spi/xilinx: Support for spi mode LOOP

Hardware supports LOOP mode. Support it also in the driver.

Signed-off-by: Ricardo Ribalda Delgado <ricardo.ribalda@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

1 files changed, 4 insertions, 2 deletions

diff --git a/drivers/spi/spi-xilinx.c b/drivers/spi/spi-xilinx.c
index d4edeeeabbc3..e1d9a2003ae6 100644
--- a/drivers/spi/spi-xilinx.c
+++ b/drivers/spi/spi-xilinx.c
@@ -35,7 +35,7 @@
 #define XSPI_CR_CPOL            0x08
 #define XSPI_CR_CPHA            0x10
 #define XSPI_CR_MODE_MASK       (XSPI_CR_CPHA | XSPI_CR_CPOL | \
-                                 XSPI_CR_LSB_FIRST)
+                                 XSPI_CR_LSB_FIRST | XSPI_CR_LOOP)
 #define XSPI_CR_TXFIFO_RESET    0x20
 #define XSPI_CR_RXFIFO_RESET    0x40
 #define XSPI_CR_MANUAL_SSELECT  0x80
@@ -197,6 +197,8 @@ static void xilinx_spi_chipselect(struct spi_device *spi, int is_on)
                         cr |= XSPI_CR_CPOL;
                 if (spi->mode & SPI_LSB_FIRST)
                         cr |= XSPI_CR_LSB_FIRST;
+                if (spi->mode & SPI_LOOP)
+                        cr |= XSPI_CR_LOOP;
                 xspi->write_fn(cr, xspi->regs + XSPI_CR_OFFSET);
 
                 /* We do not check spi->max_speed_hz here as the SPI clock
@@ -356,7 +358,7 @@ static int xilinx_spi_probe(struct platform_device *pdev)
                 return -ENODEV;
 
         /* the spi->mode bits understood by this driver: */
-        master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST;
+        master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST | SPI_LOOP;
 
         xspi = spi_master_get_devdata(master);
         xspi->bitbang.master = master;