Merge tag 'devicetree-for-3.14' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

  Devicetree (DT) ABI

I. Regarding stable bindings/ABI, we quote from the 2013 ARM mini-summit

   summary document:

     "That still leaves the question of, what does a stable binding look

     like?  Certainly a stable binding means that a newer kernel will not

     break on an older device tree, but that doesn't mean the binding is

     frozen for all time. Grant said there are ways to change bindings that

     don't result in breakage. For instance, if a new property is added,

     then default to the previous behaviour if it is missing. If a binding

     truly needs an incompatible change, then change the compatible string

     at the same time.  The driver can bind against both the old and the

     new. These guidelines aren't new, but they desperately need to be

     documented."

II.  General binding rules

  1) Maintainers, don't let perfect be the enemy of good.  Don't hold up a

     binding because it isn't perfect.

  2) Use specific compatible strings so that if we need to add a feature (DMA)

     in the future, we can create a new compatible string.  See I.

  3) Bindings can be augmented, but the driver shouldn't break when given

     the old binding. ie. add additional properties, but don't change the

     meaning of an existing property. For drivers, default to the original

     behaviour when a newly added property is missing.

  4) Don't submit bindings for staging or unstable.  That will be decided by

     the devicetree maintainers *after* discussion on the mailinglist.

III. Notes

  1) This document is intended as a general familiarization with the process as

     decided at the 2013 Kernel Summit.  When in doubt, the current word of the

     devicetree maintainers overrules this document.  In that situation, a patch

     updating this document would be appreciated.

Main node required properties:

- compatible : should be one of:

	"arm,gic-400"

	"arm,cortex-a15-gic"

	"arm,cortex-a9-gic"

	"arm,cortex-a7-gic"

tree.  Those nodes are designated as clock providers.  Clock consumer

nodes use a phandle and clock specifier pair to connect clock provider

outputs to clock inputs.  Similar to the gpio specifiers, a clock

specifier is an array of one more more cells identifying the clock

specifier is an array of zero, one or more cells identifying the clock

output on a device.  The length of a clock specifier is defined by the

value of a #clock-cells property in the clock provider node.

   Required properties:

     - #address-cells : Should be <1>

     - #size-cells : Should be <0>

     - device_type : Should be "mdio"

     - compatible : Should be "marvell,mv64360-mdio"

   Example:

     mdio {

	     #address-cells = <1>;

	     #size-cells = <0>;

	     device_type = "mdio";

	     compatible = "marvell,mv64360-mdio";

	     ethernet-phy@0 {

   Ethernet port node

   Required properties:

     - device_type : Should be "network".

     - compatible : Should be "marvell,mv64360-eth".

     - reg : Should be <0>, <1>, or <2>, according to which registers

       within the silicon block the device uses.

   Example Discovery Ethernet port node:

     ethernet@0 {

	     device_type = "network";

	     compatible = "marvell,mv64360-eth";

	     reg = <0>;

	     interrupts = <32>;

   c) Marvell Discovery PHY nodes

   Required properties:

     - device_type : Should be "ethernet-phy"

     - interrupts : <a> where a is the interrupt number for this phy.

     - interrupt-parent : the phandle for the interrupt controller that

       services interrupts for this device.

   Example Discovery PHY node:

     ethernet-phy@1 {

	     device_type = "ethernet-phy";

	     compatible = "broadcom,bcm5421";

	     interrupts = <76>;      /* GPP 12 */

	     interrupt-parent = <&PIC>;

   serial port.

   Required properties:

     - device_type : "serial"

     - compatible : "marvell,mv64360-mpsc"

     - reg : Offset and length of the register set for this device

     - sdma : the phandle for the SDMA node used by this port

   Example Discovery MPSCINTR node:

     mpsc@8000 {

	     device_type = "serial";

	     compatible = "marvell,mv64360-mpsc";

	     reg = <0x8000 0x38>;

	     virtual-reg = <0xf1008000>;

- interrupts: Should contain macb interrupt

- phy-mode: String, operation mode of the PHY interface.

  Supported values are: "mii", "rmii", "gmii", "rgmii".

- clock-names: Tuple listing input clock names.

	Required elements: 'pclk', 'hclk'

	Optional elements: 'tx_clk'

- clocks: Phandles to input clocks.

Optional properties:

- local-mac-address: 6 bytes, mac address

		interrupts = <21>;

		phy-mode = "rmii";

		local-mac-address = [3a 0e 03 04 05 06];

		clock-names = "pclk", "hclk", "tx_clk";

		clocks = <&clkc 30>, <&clkc 30>, <&clkc 13>;

	};