From: Marek Vasut <marek.vasut+renesas@xxxxxxxxx>
Reword the binding document to make it clear how the propeties work
and which properties affect which other properties.
Signed-off-by: Marek Vasut <marek.vasut+renesas@xxxxxxxxx>
Cc: Harald Geyer <harald@xxxxxxxxx>
Cc: Kuninori Morimoto <kuninori.morimoto.gx@xxxxxxxxxxx>
Cc: Linus Walleij <linus.walleij@xxxxxxxxxx>
Cc: Mark Brown <broonie@xxxxxxxxxx>
Cc: Rob Herring <robh@xxxxxxxxxx>
Cc: linux-renesas-soc@xxxxxxxxxxxxxxx
To: devicetree@xxxxxxxxxxxxxxx
---
V2: - Make "gpios" a mandatory property
- Reword "gpio-states" property description
- Change "enable-gpio" to "enable-gpios" to match modern DT rules
V3: - Use gpio-states description from Harald
Note: The recent gpio-regulator rework caused breakage. While the
changes in the gpio-regulator code were according to the DT
binding document, they stopped working with older DTs. Make
the binding document clearer to prevent such breakage in the
future.
---
.../bindings/regulator/gpio-regulator.txt | 30 ++++++++++++++-----
1 file changed, 22 insertions(+), 8 deletions(-)
diff --git a/Documentation/devicetree/bindings/regulator/gpio-regulator.txt b/Documentation/devicetree/bindings/regulator/gpio-regulator.txt
index 1f496159e2bb..dd25e73b5d79 100644
--- a/Documentation/devicetree/bindings/regulator/gpio-regulator.txt
+++ b/Documentation/devicetree/bindings/regulator/gpio-regulator.txt
@@ -4,16 +4,30 @@ Required properties:
- compatible : Must be "regulator-gpio".
- regulator-name : Defined in regulator.txt as optional, but required
here.
-- states : Selection of available voltages and GPIO configs.
- if there are no states, then use a fixed regulator
+- gpios : Array of one or more GPIO pins used to select the
+ regulator voltage/current listed in "states".
+- states : Selection of available voltages/currents provided by
+ this regulator and matching GPIO configurations to
+ achieve them. If there are no states in the "states"
+ array, use a fixed regulator instead.
Optional properties:
-- enable-gpio : GPIO to use to enable/disable the regulator.
-- gpios : GPIO group used to control voltage.
-- gpios-states : gpios pin's initial states array. 0: LOW, 1: HIGH.
- defualt is LOW if nothing is specified.
+- enable-gpios : GPIO used to enable/disable the regulator.
+ Warning, the GPIO phandle flags are ignored and the
+ GPIO polarity is controlled solely by the presence
+ of "enable-active-high" DT property. This is due to
+ compatibility with old DTs.
+- enable-active-high : Polarity of "enable-gpio" GPIO is active HIGH.
+ Default is active LOW.
+- gpios-states : On operating systems, that don't support reading back
+ gpio values in output mode (most notably linux), this
+ array provides the state of GPIO pins set when
+ requesting them from the gpio controller. Systems,
+ that are capable of preserving state when requesting
+ the lines, are free to ignore this property.
+ 0: LOW, 1: HIGH. Default is LOW if nothing else
+ is specified.
- startup-delay-us : Startup time in microseconds.
-- enable-active-high : Polarity of GPIO is active high (default is low).
- regulator-type : Specifies what is being regulated, must be either
"voltage" or "current", defaults to voltage.
@@ -30,7 +44,7 @@ Example:
regulator-max-microvolt = <2600000>;
regulator-boot-on;
- enable-gpio = <&gpio0 23 0x4>;
+ enable-gpios = <&gpio0 23 0x4>;
gpios = <&gpio0 24 0x4
&gpio0 25 0x4>;
states = <1800000 0x3
--
2.20.1
