This acpi driver, based on previous work by Dmitry Ursegov (http://code.google.com/p/asusfan/), aims to provide a simple way to manage and monitor system fan speed on a (possibly large) variety of asus laptop models. As of now only the a8j, a8js and n50v[cn] platforms have been tested. Notebook Hardware Control Specs (www.pbus-167.org) can be followed to extend this support.
Temperature values and status parameters can be retrieved via sysfs entries; these values are also monitored by calculating a differential on a predefined set of samples, in order to show up how temperature is changing. An entry called temp_status is provided to have a quick look at this.
Fan Speed can also be arbitrary set by echoing the proper value into /sys/module/asus_fan/parameters/target_speed (usually 0-255). Althought this could be a dangerous operation, note that speed changing is based on autodetected temperatures, so this value could also be lost immediatly after being set or even ignored by the driver.
A brief look at the driver parameter follows:
# cat /sys/module/asus_fan/parameters/min_speed
0
# cat /sys/module/asus_fan/parameters/min_temp
0
# cat /sys/module/asus_fan/parameters/target_speed
-1
at the sampler behaviour:
# cat /sys/module/asus_fan/parameters/current_temp
70
# cat /sys/module/asus_fan/parameters/temp_status
stable
# cat /sys/module/asus_fan/parameters/temp_status
descending
# cat /sys/module/asus_fan/parameters/current_temp
62
# cat /sys/module/asus_fan/parameters/temp_status
ascending
# cat /sys/module/asus_fan/parameters/current_temp
66
# cat /sys/module/asus_fan/parameters/temp_status
ascending
# cat /sys/module/asus_fan/parameters/current_temp
68
# cat /sys/module/asus_fan/parameters/temp_status
descending
# cat /sys/module/asus_fan/parameters/current_temp
61
# cat /sys/module/asus_fan/parameters/temp_status
ascending
# cat /sys/module/asus_fan/parameters/current_temp
67
# cat /sys/module/asus_fan/parameters/temp_status
stable
# cat /sys/module/asus_fan/parameters/current_temp
67