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-espi.c b/drivers/spi/spi-fsl-espi.c
index 428dc7a6b62e..e8e3d34bab07 100644
--- a/drivers/spi/spi-fsl-espi.c
+++ b/drivers/spi/spi-fsl-espi.c
@@ -446,7 +446,8 @@ static void fsl_espi_do_one_msg(struct spi_message *m)
 
         m->actual_length = espi_trans.actual_length;
         m->status = espi_trans.status;
-        m->complete(m->context);
+        if (m->complete)
+                m->complete(m->context);
 }
 
 static int fsl_espi_setup(struct spi_device *spi)