1* Maxim MAX8997 Voltage and Current Regulator
2
3The Maxim MAX8997 is a multi-function device which includes voltage and
4current regulators, rtc, charger controller and other sub-blocks. It is
5interfaced to the host controller using a i2c interface. Each sub-block is
6addressed by the host system using different i2c slave address. This document
7describes the bindings for 'pmic' sub-block of max8997.
8
9Required properties:
10- compatible: Should be "maxim,max8997-pmic".
11- reg: Specifies the i2c slave address of the pmic block. It should be 0x66.
12
13- max8997,pmic-buck1-dvs-voltage: A set of 8 voltage values in micro-volt (uV)
14  units for buck1 when changing voltage using gpio dvs. Refer to [1] below
15  for additional information.
16
17- max8997,pmic-buck2-dvs-voltage: A set of 8 voltage values in micro-volt (uV)
18  units for buck2 when changing voltage using gpio dvs. Refer to [1] below
19  for additional information.
20
21- max8997,pmic-buck5-dvs-voltage: A set of 8 voltage values in micro-volt (uV)
22  units for buck5 when changing voltage using gpio dvs. Refer to [1] below
23  for additional information.
24
25[1] If none of the 'max8997,pmic-buck[1/2/5]-uses-gpio-dvs' optional
26    property is specified, the 'max8997,pmic-buck[1/2/5]-dvs-voltage'
27    property should specify atleast one voltage level (which would be a
28    safe operating voltage).
29
30    If either of the 'max8997,pmic-buck[1/2/5]-uses-gpio-dvs' optional
31    property is specified, then all the eight voltage values for the
32    'max8997,pmic-buck[1/2/5]-dvs-voltage' should be specified.
33
34Optional properties:
35- interrupt-parent: Specifies the phandle of the interrupt controller to which
36  the interrupts from max8997 are delivered to.
37- interrupts: Interrupt specifiers for two interrupt sources.
38  - First interrupt specifier is for 'irq1' interrupt.
39  - Second interrupt specifier is for 'alert' interrupt.
40- max8997,pmic-buck1-uses-gpio-dvs: 'buck1' can be controlled by gpio dvs.
41- max8997,pmic-buck2-uses-gpio-dvs: 'buck2' can be controlled by gpio dvs.
42- max8997,pmic-buck5-uses-gpio-dvs: 'buck5' can be controlled by gpio dvs.
43
44Additional properties required if either of the optional properties are used:
45- max8997,pmic-ignore-gpiodvs-side-effect: When GPIO-DVS mode is used for
46  multiple bucks, changing the voltage value of one of the bucks may affect
47  that of another buck, which is the side effect of the change (set_voltage).
48  Use this property to ignore such side effects and change the voltage.
49
50- max8997,pmic-buck125-default-dvs-idx: Default voltage setting selected from
51  the possible 8 options selectable by the dvs gpios. The value of this
52  property should be between 0 and 7. If not specified or if out of range, the
53  default value of this property is set to 0.
54
55- max8997,pmic-buck125-dvs-gpios: GPIO specifiers for three host gpio's used
56  for dvs. The format of the gpio specifier depends in the gpio controller.
57
58Regulators: The regulators of max8997 that have to be instantiated should be
59included in a sub-node named 'regulators'. Regulator nodes included in this
60sub-node should be of the format as listed below.
61
62	regulator_name {
63		standard regulator bindings here
64	};
65
66The following are the names of the regulators that the max8997 pmic block
67supports. Note: The 'n' in LDOn and BUCKn represents the LDO or BUCK number
68as per the datasheet of max8997.
69
70	- LDOn
71		  - valid values for n are 1 to 18 and 21
72		  - Example: LDO0, LD01, LDO2, LDO21
73	- BUCKn
74		  - valid values for n are 1 to 7.
75		  - Example: BUCK1, BUCK2, BUCK3, BUCK7
76
77	- ENVICHG: Battery Charging Current Monitor Output. This is a fixed
78		   voltage type regulator
79
80	- ESAFEOUT1: (ldo19)
81	- ESAFEOUT2: (ld020)
82
83	- CHARGER_CV: main battery charger voltage control
84	- CHARGER: main battery charger current control
85	- CHARGER_TOPOFF: end of charge current threshold level
86
87The bindings inside the regulator nodes use the standard regulator bindings
88which are documented elsewhere.
89
90Example:
91
92	max8997_pmic@66 {
93		compatible = "maxim,max8997-pmic";
94		interrupt-parent = <&wakeup_eint>;
95		reg = <0x66>;
96		interrupts = <4 0>, <3 0>;
97
98		max8997,pmic-buck1-uses-gpio-dvs;
99		max8997,pmic-buck2-uses-gpio-dvs;
100		max8997,pmic-buck5-uses-gpio-dvs;
101
102		max8997,pmic-ignore-gpiodvs-side-effect;
103		max8997,pmic-buck125-default-dvs-idx = <0>;
104
105		max8997,pmic-buck125-dvs-gpios = <&gpx0 0 1 0 0>, /* SET1 */
106						 <&gpx0 1 1 0 0>, /* SET2 */
107						 <&gpx0 2 1 0 0>; /* SET3 */
108
109		max8997,pmic-buck1-dvs-voltage = <1350000>, <1300000>,
110						 <1250000>, <1200000>,
111						 <1150000>, <1100000>,
112						 <1000000>, <950000>;
113
114		max8997,pmic-buck2-dvs-voltage = <1100000>, <1100000>,
115						 <1100000>, <1100000>,
116						 <1000000>, <1000000>,
117						 <1000000>, <1000000>;
118
119		max8997,pmic-buck5-dvs-voltage = <1200000>, <1200000>,
120						 <1200000>, <1200000>,
121						 <1200000>, <1200000>,
122						 <1200000>, <1200000>;
123
124		regulators {
125			ldo1_reg: LDO1 {
126				regulator-name = "VDD_ABB_3.3V";
127				regulator-min-microvolt = <3300000>;
128				regulator-max-microvolt = <3300000>;
129			};
130
131			ldo2_reg: LDO2 {
132				regulator-name = "VDD_ALIVE_1.1V";
133				regulator-min-microvolt = <1100000>;
134				regulator-max-microvolt = <1100000>;
135				regulator-always-on;
136			};
137
138			buck1_reg: BUCK1 {
139				regulator-name = "VDD_ARM_1.2V";
140				regulator-min-microvolt = <950000>;
141				regulator-max-microvolt = <1350000>;
142				regulator-always-on;
143				regulator-boot-on;
144			};
145		};
146	};
147