blob: bdeaece9641d4ace87a2bd5a21917fc35adeb3bd [file] [log] [blame]
/*
* Driver for the ADT7411 (I2C/SPI 8 channel 10 bit ADC & temperature-sensor)
*
* Copyright (C) 2008, 2010 Pengutronix
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* TODO: SPI, use power-down mode for suspend?, interrupt handling?
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/jiffies.h>
#include <linux/i2c.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/slab.h>
#define ADT7411_REG_INT_TEMP_VDD_LSB 0x03
#define ADT7411_REG_EXT_TEMP_AIN14_LSB 0x04
#define ADT7411_REG_VDD_MSB 0x06
#define ADT7411_REG_INT_TEMP_MSB 0x07
#define ADT7411_REG_EXT_TEMP_AIN1_MSB 0x08
#define ADT7411_REG_CFG1 0x18
#define ADT7411_CFG1_START_MONITOR (1 << 0)
#define ADT7411_CFG1_RESERVED_BIT1 (1 << 1)
#define ADT7411_CFG1_EXT_TDM (1 << 2)
#define ADT7411_CFG1_RESERVED_BIT3 (1 << 3)
#define ADT7411_REG_CFG2 0x19
#define ADT7411_CFG2_DISABLE_AVG (1 << 5)
#define ADT7411_REG_CFG3 0x1a
#define ADT7411_CFG3_ADC_CLK_225 (1 << 0)
#define ADT7411_CFG3_RESERVED_BIT1 (1 << 1)
#define ADT7411_CFG3_RESERVED_BIT2 (1 << 2)
#define ADT7411_CFG3_RESERVED_BIT3 (1 << 3)
#define ADT7411_CFG3_REF_VDD (1 << 4)
#define ADT7411_REG_DEVICE_ID 0x4d
#define ADT7411_REG_MANUFACTURER_ID 0x4e
#define ADT7411_DEVICE_ID 0x2
#define ADT7411_MANUFACTURER_ID 0x41
static const unsigned short normal_i2c[] = { 0x48, 0x4a, 0x4b, I2C_CLIENT_END };
struct adt7411_data {
struct mutex device_lock; /* for "atomic" device accesses */
struct mutex update_lock;
unsigned long next_update;
long vref_cached;
struct i2c_client *client;
bool use_ext_temp;
};
/*
* When reading a register containing (up to 4) lsb, all associated
* msb-registers get locked by the hardware. After _one_ of those msb is read,
* _all_ are unlocked. In order to use this locking correctly, reading lsb/msb
* is protected here with a mutex, too.
*/
static int adt7411_read_10_bit(struct i2c_client *client, u8 lsb_reg,
u8 msb_reg, u8 lsb_shift)
{
struct adt7411_data *data = i2c_get_clientdata(client);
int val, tmp;
mutex_lock(&data->device_lock);
val = i2c_smbus_read_byte_data(client, lsb_reg);
if (val < 0)
goto exit_unlock;
tmp = (val >> lsb_shift) & 3;
val = i2c_smbus_read_byte_data(client, msb_reg);
if (val >= 0)
val = (val << 2) | tmp;
exit_unlock:
mutex_unlock(&data->device_lock);
return val;
}
static int adt7411_modify_bit(struct i2c_client *client, u8 reg, u8 bit,
bool flag)
{
struct adt7411_data *data = i2c_get_clientdata(client);
int ret, val;
mutex_lock(&data->device_lock);
ret = i2c_smbus_read_byte_data(client, reg);
if (ret < 0)
goto exit_unlock;
if (flag)
val = ret | bit;
else
val = ret & ~bit;
ret = i2c_smbus_write_byte_data(client, reg, val);
exit_unlock:
mutex_unlock(&data->device_lock);
return ret;
}
static ssize_t adt7411_show_bit(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct sensor_device_attribute_2 *attr2 = to_sensor_dev_attr_2(attr);
struct adt7411_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
int ret = i2c_smbus_read_byte_data(client, attr2->index);
return ret < 0 ? ret : sprintf(buf, "%u\n", !!(ret & attr2->nr));
}
static ssize_t adt7411_set_bit(struct device *dev,
struct device_attribute *attr, const char *buf,
size_t count)
{
struct sensor_device_attribute_2 *s_attr2 = to_sensor_dev_attr_2(attr);
struct adt7411_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
int ret;
unsigned long flag;
ret = kstrtoul(buf, 0, &flag);
if (ret || flag > 1)
return -EINVAL;
ret = adt7411_modify_bit(client, s_attr2->index, s_attr2->nr, flag);
/* force update */
mutex_lock(&data->update_lock);
data->next_update = jiffies;
mutex_unlock(&data->update_lock);
return ret < 0 ? ret : count;
}
#define ADT7411_BIT_ATTR(__name, __reg, __bit) \
SENSOR_DEVICE_ATTR_2(__name, S_IRUGO | S_IWUSR, adt7411_show_bit, \
adt7411_set_bit, __bit, __reg)
static ADT7411_BIT_ATTR(no_average, ADT7411_REG_CFG2, ADT7411_CFG2_DISABLE_AVG);
static ADT7411_BIT_ATTR(fast_sampling, ADT7411_REG_CFG3, ADT7411_CFG3_ADC_CLK_225);
static ADT7411_BIT_ATTR(adc_ref_vdd, ADT7411_REG_CFG3, ADT7411_CFG3_REF_VDD);
static struct attribute *adt7411_attrs[] = {
&sensor_dev_attr_no_average.dev_attr.attr,
&sensor_dev_attr_fast_sampling.dev_attr.attr,
&sensor_dev_attr_adc_ref_vdd.dev_attr.attr,
NULL
};
ATTRIBUTE_GROUPS(adt7411);
static int adt7411_read_in_vdd(struct device *dev, u32 attr, long *val)
{
struct adt7411_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
int ret;
switch (attr) {
case hwmon_in_input:
ret = adt7411_read_10_bit(client, ADT7411_REG_INT_TEMP_VDD_LSB,
ADT7411_REG_VDD_MSB, 2);
if (ret < 0)
return ret;
*val = ret * 7000 / 1024;
return 0;
default:
return -EOPNOTSUPP;
}
}
static int adt7411_read_in_chan(struct device *dev, u32 attr, int channel,
long *val)
{
struct adt7411_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
int ret;
int lsb_reg, lsb_shift;
int nr = channel - 1;
mutex_lock(&data->update_lock);
if (time_after_eq(jiffies, data->next_update)) {
ret = i2c_smbus_read_byte_data(client, ADT7411_REG_CFG3);
if (ret < 0)
goto exit_unlock;
if (ret & ADT7411_CFG3_REF_VDD) {
ret = adt7411_read_in_vdd(dev, hwmon_in_input,
&data->vref_cached);
if (ret < 0)
goto exit_unlock;
} else {
data->vref_cached = 2250;
}
data->next_update = jiffies + HZ;
}
switch (attr) {
case hwmon_in_input:
lsb_reg = ADT7411_REG_EXT_TEMP_AIN14_LSB + (nr >> 2);
lsb_shift = 2 * (nr & 0x03);
ret = adt7411_read_10_bit(client, lsb_reg,
ADT7411_REG_EXT_TEMP_AIN1_MSB + nr,
lsb_shift);
if (ret < 0)
goto exit_unlock;
*val = ret * data->vref_cached / 1024;
ret = 0;
break;
default:
ret = -EOPNOTSUPP;
break;
}
exit_unlock:
mutex_unlock(&data->update_lock);
return ret;
}
static int adt7411_read_in(struct device *dev, u32 attr, int channel,
long *val)
{
if (channel == 0)
return adt7411_read_in_vdd(dev, attr, val);
else
return adt7411_read_in_chan(dev, attr, channel, val);
}
static int adt7411_read_temp(struct device *dev, u32 attr, int channel,
long *val)
{
struct adt7411_data *data = dev_get_drvdata(dev);
struct i2c_client *client = data->client;
int ret, regl, regh;
switch (attr) {
case hwmon_temp_input:
regl = channel ? ADT7411_REG_EXT_TEMP_AIN14_LSB :
ADT7411_REG_INT_TEMP_VDD_LSB;
regh = channel ? ADT7411_REG_EXT_TEMP_AIN1_MSB :
ADT7411_REG_INT_TEMP_MSB;
ret = adt7411_read_10_bit(client, regl, regh, 0);
if (ret < 0)
return ret;
ret = ret & 0x200 ? ret - 0x400 : ret; /* 10 bit signed */
*val = ret * 250;
return 0;
default:
return -EOPNOTSUPP;
}
}
static int adt7411_read(struct device *dev, enum hwmon_sensor_types type,
u32 attr, int channel, long *val)
{
switch (type) {
case hwmon_in:
return adt7411_read_in(dev, attr, channel, val);
case hwmon_temp:
return adt7411_read_temp(dev, attr, channel, val);
default:
return -EOPNOTSUPP;
}
}
static umode_t adt7411_is_visible(const void *_data,
enum hwmon_sensor_types type,
u32 attr, int channel)
{
const struct adt7411_data *data = _data;
switch (type) {
case hwmon_in:
if (channel > 0 && channel < 3)
return data->use_ext_temp ? 0 : S_IRUGO;
else
return S_IRUGO;
case hwmon_temp:
if (channel == 1)
return data->use_ext_temp ? S_IRUGO : 0;
else
return S_IRUGO;
default:
return 0;
}
}
static int adt7411_detect(struct i2c_client *client,
struct i2c_board_info *info)
{
int val;
if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA))
return -ENODEV;
val = i2c_smbus_read_byte_data(client, ADT7411_REG_MANUFACTURER_ID);
if (val < 0 || val != ADT7411_MANUFACTURER_ID) {
dev_dbg(&client->dev,
"Wrong manufacturer ID. Got %d, expected %d\n",
val, ADT7411_MANUFACTURER_ID);
return -ENODEV;
}
val = i2c_smbus_read_byte_data(client, ADT7411_REG_DEVICE_ID);
if (val < 0 || val != ADT7411_DEVICE_ID) {
dev_dbg(&client->dev,
"Wrong device ID. Got %d, expected %d\n",
val, ADT7411_DEVICE_ID);
return -ENODEV;
}
strlcpy(info->type, "adt7411", I2C_NAME_SIZE);
return 0;
}
static int adt7411_init_device(struct adt7411_data *data)
{
int ret;
u8 val;
ret = i2c_smbus_read_byte_data(data->client, ADT7411_REG_CFG3);
if (ret < 0)
return ret;
/*
* We must only write zero to bit 1 and bit 2 and only one to bit 3
* according to the datasheet.
*/
val = ret;
val &= ~(ADT7411_CFG3_RESERVED_BIT1 | ADT7411_CFG3_RESERVED_BIT2);
val |= ADT7411_CFG3_RESERVED_BIT3;
ret = i2c_smbus_write_byte_data(data->client, ADT7411_REG_CFG3, val);
if (ret < 0)
return ret;
ret = i2c_smbus_read_byte_data(data->client, ADT7411_REG_CFG1);
if (ret < 0)
return ret;
data->use_ext_temp = ret & ADT7411_CFG1_EXT_TDM;
/*
* We must only write zero to bit 1 and only one to bit 3 according to
* the datasheet.
*/
val = ret;
val &= ~ADT7411_CFG1_RESERVED_BIT1;
val |= ADT7411_CFG1_RESERVED_BIT3;
/* enable monitoring */
val |= ADT7411_CFG1_START_MONITOR;
return i2c_smbus_write_byte_data(data->client, ADT7411_REG_CFG1, val);
}
static const u32 adt7411_in_config[] = {
HWMON_I_INPUT,
HWMON_I_INPUT,
HWMON_I_INPUT,
HWMON_I_INPUT,
HWMON_I_INPUT,
HWMON_I_INPUT,
HWMON_I_INPUT,
HWMON_I_INPUT,
HWMON_I_INPUT,
0
};
static const struct hwmon_channel_info adt7411_in = {
.type = hwmon_in,
.config = adt7411_in_config,
};
static const u32 adt7411_temp_config[] = {
HWMON_T_INPUT,
HWMON_T_INPUT,
0
};
static const struct hwmon_channel_info adt7411_temp = {
.type = hwmon_temp,
.config = adt7411_temp_config,
};
static const struct hwmon_channel_info *adt7411_info[] = {
&adt7411_in,
&adt7411_temp,
NULL
};
static const struct hwmon_ops adt7411_hwmon_ops = {
.is_visible = adt7411_is_visible,
.read = adt7411_read,
};
static const struct hwmon_chip_info adt7411_chip_info = {
.ops = &adt7411_hwmon_ops,
.info = adt7411_info,
};
static int adt7411_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
struct device *dev = &client->dev;
struct adt7411_data *data;
struct device *hwmon_dev;
int ret;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
i2c_set_clientdata(client, data);
data->client = client;
mutex_init(&data->device_lock);
mutex_init(&data->update_lock);
ret = adt7411_init_device(data);
if (ret < 0)
return ret;
/* force update on first occasion */
data->next_update = jiffies;
hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name,
data,
&adt7411_chip_info,
adt7411_groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
static const struct i2c_device_id adt7411_id[] = {
{ "adt7411", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, adt7411_id);
static struct i2c_driver adt7411_driver = {
.driver = {
.name = "adt7411",
},
.probe = adt7411_probe,
.id_table = adt7411_id,
.detect = adt7411_detect,
.address_list = normal_i2c,
.class = I2C_CLASS_HWMON,
};
module_i2c_driver(adt7411_driver);
MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de> and "
"Wolfram Sang <w.sang@pengutronix.de>");
MODULE_DESCRIPTION("ADT7411 driver");
MODULE_LICENSE("GPL v2");