diff --git a/drivers/pci/controller/pci-msm.c b/drivers/pci/controller/pci-msm.c
index a9c3dd7c5ecb..3a6e2a7ec708 100644
--- a/drivers/pci/controller/pci-msm.c
+++ b/drivers/pci/controller/pci-msm.c
@@ -1395,7 +1395,7 @@ static void msm_pcie_write_reg(void __iomem *base, u32 offset, u32 value)
 static void msm_pcie_write_reg_field(void __iomem *base, u32 offset,
 	const u32 mask, u32 val)
 {
-	u32 shift = find_first_bit((void *)&mask, 32);
+	u32 shift = __ffs(mask);
 	u32 tmp = readl_relaxed(base + offset);
 
 	tmp &= ~mask; /* clear written bits */