diff options
Diffstat (limited to 'Documentation')
-rw-r--r-- | Documentation/laptops/thinkpad-acpi.txt | 47 |
1 files changed, 41 insertions, 6 deletions
diff --git a/Documentation/laptops/thinkpad-acpi.txt b/Documentation/laptops/thinkpad-acpi.txt index af1f2bcb6f66..73b80a7e9b03 100644 --- a/Documentation/laptops/thinkpad-acpi.txt +++ b/Documentation/laptops/thinkpad-acpi.txt | |||
@@ -876,28 +876,63 @@ The cmos command interface is prone to firmware split-brain problems, as | |||
876 | in newer ThinkPads it is just a compatibility layer. Do not use it, it is | 876 | in newer ThinkPads it is just a compatibility layer. Do not use it, it is |
877 | exported just as a debug tool. | 877 | exported just as a debug tool. |
878 | 878 | ||
879 | LED control -- /proc/acpi/ibm/led | 879 | LED control |
880 | --------------------------------- | 880 | ----------- |
881 | 881 | ||
882 | Some of the LED indicators can be controlled through this feature. The | 882 | procfs: /proc/acpi/ibm/led |
883 | available commands are: | 883 | sysfs attributes: as per led class, see below for names |
884 | |||
885 | Some of the LED indicators can be controlled through this feature. On | ||
886 | some older ThinkPad models, it is possible to query the status of the | ||
887 | LED indicators as well. Newer ThinkPads cannot query the real status | ||
888 | of the LED indicators. | ||
889 | |||
890 | procfs notes: | ||
891 | |||
892 | The available commands are: | ||
884 | 893 | ||
885 | echo '<led number> on' >/proc/acpi/ibm/led | 894 | echo '<led number> on' >/proc/acpi/ibm/led |
886 | echo '<led number> off' >/proc/acpi/ibm/led | 895 | echo '<led number> off' >/proc/acpi/ibm/led |
887 | echo '<led number> blink' >/proc/acpi/ibm/led | 896 | echo '<led number> blink' >/proc/acpi/ibm/led |
888 | 897 | ||
889 | The <led number> range is 0 to 7. The set of LEDs that can be | 898 | The <led number> range is 0 to 7. The set of LEDs that can be |
890 | controlled varies from model to model. Here is the mapping on the X40: | 899 | controlled varies from model to model. Here is the common ThinkPad |
900 | mapping: | ||
891 | 901 | ||
892 | 0 - power | 902 | 0 - power |
893 | 1 - battery (orange) | 903 | 1 - battery (orange) |
894 | 2 - battery (green) | 904 | 2 - battery (green) |
895 | 3 - UltraBase | 905 | 3 - UltraBase/dock |
896 | 4 - UltraBay | 906 | 4 - UltraBay |
907 | 5 - UltraBase battery slot | ||
908 | 6 - (unknown) | ||
897 | 7 - standby | 909 | 7 - standby |
898 | 910 | ||
899 | All of the above can be turned on and off and can be made to blink. | 911 | All of the above can be turned on and off and can be made to blink. |
900 | 912 | ||
913 | sysfs notes: | ||
914 | |||
915 | The ThinkPad LED sysfs interface is described in detail by the led class | ||
916 | documentation, in Documentation/leds-class.txt. | ||
917 | |||
918 | The leds are named (in LED ID order, from 0 to 7): | ||
919 | "tpacpi::power", "tpacpi:orange:batt", "tpacpi:green:batt", | ||
920 | "tpacpi::dock_active", "tpacpi::bay_active", "tpacpi::dock_batt", | ||
921 | "tpacpi::unknown_led", "tpacpi::standby". | ||
922 | |||
923 | Due to limitations in the sysfs led class, if the status of the LED | ||
924 | indicators cannot be read due to an error, thinkpad-acpi will report it as | ||
925 | a brightness of zero (same as LED off). | ||
926 | |||
927 | If the thinkpad firmware doesn't support reading the current status, | ||
928 | trying to read the current LED brightness will just return whatever | ||
929 | brightness was last written to that attribute. | ||
930 | |||
931 | These LEDs can blink using hardware acceleration. To request that a | ||
932 | ThinkPad indicator LED should blink in hardware accelerated mode, use the | ||
933 | "timer" trigger, and leave the delay_on and delay_off parameters set to | ||
934 | zero (to request hardware acceleration autodetection). | ||
935 | |||
901 | ACPI sounds -- /proc/acpi/ibm/beep | 936 | ACPI sounds -- /proc/acpi/ibm/beep |
902 | ---------------------------------- | 937 | ---------------------------------- |
903 | 938 | ||