forked from Minki/linux
cfd2cedb48
Some regulators (some PWM regulators) have the voltage transition exponentially. On such cases, the settling time for voltage change is treated as constant time. Add DT property for providing the settling time for any level of voltage change for non-linear voltage change. signed-off-by: Laxman Dewangan <ldewangan@nvidia.com> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Mark Brown <broonie@kernel.org>
108 lines
4.5 KiB
Plaintext
108 lines
4.5 KiB
Plaintext
Voltage/Current Regulators
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Optional properties:
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- regulator-name: A string used as a descriptive name for regulator outputs
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- regulator-min-microvolt: smallest voltage consumers may set
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- regulator-max-microvolt: largest voltage consumers may set
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- regulator-microvolt-offset: Offset applied to voltages to compensate for voltage drops
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- regulator-min-microamp: smallest current consumers may set
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- regulator-max-microamp: largest current consumers may set
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- regulator-input-current-limit-microamp: maximum input current regulator allows
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- regulator-always-on: boolean, regulator should never be disabled
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- regulator-boot-on: bootloader/firmware enabled regulator
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- regulator-allow-bypass: allow the regulator to go into bypass mode
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- regulator-allow-set-load: allow the regulator performance level to be configured
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- <name>-supply: phandle to the parent supply/regulator node
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- regulator-ramp-delay: ramp delay for regulator(in uV/us)
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For hardware which supports disabling ramp rate, it should be explicitly
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initialised to zero (regulator-ramp-delay = <0>) for disabling ramp delay.
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- regulator-enable-ramp-delay: The time taken, in microseconds, for the supply
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rail to reach the target voltage, plus/minus whatever tolerance the board
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design requires. This property describes the total system ramp time
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required due to the combination of internal ramping of the regulator itself,
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and board design issues such as trace capacitance and load on the supply.
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- regulator-settling-time-us: Settling time, in microseconds, for voltage
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change if regulator have the constant time for any level voltage change.
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This is useful when regulator have exponential voltage change.
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- regulator-soft-start: Enable soft start so that voltage ramps slowly
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- regulator-state-mem sub-root node for Suspend-to-RAM mode
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: suspend to memory, the device goes to sleep, but all data stored in memory,
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only some external interrupt can wake the device.
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- regulator-state-disk sub-root node for Suspend-to-DISK mode
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: suspend to disk, this state operates similarly to Suspend-to-RAM,
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but includes a final step of writing memory contents to disk.
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- regulator-state-[mem/disk] node has following common properties:
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- regulator-on-in-suspend: regulator should be on in suspend state.
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- regulator-off-in-suspend: regulator should be off in suspend state.
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- regulator-suspend-microvolt: regulator should be set to this voltage
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in suspend.
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- regulator-mode: operating mode in the given suspend state.
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The set of possible operating modes depends on the capabilities of
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every hardware so the valid modes are documented on each regulator
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device tree binding document.
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- regulator-initial-mode: initial operating mode. The set of possible operating
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modes depends on the capabilities of every hardware so each device binding
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documentation explains which values the regulator supports.
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- regulator-system-load: Load in uA present on regulator that is not captured by
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any consumer request.
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- regulator-pull-down: Enable pull down resistor when the regulator is disabled.
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- regulator-over-current-protection: Enable over current protection.
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- regulator-active-discharge: tristate, enable/disable active discharge of
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regulators. The values are:
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0: Disable active discharge.
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1: Enable active discharge.
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Absence of this property will leave configuration to default.
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Deprecated properties:
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- regulator-compatible: If a regulator chip contains multiple
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regulators, and if the chip's binding contains a child node that
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describes each regulator, then this property indicates which regulator
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this child node is intended to configure. If this property is missing,
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the node's name will be used instead.
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Example:
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xyzreg: regulator@0 {
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regulator-min-microvolt = <1000000>;
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regulator-max-microvolt = <2500000>;
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regulator-always-on;
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vin-supply = <&vin>;
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regulator-state-mem {
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regulator-on-in-suspend;
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};
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};
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Regulator Consumers:
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Consumer nodes can reference one or more of its supplies/
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regulators using the below bindings.
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- <name>-supply: phandle to the regulator node
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These are the same bindings that a regulator in the above
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example used to reference its own supply, in which case
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its just seen as a special case of a regulator being a
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consumer itself.
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Example of a consumer device node (mmc) referencing two
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regulators (twl_reg1 and twl_reg2),
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twl_reg1: regulator@0 {
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...
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...
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...
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};
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twl_reg2: regulator@1 {
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...
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...
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...
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};
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mmc: mmc@0x0 {
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...
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...
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vmmc-supply = <&twl_reg1>;
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vmmcaux-supply = <&twl_reg2>;
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};
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