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>

5 files changed, 13 insertions, 12 deletions

diff --git a/arch/powerpc/kernel/ibmebus.c b/arch/powerpc/kernel/ibmebus.c
index c1ca9282f4a0..6ca9a2ffaac7 100644
--- a/arch/powerpc/kernel/ibmebus.c
+++ b/arch/powerpc/kernel/ibmebus.c
@@ -227,7 +227,7 @@ int ibmebus_request_irq(u32 ist, irq_handler_t handler,
 {
 	unsigned int irq = irq_create_mapping(NULL, ist);
 
-	if (irq == NO_IRQ)
+	if (!irq)
 		return -EINVAL;
 
 	return request_irq(irq, handler, irq_flags, devname, dev_id);
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index 471f65ad1b9b..3c05c311e35e 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -519,7 +519,7 @@ void __do_irq(struct pt_regs *regs)
 	may_hard_irq_enable();
 
 	/* And finally process it */
-	if (unlikely(irq == NO_IRQ))
+	if (unlikely(!irq))
 		__this_cpu_inc(irq_stat.spurious_irqs);
 	else
 		generic_handle_irq(irq);
diff --git a/arch/powerpc/kernel/legacy_serial.c b/arch/powerpc/kernel/legacy_serial.c
index 7b750c4ed5c7..bc525ea0dc09 100644
--- a/arch/powerpc/kernel/legacy_serial.c
+++ b/arch/powerpc/kernel/legacy_serial.c
@@ -193,10 +193,10 @@ static int __init add_legacy_soc_port(struct device_node *np,
 	 */
 	if (tsi && !strcmp(tsi->type, "tsi-bridge"))
 		return add_legacy_port(np, -1, UPIO_TSI, addr, addr,
-				       NO_IRQ, legacy_port_flags, 0);
+				       0, legacy_port_flags, 0);
 	else
 		return add_legacy_port(np, -1, UPIO_MEM, addr, addr,
-				       NO_IRQ, legacy_port_flags, 0);
+				       0, legacy_port_flags, 0);
 }
 
 static int __init add_legacy_isa_port(struct device_node *np,
@@ -242,7 +242,7 @@ static int __init add_legacy_isa_port(struct device_node *np,
 
 	/* Add port, irq will be dealt with later */
 	return add_legacy_port(np, index, UPIO_PORT, be32_to_cpu(reg[1]),
-			       taddr, NO_IRQ, legacy_port_flags, 0);
+			       taddr, 0, legacy_port_flags, 0);
 
 }
 
@@ -314,7 +314,7 @@ static int __init add_legacy_pci_port(struct device_node *np,
 	/* Add port, irq will be dealt with later. We passed a translated
 	 * IO port value. It will be fixed up later along with the irq
 	 */
-	return add_legacy_port(np, index, iotype, base, addr, NO_IRQ,
+	return add_legacy_port(np, index, iotype, base, addr, 0,
 			       legacy_port_flags, np != pci_dev);
 }
 #endif
@@ -462,14 +462,14 @@ static void __init fixup_port_irq(int index,
 	DBG("fixup_port_irq(%d)\n", index);
 
 	virq = irq_of_parse_and_map(np, 0);
-	if (virq == NO_IRQ && legacy_serial_infos[index].irq_check_parent) {
+	if (!virq && legacy_serial_infos[index].irq_check_parent) {
 		np = of_get_parent(np);
 		if (np == NULL)
 			return;
 		virq = irq_of_parse_and_map(np, 0);
 		of_node_put(np);
 	}
-	if (virq == NO_IRQ)
+	if (!virq)
 		return;
 
 	port->irq = virq;
@@ -543,7 +543,7 @@ static int __init serial_dev_init(void)
 		struct plat_serial8250_port *port = &legacy_serial_ports[i];
 		struct device_node *np = legacy_serial_infos[i].np;
 
-		if (port->irq == NO_IRQ)
+		if (!port->irq)
 			fixup_port_irq(i, np, port);
 		if (port->iotype == UPIO_PORT)
 			fixup_port_pio(i, np, port);
diff --git a/arch/powerpc/kernel/pci-common.c b/arch/powerpc/kernel/pci-common.c
index e58908066b0e..95d3769a2e26 100644
--- a/arch/powerpc/kernel/pci-common.c
+++ b/arch/powerpc/kernel/pci-common.c
@@ -360,7 +360,7 @@ static int pci_read_irq_line(struct pci_dev *pci_dev)
 			 line, pin);
 
 		virq = irq_create_mapping(NULL, line);
-		if (virq != NO_IRQ)
+		if (virq)
 			irq_set_irq_type(virq, IRQ_TYPE_LEVEL_LOW);
 	} else {
 		pr_debug(" Got one, spec %d cells (0x%08x 0x%08x...) on %s\n",
@@ -369,7 +369,8 @@ static int pci_read_irq_line(struct pci_dev *pci_dev)
 
 		virq = irq_create_of_mapping(&oirq);
 	}
-	if(virq == NO_IRQ) {
+
+	if (!virq) {
 		pr_debug(" Failed to map !\n");
 		return -1;
 	}
diff --git a/arch/powerpc/kernel/pci_of_scan.c b/arch/powerpc/kernel/pci_of_scan.c
index 526ac6750e4d..ea3d98115b88 100644
--- a/arch/powerpc/kernel/pci_of_scan.c
+++ b/arch/powerpc/kernel/pci_of_scan.c
@@ -178,7 +178,7 @@ struct pci_dev *of_create_pci_dev(struct device_node *node,
 		dev->hdr_type = PCI_HEADER_TYPE_NORMAL;
 		dev->rom_base_reg = PCI_ROM_ADDRESS;
 		/* Maybe do a default OF mapping here */
-		dev->irq = NO_IRQ;
+		dev->irq = 0;
 	}
 
 	of_pci_parse_addrs(node, dev);