spi: bcm2835: enable support of 3-wire mode

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c
index 8de1925fe554..3f93718aad3f 100644
--- a/drivers/spi/spi-bcm2835.c
+++ b/drivers/spi/spi-bcm2835.c
@@ -67,7 +67,8 @@
 #define BCM2835_SPI_CS_CS_01            0x00000001
 
 #define BCM2835_SPI_TIMEOUT_MS  30000
-#define BCM2835_SPI_MODE_BITS   (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH | SPI_NO_CS)
+#define BCM2835_SPI_MODE_BITS   (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
+                                | SPI_NO_CS | SPI_3WIRE)
 
 #define DRV_NAME        "spi-bcm2835"
 
@@ -163,6 +164,9 @@ static int bcm2835_spi_start_transfer(struct spi_device *spi,
                 cdiv = 0; /* 0 is the slowest we can go */
         }
 
+        if ((spi->mode & SPI_3WIRE) && (tfr->rx_buf))
+                cs |= BCM2835_SPI_CS_REN;
+
         if (spi->mode & SPI_CPOL)
                 cs |= BCM2835_SPI_CS_CPOL;
         if (spi->mode & SPI_CPHA)