spi: Always check complete callback before calling it

Since commit 1e25cd4729bd "spi: Do not require a completion", this checking is
required to prevent NULL pointer dereference.

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

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/spi/spi-fsl-spi.c b/drivers/spi/spi-fsl-spi.c
index 119f7af94537..f2af3eb3ceb7 100644
--- a/drivers/spi/spi-fsl-spi.c
+++ b/drivers/spi/spi-fsl-spi.c
@@ -404,7 +404,8 @@ static void fsl_spi_do_one_msg(struct spi_message *m)
         }
 
         m->status = status;
-        m->complete(m->context);
+        if (m->complete)
+                m->complete(m->context);
 
         if (status || !cs_change) {
                 ndelay(nsecs);