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-rw-r--r--dts/Bindings/arm/tegra/nvidia,tegra186-pmc.txt93
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diff --git a/dts/Bindings/arm/tegra/nvidia,tegra186-pmc.txt b/dts/Bindings/arm/tegra/nvidia,tegra186-pmc.txt
index 5a3bf7c5a7..c9fd6d1de5 100644
--- a/dts/Bindings/arm/tegra/nvidia,tegra186-pmc.txt
+++ b/dts/Bindings/arm/tegra/nvidia,tegra186-pmc.txt
@@ -34,3 +34,96 @@ Board DTS:
pmc@c360000 {
nvidia,invert-interrupt;
};
+
+== 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.
+
+Pad configurations are described with pin configuration nodes which
+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 following pads are present on Tegra186:
+csia csib dsi mipi-bias
+pex-clk-bias pex-clk3 pex-clk2 pex-clk1
+usb0 usb1 usb2 usb-bias
+uart audio hsic dbg
+hdmi-dp0 hdmi-dp1 pex-cntrl sdmmc2-hv
+sdmmc4 cam dsib dsic
+dsid csic csid csie
+dsif spi ufs dmic-hv
+edp sdmmc1-hv sdmmc3-hv conn
+audio-hv ao-hv
+
+Required pin configuration properties:
+ - pins: A list of strings, each of which contains the name of a pad
+ 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 above pads except
+ for ao-hv. Following pads have software configurable signaling
+ voltages: sdmmc2-hv, dmic-hv, sdmmc1-hv, sdmmc3-hv, audio-hv,
+ ao-hv.
+
+Pad configuration state example:
+ pmc: pmc@7000e400 {
+ compatible = "nvidia,tegra186-pmc";
+ reg = <0 0x0c360000 0 0x10000>,
+ <0 0x0c370000 0 0x10000>,
+ <0 0x0c380000 0 0x10000>,
+ <0 0x0c390000 0 0x10000>;
+ reg-names = "pmc", "wake", "aotag", "scratch";
+
+ ...
+
+ sdmmc1_3v3: sdmmc1-3v3 {
+ pins = "sdmmc1-hv";
+ power-source = <TEGRA_IO_PAD_VOLTAGE_3V3>;
+ };
+
+ sdmmc1_1v8: sdmmc1-1v8 {
+ pins = "sdmmc1-hv";
+ 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@3400000 {
+ ...
+ pinctrl-names = "sdmmc-3v3", "sdmmc-1v8";
+ pinctrl-0 = <&sdmmc1_3v3>;
+ pinctrl-1 = <&sdmmc1_1v8>;
+ };
+
+ ...
+
+ sor0: sor@15540000 {
+ ...
+ pinctrl-0 = <&hdmi_off>;
+ pinctrl-1 = <&hdmi_on>;
+ pinctrl-names = "hdmi-on", "hdmi-off";
+ };