spi: ti-qspi: Make sure res_mmap != NULL before dereferencing it

resource_size() is dereferencing the res without checking that it is
not NULL, so we need to do the check before calling resource_size().

Fixes: b95cb394ab59 ("spi: ti-qspi: Implement the spi_mem interface")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

diff --git a/drivers/spi/spi-ti-qspi.c b/drivers/spi/spi-ti-qspi.c
index c54b760..5f19016 100644 (file)
--- a/drivers/spi/spi-ti-qspi.c
+++ b/drivers/spi/spi-ti-qspi.c
@@ -718,7 +718,9 @@ static int ti_qspi_probe(struct platform_device *pdev)
                                "memory mapped resource not required\n");
                }
        }
-       qspi->mmap_size = resource_size(res_mmap);
+
+       if (res_mmap)
+               qspi->mmap_size = resource_size(res_mmap);
 
        irq = platform_get_irq(pdev, 0);
        if (irq < 0) {