEVICE_ATTR_2_RW(in7_max, adc128_in, 7, 2);
static SENSOR_DEVICE_ATTR_RO(temp1_input, adc128_temp, 0);
static SENSOR_DEVICE_ATTR_RW(temp1_max, adc128_temp, 1);
static SENSOR_DEVICE_ATTR_RW(temp1_max_hyst, adc128_temp, 2);
static SENSOR_DEVICE_ATTR_RO(in0_alarm, adc128_alarm, 0);
static SENSOR_DEVICE_ATTR_RO(in1_alarm, adc128_alarm, 1);
static SENSOR_DEVICE_ATTR_RO(in2_alarm, adc128_alarm, 2);
static SENSOR_DEVICE_ATTR_RO(in3_alarm, adc128_alarm, 3);
static SENSOR_DEVICE_ATTR_RO(in4_alarm, adc128_alarm, 4);
static SENSOR_DEVICE_ATTR_RO(in5_alarm, adc128_alarm, 5);
static SENSOR_DEVICE_ATTR_RO(in6_alarm, adc128_alarm, 6);
static SENSOR_DEVICE_ATTR_RO(in7_alarm, adc128_alarm, 7);
static SENSOR_DEVICE_ATTR_RO(temp1_max_alarm, adc128_alarm, 7);
static struct attribute *adc128_attrs[] = {
&sensor_dev_attr_in0_alarm.dev_attr.attr,
&sensor_dev_attr_in0_input.dev_attr.attr,
&sensor_dev_attr_in0_max.dev_attr.attr,
&sensor_dev_attr_in0_min.dev_attr.attr,
&sensor_dev_attr_in1_alarm.dev_attr.attr,
&sensor_dev_attr_in1_input.dev_attr.attr,
&sensor_dev_attr_in1_max.dev_attr.attr,
&sensor_dev_attr_in1_min.dev_attr.attr,
&sensor_dev_attr_in2_alarm.dev_attr.attr,
&sensor_dev_attr_in2_input.dev_attr.attr,
&sensor_dev_attr_in2_max.dev_attr.attr,
&sensor_dev_attr_in2_min.dev_attr.attr,
&sensor_dev_attr_in3_alarm.dev_attr.attr,
&sensor_dev_attr_in3_input.dev_attr.attr,
&sensor_dev_attr_in3_max.dev_attr.attr,
&sensor_dev_attr_in3_min.dev_attr.attr,
&sensor_dev_attr_in4_alarm.dev_attr.attr,
&sensor_dev_attr_in4_input.dev_attr.attr,
&sensor_dev_attr_in4_max.dev_attr.attr,
&sensor_dev_attr_in4_min.dev_attr.attr,
&sensor_dev_attr_in5_alarm.dev_attr.attr,
&sensor_dev_attr_in5_input.dev_attr.attr,
&sensor_dev_attr_in5_max.dev_attr.attr,
&sensor_dev_attr_in5_min.dev_attr.attr,
&sensor_dev_attr_in6_alarm.dev_attr.attr,
&sensor_dev_attr_in6_input.dev_attr.attr,
&sensor_dev_attr_in6_max.dev_attr.attr,
&sensor_dev_attr_in6_min.dev_attr.attr,
&sensor_dev_attr_in7_alarm.dev_attr.attr,
&sensor_dev_attr_in7_input.dev_attr.attr,
&sensor_dev_attr_in7_max.dev_attr.attr,
&sensor_dev_attr_in7_min.dev_attr.attr,
&sensor_dev_attr_temp1_input.dev_attr.attr,
&sensor_dev_attr_temp1_max.dev_attr.attr,
&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
NULL
};
static const struct attribute_group adc128_group = {
.attrs = adc128_attrs,
.is_visible = adc128_is_visible,
};
__ATTRIBUTE_GROUPS(adc128);
static int adc128_detect(struct i2c_client *client, struct i2c_board_info *info)
{
int man_id, dev_id;
if (!i2c_check_functionality(client->adapter,
I2C_FUNC_SMBUS_BYTE_DATA |
I2C_FUNC_SMBUS_WORD_DATA))
return -ENODEV;
man_id = i2c_smbus_read_byte_data(client, ADC128_REG_MAN_ID);
dev_id = i2c_smbus_read_byte_data(client, ADC128_REG_DEV_ID);
if (man_id != 0x01 || dev_id != 0x09)
return -ENODEV;
/* Check unused bits for confirmation */
if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG) & 0xf4)
return -ENODEV;
if (i2c_smbus_read_byte_data(client, ADC128_REG_CONV_RATE) & 0xfe)
return -ENODEV;
if (i2c_smbus_read_byte_data(client, ADC128_REG_ONESHOT) & 0xfe)
return -ENODEV;
if (i2c_smbus_read_byte_data(client, ADC128_REG_SHUTDOWN) & 0xfe)
return -ENODEV;
if (i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV) & 0xf8)
return -ENODEV;
if (i2c_smbus_read_byte_data(client, ADC128_REG_BUSY_STATUS) & 0xfc)
return -ENODEV;
strlcpy(info->type, "adc128d818", I2C_NAME_SIZE);
return 0;
}
static int adc128_init_client(struct adc128_data *data)
{
struct i2c_client *client = data->client;
int err;
/*
* Reset chip to defaults.
* This makes most other initializations unnecessary.
*/
err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x80);
if (err)
return err;
/* Set operation mode, if non-default */
if (data->mode != 0) {
err = i2c_smbus_write_byte_data(client,
ADC128_REG_CONFIG_ADV,
data->mode << 1);
if (err)
return err;
}
/* Start monitoring */
err = i2c_smbus_write_byte_data(client, ADC128_REG_CONFIG, 0x01);
if (err)
return err;
/* If external vref is selected, configure the chip to use it */
if (data->regulator) {
err = i2c_smbus_write_byte_data(client,
ADC128_REG_CONFIG_ADV, 0x01);
if (err)
return err;
}
return 0;
}
static int adc128_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct device *dev = &client->dev;
struct regulator *regulator;
struct device *hwmon_dev;
struct adc128_data *data;
int err, vref;
data = devm_kzalloc(dev, sizeof(struct adc128_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
/* vref is optional. If specified, is used as chip reference voltage */
regulator = devm_regulator_get_optional(dev, "vref");
if (!IS_ERR(regulator)) {
data->regulator = regulator;
err = regulator_enable(regulator);
if (err < 0)
return err;
vref = regulator_get_voltage(regulator);
if (vref < 0) {
err = vref;
goto error;
}
data->vref = DIV_ROUND_CLOSEST(vref, 1000);
} else {
data->vref = 2560; /* 2.56V, in mV */
}
/* Operation mode is optional. If unspecified, keep current mode */
if (of_property_read_u8(dev->of_node, "ti,mode", &data->mode) == 0) {
if (data->mode > 3) {
dev_err(dev, "invalid operation mode %d\n",
data->mode);
err = -EINVAL;
goto error;
}
} else {
err = i2c_smbus_read_byte_data(client, ADC128_REG_CONFIG_ADV);
if (err < 0)
goto error;
data->mode = (err >> 1) & ADC128_REG_MASK;
}
data->client = client;
i2c_set_clientdata(client, data);
mutex_init(&data->update_lock);
/* Initialize the chip */
err = adc128_init_client(data);
if (err < 0)
goto error;
hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name,
data, adc128_groups);
if (IS_ERR(hwmon_dev)) {
err = PTR_ERR(hwmon_dev);
goto error;
}
return 0;
error:
if (data->regulator)
regulator_disable(data->regulator);
return err;
}
static int adc128_remove(struct i2c_client *client)
{
struct adc128_data *data = i2c_get_clientdata(client);
if (data->regulator)
regulator_disable(data->regulator);
return 0;
}
static const struct i2c_device_id adc128_id[] = {
{ "adc128d818", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, adc128_id);
static const struct of_device_id __maybe_unused adc128_of_match[] = {
{ .compatible = "ti,adc128d818" },
{ },
};
MODULE_DEVICE_TABLE(of, adc128_of_match);
static struct i2c_driver adc128_driver = {
.class = I2C_CLASS_HWMON,
.driver = {
.name = "adc128d818",
.of_match_table = of_match_ptr(adc128_of_match),
},
.probe = adc128_probe,
.remove = adc128_remove,
.id_table = adc128_id,
.detect = adc128_detect,
.address_list = normal_i2c,
};
module_i2c_driver(adc128_driver);
MODULE_AUTHOR("Guenter Roeck");
MODULE_DESCRIPTION("Driver for ADC128D818");
MODULE_LICENSE("GPL");