irqchip: sun4i: Don't ack IRQs > 0, fix acking of IRQ 0

All IRQs except for IRQ 0 seem to not need acking, so drop acking for them.

The ENMI needs to have the ack done *after* clearing the interrupt source,
otherwise we will get a spurious interrupt for each real interrupt.

So use the new IRQCHIP_EOI_THREADED flag for this in combination with
handle_fasteoi_irq. This uses a separate irq_chip struct for IRQ 0,
since we only want this behavior for IRQ 0.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-sunxi@googlegroups.com
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Link: http://lkml.kernel.org/r/1394733834-26839-5-git-send-email-hdegoede@redhat.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 16 insertions, 3 deletions

diff --git a/drivers/irqchip/irq-sun4i.c b/drivers/irqchip/irq-sun4i.c
index 60a28c69c65b..2029cc5e71c9 100644
--- a/drivers/irqchip/irq-sun4i.c
+++ b/drivers/irqchip/irq-sun4i.c
@@ -76,16 +76,29 @@ static void sun4i_irq_unmask(struct irq_data *irqd)
 
 static struct irq_chip sun4i_irq_chip = {
         .name           = "sun4i_irq",
-        .irq_ack        = sun4i_irq_ack,
         .irq_mask       = sun4i_irq_mask,
         .irq_unmask     = sun4i_irq_unmask,
 };
 
+/* IRQ 0 / the ENMI needs a late eoi call */
+static struct irq_chip sun4i_irq_chip_enmi = {
+        .name           = "sun4i_irq",
+        .irq_eoi        = sun4i_irq_ack,
+        .irq_mask       = sun4i_irq_mask,
+        .irq_unmask     = sun4i_irq_unmask,
+        .flags          = IRQCHIP_EOI_THREADED | IRQCHIP_EOI_IF_HANDLED,
+};
+
 static int sun4i_irq_map(struct irq_domain *d, unsigned int virq,
                          irq_hw_number_t hw)
 {
-        irq_set_chip_and_handler(virq, &sun4i_irq_chip,
-                                 handle_level_irq);
+        if (hw == 0)
+                irq_set_chip_and_handler(virq, &sun4i_irq_chip_enmi,
+                                         handle_fasteoi_irq);
+        else
+                irq_set_chip_and_handler(virq, &sun4i_irq_chip,
+                                         handle_level_irq);
+
         set_irq_flags(virq, IRQF_VALID | IRQF_PROBE);
 
         return 0;