atmel_spi: fix warning In function 'atmel_spi_dma_map_xfer'

passing argument 2 of 'dma_map_single' discards qualifiers from pointer target type

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/spi/atmel_spi.c b/drivers/spi/atmel_spi.c
index 154529aacc03..a067046c9da2 100644
--- a/drivers/spi/atmel_spi.c
+++ b/drivers/spi/atmel_spi.c
@@ -352,8 +352,12 @@ atmel_spi_dma_map_xfer(struct atmel_spi *as, struct spi_transfer *xfer)
 
         xfer->tx_dma = xfer->rx_dma = INVALID_DMA_ADDRESS;
         if (xfer->tx_buf) {
+                /* tx_buf is a const void* where we need a void * for the dma
+                 * mapping */
+                void *nonconst_tx = (void *)xfer->tx_buf;
+
                 xfer->tx_dma = dma_map_single(dev,
-                                (void *) xfer->tx_buf, xfer->len,
+                                nonconst_tx, xfer->len,
                                 DMA_TO_DEVICE);
                 if (dma_mapping_error(dev, xfer->tx_dma))
                         return -ENOMEM;