devm_ioremap_resource returns an ERR_PTR value, not NULL, on failure.
A simplified version of the semantic match that finds this problem is as
follows:
// <smpl>
@@
expression e,e1;
statement S;
@@
*e = devm_ioremap_resource(...);
if (!e1) S
// </smpl>
Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Acked-by Boris BREZILLON <boris.brezillon@free-electrons.com>
Signed-off-by: Mike Turquette <mturquette@linaro.org>
 
        r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        reg = devm_ioremap_resource(&pdev->dev, r);
-       if (!reg)
+       if (IS_ERR(reg))
                return PTR_ERR(reg);
 
        clk_parent = of_clk_get_parent_name(np, 0);