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+ ACPI Time and Alarm (TAD) device attributes.
+
+What: /sys/bus/platform/devices/ACPI000E:00/caps
+Date: March 2018
+Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+ (RO) Hexadecimal bitmask of the TAD attributes are reported by
+ the platform firmware (see ACPI 6.2, section 9.18.2):
+
+ ======= ======================================================
+ BIT(0): AC wakeup implemented if set
+ BIT(1): DC wakeup implemented if set
+ BIT(2): Get/set real time features implemented if set
+ BIT(3): Real time accuracy in milliseconds if set
+ BIT(4): Correct status reported for wakeups from S4/S5 if set
+ BIT(5): The AC timer wakes up from S4 if set
+ BIT(6): The AC timer wakes up from S5 if set
+ BIT(7): The DC timer wakes up from S4 if set
+ BIT(8): The DC timer wakes up from S5 if set
+ ======= ======================================================
+
+ The other bits are reserved.
+
+What: /sys/bus/platform/devices/ACPI000E:00/ac_alarm
+Date: March 2018
+Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+ (RW) The AC alarm timer value.
+
+ Reads return the current AC alarm timer value in seconds or
+ "disabled", if the AC alarm is not set to wake up the system.
+
+ Write a new AC alarm timer value in seconds or "disabled" to it
+ to set the AC alarm timer or to disable it, respectively.
+
+ If the AC alarm timer is set through this attribute and it
+ expires, it will immediately wake up the system from the S3
+ sleep state (and from S4/S5 too if supported) until its status
+ is explicitly cleared via the ac_status attribute.
+
+What: /sys/bus/platform/devices/ACPI000E:00/ac_policy
+Date: March 2018
+Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+ (RW) The AC alarm expired timer wake policy (see ACPI 6.2,
+ Section 9.18 for details).
+
+ Reads return the current expired timer wake delay for the AC
+ alarm timer or "never", if the policy is to discard AC timer
+ wakeups if the system is on DC power.
+
+ Write a new expired timer wake delay for the AC alarm timer in
+ seconds or "never" to it to set the expired timer wake delay for
+ the AC alarm timer or to set its expired wake policy to discard
+ wakeups if the system is on DC power, respectively.
+
+What: /sys/bus/platform/devices/ACPI000E:00/ac_status
+Date: March 2018
+Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+ (RW) The AC alarm status.
+
+ Reads return a hexadecimal bitmask representing the AC alarm
+ timer status with the following meaning of bits (see ACPI 6.2,
+ Section 9.18.5):
+
+ ======= ======================================================
+ Bit(0): The timer has expired if set.
+ Bit(1): The timer has woken up the system from a sleep state
+ (S3 or S4/S5 if supported) if set.
+ ======= ======================================================
+
+ The other bits are reserved.
+
+ Reads also cause the AC alarm timer status to be reset.
+
+ Another way to reset the status of the AC alarm timer is to
+ write (the number) 0 to this file.
+
+ If the status return value indicates that the timer has expired,
+ it will immediately wake up the system from the S3 sleep state
+ (and from S4/S5 too if supported) until its status is explicitly
+ cleared through this attribute.
+
+What: /sys/bus/platform/devices/ACPI000E:00/dc_alarm
+Date: March 2018
+Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+ (RW,optional) The DC alarm timer value.
+
+ This attribute is only present if the TAD supports a separate
+ DC timer.
+
+ It is analogous to the ac_alarm attribute.
+
+What: /sys/bus/platform/devices/ACPI000E:00/dc_policy
+Date: March 2018
+Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+Description:
+ (RW,optional) The DC alarm expired timer wake policy.
+
+ This attribute is only present if the TAD supports a separate
+ DC timer.
+
+ It is analogous to the ac_policy attribute.
+
+What: /sys/bus/platform/devices/ACPI000E:00/dc_status
+Date: March 2018
+Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
+
+Description:
+ (RW,optional) The DC alarm status.
+
+ This attribute is only present if the TAD supports a separate
+ DC timer.
+
+ It is analogous to the ac_status attribute.