Description of problem: Thinkfan no longer works.

[sudhir@fedora ~]$ sudo thinkfan -n

WARNING: Using default fan control in /proc/acpi/ibm/fan.

WARNING: You're using simple temperature limits without correction values, and your fan will only start at 55 °C. This can be dangerous for your hard drive.

setfan_ibm: Error writing to /proc/acpi/ibm/fan: Invalid argument
Cleaning up and resetting fan control.

systemctl status thinkfan.service -l
● thinkfan.service - simple and lightweight fan control program                                                                                                         
   Loaded: loaded (/usr/lib/systemd/system/thinkfan.service; enabled; vendor preset: disabled)                                                                          
   Active: inactive (dead) since Mon 2015-07-27 10:34:54 IST; 2h 33min ago                                                                                              
  Process: 733 ExecStart=/usr/sbin/thinkfan (code=exited, status=0/SUCCESS)                                                                                             
 Main PID: 741 (code=exited, status=0/SUCCESS)                                                                                                                          
                                                                                                                                                                        
Jul 27 10:34:29 fedora systemd[1]: Starting simple and lightweight fan control program...                                                                               
Jul 27 10:34:29 fedora thinkfan[733]: thinkfan 0.9.1 starting...                                                                                                        
Jul 27 10:34:29 fedora thinkfan[733]: WARNING: Using default fan control in /proc/acpi/ibm/fan.                                                                         
Jul 27 10:34:29 fedora thinkfan[733]: WARNING: You're using simple temperature limits without correction values, and your fan will only start at 55 °C. This can be dangerous for your hard drive.                                                                                                                                              
Jul 27 10:34:29 fedora thinkfan[733]: Daemon PID: 741                                                                                                                   
Jul 27 10:34:29 fedora systemd[1]: Started simple and lightweight fan control program.

ls -al /proc/acpi/ibm/fan
-rw-r--r--. 1 root root 0 Jul 27 13:10 /proc/acpi/ibm/fan

[sudhir@fedora ~]$ cat /etc/thinkfan.conf 
######################################################################
# thinkfan 0.7 example config file
# ================================
#
# ATTENTION: There is only very basic sanity checking on the configuration.
# That means you can set your temperature limits as insane as you like. You
# can do anything stupid, e.g. turn off your fan when your CPU reaches 70°C.
#
# That's why this program is called THINKfan: You gotta think for yourself.
#
######################################################################
#
# IBM/Lenovo Thinkpads (thinkpad_acpi, /proc/acpi/ibm)
# ====================================================
#
# IMPORTANT:
#
# To keep your HD from overheating, you have to specify a correction value for
# the sensor that has the HD's temperature. You need to do this because
# thinkfan uses only the highest temperature it can find in the system, and
# that'll most likely never be your HD, as most HDs are already out of spec
# when they reach 55 °C.
# Correction values are applied from left to right in the same order as the
# temperatures are read from the file.
#
# For example:
# tp_thermal /proc/acpi/ibm/thermal (0, 0, 10)
# will add a fixed value of 10 °C the 3rd value read from that file. Check out
# http://www.thinkwiki.org/wiki/Thermal_Sensors to find out how much you may
# want to add to certain temperatures.

#  Syntax:
#  (LEVEL, LOW, HIGH)
#  LEVEL is the fan level to use (0-7 with thinkpad_acpi)
#  LOW is the temperature at which to step down to the previous level
#  HIGH is the temperature at which to step up to the next level
#  All numbers are integers.
#

# I use this on my T61p:
#tp_fan /proc/acpi/ibm/fan
#tp_thermal /proc/acpi/ibm/thermal (0, 10, 15, 2, 10, 5, 0, 3, 0, 3)

hwmon /sys/devices/virtual/hwmon/hwmon0/temp1_input
hwmon /sys/devices/platform/coretemp.0/hwmon/hwmon2/temp3_input
hwmon /sys/devices/platform/coretemp.0/hwmon/hwmon2/temp1_input
hwmon /sys/devices/platform/coretemp.0/hwmon/hwmon2/temp2_input

(0,     0,      55)
(1,     48,     60)
(2,     50,     61)
(3,     52,     63)
(4,     56,     65)
(5,     59,     66)
(7,     63,     32767)


Version-Release number of selected component (if applicable):


How reproducible:


Steps to Reproduce:
1.install thinkfan
2.add sensors find /sys/devices -type f -name "temp*_input"
3.enable and restart

Actual results:


Expected results:


Additional info: