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Wireless networking not working after resume in Ubuntu 14.04

[Update]:
The same problem exists in Kubuntu and is solved in the same manner.
[Solved]:
By applying the following command nmcli nm I got the following:

Before suspend

RUNNING         STATE           WIFI-HARDWARE   WIFI       WWAN-HARDWARE   WWAN      
running         connected       enabled         enabled    enabled         enabled

as can you see the state is connected and the rest are enabled and running

After suspend

RUNNING         STATE           WIFI-HARDWARE   WIFI       WWAN-HARDWARE   WWAN      
running         asleep          enabled         enabled    enabled         disabled

as can you see the state is asleep meaning our dear network manager is still napping, so to solve use the fallowing command line:
sudo nmcli nm sleep false
this tells the network manager to wake the hell up. to make this permenant :
create a script in /etc/pm/sleep.d containg the following (and don't forget to mark the script as executable):

#!/bin/sh

case "${1}" in
        resume|thaw)
        nmcli nm sleep false
                ;;
esac

Thanks to this

The original problem:

I just downloaded Ubuntu 14.04 and installed on my laptop: ASUS X61SL with Intel P8400 Core2Duo x64 processor.
When I close the lid, the system is suspended, but when I open the lid again and resume, the wireless networking is not activited (networking as a whole is disabled), and when I select "Enable Networking" nothing happens.
This is the information about my wireless adapter:

$ lspci | grep -i wireless
02:00.0 Network controller: Qualcomm Atheros AR928X Wireless Network Adapter (PCI-Express) (rev 01)

This problem wasn't present in Ubuntu 13.04, Linux Mint Debian Edition or Debian 7 wheezy (GNOME or KDE).

Edit: few test with the following results :
The problem effects my wireless and wired networking.
Note: I need to add the pci=nomsi line to grub in order to boot.
When logging out manually then suspend then resume then log in every thing works just fine.
When suspending directly while logged in the problem happens.
Locking and suspending causes the same problem as suspending directly.
Also this problem appearnlty affects log out function: if you chose log out from the user menu in unity panel then you wan't log out, but if you use the command line gnome-session-quit --logout then you can log out.
Now with lshw -C network output:
Normal (fully functional networking):

  *-network               
       description: Ethernet interface
       product: 191 Gigabit Ethernet Adapter
       vendor: Silicon Integrated Systems [SiS]
       physical id: 4
       bus info: pci@0000:00:04.0
       logical name: eth0
       version: 02
       serial: 00:24:8c:1e:f8:53
       size: 10Mbit/s
       capacity: 100Mbit/s
       width: 32 bits
       clock: 33MHz
       capabilities: pm bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=sis190 driverversion=1.4 duplex=half latency=0 link=no multicast=yes port=MII speed=10Mbit/s
       resources: irq:19 memory:fddfcc00-fddfcc7f ioport:cc00(size=128)
  *-network
       description: Wireless interface
       product: AR928X Wireless Network Adapter (PCI-Express)
       vendor: Qualcomm Atheros
       physical id: 0
       bus info: pci@0000:02:00.0
       logical name: wlan0
       version: 01
       serial: 00:15:af:e2:13:db
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress msix bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=ath9k driverversion=3.13.0-24-generic firmware=N/A ip=6.6.6.8 latency=0 link=yes multicast=yes wireless=IEEE 802.11bgn
       resources: irq:16 memory:fdff0000-fdffffff

After resume ("/etc/pm/config.d" does not contains "unload_modules"):

 *-network DISABLED      
       description: Ethernet interface
       product: 191 Gigabit Ethernet Adapter
       vendor: Silicon Integrated Systems [SiS]
       physical id: 4
       bus info: pci@0000:00:04.0
       logical name: eth0
       version: 02
       serial: 00:24:8c:1e:f8:53
       size: 10Mbit/s
       capacity: 100Mbit/s
       width: 32 bits
       clock: 33MHz
       capabilities: pm bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=sis190 driverversion=1.4 duplex=half latency=0 link=no multicast=yes port=MII speed=10Mbit/s
       resources: irq:19 memory:fddfcc00-fddfcc7f ioport:cc00(size=128)
  *-network DISABLED
       description: Wireless interface
       product: AR928X Wireless Network Adapter (PCI-Express)
       vendor: Qualcomm Atheros
       physical id: 0
       bus info: pci@0000:02:00.0
       logical name: wlan0
       version: 01
       serial: 00:15:af:e2:13:db
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress msix bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=ath9k driverversion=3.13.0-24-generic firmware=N/A latency=0 link=no multicast=yes wireless=IEEE 802.11bgn
       resources: irq:16 memory:fdff0000-fdffffff

When I added the file unload_modules to directory "/etc/pm/config.d" as suggested by here, after logging out, suspend ,resume then log in the networking works but I cannot connect to my wireless network.
Again the result of lshw -C network After resume ( "/etc/pm/config.d" contains "unload_modules"):

 *-network DISABLED      
       description: Ethernet interface
       product: 191 Gigabit Ethernet Adapter
       vendor: Silicon Integrated Systems [SiS]
       physical id: 4
       bus info: pci@0000:00:04.0
       logical name: eth0
       version: 02
       serial: 00:24:8c:1e:f8:53
       size: 10Mbit/s
       capacity: 100Mbit/s
       width: 32 bits
       clock: 33MHz
       capabilities: pm bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=sis190 driverversion=1.4 duplex=half latency=0 link=no multicast=yes port=MII speed=10Mbit/s
       resources: irq:19 memory:fddfcc00-fddfcc7f ioport:cc00(size=128)
  *-network DISABLED
       description: Wireless interface
       product: AR928X Wireless Network Adapter (PCI-Express)
       vendor: Qualcomm Atheros
       physical id: 0
       bus info: pci@0000:02:00.0
       logical name: wlan0
       version: 01
       serial: 00:15:af:e2:13:db
       width: 64 bits
       clock: 33MHz
       capabilities: pm msi pciexpress msix bus_master cap_list ethernet physical wireless
       configuration: broadcast=yes driver=ath9k driverversion=3.13.0-24-generic firmware=N/A latency=0 link=no multicast=yes wireless=IEEE 802.11bgn
       resources: irq:16 memory:fdff0000-fdffffff

The contents of 'unload_modules" where:

SUSPEND_MODULES="$SUSPEND_MODULES ath9k"
SUSPEND_MODULES="$SUSPEND_MODULES sis190"

Where 'ath9k' is my wireless module and 'sis190' is my Ethernet module.

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