xref: /linux/Documentation/devicetree/bindings/mfd/max77620.txt (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
1MAX77620 Power management IC from Maxim Semiconductor.
2
3Required properties:
4-------------------
5- compatible: Must be one of
6		"maxim,max77620"
7		"maxim,max20024".
8- reg: I2C device address.
9
10Optional properties:
11-------------------
12- interrupts:		The interrupt on the parent the controller is
13			connected to.
14- interrupt-controller: Marks the device node as an interrupt controller.
15- #interrupt-cells:	is <2> and their usage is compliant to the 2 cells
16			variant of <../interrupt-controller/interrupts.txt>
17			IRQ numbers for different interrupt source of MAX77620
18			are defined at dt-bindings/mfd/max77620.h.
19
20Optional subnodes and their properties:
21=======================================
22
23Flexible power sequence configurations:
24--------------------------------------
25The Flexible Power Sequencer (FPS) allows each regulator to power up under
26hardware or software control. Additionally, each regulator can power on
27independently or among a group of other regulators with an adjustable power-up
28and power-down delays (sequencing). GPIO1, GPIO2, and GPIO3 can be programmed
29to be part of a sequence allowing external regulators to be sequenced along
30with internal regulators. 32KHz clock can be programmed to be part of a
31sequence.
32
33The flexible sequencing structure consists of two hardware enable inputs
34(EN0, EN1), and 3 master sequencing timers called FPS0, FPS1 and FPS2.
35Each master sequencing timer is programmable through its configuration
36register to have a hardware enable source (EN1 or EN2) or a software enable
37source (SW). When enabled/disabled, the master sequencing timer generates
38eight sequencing events on different time periods called slots. The time
39period between each event is programmable within the configuration register.
40Each regulator, GPIO1, GPIO2, GPIO3, and 32KHz clock has a flexible power
41sequence slave register which allows its enable source to be specified as
42a flexible power sequencer timer or a software bit. When a FPS source of
43regulators, GPIOs and clocks specifies the enable source to be a flexible
44power sequencer, the power up and power down delays can be specified in
45the regulators, GPIOs and clocks flexible power sequencer configuration
46registers.
47
48When FPS event cleared (set to LOW), regulators, GPIOs and 32KHz
49clock are set into following state at the sequencing event that
50corresponds to its flexible sequencer configuration register.
51	Sleep state: 			In this state, regulators, GPIOs
52					and 32KHz clock get disabled at
53					the sequencing event.
54	Global Low Power Mode (GLPM):	In this state, regulators are set in
55					low power mode at the sequencing event.
56
57The configuration parameters of FPS is provided through sub-node "fps"
58and their child for FPS specific. The child node name for FPS are "fps0",
59"fps1", and "fps2" for FPS0, FPS1 and FPS2 respectively.
60
61The FPS configurations like FPS source, power up and power down slots for
62regulators, GPIOs and 32kHz clocks are provided in their respective
63configuration nodes which is explained in respective sub-system DT
64binding document.
65
66There is need for different FPS configuration parameters based on system
67state like when system state changed from active to suspend or active to
68power off (shutdown).
69
70Optional properties:
71-------------------
72-maxim,fps-event-source:		u32, FPS event source like external
73					hardware input to PMIC i.e. EN0, EN1 or
74					software (SW).
75					The macros are defined on
76						dt-bindings/mfd/max77620.h
77					for different control source.
78					- MAX77620_FPS_EVENT_SRC_EN0
79						for hardware input pin EN0.
80					- MAX77620_FPS_EVENT_SRC_EN1
81						for hardware input pin EN1.
82					- MAX77620_FPS_EVENT_SRC_SW
83						for software control.
84
85-maxim,shutdown-fps-time-period-us:	u32, FPS time period in microseconds
86					when system enters in to shutdown
87					state.
88
89-maxim,suspend-fps-time-period-us:	u32, FPS time period in microseconds
90					when system enters in to suspend state.
91
92-maxim,device-state-on-disabled-event:	u32, describe the PMIC state when FPS
93					event cleared (set to LOW) whether it
94					should go to sleep state or low-power
95					state. Following are valid values:
96					- MAX77620_FPS_INACTIVE_STATE_SLEEP
97						to set the PMIC state to sleep.
98					- MAX77620_FPS_INACTIVE_STATE_LOW_POWER
99						to set the PMIC state to low
100						power.
101					Absence of this property or other value
102					will not change device state when FPS
103					event get cleared.
104
105Here supported time periods by device in microseconds are as follows:
106MAX77620 supports 40, 80, 160, 320, 640, 1280, 2560 and 5120 microseconds.
107MAX20024 supports 20, 40, 80, 160, 320, 640, 1280 and 2540 microseconds.
108
109-maxim,power-ok-control: configure map power ok bit
110			1: Enables POK(Power OK) to control nRST_IO and GPIO1
111			POK function.
112			0: Disables POK control.
113			if property missing, do not configure MPOK bit.
114			If POK mapping is enabled for GPIO1/nRST_IO then,
115			GPIO1/nRST_IO pins are HIGH only if all rails
116			that have POK control enabled are HIGH.
117			If any of the rails goes down(which are enabled for POK
118			control) then, GPIO1/nRST_IO goes LOW.
119			this property is valid for max20024 only.
120
121For DT binding details of different sub modules like GPIO, pincontrol,
122regulator, power, please refer respective device-tree binding document
123under their respective sub-system directories.
124
125Example:
126--------
127#include <dt-bindings/mfd/max77620.h>
128
129max77620@3c {
130	compatible = "maxim,max77620";
131	reg = <0x3c>;
132
133	interrupt-parent = <&intc>;
134	interrupts = <0 86 IRQ_TYPE_NONE>;
135
136	interrupt-controller;
137	#interrupt-cells = <2>;
138
139	fps {
140		fps0 {
141			maxim,shutdown-fps-time-period-us = <1280>;
142			maxim,fps-event-source = <MAX77620_FPS_EVENT_SRC_EN1>;
143		};
144
145		fps1 {
146			maxim,shutdown-fps-time-period-us = <1280>;
147			maxim,fps-event-source = <MAX77620_FPS_EVENT_SRC_EN0>;
148		};
149
150		fps2 {
151			maxim,shutdown-fps-time-period-us = <1280>;
152			maxim,fps-event-source = <MAX77620_FPS_EVENT_SRC_SW>;
153		};
154	};
155};
156