devicetree: bindings: bd718x7: document HW state related ROHM specific properties

Add ROHM BD71837 / BD71847 specific device tree bindings for
controlling the PMIC shutdown/reset states and voltages for
different HW states. The PMIC was designed to be used with NXP
i.MX8 SoC and it supports SNVS low power state which seems to
be typical for NXP i.MX SoCs. However, when SNVS is used we must
not allow SW to control enabling/disabling those regulators which
are crucial for system to boot as there is a HW limitation which
causes SW controlled regulators to be kept shut down after SNVS
reset.

Allow setting the SNVS to be used as reset target state and allow
marking those regulators which are critical for boot.

Signed-off-by: Matti Vaittinen <matti.vaittinen@fi.rohmeurope.com>
Tested-by: Angus Ainslie <angus@akkea.ca>
Reviewed-by: Angus Ainslie <angus@akkea.ca>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 38 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/regulator/rohm,bd71837-regulator.txt b/Documentation/devicetree/bindings/regulator/rohm,bd71837-regulator.txt
index 4b98ca26e61a..cbce62c22b60 100644
--- a/Documentation/devicetree/bindings/regulator/rohm,bd71837-regulator.txt
+++ b/Documentation/devicetree/bindings/regulator/rohm,bd71837-regulator.txt
@@ -27,8 +27,38 @@ BUCK1, BUCK2, BUCK3, BUCK4, BUCK5, BUCK6
 LDO1, LDO2, LDO3, LDO4, LDO5, LDO6
 
 Optional properties:
+- rohm,dvs-run-voltage		: PMIC default "RUN" state voltage in uV.
+				  See below table for bucks which support this.
+- rohm,dvs-idle-voltage		: PMIC default "IDLE" state voltage in uV.
+				  See below table for bucks which support this.
+- rohm,dvs-suspend-voltage	: PMIC default "SUSPEND" state voltage in uV.
+				  See below table for bucks which support this.
 - Any optional property defined in bindings/regulator/regulator.txt
 
+Supported default DVS states:
+
+BD71837:
+buck	| dvs-run-voltage	| dvs-idle-voltage	| dvs-suspend-voltage
+-----------------------------------------------------------------------------
+1	| supported		| supported		| supported
+----------------------------------------------------------------------------
+2	| supported		| supported		| not supported
+----------------------------------------------------------------------------
+3	| supported		| not supported		| not supported
+----------------------------------------------------------------------------
+4	| supported		| not supported		| not supported
+----------------------------------------------------------------------------
+rest	| not supported		| not supported		| not supported
+
+BD71847:
+buck	| dvs-run-voltage	| dvs-idle-voltage	| dvs-suspend-voltage
+-----------------------------------------------------------------------------
+1	| supported		| supported		| supported
+----------------------------------------------------------------------------
+2	| supported		| supported		| not supported
+----------------------------------------------------------------------------
+rest	| not supported		| not supported		| not supported
+
 Example:
 regulators {
 	buck1: BUCK1 {
@@ -36,7 +66,11 @@ regulators {
 		regulator-min-microvolt = <700000>;
 		regulator-max-microvolt = <1300000>;
 		regulator-boot-on;
+		regulator-always-on;
 		regulator-ramp-delay = <1250>;
+		rohm,dvs-run-voltage = <900000>;
+		rohm,dvs-idle-voltage = <850000>;
+		rohm,dvs-suspend-voltage = <800000>;
 	};
 	buck2: BUCK2 {
 		regulator-name = "buck2";
@@ -45,18 +79,22 @@ regulators {
 		regulator-boot-on;
 		regulator-always-on;
 		regulator-ramp-delay = <1250>;
+		rohm,dvs-run-voltage = <1000000>;
+		rohm,dvs-idle-voltage = <900000>;
 	};
 	buck3: BUCK3 {
 		regulator-name = "buck3";
 		regulator-min-microvolt = <700000>;
 		regulator-max-microvolt = <1300000>;
 		regulator-boot-on;
+		rohm,dvs-run-voltage = <1000000>;
 	};
 	buck4: BUCK4 {
 		regulator-name = "buck4";
 		regulator-min-microvolt = <700000>;
 		regulator-max-microvolt = <1300000>;
 		regulator-boot-on;
+		rohm,dvs-run-voltage = <1000000>;
 	};
 	buck5: BUCK5 {
 		regulator-name = "buck5";