1 ACPI Time and Alarm (TAD) device attributes. 2 3What: /sys/bus/platform/devices/ACPI000E:00/caps 4Date: March 2018 5Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 6Description: 7 (RO) Hexadecimal bitmask of the TAD attributes are reported by 8 the platform firmware (see ACPI 6.2, section 9.18.2): 9 10 ======= ====================================================== 11 BIT(0): AC wakeup implemented if set 12 BIT(1): DC wakeup implemented if set 13 BIT(2): Get/set real time features implemented if set 14 BIT(3): Real time accuracy in milliseconds if set 15 BIT(4): Correct status reported for wakeups from S4/S5 if set 16 BIT(5): The AC timer wakes up from S4 if set 17 BIT(6): The AC timer wakes up from S5 if set 18 BIT(7): The DC timer wakes up from S4 if set 19 BIT(8): The DC timer wakes up from S5 if set 20 ======= ====================================================== 21 22 The other bits are reserved. 23 24What: /sys/bus/platform/devices/ACPI000E:00/ac_alarm 25Date: March 2018 26Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 27Description: 28 (RW) The AC alarm timer value. 29 30 Reads return the current AC alarm timer value in seconds or 31 "disabled", if the AC alarm is not set to wake up the system. 32 33 Write a new AC alarm timer value in seconds or "disabled" to it 34 to set the AC alarm timer or to disable it, respectively. 35 36 If the AC alarm timer is set through this attribute and it 37 expires, it will immediately wake up the system from the S3 38 sleep state (and from S4/S5 too if supported) until its status 39 is explicitly cleared via the ac_status attribute. 40 41What: /sys/bus/platform/devices/ACPI000E:00/ac_policy 42Date: March 2018 43Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 44Description: 45 (RW) The AC alarm expired timer wake policy (see ACPI 6.2, 46 Section 9.18 for details). 47 48 Reads return the current expired timer wake delay for the AC 49 alarm timer or "never", if the policy is to discard AC timer 50 wakeups if the system is on DC power. 51 52 Write a new expired timer wake delay for the AC alarm timer in 53 seconds or "never" to it to set the expired timer wake delay for 54 the AC alarm timer or to set its expired wake policy to discard 55 wakeups if the system is on DC power, respectively. 56 57What: /sys/bus/platform/devices/ACPI000E:00/ac_status 58Date: March 2018 59Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 60Description: 61 (RW) The AC alarm status. 62 63 Reads return a hexadecimal bitmask representing the AC alarm 64 timer status with the following meaning of bits (see ACPI 6.2, 65 Section 9.18.5): 66 67 ======= ====================================================== 68 Bit(0): The timer has expired if set. 69 Bit(1): The timer has woken up the system from a sleep state 70 (S3 or S4/S5 if supported) if set. 71 ======= ====================================================== 72 73 The other bits are reserved. 74 75 Reads also cause the AC alarm timer status to be reset. 76 77 Another way to reset the the status of the AC alarm timer is to 78 write (the number) 0 to this file. 79 80 If the status return value indicates that the timer has expired, 81 it will immediately wake up the system from the S3 sleep state 82 (and from S4/S5 too if supported) until its status is explicitly 83 cleared through this attribute. 84 85What: /sys/bus/platform/devices/ACPI000E:00/dc_alarm 86Date: March 2018 87Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 88Description: 89 (RW,optional) The DC alarm timer value. 90 91 This attribute is only present if the TAD supports a separate 92 DC timer. 93 94 It is analogous to the ac_alarm attribute. 95 96What: /sys/bus/platform/devices/ACPI000E:00/dc_policy 97Date: March 2018 98Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 99Description: 100 (RW,optional) The DC alarm expired timer wake policy. 101 102 This attribute is only present if the TAD supports a separate 103 DC timer. 104 105 It is analogous to the ac_policy attribute. 106 107What: /sys/bus/platform/devices/ACPI000E:00/dc_status 108Date: March 2018 109Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 110 111Description: 112 (RW,optional) The DC alarm status. 113 114 This attribute is only present if the TAD supports a separate 115 DC timer. 116 117 It is analogous to the ac_status attribute. 118