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>

3 files changed, 8 insertions, 8 deletions

diff --git a/arch/powerpc/platforms/powermac/low_i2c.c b/arch/powerpc/platforms/powermac/low_i2c.c
index 6d6f277477aa..c8c217b7dd33 100644
--- a/arch/powerpc/platforms/powermac/low_i2c.c
+++ b/arch/powerpc/platforms/powermac/low_i2c.c
@@ -401,7 +401,7 @@ static int kw_i2c_xfer(struct pmac_i2c_bus *bus, u8 addrdir, int subsize,
 {
 	struct pmac_i2c_host_kw *host = bus->hostdata;
 	u8 mode_reg = host->speed;
-	int use_irq = host->irq != NO_IRQ && !bus->polled;
+	int use_irq = host->irq && !bus->polled;
 
 	/* Setup mode & subaddress if any */
 	switch(bus->mode) {
@@ -535,7 +535,7 @@ static struct pmac_i2c_host_kw *__init kw_i2c_host_init(struct device_node *np)
 		break;
 	}	
 	host->irq = irq_of_parse_and_map(np, 0);
-	if (host->irq == NO_IRQ)
+	if (!host->irq)
 		printk(KERN_WARNING
 		       "low_i2c: Failed to map interrupt for %s\n",
 		       np->full_name);
@@ -557,7 +557,7 @@ static struct pmac_i2c_host_kw *__init kw_i2c_host_init(struct device_node *np)
 	 */
 	if (request_irq(host->irq, kw_i2c_irq, IRQF_NO_SUSPEND,
 			"keywest i2c", host))
-		host->irq = NO_IRQ;
+		host->irq = 0;
 
 	printk(KERN_INFO "KeyWest i2c @0x%08x irq %d %s\n",
 	       *addrp, host->irq, np->full_name);
diff --git a/arch/powerpc/platforms/powermac/pfunc_base.c b/arch/powerpc/platforms/powermac/pfunc_base.c
index e49d07f3d542..459138ed4571 100644
--- a/arch/powerpc/platforms/powermac/pfunc_base.c
+++ b/arch/powerpc/platforms/powermac/pfunc_base.c
@@ -26,7 +26,7 @@ static irqreturn_t macio_gpio_irq(int irq, void *data)
 static int macio_do_gpio_irq_enable(struct pmf_function *func)
 {
 	unsigned int irq = irq_of_parse_and_map(func->node, 0);
-	if (irq == NO_IRQ)
+	if (!irq)
 		return -EINVAL;
 	return request_irq(irq, macio_gpio_irq, 0, func->node->name, func);
 }
@@ -34,7 +34,7 @@ static int macio_do_gpio_irq_enable(struct pmf_function *func)
 static int macio_do_gpio_irq_disable(struct pmf_function *func)
 {
 	unsigned int irq = irq_of_parse_and_map(func->node, 0);
-	if (irq == NO_IRQ)
+	if (!irq)
 		return -EINVAL;
 	free_irq(irq, func);
 	return 0;
diff --git a/arch/powerpc/platforms/powermac/pic.c b/arch/powerpc/platforms/powermac/pic.c
index 981546345033..f5f9ad7c3398 100644
--- a/arch/powerpc/platforms/powermac/pic.c
+++ b/arch/powerpc/platforms/powermac/pic.c
@@ -251,7 +251,7 @@ static unsigned int pmac_pic_get_irq(void)
 	}
 	raw_spin_unlock_irqrestore(&pmac_pic_lock, flags);
 	if (unlikely(irq < 0))
-		return NO_IRQ;
+		return 0;
 	return irq_linear_revmap(pmac_pic_host, irq);
 }
 
@@ -389,7 +389,7 @@ static void __init pmac_pic_probe_oldstyle(void)
 		out_le32(&pmac_irq_hw[i]->enable, 0);
 
 	/* Hookup cascade irq */
-	if (slave && pmac_irq_cascade != NO_IRQ)
+	if (slave && pmac_irq_cascade)
 		setup_irq(pmac_irq_cascade, &gatwick_cascade_action);
 
 	printk(KERN_INFO "irq: System has %d possible interrupts\n", max_irqs);
@@ -444,7 +444,7 @@ static void __init pmac_pic_setup_mpic_nmi(struct mpic *mpic)
 	pswitch = of_find_node_by_name(NULL, "programmer-switch");
 	if (pswitch) {
 		nmi_irq = irq_of_parse_and_map(pswitch, 0);
-		if (nmi_irq != NO_IRQ) {
+		if (nmi_irq) {
 			mpic_irq_set_priority(nmi_irq, 9);
 			setup_irq(nmi_irq, &xmon_action);
 		}