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+Generic device tree bindings for I2C busses
+===========================================
+
+This document describes generic bindings which can be used to describe I2C
+busses in a device tree.
+
+Required properties
+-------------------
+
+- #address-cells - should be <1>. Read more about addresses below.
+- #size-cells - should be <0>.
+- compatible - name of I2C bus controller following generic names
+ recommended practice.
+
+For other required properties e.g. to describe register sets,
+clocks, etc. check the binding documentation of the specific driver.
+
+The cells properties above define that an address of children of an I2C bus
+are described by a single value. This is usually a 7 bit address. However,
+flags can be attached to the address. I2C_TEN_BIT_ADDRESS is used to mark a 10
+bit address. It is needed to avoid the ambiguity between e.g. a 7 bit address
+of 0x50 and a 10 bit address of 0x050 which, in theory, can be on the same bus.
+Another flag is I2C_OWN_SLAVE_ADDRESS to mark addresses on which we listen to
+be devices ourselves.
+
+Optional properties
+-------------------
+
+These properties may not be supported by all drivers. However, if a driver
+wants to support one of the below features, it should adapt the bindings below.
+
+- clock-frequency - frequency of bus clock in Hz.
+- wakeup-source - device can be used as a wakeup source.
+
+- interrupts - interrupts used by the device.
+- interrupt-names - "irq" and "wakeup" names are recognized by I2C core,
+ other names are left to individual drivers.
+
+Binding may contain optional "interrupts" property, describing interrupts
+used by the device. I2C core will assign "irq" interrupt (or the very first
+interrupt if not using interrupt names) as primary interrupt for the slave.
+
+Also, if device is marked as a wakeup source, I2C core will set up "wakeup"
+interrupt for the device. If "wakeup" interrupt name is not present in the
+binding, then primary interrupt will be used as wakeup interrupt.