1Voltage/Current Regulators
2
3Optional properties:
4- regulator-name: A string used as a descriptive name for regulator outputs
5- regulator-min-microvolt: smallest voltage consumers may set
6- regulator-max-microvolt: largest voltage consumers may set
7- regulator-microvolt-offset: Offset applied to voltages to compensate for voltage drops
8- regulator-min-microamp: smallest current consumers may set
9- regulator-max-microamp: largest current consumers may set
10- regulator-input-current-limit-microamp: maximum input current regulator allows
11- regulator-always-on: boolean, regulator should never be disabled
12- regulator-boot-on: bootloader/firmware enabled regulator
13- regulator-allow-bypass: allow the regulator to go into bypass mode
14- regulator-allow-set-load: allow the regulator performance level to be configured
15- <name>-supply: phandle to the parent supply/regulator node
16- regulator-ramp-delay: ramp delay for regulator(in uV/us)
17  For hardware which supports disabling ramp rate, it should be explicitly
18  initialised to zero (regulator-ramp-delay = <0>) for disabling ramp delay.
19- regulator-enable-ramp-delay: The time taken, in microseconds, for the supply
20  rail to reach the target voltage, plus/minus whatever tolerance the board
21  design requires. This property describes the total system ramp time
22  required due to the combination of internal ramping of the regulator itself,
23  and board design issues such as trace capacitance and load on the supply.
24- regulator-settling-time-us: Settling time, in microseconds, for voltage
25  change if regulator have the constant time for any level voltage change.
26  This is useful when regulator have exponential voltage change.
27- regulator-settling-time-up-us: Settling time, in microseconds, for voltage
28  increase if the regulator needs a constant time to settle after voltage
29  increases of any level. This is useful for regulators with exponential
30  voltage changes.
31- regulator-settling-time-down-us: Settling time, in microseconds, for voltage
32  decrease if the regulator needs a constant time to settle after voltage
33  decreases of any level. This is useful for regulators with exponential
34  voltage changes.
35- regulator-soft-start: Enable soft start so that voltage ramps slowly
36- regulator-state-standby sub-root node for Standby mode
37  : equivalent with standby Linux sleep state, which provides energy savings
38  with a relatively quick transition back time.
39- regulator-state-mem sub-root node for Suspend-to-RAM mode
40  : suspend to memory, the device goes to sleep, but all data stored in memory,
41  only some external interrupt can wake the device.
42- regulator-state-disk sub-root node for Suspend-to-DISK mode
43  : suspend to disk, this state operates similarly to Suspend-to-RAM,
44  but includes a final step of writing memory contents to disk.
45- regulator-state-[mem/disk/standby] node has following common properties:
46	- regulator-on-in-suspend: regulator should be on in suspend state.
47	- regulator-off-in-suspend: regulator should be off in suspend state.
48	- regulator-suspend-min-microvolt: minimum voltage may be set in
49	  suspend state.
50	- regulator-suspend-max-microvolt: maximum voltage may be set in
51	  suspend state.
52	- regulator-suspend-microvolt: the default voltage which regulator
53	  would be set in suspend. This property is now deprecated, instead
54	  setting voltage for suspend mode via the API which regulator
55	  driver provides is recommended.
56	- regulator-changeable-in-suspend: whether the default voltage and
57	  the regulator on/off in suspend can be changed in runtime.
58	- regulator-mode: operating mode in the given suspend state.
59	  The set of possible operating modes depends on the capabilities of
60	  every hardware so the valid modes are documented on each regulator
61	  device tree binding document.
62- regulator-initial-mode: initial operating mode. The set of possible operating
63  modes depends on the capabilities of every hardware so each device binding
64  documentation explains which values the regulator supports.
65- regulator-allowed-modes: list of operating modes that software is allowed to
66  configure for the regulator at run-time.  Elements may be specified in any
67  order.  The set of possible operating modes depends on the capabilities of
68  every hardware so each device binding document explains which values the
69  regulator supports.
70- regulator-system-load: Load in uA present on regulator that is not captured by
71  any consumer request.
72- regulator-pull-down: Enable pull down resistor when the regulator is disabled.
73- regulator-over-current-protection: Enable over current protection.
74- regulator-active-discharge: tristate, enable/disable active discharge of
75  regulators. The values are:
76	0: Disable active discharge.
77	1: Enable active discharge.
78	Absence of this property will leave configuration to default.
79- regulator-coupled-with: Regulators with which the regulator
80  is coupled. The linkage is 2-way - all coupled regulators should be linked
81  with each other. A regulator should not be coupled with its supplier.
82- regulator-coupled-max-spread: Array of maximum spread between voltages of
83  coupled regulators in microvolts, each value in the array relates to the
84  corresponding couple specified by the regulator-coupled-with property.
85- regulator-max-step-microvolt: Maximum difference between current and target
86  voltages that can be changed safely in a single step.
87
88Deprecated properties:
89- regulator-compatible: If a regulator chip contains multiple
90  regulators, and if the chip's binding contains a child node that
91  describes each regulator, then this property indicates which regulator
92  this child node is intended to configure. If this property is missing,
93  the node's name will be used instead.
94
95Example:
96
97	xyzreg: regulator@0 {
98		regulator-min-microvolt = <1000000>;
99		regulator-max-microvolt = <2500000>;
100		regulator-always-on;
101		vin-supply = <&vin>;
102
103		regulator-state-mem {
104			regulator-on-in-suspend;
105		};
106	};
107
108Regulator Consumers:
109Consumer nodes can reference one or more of its supplies/
110regulators using the below bindings.
111
112- <name>-supply: phandle to the regulator node
113
114These are the same bindings that a regulator in the above
115example used to reference its own supply, in which case
116its just seen as a special case of a regulator being a
117consumer itself.
118
119Example of a consumer device node (mmc) referencing two
120regulators (twl_reg1 and twl_reg2),
121
122	twl_reg1: regulator@0 {
123		...
124		...
125		...
126	};
127
128	twl_reg2: regulator@1 {
129		...
130		...
131		...
132	};
133
134	mmc: mmc@0 {
135		...
136		...
137		vmmc-supply = <&twl_reg1>;
138		vmmcaux-supply = <&twl_reg2>;
139	};
140