The SMM interface does not differentiate between fan channels
and pwm channels, so each pwmX is associated with fanX_*.
Inform userspace programs of this with the pwmX_fan_channel
attribute.
Tested on a Dell Inspiron 3505.
Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
---
Documentation/hwmon/dell-smm-hwmon.rst | 1 +
drivers/hwmon/dell-smm-hwmon.c | 15 ++++++++++++---
2 files changed, 13 insertions(+), 3 deletions(-)
diff --git a/Documentation/hwmon/dell-smm-hwmon.rst b/Documentation/hwmon/dell-smm-hwmon.rst
index e5d85e40972c..2b0651c3f7c5 100644
--- a/Documentation/hwmon/dell-smm-hwmon.rst
+++ b/Documentation/hwmon/dell-smm-hwmon.rst
@@ -38,6 +38,7 @@ fan[1-3]_min RO Minimal Fan speed in RPM
fan[1-3]_max RO Maximal Fan speed in RPM
fan[1-3]_target RO Expected Fan speed in RPM
pwm[1-3] RW Control the fan PWM duty-cycle.
+pwm[1-3]_fan_channel RO Hints which PWM is connected to which fan
pwm1_enable WO Enable or disable automatic BIOS fan
control (not supported on all laptops,
see below for details).
diff --git a/drivers/hwmon/dell-smm-hwmon.c b/drivers/hwmon/dell-smm-hwmon.c
index 7f8d95dd2717..e6bf65d2ffc6 100644
--- a/drivers/hwmon/dell-smm-hwmon.c
+++ b/drivers/hwmon/dell-smm-hwmon.c
@@ -713,6 +713,11 @@ static umode_t dell_smm_is_visible(const void *drvdata, enum hwmon_sensor_types
if (data->fan[channel])
return 0644;
+ break;
+ case hwmon_pwm_fan_channel:
+ if (data->fan[channel])
+ return 0444;
+
break;
case hwmon_pwm_enable:
if (data->auto_fan)
@@ -800,6 +805,10 @@ static int dell_smm_read(struct device *dev, enum hwmon_sensor_types type, u32 a
*val = clamp_val(ret * data->i8k_pwm_mult, 0, 255);
+ return 0;
+ case hwmon_pwm_fan_channel:
+ *val = channel + 1;
+
return 0;
default:
break;
@@ -943,9 +952,9 @@ static const struct hwmon_channel_info *dell_smm_info[] = {
HWMON_F_TARGET
),
HWMON_CHANNEL_INFO(pwm,
- HWMON_PWM_INPUT | HWMON_PWM_ENABLE,
- HWMON_PWM_INPUT,
- HWMON_PWM_INPUT
+ HWMON_PWM_INPUT | HWMON_PWM_FAN_CHANNEL | HWMON_PWM_ENABLE,
+ HWMON_PWM_INPUT | HWMON_PWM_FAN_CHANNEL,
+ HWMON_PWM_INPUT | HWMON_PWM_FAN_CHANNEL
),
NULL
};
--
2.30.2
