[RESEND][PATCHv2 1/3] ion: Devicetree bindings for Ion

This adds a base set of devicetree bindings for the Ion memory
manager. This supports setting up the generic set of heaps and
their properties.

Signed-off-by: Laura Abbott <redacted>
---
 drivers/staging/android/ion/devicetree.txt | 50 ++++++++++++++++++++++++++++++
 1 file changed, 50 insertions(+)
 create mode 100644 drivers/staging/android/ion/devicetree.txt

diff --git a/drivers/staging/android/ion/devicetree.txt b/drivers/staging/android/ion/devicetree.txt
new file mode 100644
index 0000000..e1ea537
--- /dev/null
+++ b/drivers/staging/android/ion/devicetree.txt

@@ -0,0 +1,50 @@
+Ion Memory Manager
+
+Ion is a memory manager that allows for sharing of buffers via dma-buf.
+Ion allows for different types of allocation via an abstraction called
+a 'heap'. A heap represents a specific type of memory. Each heap has
+a different type. There can be multiple instances of the same heap
+type.
+
+Required properties for Ion
+
+- compatible: "linux,ion" PLUS a compatible property for the device
+
+All child nodes of a linux,ion node are interpreted as heaps
+
+required properties for heaps
+
+- compatible: compatible string for a heap type PLUS a compatible property
+for the specific instance of the heap. Current heap types
+-- linux,ion-heap-system
+-- linux,ion-heap-system-contig
+-- linux,ion-heap-carveout
+-- linux,ion-heap-chunk
+-- linux,ion-heap-dma
+-- linux,ion-heap-custom
+
+Optional properties
+- memory-region: A phandle to a memory region. Required for DMA heap type
+(see reserved-memory.txt for details on the reservation)

+
+Example:
+
+       ion {
+               compatbile = "qcom,msm8916-ion", "linux,ion";
+               #address-cells = <1>;
+               #size-cells = <0>;
+
+               ion-system-heap {
+                       compatbile = "qcom,system-heap", "linux,ion-heap-system"
+               };

+               ion-camera-region {
+                       compatible = "qcom,camera-heap", "linux,ion-heap-dma"
+                       memory-region = <&camera_region>;