drivers/perf: fix return value check in ali_drw_pmu_probe()

In case of error, devm_ioremap_resource() returns ERR_PTR(),
and never returns NULL. The NULL test in the return value
check should be replaced with IS_ERR().

Fixes: cf7b61073e45 ("drivers/perf: add DDR Sub-System Driveway PMU driver for Yitian 710 SoC")
Signed-off-by: Sun Ke <sunke32@huawei.com>
Acked-by: Will Deacon <will@kernel.org>
Reviewed-by: Shuai Xue <xueshuai@linux.alibaba.com>
Link: https://lore.kernel.org/r/20220924032127.313156-1-sunke32@huawei.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>

diff --git a/drivers/perf/alibaba_uncore_drw_pmu.c b/drivers/perf/alibaba_uncore_drw_pmu.c
index 82729b874f093ca18e7d3c63b84eeec9b6d18ca4..a7689fecb49d9611eb2b6f335f1212180e638660 100644 (file)
--- a/drivers/perf/alibaba_uncore_drw_pmu.c
+++ b/drivers/perf/alibaba_uncore_drw_pmu.c
@@ -658,8 +658,8 @@ static int ali_drw_pmu_probe(struct platform_device *pdev)
 
        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        drw_pmu->cfg_base = devm_ioremap_resource(&pdev->dev, res);
-       if (!drw_pmu->cfg_base)
-               return -ENOMEM;
+       if (IS_ERR(drw_pmu->cfg_base))
+               return PTR_ERR(drw_pmu->cfg_base);
 
        name = devm_kasprintf(drw_pmu->dev, GFP_KERNEL, "ali_drw_%llx",
                              (u64) (res->start >> ALI_DRW_PMU_PA_SHIFT));