hwmon: (lm63) Add support for update_interval sysfs attribute
The update interval is configurable on LM63 and compatibles. Add
support for it.
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/hwmon/lm63.c b/drivers/hwmon/lm63.c
index a9e6212..5f6da52 100644
--- a/drivers/hwmon/lm63.c
+++ b/drivers/hwmon/lm63.c
@@ -61,6 +61,7 @@
*/
#define LM63_REG_CONFIG1 0x03
+#define LM63_REG_CONVRATE 0x04
#define LM63_REG_CONFIG2 0xBF
#define LM63_REG_CONFIG_FAN 0x4A
@@ -96,6 +97,11 @@
#define LM96163_REG_REMOTE_TEMP_U_LSB 0x32
#define LM96163_REG_CONFIG_ENHANCED 0x45
+#define LM63_MAX_CONVRATE 9
+
+#define LM63_MAX_CONVRATE_HZ 32
+#define LM96163_MAX_CONVRATE_HZ 26
+
/*
* Conversions and various macros
* For tachometer counts, the LM63 uses 16-bit values.
@@ -132,6 +138,9 @@
(val) >= 127000 ? 127 : \
((val) + 500) / 1000)
+#define UPDATE_INTERVAL(max, rate) \
+ ((1000 << (LM63_MAX_CONVRATE - (rate))) / (max))
+
/*
* Functions declaration
*/
@@ -180,9 +189,12 @@
struct mutex update_lock;
char valid; /* zero until following fields are valid */
unsigned long last_updated; /* in jiffies */
- int kind;
+ enum chips kind;
int temp2_offset;
+ int update_interval; /* in milliseconds */
+ int max_convrate_hz;
+
/* registers values */
u8 config, config_fan;
u16 fan[2]; /* 0: input
@@ -449,6 +461,58 @@
return count;
}
+/*
+ * Set conversion rate.
+ * client->update_lock must be held when calling this function.
+ */
+static void lm63_set_convrate(struct i2c_client *client, struct lm63_data *data,
+ unsigned int interval)
+{
+ int i;
+ unsigned int update_interval;
+
+ /* Shift calculations to avoid rounding errors */
+ interval <<= 6;
+
+ /* find the nearest update rate */
+ update_interval = (1 << (LM63_MAX_CONVRATE + 6)) * 1000
+ / data->max_convrate_hz;
+ for (i = 0; i < LM63_MAX_CONVRATE; i++, update_interval >>= 1)
+ if (interval >= update_interval * 3 / 4)
+ break;
+
+ i2c_smbus_write_byte_data(client, LM63_REG_CONVRATE, i);
+ data->update_interval = UPDATE_INTERVAL(data->max_convrate_hz, i);
+}
+
+static ssize_t show_update_interval(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct lm63_data *data = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%u\n", data->update_interval);
+}
+
+static ssize_t set_update_interval(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct lm63_data *data = i2c_get_clientdata(client);
+ unsigned long val;
+ int err;
+
+ err = kstrtoul(buf, 10, &val);
+ if (err)
+ return err;
+
+ mutex_lock(&data->update_lock);
+ lm63_set_convrate(client, data, SENSORS_LIMIT(val, 0, 100000));
+ mutex_unlock(&data->update_lock);
+
+ return count;
+}
+
static ssize_t show_alarms(struct device *dev, struct device_attribute *dummy,
char *buf)
{
@@ -499,6 +563,9 @@
/* Raw alarm file for compatibility */
static DEVICE_ATTR(alarms, S_IRUGO, show_alarms, NULL);
+static DEVICE_ATTR(update_interval, S_IRUGO | S_IWUSR, show_update_interval,
+ set_update_interval);
+
static struct attribute *lm63_attributes[] = {
&dev_attr_pwm1.attr,
&dev_attr_pwm1_enable.attr,
@@ -517,6 +584,7 @@
&sensor_dev_attr_temp2_max_alarm.dev_attr.attr,
&sensor_dev_attr_temp1_max_alarm.dev_attr.attr,
&dev_attr_alarms.attr,
+ &dev_attr_update_interval.attr,
NULL
};
@@ -669,6 +737,7 @@
static void lm63_init_client(struct i2c_client *client)
{
struct lm63_data *data = i2c_get_clientdata(client);
+ u8 convrate;
data->config = i2c_smbus_read_byte_data(client, LM63_REG_CONFIG1);
data->config_fan = i2c_smbus_read_byte_data(client,
@@ -687,6 +756,21 @@
if (data->pwm1_freq == 0)
data->pwm1_freq = 1;
+ switch (data->kind) {
+ case lm63:
+ case lm64:
+ data->max_convrate_hz = LM63_MAX_CONVRATE_HZ;
+ break;
+ case lm96163:
+ data->max_convrate_hz = LM96163_MAX_CONVRATE_HZ;
+ break;
+ }
+ convrate = i2c_smbus_read_byte_data(client, LM63_REG_CONVRATE);
+ if (unlikely(convrate > LM63_MAX_CONVRATE))
+ convrate = LM63_MAX_CONVRATE;
+ data->update_interval = UPDATE_INTERVAL(data->max_convrate_hz,
+ convrate);
+
/*
* For LM96163, check if high resolution PWM
* and unsigned temperature format is enabled.
@@ -730,10 +814,14 @@
{
struct i2c_client *client = to_i2c_client(dev);
struct lm63_data *data = i2c_get_clientdata(client);
+ unsigned long next_update;
mutex_lock(&data->update_lock);
- if (time_after(jiffies, data->last_updated + HZ) || !data->valid) {
+ next_update = data->last_updated
+ + msecs_to_jiffies(data->update_interval) + 1;
+
+ if (time_after(jiffies, next_update) || !data->valid) {
if (data->config & 0x04) { /* tachometer enabled */
/* order matters for fan1_input */
data->fan[0] = i2c_smbus_read_byte_data(client,