From: Armin Wolf <W_Armin@xxxxxx>
For allowing tools like i8kutils to query the fan state
without having to rely on the deprecated /proc/i8k interface,
they need to scale the pwm values (0 - 255) back to the
real hardware values (0 - 2/3).
Show fan_max in sysfs to allow for such a scenario.
Tested on a Dell Latitude C600.
Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
---
drivers/hwmon/dell-smm-hwmon.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/drivers/hwmon/dell-smm-hwmon.c b/drivers/hwmon/dell-smm-hwmon.c
index 774c1b0715d9..6d3fd4f0f99d 100644
--- a/drivers/hwmon/dell-smm-hwmon.c
+++ b/drivers/hwmon/dell-smm-hwmon.c
@@ -107,7 +107,7 @@ module_param(fan_mult, uint, 0);
MODULE_PARM_DESC(fan_mult, "Factor to multiply fan speed with (default: autodetect)");
static uint fan_max;
-module_param(fan_max, uint, 0);
+module_param(fan_max, uint, 0444);
MODULE_PARM_DESC(fan_max, "Maximum configurable fan speed (default: autodetect)");
struct smm_regs {
@@ -1245,7 +1245,10 @@ static int __init dell_smm_probe(struct platform_device *pdev)
fan_max = conf->fan_max;
}
- data->i8k_fan_max = fan_max ? : I8K_FAN_HIGH; /* Must not be 0 */
+ if (!fan_max) /* Must not be 0*/
+ fan_max = I8K_FAN_HIGH;
+
+ data->i8k_fan_max = fan_max;
data->i8k_pwm_mult = DIV_ROUND_UP(255, data->i8k_fan_max);
fan_control = dmi_first_match(i8k_whitelist_fan_control);
--
2.20.1
