The current DT bindings assume that the DMA will be performed by the
devices through their parent DT node, and rely on that assumption for the
address translation using dma-ranges.

However, some SoCs have devices that will perform DMA through another bus,
with separate address translation rules. We therefore need to express that
relationship, through the special interconnect name "dma".

Signed-off-by: Maxime Ripard <maxime.rip...@bootlin.com>
---
 Documentation/devicetree/bindings/interconnect/interconnect.txt | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Documentation/devicetree/bindings/interconnect/interconnect.txt 
b/Documentation/devicetree/bindings/interconnect/interconnect.txt
index 5a3c575b387a..e69fc2d992c3 100644
--- a/Documentation/devicetree/bindings/interconnect/interconnect.txt
+++ b/Documentation/devicetree/bindings/interconnect/interconnect.txt
@@ -51,6 +51,9 @@ interconnect-names : List of interconnect path name strings 
sorted in the same
                     interconnect-names to match interconnect paths with 
interconnect
                     specifier pairs.
 
+                     Reserved interconnect names:
+                         * dma: Path from the device to the main memory of the 
system
+
 Example:
 
        sdhci@7864000 {
-- 
git-series 0.9.1
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