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diff --git a/Documentation/devicetree/bindings/mfd/max77620.txt b/Documentation/devicetree/bindings/mfd/max77620.txt new file mode 100644 index 000000000..9c16d51cc --- /dev/null +++ b/Documentation/devicetree/bindings/mfd/max77620.txt @@ -0,0 +1,155 @@ +MAX77620 Power management IC from Maxim Semiconductor. + +Required properties: +------------------- +- compatible: Must be one of + "maxim,max77620" + "maxim,max20024". +- reg: I2C device address. + +Optional properties: +------------------- +- interrupts: The interrupt on the parent the controller is + connected to. +- interrupt-controller: Marks the device node as an interrupt controller. +- #interrupt-cells: is <2> and their usage is compliant to the 2 cells + variant of <../interrupt-controller/interrupts.txt> + IRQ numbers for different interrupt source of MAX77620 + are defined at dt-bindings/mfd/max77620.h. + +Optional subnodes and their properties: +======================================= + +Flexible power sequence configurations: +-------------------------------------- +The Flexible Power Sequencer (FPS) allows each regulator to power up under +hardware or software control. Additionally, each regulator can power on +independently or among a group of other regulators with an adjustable power-up +and power-down delays (sequencing). GPIO1, GPIO2, and GPIO3 can be programmed +to be part of a sequence allowing external regulators to be sequenced along +with internal regulators. 32KHz clock can be programmed to be part of a +sequence. + +The flexible sequencing structure consists of two hardware enable inputs +(EN0, EN1), and 3 master sequencing timers called FPS0, FPS1 and FPS2. +Each master sequencing timer is programmable through its configuration +register to have a hardware enable source (EN1 or EN2) or a software enable +source (SW). When enabled/disabled, the master sequencing timer generates +eight sequencing events on different time periods called slots. The time +period between each event is programmable within the configuration register. +Each regulator, GPIO1, GPIO2, GPIO3, and 32KHz clock has a flexible power +sequence slave register which allows its enable source to be specified as +a flexible power sequencer timer or a software bit. When a FPS source of +regulators, GPIOs and clocks specifies the enable source to be a flexible +power sequencer, the power up and power down delays can be specified in +the regulators, GPIOs and clocks flexible power sequencer configuration +registers. + +When FPS event cleared (set to LOW), regulators, GPIOs and 32KHz +clock are set into following state at the sequencing event that +corresponds to its flexible sequencer configuration register. + Sleep state: In this state, regulators, GPIOs + and 32KHz clock get disabled at + the sequencing event. + Global Low Power Mode (GLPM): In this state, regulators are set in + low power mode at the sequencing event. + +The configuration parameters of FPS is provided through sub-node "fps" +and their child for FPS specific. The child node name for FPS are "fps0", +"fps1", and "fps2" for FPS0, FPS1 and FPS2 respectively. + +The FPS configurations like FPS source, power up and power down slots for +regulators, GPIOs and 32kHz clocks are provided in their respective +configuration nodes which is explained in respective sub-system DT +binding document. + +There is need for different FPS configuration parameters based on system +state like when system state changed from active to suspend or active to +power off (shutdown). + +Optional properties: +------------------- +-maxim,fps-event-source: u32, FPS event source like external + hardware input to PMIC i.e. EN0, EN1 or + software (SW). + The macros are defined on + dt-bindings/mfd/max77620.h + for different control source. + - MAX77620_FPS_EVENT_SRC_EN0 + for hardware input pin EN0. + - MAX77620_FPS_EVENT_SRC_EN1 + for hardware input pin EN1. + - MAX77620_FPS_EVENT_SRC_SW + for software control. + +-maxim,shutdown-fps-time-period-us: u32, FPS time period in microseconds + when system enters in to shutdown + state. + +-maxim,suspend-fps-time-period-us: u32, FPS time period in microseconds + when system enters in to suspend state. + +-maxim,device-state-on-disabled-event: u32, describe the PMIC state when FPS + event cleared (set to LOW) whether it + should go to sleep state or low-power + state. Following are valid values: + - MAX77620_FPS_INACTIVE_STATE_SLEEP + to set the PMIC state to sleep. + - MAX77620_FPS_INACTIVE_STATE_LOW_POWER + to set the PMIC state to low + power. + Absence of this property or other value + will not change device state when FPS + event get cleared. + +Here supported time periods by device in microseconds are as follows: +MAX77620 supports 40, 80, 160, 320, 640, 1280, 2560 and 5120 microseconds. +MAX20024 supports 20, 40, 80, 160, 320, 640, 1280 and 2540 microseconds. + +-maxim,power-ok-control: configure map power ok bit + 1: Enables POK(Power OK) to control nRST_IO and GPIO1 + POK function. + 0: Disables POK control. + if property missing, do not configure MPOK bit. + If POK mapping is enabled for GPIO1/nRST_IO then, + GPIO1/nRST_IO pins are HIGH only if all rails + that have POK control enabled are HIGH. + If any of the rails goes down(which are enabled for POK + control) then, GPIO1/nRST_IO goes LOW. + this property is valid for max20024 only. + +For DT binding details of different sub modules like GPIO, pincontrol, +regulator, power, please refer respective device-tree binding document +under their respective sub-system directories. + +Example: +-------- +#include <dt-bindings/mfd/max77620.h> + +max77620@3c { + compatible = "maxim,max77620"; + reg = <0x3c>; + + interrupt-parent = <&intc>; + interrupts = <0 86 IRQ_TYPE_NONE>; + + interrupt-controller; + #interrupt-cells = <2>; + + fps { + fps0 { + maxim,shutdown-fps-time-period-us = <1280>; + maxim,fps-event-source = <MAX77620_FPS_EVENT_SRC_EN1>; + }; + + fps1 { + maxim,shutdown-fps-time-period-us = <1280>; + maxim,fps-event-source = <MAX77620_FPS_EVENT_SRC_EN0>; + }; + + fps2 { + maxim,shutdown-fps-time-period-us = <1280>; + maxim,fps-event-source = <MAX77620_FPS_EVENT_SRC_SW>; + }; + }; +}; |