ACPI
From blag.wiki.aktivix.org
INTRO
I've always been happy with Advanced Power Management bios, (APM), as far as power management is concered. It's simple, there's nothing to configure and I as a regular user can forget all about it. The screen blanks when the laptops' been idle or when the lid's closed. I run `/usr/bin/apm` as a regular user to get an idea of the battery's power status. What's more, all of APM's features work out of the box. Those are the kind of tools that I like sometimes. I don't need to know how or why it works, it just does what I tell it to do.
However, having recently upgraded my kernel to 2.6.14, I decided to try out Advanced Configuration and Power Interface (ACPI). The advantage of ACPI is that one can controll power events via the OS. Previously all APM power events where controlled by the BIOS and the OS had no idea when APM would kick in or what it would do. I set aside some time to try things out as a ****regular user**** to see what all the fuss is about. There are loads of command that root can use but I felt that I'd better use my ordinary account as the potentional for causing havoc is greatly reduced. In order to have a resonably safe and hassle-free time, I've used the following documentaion in /usr/src/linux-2.6.14/Documentation/ibm-acpi.txt (ibm-acpi.txt, from hereon), which describes most of the features of this power management system. Note that ibm-acpi.txt also refers to http://ibm-acpi.sf.net/ and one may look at look at the latter doc for the latest news, as well as a compatability matrix.
See any mistakes? Correct them!
/proc/acpi
This is the top - level diretory.Note that these files seem empty. One uses `cat` as a regular user to use them as commands.
jayeola@00:07:01$ cd /proc/acpi/ && l && file * ac_adapter button event ibm processor wakeup alarm dsdt fadt info thermal_zone battery embedded_controller fan power_resource video ac_adapter: directory alarm: empty battery: directory button: directory dsdt: empty embedded_controller: directory event: empty fadt: empty fan: directory ibm: directory info: empty power_resource: directory processor: directory thermal_zone: directory video: directory wakeup: empty
From here on we will try to run as many commands as possible as a regular user. We are sure not to do any damage this way.
jayeola@00:08:06$ cat /proc/acpi/alarm 2005-11-00 19:00:49
jayeola@00:08:11$ cat /proc/acpi/dsdt cat: dsdt: Permission denied
jayeola@00:09:00$ cat /proc/acpi/info version: 20050902
jayeola@00:09:08$ cat /proc/acpi/wakeup Device Sleep state Status LID 3 * enabled SLPB 3 * enabled PCI0 4 disabled USB 1 disabled UART 3 disabled
proc/acpi/ac_adapter
This appears to be the ac power for the Thinkpad
jayeola@00:10:51$ cat /proc/acpi/ac_adapter/AC/state state: on-line
Battery -- /proc/acpi/battery
jayeola@20:31:13$ cat /proc/acpi/battery/BAT0/state present: yes capacity state: ok charging state: charging present rate: 24140 mW remaining capacity: 2448 mWh present voltage: 11730 mV
jayeola@20:31:29$ cat /proc/acpi/battery/BAT0/info present: yes design capacity: 38880 mWh last full capacity: 23840 mWh battery technology: rechargeable design voltage: 10800 mV design capacity warning: 1944 mWh design capacity low: 388 mWh capacity granularity 1: 1 mWh capacity granularity 2: 1 mWh model number: ThinkPad Battery serial number: battery type: LION OEM info: IBM Corporation
jayeola@20:32:52$ cat /proc/acpi/battery/BAT0/alarm alarm: 1944 mWh
/proc/acpi/button
jayeola@00:11:33$ cat /proc/acpi/button/lid/LID/info type: Lid Switch
jayeola@00:11:49$ cat /proc/acpi/button/lid/LID/state state: open
jayeola@00:12:15$ cat /proc/acpi/button/power/PWRF/info type: Power Button (FF)
jayeola@00:13:10$ cat /proc/acpi/button/sleep/SLPB/info type: Sleep Button (CM)
jayeola@00:13:58$ cat /proc/acpi/embedded_controller/EC/info gpe bit: 0x09 ports: 0x66, 0x62 use global lock: yes
/proc/acpi/ibm/
jayeola@00:15:14$ l -R /proc/acpi/ibm/ ibm/: bay beep bluetooth cmos dock driver hotkey led light thermal video
These are the available commands. test if they work for a regular user below
What driver version am I using? This command has no other options.
jayeola@00:17:44$ cat driver driver: IBM ThinkPad ACPI Extras version: 0.12a
jayeola@19:23:02$ dmesg | grep acpi ibm_acpi: IBM ThinkPad ACPI Extras v0.12a ibm_acpi: http://ibm-acpi.sf.net/ ibm_acpi: dock device not present Registering sys device 'acpi0' ACPI: Please implement acpi_video_bus_ROM_seq_show
Note that `dmesg | grep -i acpi` shows a lot more lines, but I only wanted to know the version in this instance.
UltraBay eject -- /proc/acpi/ibm/bay
jayeola@00:16:38$ cat /proc/acpi/ibm/bay status: occupied commands: eject
I do not have a dosking device. this command is run just to see it's output
ACPI sounds -- /proc/acpi/ibm/beep
jayeola@00:16:19$ cat /proc/acpi/ibm/beep status: supported commands: <cmd> (<cmd> is 0-17)
Use `echo <number> >/proc/acpi/ibm/beep` as root to send commands to the beep device. A good one to try is
for i in {0..20}; do echo $i > /proc/acpi/ibm/beep ; sleep 2; done
Which will loop through all of the beep sounds
Bluetooth -- /proc/acpi/ibm/bluetooth
jayeola@00:16:43$ cat /proc/acpi/ibm/bluetooth status: not supported
There is no built-in bluetooth device. I do have a bluetooth dongle, which works
CMOS control -- /proc/acpi/ibm/cmos
jayeola@00:17:05$ cat /proc/acpi/ibm/cmos status: not supported
Docking / undocking -- /proc/acpi/ibm/dock
jayeola@00:17:39$ cat /proc/acpi/ibm/dock status: undocked
jayeola@00:17:44$ cat /proc/acpi/ibm/driver driver: IBM ThinkPad ACPI Extras version: 0.12a
For driver name and version only. no other commands can be sent to thos file
jayeola@00:17:57$ cat /proc/acpi/ibm/hotkey status: disabled mask: not supported status: disabled mask: not supported commands: enable, disable, reset
Hot keys -- /proc/acpi/ibm/hotkey
root@03:11:14# echo enable > /proc/acpi/ibm/hotkey root@03:11:21# cat /proc/acpi/ibm/hotkey status: enabled mask: not supported commands: enable, disable, reset
Use disable or reset to disable it again
So far when I used this command to enable all of the possible hot keys...
echo 0xffff > /proc/acpi/ibm/hotkey acpi_listen showed only one event for the hotkeys pressed button/sleep SLPB 00000080 00000002
which where the <fn><f4> keys.
actions button/lid LID 00000080 00000001 button/lid LID 00000080 00000002
LED control -- /proc/acpi/ibm/led
jayeola@00:18:24$ cat /proc/acpi/ibm/led status: supported commands: <led> on, <led> off, <led> blink (<led> is 0-7)
The led refers to the light on thinkpad docking stations. which I do not have
ThinkLight control -- /proc/acpi/ibm/light
jayeola@00:18:28$ cat /proc/acpi/ibm/light status: on commands: on, off
Turns the think light built into the lid on and off. The same is acheived by pressing <fn><page up>
Temperature sensors -- /proc/acpi/ibm/thermal
jayeola@00:18:49$ cat /proc/acpi/ibm/thermal temperatures: 49 -128 -128 -128 50 45 -128 -128
There appears to be eight seperate tempature sensors shown here. Acccording to ibm-acpt.txt you'll only be able to access them using ACPI commands. I think this means that not all of them are available, either to the regular user or noobs like me. Also the doc lists the physical location of the sensors in a Thinkpad as observed by Thomas Gruber for his R51:- 1: CPU 2: Mini PCI Module 3: HDD 4: GPU 5: Battery 6: N/A 7: Battery 8: N/A Commands available:- none
Video output control -- /proc/acpi/ibm/video
jayeola@00:18:53$ cat /proc/acpi/ibm/video status: supported lcd: enabled crt: disabled dvi: disabled auto: enabled commands: lcd_enable, lcd_disable commands: crt_enable, crt_disable commands: dvi_enable, dvi_disable commands: auto_enable, auto_disable commands: video_switch, expand_toggle
These commands are for the video modes. Not experimenting here.... chickened out ;-)
/proc/acpi/power_resource/PSER/state
jayeola@00:19:57$ cat /proc/acpi/power_resource/PSER/state state: off system level: S0 order: 0 reference count: 0
jayeola@00:20:27$ cat /proc/acpi/power_resource/PSIO/state state: on system level: S0 order: 0 reference count: 0
/proc/acpi/processor/CPU/
jayeola@00:21:05$ l /proc/acpi/processor/CPU/ info limit power throttling
jayeola@00:21:36$ cat /proc/acpi/processor/CPU/info processor id: 0 acpi id: 1 bus mastering control: yes power management: yes throttling control: yes limit interface: yes
jayeola@00:21:51$ cat /proc/acpi/processor/CPU/limit active limit: P0:T0 user limit: P0:T0 thermal limit: P0:T0
jayeola@00:22:15$ cat /proc/acpi/processor/CPU/power active state: C3 max_cstate: C8 bus master activity: 00000000 states: C1: type[C1] promotion[C2] demotion[--] latency[000] usage[00083320] C2: type[C2] promotion[C3] demotion[C1] latency[001] usage[00086489] *C3: type[C3] promotion[--] demotion[C2] latency[065] usage[04195414]
jayeola@00:22:39$ cat /proc/acpi/processor/CPU/throttling state count: 8 active state: T0 states: *T0: 00% T1: 12% T2: 25% T3: 37% T4: 50% T5: 62% T6: 75% T7: 87%
/proc/acpi/thermal_zone/
jayeola@00:23:19$ l -R /proc/acpi/thermal_zone/ thermal_zone/: THM0
thermal_zone/THM0: cooling_mode polling_frequency state temperature trip_points
jayeola@00:24:12$ cat /proc/acpi/thermal_zone/cooling_mode <setting not supported> cooling mode: passive
jayeola@00:24:15$ cat /proc/acpi/thermal_zone/polling_frequency <polling disabled>
jayeola@00:24:32$ cat /proc/acpi/thermal_zone/state state: ok
jayeola@00:24:51$ cat /proc/acpi/thermal_zone/temperature temperature: 50 C
jayeola@00:25:00$ cat /proc/acpi/thermal_zone/trip_points critical (S5): 97 C passive: 92 C: tc1=5 tc2=3 tsp=600 devices=0xd7fed820
Possibly an upper temperature beyond which the machine is switched off?
/proc/acpi/video/
jayeola@00:26:02$ l -R /proc/acpi/video/ video/: VID
video/VID: CRT0 DOS info LCD0 POST POST_info ROM TV0
video/VID/CRT0: brightness EDID info state
video/VID/LCD0: brightness EDID info state
video/VID/TV0: brightness EDID info state
jayeola@00:27:20$ cat /proc/acpi/video/VID/DOS DOS setting: <1>
jayeola@00:28:12$ cat /proc/acpi/video/VID/info Switching heads: yes Video ROM: no Device to be POSTed on boot: no
jayeola@00:28:31$ cat /proc/acpi/video/VID/POST <not supported>
jayeola@00:28:54$ cat /proc/acpi/video/VID/POST_info <not supported>
jayeola@00:28:59$ cat /proc/acpi/video/VID/ROM <TODO>
jayeola@00:29:22$ cat /proc/acpi/video/VID/CRT0/ brightness EDID info state
jayeola@00:29:22$ cat /proc/acpi/video/VID/CRT0/brightness <not supported>
jayeola@00:29:43$ cat /proc/acpi/video/VID/CRT0/EDID #nothing happens
jayeola@00:29:52$ cat /proc/acpi/video/VID/CRT0/info device_id: 0x0100 type: CRT known by bios: no
jayeola@00:29:57$ cat /proc/acpi/video/VID/CRT0/state state: 0x0d query: 0x00
jayeola@00:30:02$ cat /proc/acpi/video/VID/LCD0/info device_id: 0x0110 type: UNKNOWN known by bios: no jayeola@00:31:00$ cat /proc/acpi/video/VID/LCD0/brightness <not supported>
jayeola@00:31:49$ cat /proc/acpi/video/VID/TV0/ brightness EDID info state
jayeola@00:31:49$ cat /proc/acpi/video/VID/TV0/brightness <not supported> jayeola@00:32:16$ cat /proc/acpi/video/VID/TV0/info device_id: 0x0200 type: TVOUT known by bios: no
jayeola@00:32:27$ cat /proc/acpi/video/VID/TV0/state state: 0x1d query: 0x00
