irqchip/loongson-pch-pic: Fix the misused irq flow handler

Loongson PCH PIC is a standard level triggered PIC, and it need to clear
interrupt during unmask.

Fixes: ef8c01e ("irqchip: Add Loongson PCH PIC controller")
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Tested-by: Jiaxun Yang <jiaxun.yang@flygoat.com>
Link: https://lore.kernel.org/r/1596099090-23516-6-git-send-email-chenhc@lemote.com

drivers/irqchip/irq-loongson-pch-pic.c

@@ -64,15 +64,6 @@ static void pch_pic_bitclr(struct pch_pic *priv, int offset, int bit)
 	raw_spin_unlock(&priv->pic_lock);
 }
 
-static void pch_pic_eoi_irq(struct irq_data *d)
-{
-	u32 idx = PIC_REG_IDX(d->hwirq);
-	struct pch_pic *priv = irq_data_get_irq_chip_data(d);
-
-	writel(BIT(PIC_REG_BIT(d->hwirq)),
-			priv->base + PCH_PIC_CLR + idx * 4);
-}
-
 static void pch_pic_mask_irq(struct irq_data *d)
 {
 	struct pch_pic *priv = irq_data_get_irq_chip_data(d);
@@ -85,6 +76,9 @@ static void pch_pic_unmask_irq(struct irq_data *d)
 {
 	struct pch_pic *priv = irq_data_get_irq_chip_data(d);
 
+	writel(BIT(PIC_REG_BIT(d->hwirq)),
+			priv->base + PCH_PIC_CLR + PIC_REG_IDX(d->hwirq) * 4);
+
 	irq_chip_unmask_parent(d);
 	pch_pic_bitclr(priv, PCH_PIC_MASK, d->hwirq);
 }
@@ -124,7 +118,6 @@ static struct irq_chip pch_pic_irq_chip = {
 	.irq_mask		= pch_pic_mask_irq,
 	.irq_unmask		= pch_pic_unmask_irq,
 	.irq_ack		= irq_chip_ack_parent,
-	.irq_eoi		= pch_pic_eoi_irq,
 	.irq_set_affinity	= irq_chip_set_affinity_parent,
 	.irq_set_type		= pch_pic_set_type,
 };
@@ -153,7 +146,7 @@ static int pch_pic_alloc(struct irq_domain *domain, unsigned int virq,
 
 	irq_domain_set_info(domain, virq, hwirq,
 			    &pch_pic_irq_chip, priv,
-			    handle_fasteoi_ack_irq, NULL, NULL);
+			    handle_level_irq, NULL, NULL);
 	irq_set_probe(virq);
 
 	return 0;