[PATCH] spi: pl022: Document property values

[Antonio Borneo]

The property "pl022,com-mode" can only assume one of the values of
the enum ssp_mode, defined in include/linux/amba/pl022.h
List the possible numeric values and report the associated meaning.

Signed-off-by: Antonio Borneo <borneo.antonio@xxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
 Documentation/devicetree/bindings/spi/spi_pl022.txt | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/spi/spi_pl022.txt b/Documentation/devicetree/bindings/spi/spi_pl022.txt
index 2692a5726c3f..7638b4968ddb 100644
--- a/Documentation/devicetree/bindings/spi/spi_pl022.txt
+++ b/Documentation/devicetree/bindings/spi/spi_pl022.txt
@@ -30,7 +30,10 @@ contain the following properties.
 	0: SPI
 	1: Texas Instruments Synchronous Serial Frame Format
 	2: Microwire (Half Duplex)
-- pl022,com-mode : polling, interrupt or dma
+- pl022,com-mode : specifies the transfer mode:
+	0: interrupt mode
+	1: polling mode (default mode if property not present)
+	2: DMA mode
 - pl022,rx-level-trig : Rx FIFO watermark level
 - pl022,tx-level-trig : Tx FIFO watermark level
 - pl022,ctrl-len : Microwire interface: Control length
-- 
2.11.0