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>

7 files changed, 35 insertions, 32 deletions

diff --git a/arch/powerpc/platforms/cell/axon_msi.c b/arch/powerpc/platforms/cell/axon_msi.c
index aed7714495c1..8b55c5f19d4c 100644
--- a/arch/powerpc/platforms/cell/axon_msi.c
+++ b/arch/powerpc/platforms/cell/axon_msi.c
@@ -271,7 +271,7 @@ static int axon_msi_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
 
 	for_each_pci_msi_entry(entry, dev) {
 		virq = irq_create_direct_mapping(msic->irq_domain);
-		if (virq == NO_IRQ) {
+		if (!virq) {
 			dev_warn(&dev->dev,
 				 "axon_msi: virq allocation failed!\n");
 			return -1;
@@ -293,7 +293,7 @@ static void axon_msi_teardown_msi_irqs(struct pci_dev *dev)
 	dev_dbg(&dev->dev, "axon_msi: tearing down msi irqs\n");
 
 	for_each_pci_msi_entry(entry, dev) {
-		if (entry->irq == NO_IRQ)
+		if (!entry->irq)
 			continue;
 
 		irq_set_msi_desc(entry->irq, NULL);
@@ -375,7 +375,7 @@ static int axon_msi_probe(struct platform_device *device)
 	}
 
 	virq = irq_of_parse_and_map(dn, 0);
-	if (virq == NO_IRQ) {
+	if (!virq) {
 		printk(KERN_ERR "axon_msi: irq parse and map failed for %s\n",
 		       dn->full_name);
 		goto out_free_fifo;
diff --git a/arch/powerpc/platforms/cell/interrupt.c b/arch/powerpc/platforms/cell/interrupt.c
index 4d16b368b6f5..a6bbbaba14a3 100644
--- a/arch/powerpc/platforms/cell/interrupt.c
+++ b/arch/powerpc/platforms/cell/interrupt.c
@@ -123,7 +123,7 @@ static void iic_ioexc_cascade(struct irq_desc *desc)
 				unsigned int cirq =
 					irq_linear_revmap(iic_host,
 							  base | cascade);
-				if (cirq != NO_IRQ)
+				if (cirq)
 					generic_handle_irq(cirq);
 			}
 		/* post-ack level interrupts */
@@ -153,10 +153,10 @@ static unsigned int iic_get_irq(void)
 	*(unsigned long *) &pending =
 		in_be64((u64 __iomem *) &iic->regs->pending_destr);
 	if (!(pending.flags & CBE_IIC_IRQ_VALID))
-		return NO_IRQ;
+		return 0;
 	virq = irq_linear_revmap(iic_host, iic_pending_to_hwnum(pending));
-	if (virq == NO_IRQ)
-		return NO_IRQ;
+	if (!virq)
+		return 0;
 	iic->eoi_stack[++iic->eoi_ptr] = pending.prio;
 	BUG_ON(iic->eoi_ptr > 15);
 	return virq;
@@ -192,7 +192,7 @@ static void iic_request_ipi(int msg)
 	int virq;
 
 	virq = irq_create_mapping(iic_host, iic_msg_to_irq(msg));
-	if (virq == NO_IRQ) {
+	if (!virq) {
 		printk(KERN_ERR
 		       "iic: failed to map IPI %s\n", smp_ipi_name[msg]);
 		return;
@@ -347,7 +347,7 @@ static int __init setup_iic(void)
 		cascade |= 1 << IIC_IRQ_CLASS_SHIFT;
 		cascade |= IIC_UNIT_IIC;
 		cascade = irq_create_mapping(iic_host, cascade);
-		if (cascade == NO_IRQ)
+		if (!cascade)
 			continue;
 		/*
 		 * irq_data is a generic pointer that gets passed back
diff --git a/arch/powerpc/platforms/cell/iommu.c b/arch/powerpc/platforms/cell/iommu.c
index 640772af9bcb..7ff51f96a00e 100644
--- a/arch/powerpc/platforms/cell/iommu.c
+++ b/arch/powerpc/platforms/cell/iommu.c
@@ -411,7 +411,7 @@ static void cell_iommu_enable_hardware(struct cbe_iommu *iommu)
 
 	virq = irq_create_mapping(NULL,
 			IIC_IRQ_IOEX_ATI | (iommu->nid << IIC_IRQ_NODE_SHIFT));
-	BUG_ON(virq == NO_IRQ);
+	BUG_ON(!virq);
 
 	ret = request_irq(virq, ioc_interrupt, 0, iommu->name, iommu);
 	BUG_ON(ret);
diff --git a/arch/powerpc/platforms/cell/pmu.c b/arch/powerpc/platforms/cell/pmu.c
index 348a27b12512..e3ad0c38f017 100644
--- a/arch/powerpc/platforms/cell/pmu.c
+++ b/arch/powerpc/platforms/cell/pmu.c
@@ -385,7 +385,7 @@ static int __init cbe_init_pm_irq(void)
 	for_each_online_node(node) {
 		irq = irq_create_mapping(NULL, IIC_IRQ_IOEX_PMI |
 					       (node << IIC_IRQ_NODE_SHIFT));
-		if (irq == NO_IRQ) {
+		if (!irq) {
 			printk("ERROR: Unable to allocate irq for node %d\n",
 			       node);
 			return -EINVAL;
@@ -412,7 +412,7 @@ void cbe_sync_irq(int node)
 			       IIC_IRQ_IOEX_PMI
 			       | (node << IIC_IRQ_NODE_SHIFT));
 
-	if (irq == NO_IRQ) {
+	if (!irq) {
 		printk(KERN_WARNING "ERROR, unable to get existing irq %d " \
 		"for node %d\n", irq, node);
 		return;
diff --git a/arch/powerpc/platforms/cell/spider-pic.c b/arch/powerpc/platforms/cell/spider-pic.c
index d06dcac66fcb..ff924af00e78 100644
--- a/arch/powerpc/platforms/cell/spider-pic.c
+++ b/arch/powerpc/platforms/cell/spider-pic.c
@@ -207,11 +207,11 @@ static void spider_irq_cascade(struct irq_desc *desc)
 
 	cs = in_be32(pic->regs + TIR_CS) >> 24;
 	if (cs == SPIDER_IRQ_INVALID)
-		virq = NO_IRQ;
+		virq = 0;
 	else
 		virq = irq_linear_revmap(pic->host, cs);
 
-	if (virq != NO_IRQ)
+	if (virq)
 		generic_handle_irq(virq);
 
 	chip->irq_eoi(&desc->irq_data);
@@ -245,19 +245,19 @@ static unsigned int __init spider_find_cascade_and_node(struct spider_pic *pic)
 	/* Now do the horrible hacks */
 	tmp = of_get_property(of_node, "#interrupt-cells", NULL);
 	if (tmp == NULL)
-		return NO_IRQ;
+		return 0;
 	intsize = *tmp;
 	imap = of_get_property(of_node, "interrupt-map", &imaplen);
 	if (imap == NULL || imaplen < (intsize + 1))
-		return NO_IRQ;
+		return 0;
 	iic = of_find_node_by_phandle(imap[intsize]);
 	if (iic == NULL)
-		return NO_IRQ;
+		return 0;
 	imap += intsize + 1;
 	tmp = of_get_property(iic, "#interrupt-cells", NULL);
 	if (tmp == NULL) {
 		of_node_put(iic);
-		return NO_IRQ;
+		return 0;
 	}
 	intsize = *tmp;
 	/* Assume unit is last entry of interrupt specifier */
@@ -266,7 +266,7 @@ static unsigned int __init spider_find_cascade_and_node(struct spider_pic *pic)
 	tmp = of_get_property(iic, "ibm,interrupt-server-ranges", NULL);
 	if (tmp == NULL) {
 		of_node_put(iic);
-		return NO_IRQ;
+		return 0;
 	}
 	/* ugly as hell but works for now */
 	pic->node_id = (*tmp) >> 1;
@@ -281,7 +281,7 @@ static unsigned int __init spider_find_cascade_and_node(struct spider_pic *pic)
 				  (pic->node_id << IIC_IRQ_NODE_SHIFT) |
 				  (2 << IIC_IRQ_CLASS_SHIFT) |
 				  unit);
-	if (virq == NO_IRQ)
+	if (!virq)
 		printk(KERN_ERR "spider_pic: failed to map cascade !");
 	return virq;
 }
@@ -318,7 +318,7 @@ static void __init spider_init_one(struct device_node *of_node, int chip,
 
 	/* Hook up the cascade interrupt to the iic and nodeid */
 	virq = spider_find_cascade_and_node(pic);
-	if (virq == NO_IRQ)
+	if (!virq)
 		return;
 	irq_set_handler_data(virq, pic);
 	irq_set_chained_handler(virq, spider_irq_cascade);
diff --git a/arch/powerpc/platforms/cell/spu_base.c b/arch/powerpc/platforms/cell/spu_base.c
index bb4a8e07c229..e84d8fbc2e21 100644
--- a/arch/powerpc/platforms/cell/spu_base.c
+++ b/arch/powerpc/platforms/cell/spu_base.c
@@ -402,7 +402,7 @@ static int spu_request_irqs(struct spu *spu)
 {
 	int ret = 0;
 
-	if (spu->irqs[0] != NO_IRQ) {
+	if (spu->irqs[0]) {
 		snprintf(spu->irq_c0, sizeof (spu->irq_c0), "spe%02d.0",
 			 spu->number);
 		ret = request_irq(spu->irqs[0], spu_irq_class_0,
@@ -410,7 +410,7 @@ static int spu_request_irqs(struct spu *spu)
 		if (ret)
 			goto bail0;
 	}
-	if (spu->irqs[1] != NO_IRQ) {
+	if (spu->irqs[1]) {
 		snprintf(spu->irq_c1, sizeof (spu->irq_c1), "spe%02d.1",
 			 spu->number);
 		ret = request_irq(spu->irqs[1], spu_irq_class_1,
@@ -418,7 +418,7 @@ static int spu_request_irqs(struct spu *spu)
 		if (ret)
 			goto bail1;
 	}
-	if (spu->irqs[2] != NO_IRQ) {
+	if (spu->irqs[2]) {
 		snprintf(spu->irq_c2, sizeof (spu->irq_c2), "spe%02d.2",
 			 spu->number);
 		ret = request_irq(spu->irqs[2], spu_irq_class_2,
@@ -429,10 +429,10 @@ static int spu_request_irqs(struct spu *spu)
 	return 0;
 
 bail2:
-	if (spu->irqs[1] != NO_IRQ)
+	if (spu->irqs[1])
 		free_irq(spu->irqs[1], spu);
 bail1:
-	if (spu->irqs[0] != NO_IRQ)
+	if (spu->irqs[0])
 		free_irq(spu->irqs[0], spu);
 bail0:
 	return ret;
@@ -440,11 +440,11 @@ bail0:
 
 static void spu_free_irqs(struct spu *spu)
 {
-	if (spu->irqs[0] != NO_IRQ)
+	if (spu->irqs[0])
 		free_irq(spu->irqs[0], spu);
-	if (spu->irqs[1] != NO_IRQ)
+	if (spu->irqs[1])
 		free_irq(spu->irqs[1], spu);
-	if (spu->irqs[2] != NO_IRQ)
+	if (spu->irqs[2])
 		free_irq(spu->irqs[2], spu);
 }
 
diff --git a/arch/powerpc/platforms/cell/spu_manage.c b/arch/powerpc/platforms/cell/spu_manage.c
index 21b4bfb97200..672d310dcf14 100644
--- a/arch/powerpc/platforms/cell/spu_manage.c
+++ b/arch/powerpc/platforms/cell/spu_manage.c
@@ -105,7 +105,10 @@ static int __init spu_map_interrupts_old(struct spu *spu,
 	spu->irqs[2] = irq_create_mapping(NULL, IIC_IRQ_CLASS_2 | isrc);
 
 	/* Right now, we only fail if class 2 failed */
-	return spu->irqs[2] == NO_IRQ ? -EINVAL : 0;
+	if (!spu->irqs[2])
+		return -EINVAL;
+
+	return 0;
 }
 
 static void __iomem * __init spu_map_prop_old(struct spu *spu,
@@ -191,7 +194,7 @@ static int __init spu_map_interrupts(struct spu *spu, struct device_node *np)
 		pr_debug("  irq %d no 0x%x on %s\n", i, oirq.args[0],
 			 oirq.np->full_name);
 		spu->irqs[i] = irq_create_of_mapping(&oirq);
-		if (spu->irqs[i] == NO_IRQ) {
+		if (!spu->irqs[i]) {
 			pr_debug("spu_new: failed to map it !\n");
 			goto err;
 		}
@@ -202,7 +205,7 @@ err:
 	pr_debug("failed to map irq %x for spu %s\n", *oirq.args,
 		spu->name);
 	for (; i >= 0; i--) {
-		if (spu->irqs[i] != NO_IRQ)
+		if (spu->irqs[i])
 			irq_dispose_mapping(spu->irqs[i]);
 	}
 	return ret;