serial: sh-sci: Update DT binding documentation for dedicated RTS/CTS

Some Renesas SCIF UARTs have dedicated lines for RTS/CTS hardware flow
control.  Whether these lines exist depends on SoC and UART instance
inside the SoC.  Whether these lines can be used for hardware flow
control depends on board wiring.

Amend the DT bindings with an optional property to indicate that RTS/CTS
hardware flow control lines exist, and can be used as such, according to
the Generic Serial DT Bindings.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Acked-by: Rob Herring <robh@kernel.org>
Cc: devicetree@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt b/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt
index 997baeaa869baa6f98f4376f6db2c07f0b170578..7a0e15053db97481dbdd22b5bb56c134870210f1 100644 (file)
--- a/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt
+++ b/Documentation/devicetree/bindings/serial/renesas,sci-serial.txt
@@ -78,6 +78,8 @@ Optional properties:
   - dma-names: Must contain a list of two DMA names, "tx" and "rx".
   - {cts,dsr,dcd,rng,rts,dtr}-gpios: Specify GPIOs for modem lines, cfr. the
     generic serial DT bindings in serial.txt.
+  - uart-has-rtscts: Indicates dedicated lines for RTS/CTS hardware flow
+    control, cfr. the generic serial DT bindings in serial.txt.
 
 Example:
        aliases {