1Device tree binding for NVIDIA Tegra XUSB pad controller
2========================================================
3
4NOTE: It turns out that this binding isn't an accurate description of the XUSB
5pad controller. While the description is good enough for the functional subset
6required for PCIe and SATA, it lacks the flexibility to represent the features
7needed for USB. For the new binding, see ../phy/nvidia,tegra-xusb-padctl.txt.
8The binding described in this file is deprecated and should not be used.
9
10The Tegra XUSB pad controller manages a set of lanes, each of which can be
11assigned to one out of a set of different pads. Some of these pads have an
12associated PHY that must be powered up before the pad can be used.
13
14This document defines the device-specific binding for the XUSB pad controller.
15
16Refer to pinctrl-bindings.txt in this directory for generic information about
17pin controller device tree bindings and ../phy/phy-bindings.txt for details on
18how to describe and reference PHYs in device trees.
19
20Required properties:
21--------------------
22- compatible: For Tegra124, must contain "nvidia,tegra124-xusb-padctl".
23  Otherwise, must contain '"nvidia,<chip>-xusb-padctl",
24  "nvidia-tegra124-xusb-padctl"', where <chip> is tegra132 or tegra210.
25- reg: Physical base address and length of the controller's registers.
26- resets: Must contain an entry for each entry in reset-names.
27  See ../reset/reset.txt for details.
28- reset-names: Must include the following entries:
29  - padctl
30- #phy-cells: Should be 1. The specifier is the index of the PHY to reference.
31  See <dt-bindings/pinctrl/pinctrl-tegra-xusb.h> for the list of valid values.
32
33Lane muxing:
34------------
35
36Child nodes contain the pinmux configurations following the conventions from
37the pinctrl-bindings.txt document. Typically a single, static configuration is
38given and applied at boot time.
39
40Each subnode describes groups of lanes along with parameters and pads that
41they should be assigned to. The name of these subnodes is not important. All
42subnodes should be parsed solely based on their content.
43
44Each subnode only applies the parameters that are explicitly listed. In other
45words, if a subnode that lists a function but no pin configuration parameters
46implies no information about any pin configuration parameters. Similarly, a
47subnode that describes only an IDDQ parameter implies no information about
48what function the pins are assigned to. For this reason even seemingly boolean
49values are actually tristates in this binding: unspecified, off or on.
50Unspecified is represented as an absent property, and off/on are represented
51as integer values 0 and 1.
52
53Required properties:
54- nvidia,lanes: An array of strings. Each string is the name of a lane.
55
56Optional properties:
57- nvidia,function: A string that is the name of the function (pad) that the
58  pin or group should be assigned to. Valid values for function names are
59  listed below.
60- nvidia,iddq: Enables IDDQ mode of the lane. (0: no, 1: yes)
61
62Note that not all of these properties are valid for all lanes. Lanes can be
63divided into three groups:
64
65  - otg-0, otg-1, otg-2:
66
67    Valid functions for this group are: "snps", "xusb", "uart", "rsvd".
68
69    The nvidia,iddq property does not apply to this group.
70
71  - ulpi-0, hsic-0, hsic-1:
72
73    Valid functions for this group are: "snps", "xusb".
74
75    The nvidia,iddq property does not apply to this group.
76
77  - pcie-0, pcie-1, pcie-2, pcie-3, pcie-4, sata-0:
78
79    Valid functions for this group are: "pcie", "usb3", "sata", "rsvd".
80
81
82Example:
83========
84
85SoC file extract:
86-----------------
87
88	padctl@7009f000 {
89		compatible = "nvidia,tegra124-xusb-padctl";
90		reg = <0x0 0x7009f000 0x0 0x1000>;
91		resets = <&tegra_car 142>;
92		reset-names = "padctl";
93
94		#phy-cells = <1>;
95	};
96
97Board file extract:
98-------------------
99
100	pcie-controller@1003000 {
101		...
102
103		phys = <&padctl 0>;
104		phy-names = "pcie";
105
106		...
107	};
108
109	...
110
111	padctl: padctl@7009f000 {
112		pinctrl-0 = <&padctl_default>;
113		pinctrl-names = "default";
114
115		padctl_default: pinmux {
116			usb3 {
117				nvidia,lanes = "pcie-0", "pcie-1";
118				nvidia,function = "usb3";
119				nvidia,iddq = <0>;
120			};
121
122			pcie {
123				nvidia,lanes = "pcie-2", "pcie-3",
124					       "pcie-4";
125				nvidia,function = "pcie";
126				nvidia,iddq = <0>;
127			};
128
129			sata {
130				nvidia,lanes = "sata-0";
131				nvidia,function = "sata";
132				nvidia,iddq = <0>;
133			};
134		};
135	};
136