s390/irq: use irq 0

Irq 0 is currently unused on s390. Since there is no reason to
do this start counting at the beginning and gain an additional
irq. Also correctly report the smallest usable irq number for
dynamic allocation.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 1 insertions, 4 deletions

diff --git a/arch/s390/kernel/irq.c b/arch/s390/kernel/irq.c
index 1b8a38ab7861..f238720690f3 100644
--- a/arch/s390/kernel/irq.c
+++ b/arch/s390/kernel/irq.c
@@ -127,13 +127,10 @@ int show_interrupts(struct seq_file *p, void *v)
                 for_each_online_cpu(cpu)
                         seq_printf(p, "CPU%d       ", cpu);
                 seq_putc(p, '\n');
-                goto out;
         }
         if (index < NR_IRQS) {
                 if (index >= NR_IRQS_BASE)
                         goto out;
-                /* Adjust index to process irqclass_main_desc array entries */
-                index--;
                 seq_printf(p, "%s: ", irqclass_main_desc[index].name);
                 irq = irqclass_main_desc[index].irq;
                 for_each_online_cpu(cpu)
@@ -158,7 +155,7 @@ out:
 
 unsigned int arch_dynirq_lower_bound(unsigned int from)
 {
-        return from < THIN_INTERRUPT ? THIN_INTERRUPT : from;
+        return from < NR_IRQS_BASE ? NR_IRQS_BASE : from;
 }
 
 /*