irqchip/irq-vt8500: Split up ack/mask functions

vt8500_irq_mask() really does the ACK for edge triggered interrupts and the
MASK for level triggered interrupts.  Edge triggered interrupts never
really are masked as a result, and there is unnecessary reading of the
status register before the ACK even though it's write-one-to-clear.

Split it up into a proper standalone vt8500_irq_ack() and an unconditional
vt8500_irq_mask().

No Fixes tag added, as it has survived this way for 15 years and nobody
complained, so apparently nothing really used edge triggered interrupts
anyway.

[ tglx: Tabularize the irqchip struct initializer ]

Signed-off-by: Alexey Charkov <alchark@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250506-vt8500-intc-updates-v2-1-a3a0606cf92d@gmail.com

diff --git a/drivers/irqchip/irq-vt8500.c b/drivers/irqchip/irq-vt8500.c
index e17dd3a8c2d5a488fedfdea55de842177c314baa..9fb9d37c81e36bd594af23753cd1a70ab76ad14e 100644 (file)
--- a/drivers/irqchip/irq-vt8500.c
+++ b/drivers/irqchip/irq-vt8500.c
@@ -67,25 +67,25 @@ struct vt8500_irq_data {
 static struct vt8500_irq_data intc[VT8500_INTC_MAX];
 static u32 active_cnt = 0;
 
-static void vt8500_irq_mask(struct irq_data *d)
+static void vt8500_irq_ack(struct irq_data *d)
 {
        struct vt8500_irq_data *priv = d->domain->host_data;
        void __iomem *base = priv->base;
        void __iomem *stat_reg = base + VT8500_ICIS + (d->hwirq < 32 ? 0 : 4);
-       u8 edge, dctr;
-       u32 status;
-
-       edge = readb(base + VT8500_ICDC + d->hwirq) & VT8500_EDGE;
-       if (edge) {
-               status = readl(stat_reg);
-
-               status |= (1 << (d->hwirq & 0x1f));
-               writel(status, stat_reg);
-       } else {
-               dctr = readb(base + VT8500_ICDC + d->hwirq);
-               dctr &= ~VT8500_INT_ENABLE;
-               writeb(dctr, base + VT8500_ICDC + d->hwirq);
-       }
+       u32 status = (1 << (d->hwirq & 0x1f));
+
+       writel(status, stat_reg);
+}
+
+static void vt8500_irq_mask(struct irq_data *d)
+{
+       struct vt8500_irq_data *priv = d->domain->host_data;
+       void __iomem *base = priv->base;
+       u8 dctr;
+
+       dctr = readb(base + VT8500_ICDC + d->hwirq);
+       dctr &= ~VT8500_INT_ENABLE;
+       writeb(dctr, base + VT8500_ICDC + d->hwirq);
 }
 
 static void vt8500_irq_unmask(struct irq_data *d)
@@ -130,11 +130,11 @@ static int vt8500_irq_set_type(struct irq_data *d, unsigned int flow_type)
 }
 
 static struct irq_chip vt8500_irq_chip = {
-       .name = "vt8500",
-       .irq_ack = vt8500_irq_mask,
-       .irq_mask = vt8500_irq_mask,
-       .irq_unmask = vt8500_irq_unmask,
-       .irq_set_type = vt8500_irq_set_type,
+       .name           = "vt8500",
+       .irq_ack        = vt8500_irq_ack,
+       .irq_mask       = vt8500_irq_mask,
+       .irq_unmask     = vt8500_irq_unmask,
+       .irq_set_type   = vt8500_irq_set_type,
 };
 
 static void __init vt8500_init_irq_hw(void __iomem *base)