Commit 87c33daa authored by Jean Delvare's avatar Jean Delvare

hwmon: (adm1031) Allow setting update rate

Based on earlier work by Ira W. Snyder.

The adm1031 chip is capable of using a runtime configurable sampling rate,
using the fan filter register. Add support for reading and setting the
update rate via sysfs.
Signed-off-by: default avatarJean Delvare <khali@linux-fr.org>
Acked-by: default avatarIra W. Snyder <iws@ovro.caltech.edu>
parent d2b847d4
......@@ -36,6 +36,7 @@
#define ADM1031_REG_FAN_DIV(nr) (0x20 + (nr))
#define ADM1031_REG_PWM (0x22)
#define ADM1031_REG_FAN_MIN(nr) (0x10 + (nr))
#define ADM1031_REG_FAN_FILTER (0x23)
#define ADM1031_REG_TEMP_OFFSET(nr) (0x0d + (nr))
#define ADM1031_REG_TEMP_MAX(nr) (0x14 + 4 * (nr))
......@@ -61,6 +62,9 @@
#define ADM1031_CONF2_TACH2_ENABLE 0x08
#define ADM1031_CONF2_TEMP_ENABLE(chan) (0x10 << (chan))
#define ADM1031_UPDATE_RATE_MASK 0x1c
#define ADM1031_UPDATE_RATE_SHIFT 2
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x2c, 0x2d, 0x2e, I2C_CLIENT_END };
......@@ -75,6 +79,7 @@ struct adm1031_data {
int chip_type;
char valid; /* !=0 if following fields are valid */
unsigned long last_updated; /* In jiffies */
unsigned int update_rate; /* In milliseconds */
/* The chan_select_table contains the possible configurations for
* auto fan control.
*/
......@@ -738,6 +743,57 @@ static SENSOR_DEVICE_ATTR(temp3_crit_alarm, S_IRUGO, show_alarm, NULL, 12);
static SENSOR_DEVICE_ATTR(temp3_fault, S_IRUGO, show_alarm, NULL, 13);
static SENSOR_DEVICE_ATTR(temp1_crit_alarm, S_IRUGO, show_alarm, NULL, 14);
/* Update Rate */
static const unsigned int update_rates[] = {
16000, 8000, 4000, 2000, 1000, 500, 250, 125,
};
static ssize_t show_update_rate(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct i2c_client *client = to_i2c_client(dev);
struct adm1031_data *data = i2c_get_clientdata(client);
return sprintf(buf, "%u\n", data->update_rate);
}
static ssize_t set_update_rate(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct i2c_client *client = to_i2c_client(dev);
struct adm1031_data *data = i2c_get_clientdata(client);
unsigned long val;
int i, err;
u8 reg;
err = strict_strtoul(buf, 10, &val);
if (err)
return err;
/* find the nearest update rate from the table */
for (i = 0; i < ARRAY_SIZE(update_rates) - 1; i++) {
if (val >= update_rates[i])
break;
}
/* if not found, we point to the last entry (lowest update rate) */
/* set the new update rate while preserving other settings */
reg = adm1031_read_value(client, ADM1031_REG_FAN_FILTER);
reg &= ~ADM1031_UPDATE_RATE_MASK;
reg |= i << ADM1031_UPDATE_RATE_SHIFT;
adm1031_write_value(client, ADM1031_REG_FAN_FILTER, reg);
mutex_lock(&data->update_lock);
data->update_rate = update_rates[i];
mutex_unlock(&data->update_lock);
return count;
}
static DEVICE_ATTR(update_rate, S_IRUGO | S_IWUSR, show_update_rate,
set_update_rate);
static struct attribute *adm1031_attributes[] = {
&sensor_dev_attr_fan1_input.dev_attr.attr,
&sensor_dev_attr_fan1_div.dev_attr.attr,
......@@ -774,6 +830,7 @@ static struct attribute *adm1031_attributes[] = {
&sensor_dev_attr_auto_fan1_min_pwm.dev_attr.attr,
&dev_attr_update_rate.attr,
&dev_attr_alarms.attr,
NULL
......@@ -900,6 +957,7 @@ static void adm1031_init_client(struct i2c_client *client)
{
unsigned int read_val;
unsigned int mask;
int i;
struct adm1031_data *data = i2c_get_clientdata(client);
mask = (ADM1031_CONF2_PWM1_ENABLE | ADM1031_CONF2_TACH1_ENABLE);
......@@ -919,18 +977,24 @@ static void adm1031_init_client(struct i2c_client *client)
ADM1031_CONF1_MONITOR_ENABLE);
}
/* Read the chip's update rate */
mask = ADM1031_UPDATE_RATE_MASK;
read_val = adm1031_read_value(client, ADM1031_REG_FAN_FILTER);
i = (read_val & mask) >> ADM1031_UPDATE_RATE_SHIFT;
data->update_rate = update_rates[i];
}
static struct adm1031_data *adm1031_update_device(struct device *dev)
{
struct i2c_client *client = to_i2c_client(dev);
struct adm1031_data *data = i2c_get_clientdata(client);
unsigned long next_update;
int chan;
mutex_lock(&data->update_lock);
if (time_after(jiffies, data->last_updated + HZ + HZ / 2)
|| !data->valid) {
next_update = data->last_updated + msecs_to_jiffies(data->update_rate);
if (time_after(jiffies, next_update) || !data->valid) {
dev_dbg(&client->dev, "Starting adm1031 update\n");
for (chan = 0;
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment