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diff --git a/Documentation/devicetree/bindings/i2c/i2c-pxa-pci-ce4100.txt b/Documentation/devicetree/bindings/i2c/i2c-pxa-pci-ce4100.txt
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+CE4100 I2C
+----------
+
+CE4100 has one PCI device which is described as the I2C-Controller. This
+PCI device has three PCI-bars, each bar contains a complete I2C
+controller. So we have a total of three independent I2C-Controllers
+which share only an interrupt line.
+The driver is probed via the PCI-ID and is gathering the information of
+attached devices from the devices tree.
+Grant Likely recommended to use the ranges property to map the PCI-Bar
+number to its physical address and to use this to find the child nodes
+of the specific I2C controller. This were his exact words:
+
+       Here's where the magic happens.  Each entry in
+       ranges describes how the parent pci address space
+       (middle group of 3) is translated to the local
+       address space (first group of 2) and the size of
+       each range (last cell).  In this particular case,
+       the first cell of the local address is chosen to be
+       1:1 mapped to the BARs, and the second is the
+       offset from be base of the BAR (which would be
+       non-zero if you had 2 or more devices mapped off
+       the same BAR)
+
+       ranges allows the address mapping to be described
+       in a way that the OS can interpret without
+       requiring custom device driver code.
+
+This is an example which is used on FalconFalls:
+------------------------------------------------
+        i2c-controller@b,2 {
+                #address-cells = <2>;
+                #size-cells = <1>;
+                compatible = "pci8086,2e68.2",
+                                "pci8086,2e68",
+                                "pciclass,ff0000",
+                                "pciclass,ff00";
+
+                reg = <0x15a00 0x0 0x0 0x0 0x0>;
+                interrupts = <16 1>;
+
+                /* as described by Grant, the first number in the group of
+                * three is the bar number followed by the 64bit bar address
+                * followed by size of the mapping. The bar address
+                * requires also a valid translation in parents ranges
+                * property.
+                */
+                ranges = <0 0   0x02000000 0 0xdffe0500 0x100
+                          1 0   0x02000000 0 0xdffe0600 0x100
+                          2 0   0x02000000 0 0xdffe0700 0x100>;
+
+                i2c@0 {
+                        #address-cells = <1>;
+                        #size-cells = <0>;
+                        compatible = "intel,ce4100-i2c-controller";
+
+                        /* The first number in the reg property is the
+                        * number of the bar
+                        */
+                        reg = <0 0 0x100>;
+
+                        /* This I2C controller has no devices */
+                };
+
+                i2c@1 {
+                        #address-cells = <1>;
+                        #size-cells = <0>;
+                        compatible = "intel,ce4100-i2c-controller";
+                        reg = <1 0 0x100>;
+
+                        /* This I2C controller has one gpio controller */
+                        gpio@26 {
+                                #gpio-cells = <2>;
+                                compatible = "ti,pcf8575";
+                                reg = <0x26>;
+                                gpio-controller;
+                        };
+                };
+
+                i2c@2 {
+                        #address-cells = <1>;
+                        #size-cells = <0>;
+                        compatible = "intel,ce4100-i2c-controller";
+                        reg = <2 0 0x100>;
+
+                        gpio@26 {
+                                #gpio-cells = <2>;
+                                compatible = "ti,pcf8575";
+                                reg = <0x26>;
+                                gpio-controller;
+                        };
+                };
+        };