hwmon: (it87) Display fan outputs in automatic mode as such
The it87 driver doesn't yet support automatic fan control. Let it at
least tell the user when a fan output is in automatic mode. Also let
the user switch from automatic mode (possibly set by the BIOS) to
manual mode and back without losing the settings.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
diff --git a/drivers/hwmon/it87.c b/drivers/hwmon/it87.c
index 0ffe84d..49022bd 100644
--- a/drivers/hwmon/it87.c
+++ b/drivers/hwmon/it87.c
@@ -281,7 +281,14 @@
u32 alarms; /* Register encoding, combined */
u8 fan_main_ctrl; /* Register value */
u8 fan_ctl; /* Register value */
- u8 manual_pwm_ctl[3]; /* manual PWM value set by user */
+
+ /* The following 3 arrays correspond to the same registers. The
+ * meaning of bits 6-0 depends on the value of bit 7, and we want
+ * to preserve settings on mode changes, so we have to track all
+ * values separately. */
+ u8 pwm_ctrl[3]; /* Register value */
+ u8 pwm_duty[3]; /* Manual PWM value set by user (bit 6-0) */
+ u8 pwm_temp_map[3]; /* PWM to temp. chan. mapping (bits 1-0) */
};
static inline int has_16bit_fans(const struct it87_data *data)
@@ -531,6 +538,19 @@
show_sensor_offset(3);
/* 3 Fans */
+
+static int pwm_mode(const struct it87_data *data, int nr)
+{
+ int ctrl = data->fan_main_ctrl & (1 << nr);
+
+ if (ctrl == 0) /* Full speed */
+ return 0;
+ if (data->pwm_ctrl[nr] & 0x80) /* Automatic mode */
+ return 2;
+ else /* Manual mode */
+ return 1;
+}
+
static ssize_t show_fan(struct device *dev, struct device_attribute *attr,
char *buf)
{
@@ -567,7 +587,7 @@
int nr = sensor_attr->index;
struct it87_data *data = it87_update_device(dev);
- return sprintf(buf,"%d\n", (data->fan_main_ctrl & (1 << nr)) ? 1 : 0);
+ return sprintf(buf, "%d\n", pwm_mode(data, nr));
}
static ssize_t show_pwm(struct device *dev, struct device_attribute *attr,
char *buf)
@@ -576,7 +596,7 @@
int nr = sensor_attr->index;
struct it87_data *data = it87_update_device(dev);
- return sprintf(buf,"%d\n", data->manual_pwm_ctl[nr]);
+ return sprintf(buf, "%d\n", PWM_FROM_REG(data->pwm_duty[nr]));
}
static ssize_t show_pwm_freq(struct device *dev, struct device_attribute *attr,
char *buf)
@@ -660,6 +680,9 @@
struct it87_data *data = dev_get_drvdata(dev);
int val = simple_strtol(buf, NULL, 10);
+ if (val < 0 || val > 2)
+ return -EINVAL;
+
mutex_lock(&data->update_lock);
if (val == 0) {
@@ -670,15 +693,15 @@
/* set on/off mode */
data->fan_main_ctrl &= ~(1 << nr);
it87_write_value(data, IT87_REG_FAN_MAIN_CTRL, data->fan_main_ctrl);
- } else if (val == 1) {
+ } else {
+ if (val == 1) /* Manual mode */
+ data->pwm_ctrl[nr] = data->pwm_duty[nr];
+ else /* Automatic mode */
+ data->pwm_ctrl[nr] = 0x80 | data->pwm_temp_map[nr];
+ it87_write_value(data, IT87_REG_PWM(nr), data->pwm_ctrl[nr]);
/* set SmartGuardian mode */
data->fan_main_ctrl |= (1 << nr);
it87_write_value(data, IT87_REG_FAN_MAIN_CTRL, data->fan_main_ctrl);
- /* set saved pwm value, clear FAN_CTLX PWM mode bit */
- it87_write_value(data, IT87_REG_PWM(nr), PWM_TO_REG(data->manual_pwm_ctl[nr]));
- } else {
- mutex_unlock(&data->update_lock);
- return -EINVAL;
}
mutex_unlock(&data->update_lock);
@@ -697,9 +720,13 @@
return -EINVAL;
mutex_lock(&data->update_lock);
- data->manual_pwm_ctl[nr] = val;
- if (data->fan_main_ctrl & (1 << nr))
- it87_write_value(data, IT87_REG_PWM(nr), PWM_TO_REG(data->manual_pwm_ctl[nr]));
+ data->pwm_duty[nr] = PWM_TO_REG(val);
+ /* If we are in manual mode, write the duty cycle immediately;
+ * otherwise, just store it for later use. */
+ if (!(data->pwm_ctrl[nr] & 0x80)) {
+ data->pwm_ctrl[nr] = data->pwm_duty[nr];
+ it87_write_value(data, IT87_REG_PWM(nr), data->pwm_ctrl[nr]);
+ }
mutex_unlock(&data->update_lock);
return count;
}
@@ -1387,15 +1414,17 @@
int tmp, i;
u8 mask;
- /* initialize to sane defaults:
- * - if the chip is in manual pwm mode, this will be overwritten with
- * the actual settings on the chip (so in this case, initialization
- * is not needed)
- * - if in automatic or on/off mode, we could switch to manual mode,
- * read the registers and set manual_pwm_ctl accordingly, but currently
- * this is not implemented, so we initialize to something sane */
+ /* For each PWM channel:
+ * - If it is in automatic mode, setting to manual mode should set
+ * the fan to full speed by default.
+ * - If it is in manual mode, we need a mapping to temperature
+ * channels to use when later setting to automatic mode later.
+ * Use a 1:1 mapping by default (we are clueless.)
+ * In both cases, the value can (and should) be changed by the user
+ * prior to switching to a different mode. */
for (i = 0; i < 3; i++) {
- data->manual_pwm_ctl[i] = 0xff;
+ data->pwm_temp_map[i] = i;
+ data->pwm_duty[i] = 0x7f; /* Full speed */
}
/* Some chips seem to have default value 0xff for all limit
@@ -1461,30 +1490,21 @@
/* Fan input pins may be used for alternative functions */
data->has_fan &= ~sio_data->skip_fan;
- /* Set current fan mode registers and the default settings for the
- * other mode registers */
- for (i = 0; i < 3; i++) {
- if (data->fan_main_ctrl & (1 << i)) {
- /* pwm mode */
- tmp = it87_read_value(data, IT87_REG_PWM(i));
- if (tmp & 0x80) {
- /* automatic pwm - not yet implemented, but
- * leave the settings made by the BIOS alone
- * until a change is requested via the sysfs
- * interface */
- } else {
- /* manual pwm */
- data->manual_pwm_ctl[i] = PWM_FROM_REG(tmp);
- }
- }
- }
-
/* Start monitoring */
it87_write_value(data, IT87_REG_CONFIG,
(it87_read_value(data, IT87_REG_CONFIG) & 0x36)
| (update_vbat ? 0x41 : 0x01));
}
+static void it87_update_pwm_ctrl(struct it87_data *data, int nr)
+{
+ data->pwm_ctrl[nr] = it87_read_value(data, IT87_REG_PWM(nr));
+ if (data->pwm_ctrl[nr] & 0x80) /* Automatic mode */
+ data->pwm_temp_map[nr] = data->pwm_ctrl[nr] & 0x03;
+ else /* Manual mode */
+ data->pwm_duty[nr] = data->pwm_ctrl[nr] & 0x7f;
+}
+
static struct it87_data *it87_update_device(struct device *dev)
{
struct it87_data *data = dev_get_drvdata(dev);
@@ -1551,9 +1571,12 @@
it87_read_value(data, IT87_REG_ALARM1) |
(it87_read_value(data, IT87_REG_ALARM2) << 8) |
(it87_read_value(data, IT87_REG_ALARM3) << 16);
+
data->fan_main_ctrl = it87_read_value(data,
IT87_REG_FAN_MAIN_CTRL);
data->fan_ctl = it87_read_value(data, IT87_REG_FAN_CTL);
+ for (i = 0; i < 3; i++)
+ it87_update_pwm_ctrl(data, i);
data->sensor = it87_read_value(data, IT87_REG_TEMP_ENABLE);
/* The 8705 does not have VID capability.