I am using Ubuntu 13.04 32-bit for quite some time on Acer Aspire One AOD255 netbook and today I found out that power indicator icon is missing from unity panel. Also, I didnot get any low power notification and my laptop just turned off instead of hibernating. The indicator is being displayed on login screen.

upower output:

ali@ali-AOD255:~$ upower -d

Device: /org/freedesktop/UPower/devices/line_power_AC

  native-path:          /sys/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:01/ACPI0003:00/power_supply/AC

  power supply:         yes

  updated:              Sun Jul 21 20:26:31 2013 (773 seconds ago)

  has history:          no

  has statistics:       no

  line-power

    online:             no



Device: /org/freedesktop/UPower/devices/battery_BAT0

  native-path:          /sys/devices/LNXSYSTM:00/LNXSYBUS:00/PNP0A08:00/device:01/PNP0C0A:00/power_supply/BAT0

  vendor:               SANYO

  model:                AL10A31

  power supply:         yes

  updated:              Sun Jul 21 20:39:02 2013 (22 seconds ago)

  has history:          yes

  has statistics:       yes

  battery

    present:             yes

    rechargeable:        yes

    state:               discharging

    energy:              2.9082 Wh

    energy-empty:        0 Wh

    energy-full:         18.1263 Wh

    energy-full-design:  24.42 Wh

    energy-rate:         9.8568 W

    voltage:             10.802 V

    time to empty:       17.7 minutes

    percentage:          16.0441%

    capacity:            74.2273%

    technology:          lithium-ion

  History (charge):

    1374421111  16.044  discharging

  History (rate):

    1374421142  9.857   discharging

    1374421111  9.446   discharging

    1374421080  9.291   discharging



Daemon:

  daemon-version:  0.9.20

  can-suspend:     yes

  can-hibernate:   yes

  on-battery:      yes

  on-low-battery:  no

  lid-is-closed:   no

  lid-is-present:  yes

  is-docked:       no

dmesg output:

ali@ali-AOD255:~$ dmesg | grep -i acpi

[    0.000000] BIOS-e820: [mem 0x000000007f577000-0x000000007f5befff] ACPI NVS

[    0.000000] BIOS-e820: [mem 0x000000007f5ec000-0x000000007f5fefff] ACPI data

[    0.000000] ACPI: RSDP 000fe020 00024 (v02 ACRSYS)

[    0.000000] ACPI: XSDT 7f5fe120 00064 (v01 ACRSYS ACRPRDCT 00000001      01000013)

[    0.000000] ACPI: FACP 7f5fd000 000F4 (v04 ACRSYS ACRPRDCT 00000001 1025 01000013)

[    0.000000] ACPI: DSDT 7f5f1000 08D6F (v01 ACRSYS ACRPRDCT 00000001 1025 01000013)

[    0.000000] ACPI: FACS 7f584000 00040

[    0.000000] ACPI: HPET 7f5fc000 00038 (v01 ACRSYS ACRPRDCT 00000001 1025 01000013)

[    0.000000] ACPI: APIC 7f5fb000 00078 (v02 ACRSYS ACRPRDCT 00000001 1025 01000013)

[    0.000000] ACPI: MCFG 7f5fa000 0003C (v01 ACRSYS ACRPRDCT 00000001 1025 01000013)

[    0.000000] ACPI: SLIC 7f5f0000 00176 (v01 ACRSYS ACRPRDCT 00000001 1025 01000013)

[    0.000000] ACPI: BOOT 7f5ef000 00028 (v01 ACRSYS ACRPRDCT 00000001 1025 01000013)

[    0.000000] ACPI: SSDT 7f5ed000 00655 (v01  PmRef    CpuPm 00003000 INTL 20051117)

[    0.000000] ACPI: WDAT 7f5ec000 00194 (v01 INSYDE INSYDE   00000001 MSFT 01000013)

[    0.000000] ACPI: Local APIC address 0xfee00000

[    0.000000] ACPI: PM-Timer IO Port: 0x408

[    0.000000] ACPI: Local APIC address 0xfee00000

[    0.000000] ACPI: LAPIC (acpi_id[0x01] lapic_id[0x00] enabled)

[    0.000000] ACPI: LAPIC (acpi_id[0x02] lapic_id[0x01] enabled)

[    0.000000] ACPI: LAPIC (acpi_id[0x03] lapic_id[0x00] disabled)

[    0.000000] ACPI: LAPIC (acpi_id[0x04] lapic_id[0x00] disabled)

[    0.000000] ACPI: LAPIC_NMI (acpi_id[0x01] dfl dfl lint[0x1])

[    0.000000] ACPI: LAPIC_NMI (acpi_id[0x02] dfl dfl lint[0x1])

[    0.000000] ACPI: IOAPIC (id[0x04] address[0xfec00000] gsi_base[0])

[    0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 0 global_irq 2 dfl dfl)

[    0.000000] ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 high level)

[    0.000000] ACPI: IRQ0 used by override.

[    0.000000] ACPI: IRQ2 used by override.

[    0.000000] ACPI: IRQ9 used by override.

[    0.000000] Using ACPI (MADT) for SMP configuration information

[    0.000000] ACPI: HPET id: 0x8086a201 base: 0xfed00000

[    0.012225] ACPI: Core revision 20121018

[    0.108314] PM: Registering ACPI NVS region [mem 0x7f577000-0x7f5befff] (294912 bytes)

[    0.111405] ACPI: bus type pci registered

[    0.114917] ACPI: Added _OSI(Module Device)

[    0.114917] ACPI: Added _OSI(Processor Device)

[    0.114917] ACPI: Added _OSI(3.0 _SCP Extensions)

[    0.114917] ACPI: Added _OSI(Processor Aggregator Device)

[    0.119212] ACPI: EC: Look up EC in DSDT

[    0.123126] ACPI: Executed 1 blocks of module-level executable AML code

[    0.127354] [Firmware Bug]: ACPI: BIOS _OSI(Linux) query ignored

[    0.128403] ACPI: SSDT 7f4b7790 00708 (v01  PmRef  Cpu0Ist 00003000 INTL 20051117)

[    0.129765] ACPI: Dynamic OEM Table Load:

[    0.129772] ACPI: SSDT   (null) 00708 (v01  PmRef  Cpu0Ist 00003000 INTL 20051117)

[    0.130144] ACPI: SSDT 7f4b5690 00646 (v01  PmRef  Cpu0Cst 00003001 INTL 20051117)

[    0.131056] ACPI: Dynamic OEM Table Load:

[    0.131063] ACPI: SSDT   (null) 00646 (v01  PmRef  Cpu0Cst 00003001 INTL 20051117)

[    0.131111] ACPI: SSDT 7f4b6d90 0015F (v01  PmRef    ApIst 00003000 INTL 20051117)

[    0.132907] ACPI: Dynamic OEM Table Load:

[    0.132915] ACPI: SSDT   (null) 0015F (v01  PmRef    ApIst 00003000 INTL 20051117)

[    0.132945] ACPI: SSDT 7f4b6f10 0008D (v01  PmRef    ApCst 00003000 INTL 20051117)

[    0.133181] ACPI: Dynamic OEM Table Load:

[    0.133187] ACPI: SSDT   (null) 0008D (v01  PmRef    ApCst 00003000 INTL 20051117)

[    0.133218] ACPI: Interpreter enabled

[    0.133218] ACPI: (supports S0 S3 S4 S5)

[    0.133218] ACPI: Using IOAPIC for interrupt routing

[    0.271632] ACPI: Power Resource [FN00] (on)

[    0.272548] ACPI: EC: GPE = 0x19, I/O: command/status = 0x66, data = 0x62

[    0.272873] ACPI: No dock devices found.

[    0.272885] PCI: Using host bridge windows from ACPI; if necessary, use "pci=nocrs" and report a bug

[    0.273675] ACPI: PCI Root Bridge [PCI0] (domain 0000 [bus 00-ff])

[    0.273683] ACPI: PCI Interrupt Routing Table [_SB_.PCI0._PRT]

[    0.289605] ACPI: PCI Interrupt Routing Table [_SB_.PCI0.EXP1._PRT]

[    0.289745] ACPI: PCI Interrupt Routing Table [_SB_.PCI0.EXP2._PRT]

[    0.290078]  pci0000:00: Requesting ACPI _OSC control (0x1d)

[    0.290538]  pci0000:00: ACPI _OSC control (0x1c) granted

[    0.292537] ACPI: PCI Interrupt Link [LNKA] (IRQs 3 4 5 7 9 10 *11 12)

[    0.292688] ACPI: PCI Interrupt Link [LNKB] (IRQs 3 4 5 7 9 *10 11 12)

[    0.292833] ACPI: PCI Interrupt Link [LNKC] (IRQs 3 4 5 7 9 10 *11 12)

[    0.292978] ACPI: PCI Interrupt Link [LNKD] (IRQs 3 4 5 7 9 10 *11 12)

[    0.293123] ACPI: PCI Interrupt Link [LNKE] (IRQs 3 4 5 7 9 10 11 12) *0, disabled.

[    0.293269] ACPI: PCI Interrupt Link [LNKF] (IRQs 3 4 5 7 9 10 11 12) *0, disabled.

[    0.293415] ACPI: PCI Interrupt Link [LNKG] (IRQs 3 4 5 7 9 10 11 12) *0, disabled.

[    0.293572] ACPI: PCI Interrupt Link [LNKH] (IRQs 3 4 5 7 9 10 11 12) *0, disabled.

[    0.296717] ACPI: bus type scsi registered

[    0.296747] ACPI: bus type usb registered

[    0.296747] PCI: Using ACPI for IRQ routing

[    0.322754] pnp: PnP ACPI init

[    0.322786] ACPI: bus type pnp registered

[    0.384628] system 00:00: Plug and Play ACPI device, IDs PNP0c02 (active)

[    0.384712] pnp 00:01: Plug and Play ACPI device, IDs PNP0200 (active)

[    0.384819] pnp 00:02: Plug and Play ACPI device, IDs PNP0b00 (active)

[    0.385054] pnp 00:03: Plug and Play ACPI device, IDs PNP0103 (active)

[    0.385140] pnp 00:04: Plug and Play ACPI device, IDs PNP0c04 (active)

[    0.385215] pnp 00:05: Plug and Play ACPI device, IDs INT0800 (active)

[    0.385352] pnp 00:06: Plug and Play ACPI device, IDs PNP0303 (active)

[    0.385522] pnp 00:07: Plug and Play ACPI device, IDs SYN1b1c SYN1b00 SYN0002 PNP0f13 (active)

[    0.385863] pnp: PnP ACPI: found 8 devices

[    0.385869] ACPI: ACPI bus type pnp unregistered

[    0.385876] PnPBIOS: Disabled by ACPI PNP

[    1.272199] ACPI: AC Adapter [AC] (off-line)

[    1.272363] ACPI: Power Button [PWRB]

[    1.272469] ACPI: Sleep Button [SLPB]

[    1.272616] ACPI: Lid Switch [LID0]

[    1.272735] ACPI: Power Button [PWRF]

[    1.272854] ACPI: Fan [FAN] (on)

[    1.272990] ACPI: Requesting acpi_cpufreq

[    1.408392] ACPI: Thermal Zone [THRM] (59 C)

[    2.068247] ACPI: Battery Slot [BAT0] (battery present)

[   26.088969] acer_wmi: Acer Laptop ACPI-WMI Extras

[   26.089283] acer_wmi: Brightness must be controlled by acpi video driver

[   26.787802] ACPI Warning: 0x00000428-0x0000042f SystemIO conflicts with Region PMBA 1 (20121018/utaddress-251)

[   26.787822] ACPI: If an ACPI driver is available for this device, you should use it instead of the native driver

[   26.787832] ACPI Warning: 0x00000530-0x0000053f SystemIO conflicts with Region GPIO 1 (20121018/utaddress-251)

[   26.787845] ACPI: If an ACPI driver is available for this device, you should use it instead of the native driver

[   26.787851] ACPI Warning: 0x00000500-0x0000052f SystemIO conflicts with Region GPIO 1 (20121018/utaddress-251)

[   26.787864] ACPI: If an ACPI driver is available for this device, you should use it instead of the native driver

[   28.855074] acpi device:27: registered as cooling_device3

[   28.855507] ACPI: Video Device [OVGA] (multi-head: yes  rom: no  post: no)