ARM: tegra: document use of standard DMA DT bindings

Update all the Tegra DT bindings to require the standard dmas/dma-names
properties rather than non-standard nvidia,dma-request-selector property.

This is a DT-ABI-incompatible change. It is the second of two changes
required for me to consider the Tegra DT bindings as stable, the other
being the previous conversion to the common reset bindings.

Signed-off-by: Stephen Warren <swarren@nvidia.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/dma/tegra20-apbdma.txt b/Documentation/devicetree/bindings/dma/tegra20-apbdma.txt
index e0b166a7f04a..c6908e7c42cc 100644
--- a/Documentation/devicetree/bindings/dma/tegra20-apbdma.txt
+++ b/Documentation/devicetree/bindings/dma/tegra20-apbdma.txt
@@ -11,6 +11,10 @@ Required properties:
   See ../reset/reset.txt for details.
 - reset-names : Must include the following entries:
   - dma
+- #dma-cells : Must be <1>. This dictates the length of DMA specifiers in
+  client nodes' dmas properties. The specifier represents the DMA request
+  select value for the peripheral. For more details, consult the Tegra TRM's
+  documentation of the APB DMA channel control register REQ_SEL field.
 
 Examples:
 
@@ -36,4 +40,5 @@ apbdma: dma@6000a000 {
 	clocks = <&tegra_car 34>;
 	resets = <&tegra_car 34>;
 	reset-names = "dma";
+	#dma-cells = <1>;
 };