2 files changed, 12 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/tty/serial/fsl-mxs-auart.txt b/Documentation/devicetree/bindings/tty/serial/fsl-mxs-auart.txt
index 2ee903fad25c..273a8d5b3300 100644
--- a/Documentation/devicetree/bindings/tty/serial/fsl-mxs-auart.txt
+++ b/Documentation/devicetree/bindings/tty/serial/fsl-mxs-auart.txt
@@ -6,11 +6,19 @@ Required properties:
 - reg : Address and length of the register set for the device
 - interrupts : Should contain the auart interrupt numbers
 
+Optional properties:
+- fsl,auart-dma-channel : The DMA channels, the first is for RX, the other
+		is for TX. If you add this property, it also means that you
+		will enable the DMA support for the auart.
+		Note: due to the hardware bug in imx23(see errata : 2836),
+		only the imx28 can enable the DMA support for the auart.
+
 Example:
 auart0: serial@8006a000 {
 	compatible = "fsl,imx28-auart", "fsl,imx23-auart";
 	reg = <0x8006a000 0x2000>;
 	interrupts = <112 70 71>;
+	fsl,auart-dma-channel = <8 9>;
 };
 
 Note: Each auart port should have an alias correctly numbered in "aliases"
diff --git a/Documentation/devicetree/bindings/tty/serial/of-serial.txt b/Documentation/devicetree/bindings/tty/serial/of-serial.txt
index ba385f2e0ddc..1e1145ca4f3c 100644
--- a/Documentation/devicetree/bindings/tty/serial/of-serial.txt
+++ b/Documentation/devicetree/bindings/tty/serial/of-serial.txt
@@ -14,7 +14,10 @@ Required properties:
 	- "serial" if the port type is unknown.
 - reg : offset and length of the register set for the device.
 - interrupts : should contain uart interrupt.
-- clock-frequency : the input clock frequency for the UART.
+- clock-frequency : the input clock frequency for the UART
+	 or
+  clocks phandle to refer to the clk used as per Documentation/devicetree
+  /bindings/clock/clock-bindings.txt
 
 Optional properties:
 - current-speed : the current active speed of the UART.