diff --git a/Documentation/devicetree/bindings/spi/spi-pxa2xx.txt b/Documentation/devicetree/bindings/spi/spi-pxa2xx.txt
index 89b2832283e3..e30e0c2a4bce 100644
--- a/Documentation/devicetree/bindings/spi/spi-pxa2xx.txt
+++ b/Documentation/devicetree/bindings/spi/spi-pxa2xx.txt
@@ -12,6 +12,8 @@ Optional properties:
 - cs-gpios: list of GPIO chip selects. See the SPI bus bindings,
   Documentation/devicetree/bindings/spi/spi-bus.txt
 - spi-slave: Empty property indicating the SPI controller is used in slave mode.
+- ready-gpios: GPIO used to signal a SPI master that the FIFO is filled
+  and we're ready to service a transfer. Only useful in slave mode.
 
 Child nodes represent devices on the SPI bus
   See ../spi/spi-bus.txt