Re: [PATCH v3 5/7] dt-bindings: Add Tegra PMC pad configuration bindings

From: Aapo Vienamo
Date: Tue Jul 17 2018 - 08:23:30 EST


On Mon, 16 Jul 2018 09:43:09 -0600
Rob Herring <robh@xxxxxxxxxx> wrote:

> On Thu, Jul 12, 2018 at 03:00:11PM +0300, Aapo Vienamo wrote:
> > Document the pinctrl bindings used by the PMC driver for performing pad
> > 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@xxxxxxxxxx>
> > Acked-by: Jon Hunter <jonathanh@xxxxxxxxxx>
> > ---
> > .../bindings/arm/tegra/nvidia,tegra186-pmc.txt | 84 +++++++++++++++++++
> > .../bindings/arm/tegra/nvidia,tegra20-pmc.txt | 95 ++++++++++++++++++++++
> > include/dt-bindings/pinctrl/pinctrl-tegra-io-pad.h | 18 ++++
> > 3 files changed, 197 insertions(+)
> > create mode 100644 include/dt-bindings/pinctrl/pinctrl-tegra-io-pad.h
> >
> > diff --git a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra186-pmc.txt b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra186-pmc.txt
> > index 5a3bf7c..9528f41 100644
> > --- a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra186-pmc.txt
> > +++ b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra186-pmc.txt
> > @@ -34,3 +34,87 @@ Board DTS:
> > pmc@c360000 {
> > nvidia,invert-interrupt;
> > };
> > +
> > +== Pad Control Nodes ==
> > +
> > +The PMC can be used to set pad power state and voltage configuration.
> > +The pad configuration is done via the pinctrl framework. The driver
> > +implements power-source, low-power-enable, and low-power-disable pinconf
> > +pin configuration node properties. Each pinctrl pin corresponds to a
> > +single Tegra PMC pad. Thus, in the following sections of this document
> > +pin refers to the pinctrl frameworks notion of a Tegra PMC pad.
>
> "pinctrl framework" is Linux specific and doesn't belong in the binding.
> Neither does what a driver supports. Describe what the h/w supports.
>
> > +
> > +The pad configuration state nodes are placed under the pmc node and they
> > +are referred to by the pinctrl client device properties. For more
>
> Another driver detail not relevant.
>
> > +information see the examples presented later and
>
> examples don't document bindings. The documentation should be complete
> without examples.
>
> > +Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt.
> > +
> > +The values accepted by power-source property are
> > +TEGRA_IO_PAD_VOLTAGE_1V8 and TEGRA_IO_PAD_VOLTAGE_3V3, which are defined
> > +in dt-bindings/pinctrl/pinctrl-tegra-io-pad.h.
>
> You need to list out what properties the child nodes can have.
>
> power-source needs a vendor prefix.

Isn't it a generic pinctrl property?

> > +
> > +Following pinctrl pin name strings 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
> > +
> > +All of the listed Tegra186 pins except ao-hv support the
> > +low-power-enable and low-power-disable properties. The power-source
> > +property is supported following Tegra210 pins: 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";
> > + };
> > diff --git a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt
> > index a74b37b..d50a505 100644
> > --- a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt
> > +++ b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra20-pmc.txt
> > @@ -195,3 +195,98 @@ Example:
> > power-domains = <&pd_audio>;
> > ...
> > };
> > +
> > +== Pad Control Nodes ==
>
> Similar comments in this file.
>
> > +
> > +The PMC can be used to set pad power state and voltage configuration.
> > +This functionality is present on SoCs from Tegra124 onwards. The pad
> > +configuration is done via the pinctrl framework. The driver implements
> > +power-source, low-power-enable, and low-power-disable pinconf pin
> > +configuration node properties. Each pinctrl pin corresponds to a single
> > +Tegra PMC pad. Thus, in the following sections of this document pin
> > +refers to the pinctrl frameworks notion of a Tegra PMC pad.
> > +
> > +The pad configuration state nodes are placed under the pmc node and they
> > +are referred to by the pinctrl client device properties. For more
> > +information see the examples presented later and
> > +Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt.
> > +
> > +The values accepted by power-source property are
> > +TEGRA_IO_PAD_VOLTAGE_1V8 and TEGRA_IO_PAD_VOLTAGE_3V3, which are defined
> > +in dt-bindings/pinctrl/pinctrl-tegra-io-pad.h.
> > +
> > +Following pinctrl pin name strings 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
> > +
> > +All of the listed Tegra124 and Tegra132 pins support the
> > +low-power-enable and low-power-disable properties. None of the pins
> > +support the power-source property.
> > +
> > +Following pinctrl pin name strings 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
> > +
> > +All of the listed Tegra210 pins except pex-cntrl support the
> > +low-power-enable and low-power-disable properties. The power-source
> > +property is supported following Tegra210 pins: 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
> > index 0000000..20f4340
> > --- /dev/null
> > +++ b/include/dt-bindings/pinctrl/pinctrl-tegra-io-pad.h
> > @@ -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@xxxxxxxxxx>
> > + */
> > +
> > +#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
> > --
> > 2.7.4
> >

-Aapo