dt-bindings: Add Tegra PMC pad configuration bindings
authorAapo Vienamo <avienamo@nvidia.com>
Fri, 10 Aug 2018 18:08:03 +0000 (21:08 +0300)
committerThierry Reding <treding@nvidia.com>
Mon, 27 Aug 2018 10:21:43 +0000 (12:21 +0200)
Document the PMC pinctrl bindings for pad power state and signaling
voltage configuration. Both nvidia,tegra186-pmc.txt and
nvidia,tegra20-pmc.txt are modified as they both cover SoC generations
for which these bindings apply.

Add a header defining Tegra PMC pad voltage configurations.

Signed-off-by: Aapo Vienamo <avienamo@nvidia.com>
Acked-by: Jon Hunter <jonathanh@nvidia.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Documentation/devicetree/bindings/arm/tegra/nvidia,tegra186-pmc.txt
Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt
include/dt-bindings/pinctrl/pinctrl-tegra-io-pad.h [new file with mode: 0644]

index 5a3bf7c..c9fd6d1 100644 (file)
@@ -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";
+       };
index a74b37b..cb12f33 100644 (file)
@@ -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";
+       };
diff --git a/include/dt-bindings/pinctrl/pinctrl-tegra-io-pad.h b/include/dt-bindings/pinctrl/pinctrl-tegra-io-pad.h
new file mode 100644 (file)
index 0000000..20f4340
--- /dev/null
@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * pinctrl-tegra-io-pad.h: Tegra I/O pad source voltage configuration constants
+ * pinctrl bindings.
+ *
+ * Copyright (c) 2018, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * Author: Aapo Vienamo <avienamo@nvidia.com>
+ */
+
+#ifndef _DT_BINDINGS_PINCTRL_TEGRA_IO_PAD_H
+#define _DT_BINDINGS_PINCTRL_TEGRA_IO_PAD_H
+
+/* Voltage levels of the I/O pad's source rail */
+#define TEGRA_IO_PAD_VOLTAGE_1V8       0
+#define TEGRA_IO_PAD_VOLTAGE_3V3       1
+
+#endif