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