Doc: DT: Add binding document for MAX16989 regulator driver
Laxman Dewangan [Fri, 24 Apr 2015 10:18:38 +0000 (15:18 +0530)]
MAXIM MAX16989 is the automotive low voltage 2-channel step down
controller. Add the DT binding document detailing all properties
from DT which helps to configure the device as per requirements.

bug 1627041

Change-Id: I6527924e1a3c105bb0f717ff6791bf9c3ab3e7b3
Signed-off-by: Laxman Dewangan <ldewangan@nvidia.com>
Reviewed-on: http://git-master/r/735600

Documentation/devicetree/bindings/regulator/max16989-regulator.txt [new file with mode: 0644]

diff --git a/Documentation/devicetree/bindings/regulator/max16989-regulator.txt b/Documentation/devicetree/bindings/regulator/max16989-regulator.txt
new file mode 100644 (file)
index 0000000..0fa8136
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+Maxim MAX16989 Automotive Low-voltage 2-channel Step-Down controller.
+Device supportss two voltage output and there is 2 sets of registers
+for voltage output vout1 and vout2. These outputs are independent and
+their input/control pins are also different. Theire is 2 i2c address
+for the device, one for vout1 and other for vout2.
+
+The properties defined here is single voltage output. Two nodes are
+needed for 22 voltage outputs.
+
+Required properties:
+- compatible:  must be "maxim,max16989"
+- reg:         The i2c slave address of the regulator.
+
+Any standard regulator properties (Documentation/devicetree/bindings/regulator/
+regulator.txt) can be used to configure the voltage output of this device.
+
+Optional properties:
+- regulator-voltage-steps: Voltage steps. Must be 10000uV or 12500uV.
+       Absence of this property will set voltage steps to 12500mV.
+- maxim,enabke-clk-spread-spectrum: Boolean, Enable clock 3% spread spectrum.
+- maxim,enable-gpio: GPIO number connected to EN pin to enable/disable the
+       voltage output.
+- maxim,enable-external-fpwm: Boolean, enable extern control FPWM. The
+       FPWM will be controlled by SYNC IO control signal.
+- maxim,fpwm-sync-gpio: GPIO number connected to SYNC IO pin from Host to
+       control the FPWM/SKIP mode. If valid GPIO is provided then external
+       control of FPWM will be selected even if property "maxim,enable-
+       external-fpwm" is not available.
+- maxim,enable-sync-output: Boolean, Enable sync pin as output.
+- maxim,tracking-device-i2c-address: I2C address of the MAX20024 which is
+       used for LDO4 voltage tracking. If this property is available and
+       voltage step is 12500uV then tracking will be enabled.
+-maxim,slew-rate: Slew rate configuration for soft start and rising dvs
+       in mV/us. Tables are
+       Soft startup(mV/us)     Rising DVS (mV/us)      value
+               22                      22              0
+               11                      22              1
+               5.5                     22              2
+               11                      11              3
+               5.5                     11              4
+               5.5                     5.5             5
+
+Maximum voltage is selected from regulator-max-microvolt property. If this
+is not provided then it will be assumed that the maximum voltage is the
+device supported maximum voltage.
+
+All GPIOs numbers are provided as per the DT binding document
+(Documentation/devicetree/bindings/gpio/gpio.txt).
+
+Example:
+
+       max16989@1b {
+               compatible = "maxim,max16989";
+               reg = <0x1b>;
+
+               regulator-min-microvolt = <935000>;
+               regulator-max-microvolt = <1200000>;
+               maxim,enable-gpio = <&gpio 20 0>;
+       };