diff --git a/drivers/irqchip/qcom-irq-combiner.c b/drivers/irqchip/qcom-irq-combiner.c
index 7f0c0be322e08a848bd42cc906c706315816f2c4..d269a7722032a3d668cdfff3454a41f574d0fe1e 100644
--- a/drivers/irqchip/qcom-irq-combiner.c
+++ b/drivers/irqchip/qcom-irq-combiner.c
@@ -237,7 +237,6 @@ static int get_registers(struct platform_device *pdev, struct combiner *comb)
 static int __init combiner_probe(struct platform_device *pdev)
 {
 	struct combiner *combiner;
-	size_t alloc_sz;
 	int nregs;
 	int err;
 
@@ -247,8 +246,8 @@ static int __init combiner_probe(struct platform_device *pdev)
 		return -EINVAL;
 	}
 
-	alloc_sz = sizeof(*combiner) + sizeof(struct combiner_reg) * nregs;
-	combiner = devm_kzalloc(&pdev->dev, alloc_sz, GFP_KERNEL);
+	combiner = devm_kzalloc(&pdev->dev, struct_size(combiner, regs, nregs),
+				GFP_KERNEL);
 	if (!combiner)
 		return -ENOMEM;