xref: /OK3568_Linux_fs/kernel/Documentation/ABI/testing/sysfs-devices-platform-ACPI-TAD (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun		ACPI Time and Alarm (TAD) device attributes.
2*4882a593Smuzhiyun
3*4882a593SmuzhiyunWhat:		/sys/bus/platform/devices/ACPI000E:00/caps
4*4882a593SmuzhiyunDate:		March 2018
5*4882a593SmuzhiyunContact:	Rafael J. Wysocki <rafael.j.wysocki@intel.com>
6*4882a593SmuzhiyunDescription:
7*4882a593Smuzhiyun		(RO) Hexadecimal bitmask of the TAD attributes are reported by
8*4882a593Smuzhiyun		the platform firmware (see ACPI 6.2, section 9.18.2):
9*4882a593Smuzhiyun
10*4882a593Smuzhiyun		======= ======================================================
11*4882a593Smuzhiyun		BIT(0): AC wakeup implemented if set
12*4882a593Smuzhiyun		BIT(1): DC wakeup implemented if set
13*4882a593Smuzhiyun		BIT(2): Get/set real time features implemented if set
14*4882a593Smuzhiyun		BIT(3): Real time accuracy in milliseconds if set
15*4882a593Smuzhiyun		BIT(4): Correct status reported for wakeups from S4/S5 if set
16*4882a593Smuzhiyun		BIT(5): The AC timer wakes up from S4 if set
17*4882a593Smuzhiyun		BIT(6): The AC timer wakes up from S5 if set
18*4882a593Smuzhiyun		BIT(7): The DC timer wakes up from S4 if set
19*4882a593Smuzhiyun		BIT(8): The DC timer wakes up from S5 if set
20*4882a593Smuzhiyun		======= ======================================================
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun		The other bits are reserved.
23*4882a593Smuzhiyun
24*4882a593SmuzhiyunWhat:		/sys/bus/platform/devices/ACPI000E:00/ac_alarm
25*4882a593SmuzhiyunDate:		March 2018
26*4882a593SmuzhiyunContact:	Rafael J. Wysocki <rafael.j.wysocki@intel.com>
27*4882a593SmuzhiyunDescription:
28*4882a593Smuzhiyun		(RW) The AC alarm timer value.
29*4882a593Smuzhiyun
30*4882a593Smuzhiyun		Reads return the current AC alarm timer value in seconds or
31*4882a593Smuzhiyun		"disabled", if the AC alarm is not set to wake up the system.
32*4882a593Smuzhiyun
33*4882a593Smuzhiyun		Write a new AC alarm timer value in seconds or "disabled" to it
34*4882a593Smuzhiyun		to set the AC alarm timer or to disable it, respectively.
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun		If the AC alarm timer is set through this attribute and it
37*4882a593Smuzhiyun		expires, it will immediately wake up the system from the S3
38*4882a593Smuzhiyun		sleep state (and from S4/S5 too if supported) until its status
39*4882a593Smuzhiyun		is explicitly cleared via the ac_status attribute.
40*4882a593Smuzhiyun
41*4882a593SmuzhiyunWhat:		/sys/bus/platform/devices/ACPI000E:00/ac_policy
42*4882a593SmuzhiyunDate:		March 2018
43*4882a593SmuzhiyunContact:	Rafael J. Wysocki <rafael.j.wysocki@intel.com>
44*4882a593SmuzhiyunDescription:
45*4882a593Smuzhiyun		(RW) The AC alarm expired timer wake policy (see ACPI 6.2,
46*4882a593Smuzhiyun		Section 9.18 for details).
47*4882a593Smuzhiyun
48*4882a593Smuzhiyun		Reads return the current expired timer wake delay for the AC
49*4882a593Smuzhiyun		alarm timer or "never", if the policy is to discard AC timer
50*4882a593Smuzhiyun		wakeups if the system is on DC power.
51*4882a593Smuzhiyun
52*4882a593Smuzhiyun		Write a new expired timer wake delay for the AC alarm timer in
53*4882a593Smuzhiyun		seconds or "never" to it to set the expired timer wake delay for
54*4882a593Smuzhiyun		the AC alarm timer or to set its expired wake policy to discard
55*4882a593Smuzhiyun		wakeups if the system is on DC power, respectively.
56*4882a593Smuzhiyun
57*4882a593SmuzhiyunWhat:		/sys/bus/platform/devices/ACPI000E:00/ac_status
58*4882a593SmuzhiyunDate:		March 2018
59*4882a593SmuzhiyunContact:	Rafael J. Wysocki <rafael.j.wysocki@intel.com>
60*4882a593SmuzhiyunDescription:
61*4882a593Smuzhiyun		(RW) The AC alarm status.
62*4882a593Smuzhiyun
63*4882a593Smuzhiyun		Reads return a hexadecimal bitmask representing the AC alarm
64*4882a593Smuzhiyun		timer status with the following meaning of bits (see ACPI 6.2,
65*4882a593Smuzhiyun		Section 9.18.5):
66*4882a593Smuzhiyun
67*4882a593Smuzhiyun		======= ======================================================
68*4882a593Smuzhiyun		Bit(0): The timer has expired if set.
69*4882a593Smuzhiyun		Bit(1): The timer has woken up the system from a sleep state
70*4882a593Smuzhiyun		        (S3 or S4/S5 if supported) if set.
71*4882a593Smuzhiyun		======= ======================================================
72*4882a593Smuzhiyun
73*4882a593Smuzhiyun		The other bits are reserved.
74*4882a593Smuzhiyun
75*4882a593Smuzhiyun		Reads also cause the AC alarm timer status to be reset.
76*4882a593Smuzhiyun
77*4882a593Smuzhiyun		Another way to reset the the status of the AC alarm timer is to
78*4882a593Smuzhiyun		write (the number) 0 to this file.
79*4882a593Smuzhiyun
80*4882a593Smuzhiyun		If the status return value indicates that the timer has expired,
81*4882a593Smuzhiyun		it will immediately wake up the system from the S3 sleep state
82*4882a593Smuzhiyun		(and from S4/S5 too if supported) until its status is explicitly
83*4882a593Smuzhiyun		cleared through this attribute.
84*4882a593Smuzhiyun
85*4882a593SmuzhiyunWhat:		/sys/bus/platform/devices/ACPI000E:00/dc_alarm
86*4882a593SmuzhiyunDate:		March 2018
87*4882a593SmuzhiyunContact:	Rafael J. Wysocki <rafael.j.wysocki@intel.com>
88*4882a593SmuzhiyunDescription:
89*4882a593Smuzhiyun		(RW,optional) The DC alarm timer value.
90*4882a593Smuzhiyun
91*4882a593Smuzhiyun		This attribute is only present if the TAD supports a separate
92*4882a593Smuzhiyun		DC timer.
93*4882a593Smuzhiyun
94*4882a593Smuzhiyun		It is analogous to the ac_alarm attribute.
95*4882a593Smuzhiyun
96*4882a593SmuzhiyunWhat:		/sys/bus/platform/devices/ACPI000E:00/dc_policy
97*4882a593SmuzhiyunDate:		March 2018
98*4882a593SmuzhiyunContact:	Rafael J. Wysocki <rafael.j.wysocki@intel.com>
99*4882a593SmuzhiyunDescription:
100*4882a593Smuzhiyun		(RW,optional) The DC alarm expired timer wake policy.
101*4882a593Smuzhiyun
102*4882a593Smuzhiyun		This attribute is only present if the TAD supports a separate
103*4882a593Smuzhiyun		DC timer.
104*4882a593Smuzhiyun
105*4882a593Smuzhiyun		It is analogous to the ac_policy attribute.
106*4882a593Smuzhiyun
107*4882a593SmuzhiyunWhat:		/sys/bus/platform/devices/ACPI000E:00/dc_status
108*4882a593SmuzhiyunDate:		March 2018
109*4882a593SmuzhiyunContact:	Rafael J. Wysocki <rafael.j.wysocki@intel.com>
110*4882a593Smuzhiyun
111*4882a593SmuzhiyunDescription:
112*4882a593Smuzhiyun		(RW,optional) The DC alarm status.
113*4882a593Smuzhiyun
114*4882a593Smuzhiyun		This attribute is only present if the TAD supports a separate
115*4882a593Smuzhiyun		DC timer.
116*4882a593Smuzhiyun
117*4882a593Smuzhiyun		It is analogous to the ac_status attribute.
118