can: mpc5xxx_can: check of_iomap return before use

of_iomap() can return NULL so that return needs to be checked and NULL
treated as failure. While at it also take care of the missing
of_node_put() in the error path.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Fixes: commit afa17a500a36 ("net/can: add driver for mscan family & mpc52xx_mscan")
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

diff --git a/drivers/net/can/mscan/mpc5xxx_can.c b/drivers/net/can/mscan/mpc5xxx_can.c
index c7427bd..2949a38 100644 (file)
--- a/drivers/net/can/mscan/mpc5xxx_can.c
+++ b/drivers/net/can/mscan/mpc5xxx_can.c
@@ -86,6 +86,11 @@ static u32 mpc52xx_can_get_clock(struct platform_device *ofdev,
                return 0;
        }
        cdm = of_iomap(np_cdm, 0);
+       if (!cdm) {
+               of_node_put(np_cdm);
+               dev_err(&ofdev->dev, "can't map clock node!\n");
+               return 0;
+       }
 
        if (in_8(&cdm->ipb_clk_sel) & 0x1)
                freq *= 2;