[U-Boot] [PATCH 3/6] spi: Support half-duplex mode in FDT decode

[Simon Glass]

This parameter should also be supported.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 doc/device-tree-bindings/spi/spi-bus.txt | 2 ++
 drivers/spi/spi.c                        | 2 ++
 2 files changed, 4 insertions(+)

diff --git a/doc/device-tree-bindings/spi/spi-bus.txt b/doc/device-tree-bindings/spi/spi-bus.txt
index 800dafe..5c8720a 100644
--- a/doc/device-tree-bindings/spi/spi-bus.txt
+++ b/doc/device-tree-bindings/spi/spi-bus.txt
@@ -59,6 +59,8 @@ contain the following properties.
                       used for MOSI. Defaults to 1 if not present.
 - spi-rx-bus-width - (optional) The bus width(number of data wires) that
                       used for MISO. Defaults to 1 if not present.
+- spi-half-duplex  - (optional) Indicates that the SPI bus should wait for
+		      a header byte before reading data from the slave.
 
 Some SPI controllers and devices support Dual and Quad SPI transfer mode.
 It allows data in SPI system transfered in 2 wires(DUAL) or 4 wires(QUAD).
diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 7ddea9b..7d81fbd 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -53,6 +53,8 @@ struct spi_slave *spi_base_setup_slave_fdt(const void *blob, int busnum,
 		mode |= SPI_CPHA;
 	if (fdtdec_get_bool(blob, node, "spi-cs-high"))
 		mode |= SPI_CS_HIGH;
+	if (fdtdec_get_bool(blob, node, "spi-half-duplex"))
+		mode |= SPI_PREAMBLE;
 	return spi_setup_slave(busnum, cs, max_hz, mode);
 }
 #endif
-- 
2.0.0.526.g5318336