xref: /linux/Documentation/devicetree/bindings/regulator/regulator.txt (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
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-soft-start: Enable soft start so that voltage ramps slowly
28- regulator-state-mem sub-root node for Suspend-to-RAM mode
29  : suspend to memory, the device goes to sleep, but all data stored in memory,
30  only some external interrupt can wake the device.
31- regulator-state-disk sub-root node for Suspend-to-DISK mode
32  : suspend to disk, this state operates similarly to Suspend-to-RAM,
33  but includes a final step of writing memory contents to disk.
34- regulator-state-[mem/disk] node has following common properties:
35	- regulator-on-in-suspend: regulator should be on in suspend state.
36	- regulator-off-in-suspend: regulator should be off in suspend state.
37	- regulator-suspend-microvolt: regulator should be set to this voltage
38	  in suspend.
39	- regulator-mode: operating mode in the given suspend state.
40	  The set of possible operating modes depends on the capabilities of
41	  every hardware so the valid modes are documented on each regulator
42	  device tree binding document.
43- regulator-initial-mode: initial operating mode. The set of possible operating
44  modes depends on the capabilities of every hardware so each device binding
45  documentation explains which values the regulator supports.
46- regulator-system-load: Load in uA present on regulator that is not captured by
47  any consumer request.
48- regulator-pull-down: Enable pull down resistor when the regulator is disabled.
49- regulator-over-current-protection: Enable over current protection.
50- regulator-active-discharge: tristate, enable/disable active discharge of
51  regulators. The values are:
52	0: Disable active discharge.
53	1: Enable active discharge.
54	Absence of this property will leave configuration to default.
55
56Deprecated properties:
57- regulator-compatible: If a regulator chip contains multiple
58  regulators, and if the chip's binding contains a child node that
59  describes each regulator, then this property indicates which regulator
60  this child node is intended to configure. If this property is missing,
61  the node's name will be used instead.
62
63Example:
64
65	xyzreg: regulator@0 {
66		regulator-min-microvolt = <1000000>;
67		regulator-max-microvolt = <2500000>;
68		regulator-always-on;
69		vin-supply = <&vin>;
70
71		regulator-state-mem {
72			regulator-on-in-suspend;
73		};
74	};
75
76Regulator Consumers:
77Consumer nodes can reference one or more of its supplies/
78regulators using the below bindings.
79
80- <name>-supply: phandle to the regulator node
81
82These are the same bindings that a regulator in the above
83example used to reference its own supply, in which case
84its just seen as a special case of a regulator being a
85consumer itself.
86
87Example of a consumer device node (mmc) referencing two
88regulators (twl_reg1 and twl_reg2),
89
90	twl_reg1: regulator@0 {
91		...
92		...
93		...
94	};
95
96	twl_reg2: regulator@1 {
97		...
98		...
99		...
100	};
101
102	mmc: mmc@0x0 {
103		...
104		...
105		vmmc-supply = <&twl_reg1>;
106		vmmcaux-supply = <&twl_reg2>;
107	};
108