xref: /OK3568_Linux_fs/kernel/Documentation/devicetree/bindings/regulator/vctrl.txt (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593SmuzhiyunBindings for Voltage controlled regulators
2*4882a593Smuzhiyun==========================================
3*4882a593Smuzhiyun
4*4882a593SmuzhiyunRequired properties:
5*4882a593Smuzhiyun--------------------
6*4882a593Smuzhiyun- compatible		  : must be "vctrl-regulator".
7*4882a593Smuzhiyun- regulator-min-microvolt : smallest voltage consumers may set
8*4882a593Smuzhiyun- regulator-max-microvolt : largest voltage consumers may set
9*4882a593Smuzhiyun- ctrl-supply		  : The regulator supplying the control voltage.
10*4882a593Smuzhiyun- ctrl-voltage-range	  : an array of two integer values describing the range
11*4882a593Smuzhiyun			    (min/max) of the control voltage. The values specify
12*4882a593Smuzhiyun			    the control voltage needed to generate the corresponding
13*4882a593Smuzhiyun			    regulator-min/max-microvolt output voltage.
14*4882a593Smuzhiyun
15*4882a593SmuzhiyunOptional properties:
16*4882a593Smuzhiyun--------------------
17*4882a593Smuzhiyun- ovp-threshold-percent	: overvoltage protection (OVP) threshold of the
18*4882a593Smuzhiyun			  regulator in percent. Some regulators have an OVP
19*4882a593Smuzhiyun			  circuitry which shuts down the regulator when the
20*4882a593Smuzhiyun			  actual output voltage deviates beyond a certain
21*4882a593Smuzhiyun			  margin from the expected value for a given control
22*4882a593Smuzhiyun			  voltage. On larger voltage decreases this can occur
23*4882a593Smuzhiyun			  undesiredly since the output voltage does not adjust
24*4882a593Smuzhiyun			  inmediately to changes in the control voltage. To
25*4882a593Smuzhiyun			  avoid this situation the vctrl driver breaks down
26*4882a593Smuzhiyun			  larger voltage decreases into multiple steps, where
27*4882a593Smuzhiyun			  each step is within the OVP threshold.
28*4882a593Smuzhiyun- min-slew-down-rate	: Describes how slowly the regulator voltage will decay
29*4882a593Smuzhiyun			  down in the worst case (lightest expected load).
30*4882a593Smuzhiyun			  Specified in uV / us (like main regulator ramp rate).
31*4882a593Smuzhiyun			  This value is required when ovp-threshold-percent is
32*4882a593Smuzhiyun			  specified.
33*4882a593Smuzhiyun
34*4882a593SmuzhiyunExample:
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun	vctrl-reg {
37*4882a593Smuzhiyun		compatible = "vctrl-regulator";
38*4882a593Smuzhiyun		regulator-name = "vctrl_reg";
39*4882a593Smuzhiyun
40*4882a593Smuzhiyun		ctrl-supply = <&ctrl_reg>;
41*4882a593Smuzhiyun
42*4882a593Smuzhiyun		regulator-min-microvolt = <800000>;
43*4882a593Smuzhiyun		regulator-max-microvolt = <1500000>;
44*4882a593Smuzhiyun
45*4882a593Smuzhiyun		ctrl-voltage-range = <200000 500000>;
46*4882a593Smuzhiyun
47*4882a593Smuzhiyun		min-slew-down-rate = <225>;
48*4882a593Smuzhiyun		ovp-threshold-percent = <16>;
49*4882a593Smuzhiyun	};
50