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diff --git a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt
index a74b37b07e5c..cb12f33a247f 100644
--- a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt
+++ b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt
@@ -195,3 +195,106 @@ Example:
power-domains = <&pd_audio>;
...
};
+
+== Pad Control ==
+
+On Tegra SoCs a pad is a set of pins which are configured as a group.
+The pin grouping is a fixed attribute of the hardware. The PMC can be
+used to set pad power state and signaling voltage. A pad can be either
+in active or power down mode. The support for power state and signaling
+voltage configuration varies depending on the pad in question. 3.3 V and
+1.8 V signaling voltages are supported on pins where software
+controllable signaling voltage switching is available.
+
+The pad configuration state nodes are placed under the pmc node and they
+are referred to by the pinctrl client properties. For more information
+see Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt.
+The pad name should be used as the value of the pins property in pin
+configuration nodes.
+
+The following pads are present on Tegra124 and Tegra132:
+audio bb cam comp
+csia csb cse dsi
+dsib dsic dsid hdmi
+hsic hv lvds mipi-bias
+nand pex-bias pex-clk1 pex-clk2
+pex-cntrl sdmmc1 sdmmc3 sdmmc4
+sys_ddc uart usb0 usb1
+usb2 usb_bias
+
+The following pads are present on Tegra210:
+audio audio-hv cam csia
+csib csic csid csie
+csif dbg debug-nonao dmic
+dp dsi dsib dsic
+dsid emmc emmc2 gpio
+hdmi hsic lvds mipi-bias
+pex-bias pex-clk1 pex-clk2 pex-cntrl
+sdmmc1 sdmmc3 spi spi-hv
+uart usb0 usb1 usb2
+usb3 usb-bias
+
+Required pin configuration properties:
+ - pins: Must contain name of the pad(s) to be configured.
+
+Optional pin configuration properties:
+ - low-power-enable: Configure the pad into power down mode
+ - low-power-disable: Configure the pad into active mode
+ - power-source: Must contain either TEGRA_IO_PAD_VOLTAGE_1V8
+ or TEGRA_IO_PAD_VOLTAGE_3V3 to select between signaling voltages.
+ The values are defined in
+ include/dt-bindings/pinctrl/pinctrl-tegra-io-pad.h.
+
+Note: The power state can be configured on all of the Tegra124 and
+ Tegra132 pads. None of the Tegra124 or Tegra132 pads support
+ signaling voltage switching.
+
+Note: All of the listed Tegra210 pads except pex-cntrl support power
+ state configuration. Signaling voltage switching is supported on
+ following Tegra210 pads: audio, audio-hv, cam, dbg, dmic, gpio,
+ pex-cntrl, sdmmc1, sdmmc3, spi, spi-hv, and uart.
+
+Pad configuration state example:
+ pmc: pmc@7000e400 {
+ compatible = "nvidia,tegra210-pmc";
+ reg = <0x0 0x7000e400 0x0 0x400>;
+ clocks = <&tegra_car TEGRA210_CLK_PCLK>, <&clk32k_in>;
+ clock-names = "pclk", "clk32k_in";
+
+ ...
+
+ sdmmc1_3v3: sdmmc1-3v3 {
+ pins = "sdmmc1";
+ power-source = <TEGRA_IO_PAD_VOLTAGE_3V3>;
+ };
+
+ sdmmc1_1v8: sdmmc1-1v8 {
+ pins = "sdmmc1";
+ power-source = <TEGRA_IO_PAD_VOLTAGE_1V8>;
+ };
+
+ hdmi_off: hdmi-off {
+ pins = "hdmi";
+ low-power-enable;
+ }
+
+ hdmi_on: hdmi-on {
+ pins = "hdmi";
+ low-power-disable;
+ }
+ };
+
+Pinctrl client example:
+ sdmmc1: sdhci@700b0000 {
+ ...
+ pinctrl-names = "sdmmc-3v3", "sdmmc-1v8";
+ pinctrl-0 = <&sdmmc1_3v3>;
+ pinctrl-1 = <&sdmmc1_1v8>;
+ };
+ ...
+ sor@54540000 {
+ ...
+ pinctrl-0 = <&hdmi_off>;
+ pinctrl-1 = <&hdmi_on>;
+ pinctrl-names = "hdmi-on", "hdmi-off";
+ };