powerpc: Remove all usages of NO_IRQ

NO_IRQ has been == 0 on powerpc for just over ten years (since commit
0ebfff1491ef ("[POWERPC] Add new interrupt mapping core and change
platforms to use it")). It's also 0 on most other arches.

Although it's fairly harmless, every now and then it causes confusion
when a driver is built on powerpc and another arch which doesn't define
NO_IRQ. There's at least 6 definitions of NO_IRQ in drivers/, at least
some of which are to work around that problem.

So we'd like to remove it. This is fairly trivial in the arch code, we
just convert:

    if (irq == NO_IRQ)	to	if (!irq)
    if (irq != NO_IRQ)	to	if (irq)
    irq = NO_IRQ;	to	irq = 0;
    return NO_IRQ;	to	return 0;

And a few other odd cases as well.

At least for now we keep the #define NO_IRQ, because there is driver
code that uses NO_IRQ and the fixes to remove those will go via other
trees.

Note we also change some occurrences in PPC sound drivers, drivers/ps3,
and drivers/macintosh.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

1 files changed, 7 insertions, 7 deletions

diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index 7de45b2df366..4d48cecfedd1 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -1649,7 +1649,7 @@ void __init mpic_init(struct mpic *mpic)
 	/* Check if this MPIC is chained from a parent interrupt controller */
 	if (mpic->flags & MPIC_SECONDARY) {
 		int virq = irq_of_parse_and_map(mpic->node, 0);
-		if (virq != NO_IRQ) {
+		if (virq) {
 			printk(KERN_INFO "%s: hooking up to IRQ %d\n",
 					mpic->node->full_name, virq);
 			irq_set_handler_data(virq, mpic);
@@ -1778,13 +1778,13 @@ static unsigned int _mpic_get_one_irq(struct mpic *mpic, int reg)
 	if (unlikely(src == mpic->spurious_vec)) {
 		if (mpic->flags & MPIC_SPV_EOI)
 			mpic_eoi(mpic);
-		return NO_IRQ;
+		return 0;
 	}
 	if (unlikely(mpic->protected && test_bit(src, mpic->protected))) {
 		printk_ratelimited(KERN_WARNING "%s: Got protected source %d !\n",
 				   mpic->name, (int)src);
 		mpic_eoi(mpic);
-		return NO_IRQ;
+		return 0;
 	}
 
 	return irq_linear_revmap(mpic->irqhost, src);
@@ -1817,17 +1817,17 @@ unsigned int mpic_get_coreint_irq(void)
 	if (unlikely(src == mpic->spurious_vec)) {
 		if (mpic->flags & MPIC_SPV_EOI)
 			mpic_eoi(mpic);
-		return NO_IRQ;
+		return 0;
 	}
 	if (unlikely(mpic->protected && test_bit(src, mpic->protected))) {
 		printk_ratelimited(KERN_WARNING "%s: Got protected source %d !\n",
 				   mpic->name, (int)src);
-		return NO_IRQ;
+		return 0;
 	}
 
 	return irq_linear_revmap(mpic->irqhost, src);
 #else
-	return NO_IRQ;
+	return 0;
 #endif
 }
 
@@ -1852,7 +1852,7 @@ void mpic_request_ipis(void)
 	for (i = 0; i < 4; i++) {
 		unsigned int vipi = irq_create_mapping(mpic->irqhost,
 						       mpic->ipi_vecs[0] + i);
-		if (vipi == NO_IRQ) {
+		if (!vipi) {
 			printk(KERN_ERR "Failed to map %s\n", smp_ipi_name[i]);
 			continue;
 		}