diff --git a/drivers/irqchip/irq-sun4i.c b/drivers/irqchip/irq-sun4i.c
index 003a146..6fcef4a 100644
--- a/drivers/irqchip/irq-sun4i.c
+++ b/drivers/irqchip/irq-sun4i.c
@@ -41,16 +41,11 @@
 static void sun4i_irq_ack(struct irq_data *irqd)
 {
 	unsigned int irq = irqd_to_hwirq(irqd);
-	unsigned int irq_off = irq % 32;
-	int reg = irq / 32;
-	u32 val;
 
 	if (irq != 0)
 		return; /* Only IRQ 0 / the ENMI needs to be acked */
 
-	val = readl(sun4i_irq_base + SUN4I_IRQ_PENDING_REG(reg));
-	writel(val | (1 << irq_off),
-	       sun4i_irq_base + SUN4I_IRQ_PENDING_REG(reg));
+	writel(BIT(0), sun4i_irq_base + SUN4I_IRQ_PENDING_REG(0));
 }
 
 static void sun4i_irq_mask(struct irq_data *irqd)