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, 4 insertions, 2 deletions

diff --git a/drivers/spi/spi-mpc52xx.c b/drivers/spi/spi-mpc52xx.c
index 7c675fe83101..a0de12ac1deb 100644
--- a/drivers/spi/spi-mpc52xx.c
+++ b/drivers/spi/spi-mpc52xx.c
@@ -235,7 +235,8 @@ static int mpc52xx_spi_fsmstate_transfer(int irq, struct mpc52xx_spi *ms,
                 dev_err(&ms->master->dev, "mode fault\n");
                 mpc52xx_spi_chipsel(ms, 0);
                 ms->message->status = -EIO;
-                ms->message->complete(ms->message->context);
+                if (ms->message->complete)
+                        ms->message->complete(ms->message->context);
                 ms->state = mpc52xx_spi_fsmstate_idle;
                 return FSM_CONTINUE;
         }
@@ -289,7 +290,8 @@ mpc52xx_spi_fsmstate_wait(int irq, struct mpc52xx_spi *ms, u8 status, u8 data)
                 ms->msg_count++;
                 mpc52xx_spi_chipsel(ms, 0);
                 ms->message->status = 0;
-                ms->message->complete(ms->message->context);
+                if (ms->message->complete)
+                        ms->message->complete(ms->message->context);
                 ms->state = mpc52xx_spi_fsmstate_idle;
                 return FSM_CONTINUE;
         }