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, 3 insertions, 3 deletions

diff --git a/arch/powerpc/sysdev/ppc4xx_hsta_msi.c b/arch/powerpc/sysdev/ppc4xx_hsta_msi.c
index 52a93dcae262..9926ad67af76 100644
--- a/arch/powerpc/sysdev/ppc4xx_hsta_msi.c
+++ b/arch/powerpc/sysdev/ppc4xx_hsta_msi.c
@@ -60,7 +60,7 @@ static int hsta_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 		}
 
 		hwirq = ppc4xx_hsta_msi.irq_map[irq];
-		if (hwirq == NO_IRQ) {
+		if (!hwirq) {
 			pr_err("%s: Failed mapping irq %d\n", __func__, irq);
 			return -EINVAL;
 		}
@@ -110,7 +110,7 @@ static void hsta_teardown_msi_irqs(struct pci_dev *dev)
 	int irq;
 
 	for_each_pci_msi_entry(entry, dev) {
-		if (entry->irq == NO_IRQ)
+		if (!entry->irq)
 			continue;
 
 		irq = hsta_find_hwirq_offset(entry->irq);
@@ -166,7 +166,7 @@ static int hsta_msi_probe(struct platform_device *pdev)
 	for (irq = 0; irq < irq_count; irq++) {
 		ppc4xx_hsta_msi.irq_map[irq] =
 			irq_of_parse_and_map(dev->of_node, irq);
-		if (ppc4xx_hsta_msi.irq_map[irq] == NO_IRQ) {
+		if (!ppc4xx_hsta_msi.irq_map[irq]) {
 			dev_err(dev, "Unable to map IRQ\n");
 			ret = -EINVAL;
 			goto out2;