diff --git a/Documentation/hwmon/adt7470 b/Documentation/hwmon/adt7470
index 75d13ca147ccbe7234a85d4bf40ac715d3fa9c4d..8ce4aa0a0f5500cc5a6fbecc67644d4e1600dcf7 100644
--- a/Documentation/hwmon/adt7470
+++ b/Documentation/hwmon/adt7470
@@ -31,15 +31,11 @@ Each of the measured inputs (temperature, fan speed) has corresponding high/low
limit values. The ADT7470 will signal an ALARM if any measured value exceeds
either limit.
-The ADT7470 DOES NOT sample all inputs continuously. A single pin on the
-ADT7470 is connected to a multitude of thermal diodes, but the chip must be
-instructed explicitly to read the multitude of diodes. If you want to use
-automatic fan control mode, you must manually read any of the temperature
-sensors or the fan control algorithm will not run. The chip WILL NOT DO THIS
-AUTOMATICALLY; this must be done from userspace. This may be a bug in the chip
-design, given that many other AD chips take care of this. The driver will not
-read the registers more often than once every 5 seconds. Further,
-configuration data is only read once per minute.
+The ADT7470 samples all inputs continuously. A kernel thread is started up for
+the purpose of periodically querying the temperature sensors, thus allowing the
+automatic fan pwm control to set the fan speed. The driver will not read the
+registers more often than once every 5 seconds. Further, configuration data is
+only read once per minute.
Special Features
----------------
@@ -72,5 +68,6 @@ pwm#_auto_point2_temp.
Notes
-----
-As stated above, the temperature inputs must be read periodically from
-userspace in order for the automatic pwm algorithm to run.
+The temperature inputs no longer need to be read periodically from userspace in
+order for the automatic pwm algorithm to run. This was the case for earlier
+versions of the driver.
diff --git a/drivers/hwmon/adt7470.c b/drivers/hwmon/adt7470.c
index ab8d5ebc9f75e25838d3dbe80c5ef8100d426f53..633e1a1e9d79843f1d8feebbb276e737903b685f 100644
--- a/drivers/hwmon/adt7470.c
+++ b/drivers/hwmon/adt7470.c
@@ -28,6 +28,7 @@
#include <linux/mutex.h>
#include <linux/delay.h>
#include <linux/log2.h>
+#include <linux/kthread.h>
/* Addresses to scan */
static const unsigned short normal_i2c[] = { 0x2C, 0x2E, 0x2F, I2C_CLIENT_END };
@@ -132,6 +133,9 @@ I2C_CLIENT_INSMOD_1(adt7470);
/* Wait at least 200ms per sensor for 10 sensors */
#define TEMP_COLLECTION_TIME 2000
+/* auto update thing won't fire more than every 2s */
+#define AUTO_UPDATE_INTERVAL 2000
+
/* datasheet says to divide this number by the fan reading to get fan rpm */
#define FAN_PERIOD_TO_RPM(x) ((90000 * 60) / (x))
#define FAN_RPM_TO_PERIOD FAN_PERIOD_TO_RPM
@@ -148,6 +152,7 @@ struct adt7470_data {
unsigned long limits_last_updated; /* In jiffies */
int num_temp_sensors; /* -1 = probe */
+ int temperatures_probed;
s8 temp[ADT7470_TEMP_COUNT];
s8 temp_min[ADT7470_TEMP_COUNT];
@@ -164,6 +169,10 @@ struct adt7470_data {
u8 pwm_min[ADT7470_PWM_COUNT];
s8 pwm_tmin[ADT7470_PWM_COUNT];
u8 pwm_auto_temp[ADT7470_PWM_COUNT];
+
+ struct task_struct *auto_update;
+ struct completion auto_update_stop;
+ unsigned int auto_update_interval;
};
static int adt7470_probe(struct i2c_client *client,
@@ -221,19 +230,13 @@ static void adt7470_init_client(struct i2c_client *client)
}
}
-static struct adt7470_data *adt7470_update_device(struct device *dev)
+/* Probe for temperature sensors. Assumes lock is held */
+static int adt7470_read_temperatures(struct i2c_client *client,
+ struct adt7470_data *data)
{
- struct i2c_client *client = to_i2c_client(dev);
- struct adt7470_data *data = i2c_get_clientdata(client);
- unsigned long local_jiffies = jiffies;
- u8 cfg, pwm[4], pwm_cfg[2];
+ unsigned long res;
int i;
-
- mutex_lock(&data->lock);
- if (time_before(local_jiffies, data->sensors_last_updated +
- SENSOR_REFRESH_INTERVAL)
- && data->sensors_valid)
- goto no_sensor_update;
+ u8 cfg, pwm[4], pwm_cfg[2];
/* save pwm[1-4] config register */
pwm_cfg[0] = i2c_smbus_read_byte_data(client, ADT7470_REG_PWM_CFG(0));
@@ -259,9 +262,9 @@ static struct adt7470_data *adt7470_update_device(struct device *dev)
i2c_smbus_write_byte_data(client, ADT7470_REG_CFG, cfg);
/* Delay is 200ms * number of temp sensors. */
- msleep((data->num_temp_sensors >= 0 ?
- data->num_temp_sensors * 200 :
- TEMP_COLLECTION_TIME));
+ res = msleep_interruptible((data->num_temp_sensors >= 0 ?
+ data->num_temp_sensors * 200 :
+ TEMP_COLLECTION_TIME));
/* done reading temperature sensors */
cfg = i2c_smbus_read_byte_data(client, ADT7470_REG_CFG);
@@ -272,15 +275,81 @@ static struct adt7470_data *adt7470_update_device(struct device *dev)
i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_CFG(0), pwm_cfg[0]);
i2c_smbus_write_byte_data(client, ADT7470_REG_PWM_CFG(2), pwm_cfg[1]);
- for (i = 0; i < ADT7470_TEMP_COUNT; i++)
+ if (res) {
+ printk(KERN_ERR "ha ha, interrupted");
+ return -EAGAIN;
+ }
+
+ /* Only count fans if we have to */
+ if (data->num_temp_sensors >= 0)
+ return 0;
+
+ for (i = 0; i < ADT7470_TEMP_COUNT; i++) {
data->temp[i] = i2c_smbus_read_byte_data(client,
ADT7470_TEMP_REG(i));
+ if (data->temp[i])
+ data->num_temp_sensors = i + 1;
+ }
+ data->temperatures_probed = 1;
+ return 0;
+}
- /* Figure out the number of temp sensors */
- if (data->num_temp_sensors < 0)
+static int adt7470_update_thread(void *p)
+{
+ struct i2c_client *client = p;
+ struct adt7470_data *data = i2c_get_clientdata(client);
+
+ while (!kthread_should_stop()) {
+ mutex_lock(&data->lock);
+ adt7470_read_temperatures(client, data);
+ mutex_unlock(&data->lock);
+ if (kthread_should_stop())
+ break;
+ msleep_interruptible(data->auto_update_interval);
+ }
+
+ complete_all(&data->auto_update_stop);
+ return 0;
+}
+
+static struct adt7470_data *adt7470_update_device(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct adt7470_data *data = i2c_get_clientdata(client);
+ unsigned long local_jiffies = jiffies;
+ u8 cfg;
+ int i;
+ int need_sensors = 1;
+ int need_limits = 1;
+
+ /*
+ * Figure out if we need to update the shadow registers.
+ * Lockless means that we may occasionally report out of
+ * date data.
+ */
+ if (time_before(local_jiffies, data->sensors_last_updated +
+ SENSOR_REFRESH_INTERVAL) &&
+ data->sensors_valid)
+ need_sensors = 0;
+
+ if (time_before(local_jiffies, data->limits_last_updated +
+ LIMIT_REFRESH_INTERVAL) &&
+ data->limits_valid)
+ need_limits = 0;
+
+ if (!need_sensors && !need_limits)
+ return data;
+
+ mutex_lock(&data->lock);
+ if (!need_sensors)
+ goto no_sensor_update;
+
+ if (!data->temperatures_probed)
+ adt7470_read_temperatures(client, data);
+ else
for (i = 0; i < ADT7470_TEMP_COUNT; i++)
- if (data->temp[i])
- data->num_temp_sensors = i + 1;
+ data->temp[i] = i2c_smbus_read_byte_data(client,
+ ADT7470_TEMP_REG(i));
for (i = 0; i < ADT7470_FAN_COUNT; i++)
data->fan[i] = adt7470_read_word_data(client,
@@ -329,9 +398,7 @@ static struct adt7470_data *adt7470_update_device(struct device *dev)
data->sensors_valid = 1;
no_sensor_update:
- if (time_before(local_jiffies, data->limits_last_updated +
- LIMIT_REFRESH_INTERVAL)
- && data->limits_valid)
+ if (!need_limits)
goto out;
for (i = 0; i < ADT7470_TEMP_COUNT; i++) {
@@ -365,6 +432,35 @@ static struct adt7470_data *adt7470_update_device(struct device *dev)
return data;
}
+static ssize_t show_auto_update_interval(struct device *dev,
+ struct device_attribute *devattr,
+ char *buf)
+{
+ struct adt7470_data *data = adt7470_update_device(dev);
+ return sprintf(buf, "%d\n", data->auto_update_interval);
+}
+
+static ssize_t set_auto_update_interval(struct device *dev,
+ struct device_attribute *devattr,
+ const char *buf,
+ size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct adt7470_data *data = i2c_get_clientdata(client);
+ long temp;
+
+ if (strict_strtol(buf, 10, &temp))
+ return -EINVAL;
+
+ temp = SENSORS_LIMIT(temp, 0, 60000);
+
+ mutex_lock(&data->lock);
+ data->auto_update_interval = temp;
+ mutex_unlock(&data->lock);
+
+ return count;
+}
+
static ssize_t show_num_temp_sensors(struct device *dev,
struct device_attribute *devattr,
char *buf)
@@ -389,6 +485,8 @@ static ssize_t set_num_temp_sensors(struct device *dev,
mutex_lock(&data->lock);
data->num_temp_sensors = temp;
+ if (temp < 0)
+ data->temperatures_probed = 0;
mutex_unlock(&data->lock);
return count;
@@ -862,6 +960,8 @@ static ssize_t show_alarm(struct device *dev,
static DEVICE_ATTR(alarm_mask, S_IRUGO, show_alarm_mask, NULL);
static DEVICE_ATTR(num_temp_sensors, S_IWUSR | S_IRUGO, show_num_temp_sensors,
set_num_temp_sensors);
+static DEVICE_ATTR(auto_update_interval, S_IWUSR | S_IRUGO,
+ show_auto_update_interval, set_auto_update_interval);
static SENSOR_DEVICE_ATTR(temp1_max, S_IWUSR | S_IRUGO, show_temp_max,
set_temp_max, 0);
@@ -1035,6 +1135,7 @@ static struct attribute *adt7470_attr[] =
{
&dev_attr_alarm_mask.attr,
&dev_attr_num_temp_sensors.attr,
+ &dev_attr_auto_update_interval.attr,
&sensor_dev_attr_temp1_max.dev_attr.attr,
&sensor_dev_attr_temp2_max.dev_attr.attr,
&sensor_dev_attr_temp3_max.dev_attr.attr,
@@ -1168,6 +1269,7 @@ static int adt7470_probe(struct i2c_client *client,
}
data->num_temp_sensors = -1;
+ data->auto_update_interval = AUTO_UPDATE_INTERVAL;
i2c_set_clientdata(client, data);
mutex_init(&data->lock);
@@ -1188,8 +1290,16 @@ static int adt7470_probe(struct i2c_client *client,
goto exit_remove;
}
+ init_completion(&data->auto_update_stop);
+ data->auto_update = kthread_run(adt7470_update_thread, client,
+ dev_name(data->hwmon_dev));
+ if (IS_ERR(data->auto_update))
+ goto exit_unregister;
+
return 0;
+exit_unregister:
+ hwmon_device_unregister(data->hwmon_dev);
exit_remove:
sysfs_remove_group(&client->dev.kobj, &data->attrs);
exit_free:
@@ -1202,6 +1312,8 @@ static int adt7470_remove(struct i2c_client *client)
{
struct adt7470_data *data = i2c_get_clientdata(client);
+ kthread_stop(data->auto_update);
+ wait_for_completion(&data->auto_update_stop);
hwmon_device_unregister(data->hwmon_dev);
sysfs_remove_group(&client->dev.kobj, &data->attrs);
kfree(data);