linux-stable/drivers/hwmon/adt7x10.c
Lars-Peter Clausen 4b5e536b0e hwmon: (adt7x10) Add alarm interrupt support
This allows an userspace application to poll() on the alarm files to get
notified in case of a temperature threshold event.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Reviewed-by: Hartmut Knaack <knaack.h@gmx.de>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2013-04-07 21:16:38 -07:00

511 lines
13 KiB
C

/*
* adt7x10.c - Part of lm_sensors, Linux kernel modules for hardware
* monitoring
* This driver handles the ADT7410 and compatible digital temperature sensors.
* Hartmut Knaack <knaack.h@gmx.de> 2012-07-22
* based on lm75.c by Frodo Looijaard <frodol@dds.nl>
* and adt7410.c from iio-staging by Sonic Zhang <sonic.zhang@analog.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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/jiffies.h>
#include <linux/hwmon.h>
#include <linux/hwmon-sysfs.h>
#include <linux/err.h>
#include <linux/mutex.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include "adt7x10.h"
/*
* ADT7X10 status
*/
#define ADT7X10_STAT_T_LOW (1 << 4)
#define ADT7X10_STAT_T_HIGH (1 << 5)
#define ADT7X10_STAT_T_CRIT (1 << 6)
#define ADT7X10_STAT_NOT_RDY (1 << 7)
/*
* ADT7X10 config
*/
#define ADT7X10_FAULT_QUEUE_MASK (1 << 0 | 1 << 1)
#define ADT7X10_CT_POLARITY (1 << 2)
#define ADT7X10_INT_POLARITY (1 << 3)
#define ADT7X10_EVENT_MODE (1 << 4)
#define ADT7X10_MODE_MASK (1 << 5 | 1 << 6)
#define ADT7X10_FULL (0 << 5 | 0 << 6)
#define ADT7X10_PD (1 << 5 | 1 << 6)
#define ADT7X10_RESOLUTION (1 << 7)
/*
* ADT7X10 masks
*/
#define ADT7X10_T13_VALUE_MASK 0xFFF8
#define ADT7X10_T_HYST_MASK 0xF
/* straight from the datasheet */
#define ADT7X10_TEMP_MIN (-55000)
#define ADT7X10_TEMP_MAX 150000
/* Each client has this additional data */
struct adt7x10_data {
const struct adt7x10_ops *ops;
const char *name;
struct device *hwmon_dev;
struct mutex update_lock;
u8 config;
u8 oldconfig;
bool valid; /* true if registers valid */
unsigned long last_updated; /* In jiffies */
s16 temp[4]; /* Register values,
0 = input
1 = high
2 = low
3 = critical */
u8 hyst; /* hysteresis offset */
};
static int adt7x10_read_byte(struct device *dev, u8 reg)
{
struct adt7x10_data *d = dev_get_drvdata(dev);
return d->ops->read_byte(dev, reg);
}
static int adt7x10_write_byte(struct device *dev, u8 reg, u8 data)
{
struct adt7x10_data *d = dev_get_drvdata(dev);
return d->ops->write_byte(dev, reg, data);
}
static int adt7x10_read_word(struct device *dev, u8 reg)
{
struct adt7x10_data *d = dev_get_drvdata(dev);
return d->ops->read_word(dev, reg);
}
static int adt7x10_write_word(struct device *dev, u8 reg, u16 data)
{
struct adt7x10_data *d = dev_get_drvdata(dev);
return d->ops->write_word(dev, reg, data);
}
static const u8 ADT7X10_REG_TEMP[4] = {
ADT7X10_TEMPERATURE, /* input */
ADT7X10_T_ALARM_HIGH, /* high */
ADT7X10_T_ALARM_LOW, /* low */
ADT7X10_T_CRIT, /* critical */
};
static irqreturn_t adt7x10_irq_handler(int irq, void *private)
{
struct device *dev = private;
int status;
status = adt7x10_read_byte(dev, ADT7X10_STATUS);
if (status < 0)
return IRQ_HANDLED;
if (status & ADT7X10_STAT_T_HIGH)
sysfs_notify(&dev->kobj, NULL, "temp1_max_alarm");
if (status & ADT7X10_STAT_T_LOW)
sysfs_notify(&dev->kobj, NULL, "temp1_min_alarm");
if (status & ADT7X10_STAT_T_CRIT)
sysfs_notify(&dev->kobj, NULL, "temp1_crit_alarm");
return IRQ_HANDLED;
}
static int adt7x10_temp_ready(struct device *dev)
{
int i, status;
for (i = 0; i < 6; i++) {
status = adt7x10_read_byte(dev, ADT7X10_STATUS);
if (status < 0)
return status;
if (!(status & ADT7X10_STAT_NOT_RDY))
return 0;
msleep(60);
}
return -ETIMEDOUT;
}
static int adt7x10_update_temp(struct device *dev)
{
struct adt7x10_data *data = dev_get_drvdata(dev);
int ret = 0;
mutex_lock(&data->update_lock);
if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
|| !data->valid) {
int temp;
dev_dbg(dev, "Starting update\n");
ret = adt7x10_temp_ready(dev); /* check for new value */
if (ret)
goto abort;
temp = adt7x10_read_word(dev, ADT7X10_REG_TEMP[0]);
if (temp < 0) {
ret = temp;
dev_dbg(dev, "Failed to read value: reg %d, error %d\n",
ADT7X10_REG_TEMP[0], ret);
goto abort;
}
data->temp[0] = temp;
data->last_updated = jiffies;
data->valid = true;
}
abort:
mutex_unlock(&data->update_lock);
return ret;
}
static int adt7x10_fill_cache(struct device *dev)
{
struct adt7x10_data *data = dev_get_drvdata(dev);
int ret;
int i;
for (i = 1; i < ARRAY_SIZE(data->temp); i++) {
ret = adt7x10_read_word(dev, ADT7X10_REG_TEMP[i]);
if (ret < 0) {
dev_dbg(dev, "Failed to read value: reg %d, error %d\n",
ADT7X10_REG_TEMP[i], ret);
return ret;
}
data->temp[i] = ret;
}
ret = adt7x10_read_byte(dev, ADT7X10_T_HYST);
if (ret < 0) {
dev_dbg(dev, "Failed to read value: reg %d, error %d\n",
ADT7X10_T_HYST, ret);
return ret;
}
data->hyst = ret;
return 0;
}
static s16 ADT7X10_TEMP_TO_REG(long temp)
{
return DIV_ROUND_CLOSEST(clamp_val(temp, ADT7X10_TEMP_MIN,
ADT7X10_TEMP_MAX) * 128, 1000);
}
static int ADT7X10_REG_TO_TEMP(struct adt7x10_data *data, s16 reg)
{
/* in 13 bit mode, bits 0-2 are status flags - mask them out */
if (!(data->config & ADT7X10_RESOLUTION))
reg &= ADT7X10_T13_VALUE_MASK;
/*
* temperature is stored in twos complement format, in steps of
* 1/128°C
*/
return DIV_ROUND_CLOSEST(reg * 1000, 128);
}
/*-----------------------------------------------------------------------*/
/* sysfs attributes for hwmon */
static ssize_t adt7x10_show_temp(struct device *dev,
struct device_attribute *da,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct adt7x10_data *data = dev_get_drvdata(dev);
if (attr->index == 0) {
int ret;
ret = adt7x10_update_temp(dev);
if (ret)
return ret;
}
return sprintf(buf, "%d\n", ADT7X10_REG_TO_TEMP(data,
data->temp[attr->index]));
}
static ssize_t adt7x10_set_temp(struct device *dev,
struct device_attribute *da,
const char *buf, size_t count)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct adt7x10_data *data = dev_get_drvdata(dev);
int nr = attr->index;
long temp;
int ret;
ret = kstrtol(buf, 10, &temp);
if (ret)
return ret;
mutex_lock(&data->update_lock);
data->temp[nr] = ADT7X10_TEMP_TO_REG(temp);
ret = adt7x10_write_word(dev, ADT7X10_REG_TEMP[nr], data->temp[nr]);
if (ret)
count = ret;
mutex_unlock(&data->update_lock);
return count;
}
static ssize_t adt7x10_show_t_hyst(struct device *dev,
struct device_attribute *da,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
struct adt7x10_data *data = dev_get_drvdata(dev);
int nr = attr->index;
int hyst;
hyst = (data->hyst & ADT7X10_T_HYST_MASK) * 1000;
/*
* hysteresis is stored as a 4 bit offset in the device, convert it
* to an absolute value
*/
if (nr == 2) /* min has positive offset, others have negative */
hyst = -hyst;
return sprintf(buf, "%d\n",
ADT7X10_REG_TO_TEMP(data, data->temp[nr]) - hyst);
}
static ssize_t adt7x10_set_t_hyst(struct device *dev,
struct device_attribute *da,
const char *buf, size_t count)
{
struct adt7x10_data *data = dev_get_drvdata(dev);
int limit, ret;
long hyst;
ret = kstrtol(buf, 10, &hyst);
if (ret)
return ret;
/* convert absolute hysteresis value to a 4 bit delta value */
limit = ADT7X10_REG_TO_TEMP(data, data->temp[1]);
hyst = clamp_val(hyst, ADT7X10_TEMP_MIN, ADT7X10_TEMP_MAX);
data->hyst = clamp_val(DIV_ROUND_CLOSEST(limit - hyst, 1000),
0, ADT7X10_T_HYST_MASK);
ret = adt7x10_write_byte(dev, ADT7X10_T_HYST, data->hyst);
if (ret)
return ret;
return count;
}
static ssize_t adt7x10_show_alarm(struct device *dev,
struct device_attribute *da,
char *buf)
{
struct sensor_device_attribute *attr = to_sensor_dev_attr(da);
int ret;
ret = adt7x10_read_byte(dev, ADT7X10_STATUS);
if (ret < 0)
return ret;
return sprintf(buf, "%d\n", !!(ret & attr->index));
}
static ssize_t adt7x10_show_name(struct device *dev,
struct device_attribute *da,
char *buf)
{
struct adt7x10_data *data = dev_get_drvdata(dev);
return sprintf(buf, "%s\n", data->name);
}
static SENSOR_DEVICE_ATTR(temp1_input, S_IRUGO, adt7x10_show_temp, NULL, 0);
static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO,
adt7x10_show_temp, adt7x10_set_temp, 1);
static SENSOR_DEVICE_ATTR(temp1_min, S_IWUSR | S_IRUGO,
adt7x10_show_temp, adt7x10_set_temp, 2);
static SENSOR_DEVICE_ATTR(temp1_crit, S_IWUSR | S_IRUGO,
adt7x10_show_temp, adt7x10_set_temp, 3);
static SENSOR_DEVICE_ATTR(temp1_max_hyst, S_IWUSR | S_IRUGO,
adt7x10_show_t_hyst, adt7x10_set_t_hyst, 1);
static SENSOR_DEVICE_ATTR(temp1_min_hyst, S_IRUGO,
adt7x10_show_t_hyst, NULL, 2);
static SENSOR_DEVICE_ATTR(temp1_crit_hyst, S_IRUGO,
adt7x10_show_t_hyst, NULL, 3);
static SENSOR_DEVICE_ATTR(temp1_min_alarm, S_IRUGO, adt7x10_show_alarm,
NULL, ADT7X10_STAT_T_LOW);
static SENSOR_DEVICE_ATTR(temp1_max_alarm, S_IRUGO, adt7x10_show_alarm,
NULL, ADT7X10_STAT_T_HIGH);
static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, adt7x10_show_alarm,
NULL, ADT7X10_STAT_T_CRIT);
static DEVICE_ATTR(name, S_IRUGO, adt7x10_show_name, NULL);
static struct attribute *adt7x10_attributes[] = {
&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_crit.dev_attr.attr,
&sensor_dev_attr_temp1_max_hyst.dev_attr.attr,
&sensor_dev_attr_temp1_min_hyst.dev_attr.attr,
&sensor_dev_attr_temp1_crit_hyst.dev_attr.attr,
&sensor_dev_attr_temp1_min_alarm.dev_attr.attr,
&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp1_crit_alarm.dev_attr.attr,
NULL
};
static const struct attribute_group adt7x10_group = {
.attrs = adt7x10_attributes,
};
int adt7x10_probe(struct device *dev, const char *name, int irq,
const struct adt7x10_ops *ops)
{
struct adt7x10_data *data;
int ret;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->ops = ops;
data->name = name;
dev_set_drvdata(dev, data);
mutex_init(&data->update_lock);
/* configure as specified */
ret = adt7x10_read_byte(dev, ADT7X10_CONFIG);
if (ret < 0) {
dev_dbg(dev, "Can't read config? %d\n", ret);
return ret;
}
data->oldconfig = ret;
/*
* Set to 16 bit resolution, continous conversion and comparator mode.
*/
data->config = data->oldconfig;
data->config &= ~(ADT7X10_MODE_MASK | ADT7X10_CT_POLARITY |
ADT7X10_INT_POLARITY);
data->config |= ADT7X10_FULL | ADT7X10_RESOLUTION | ADT7X10_EVENT_MODE;
if (data->config != data->oldconfig) {
ret = adt7x10_write_byte(dev, ADT7X10_CONFIG, data->config);
if (ret)
return ret;
}
dev_dbg(dev, "Config %02x\n", data->config);
ret = adt7x10_fill_cache(dev);
if (ret)
goto exit_restore;
/* Register sysfs hooks */
ret = sysfs_create_group(&dev->kobj, &adt7x10_group);
if (ret)
goto exit_restore;
/*
* The I2C device will already have it's own 'name' attribute, but for
* the SPI device we need to register it. name will only be non NULL if
* the device doesn't register the 'name' attribute on its own.
*/
if (name) {
ret = device_create_file(dev, &dev_attr_name);
if (ret)
goto exit_remove;
}
data->hwmon_dev = hwmon_device_register(dev);
if (IS_ERR(data->hwmon_dev)) {
ret = PTR_ERR(data->hwmon_dev);
goto exit_remove_name;
}
if (irq > 0) {
ret = request_threaded_irq(irq, NULL, adt7x10_irq_handler,
IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
dev_name(dev), dev);
if (ret)
goto exit_hwmon_device_unregister;
}
return 0;
exit_hwmon_device_unregister:
hwmon_device_unregister(data->hwmon_dev);
exit_remove_name:
if (name)
device_remove_file(dev, &dev_attr_name);
exit_remove:
sysfs_remove_group(&dev->kobj, &adt7x10_group);
exit_restore:
adt7x10_write_byte(dev, ADT7X10_CONFIG, data->oldconfig);
return ret;
}
EXPORT_SYMBOL_GPL(adt7x10_probe);
int adt7x10_remove(struct device *dev, int irq)
{
struct adt7x10_data *data = dev_get_drvdata(dev);
if (irq > 0)
free_irq(irq, dev);
hwmon_device_unregister(data->hwmon_dev);
if (data->name)
device_remove_file(dev, &dev_attr_name);
sysfs_remove_group(&dev->kobj, &adt7x10_group);
if (data->oldconfig != data->config)
adt7x10_write_byte(dev, ADT7X10_CONFIG, data->oldconfig);
return 0;
}
EXPORT_SYMBOL_GPL(adt7x10_remove);
#ifdef CONFIG_PM_SLEEP
static int adt7x10_suspend(struct device *dev)
{
struct adt7x10_data *data = dev_get_drvdata(dev);
return adt7x10_write_byte(dev, ADT7X10_CONFIG,
data->config | ADT7X10_PD);
}
static int adt7x10_resume(struct device *dev)
{
struct adt7x10_data *data = dev_get_drvdata(dev);
return adt7x10_write_byte(dev, ADT7X10_CONFIG, data->config);
}
SIMPLE_DEV_PM_OPS(adt7x10_dev_pm_ops, adt7x10_suspend, adt7x10_resume);
EXPORT_SYMBOL_GPL(adt7x10_dev_pm_ops);
#endif /* CONFIG_PM_SLEEP */
MODULE_AUTHOR("Hartmut Knaack");
MODULE_DESCRIPTION("ADT7410/ADT7420, ADT7310/ADT7320 common code");
MODULE_LICENSE("GPL");