spi: atmel: Make current_remaining_bytes to be int

Don't use unsigned for current_remaining_bytes so we can check
current_remaining_bytes < 0 case.
Use int is enough for current_remaining_bytes.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Wenyou Yang <wenyou.yang@atmel.com>
Signed-off-by: Mark Brown <broonie@linaro.org>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/spi/spi-atmel.c b/drivers/spi/spi-atmel.c
index 8005f9869481..485e6cce94bf 100644
--- a/drivers/spi/spi-atmel.c
+++ b/drivers/spi/spi-atmel.c
@@ -224,7 +224,7 @@ struct atmel_spi {
         struct platform_device  *pdev;
 
         struct spi_transfer     *current_transfer;
-        unsigned long           current_remaining_bytes;
+        int                     current_remaining_bytes;
         int                     done_status;
 
         struct completion       xfer_completion;
@@ -1110,6 +1110,8 @@ static int atmel_spi_one_transfer(struct spi_master *master,
                                 atmel_spi_next_xfer_pio(master, xfer);
                         } else {
                                 as->current_remaining_bytes -= len;
+                                if (as->current_remaining_bytes < 0)
+                                        as->current_remaining_bytes = 0;
                         }
                 } else {
                         atmel_spi_next_xfer_pio(master, xfer);