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>

80 files changed, 204 insertions, 200 deletions

diff --git a/arch/powerpc/include/asm/machdep.h b/arch/powerpc/include/asm/machdep.h
index 0420b388dd83..e02cbc6a6c70 100644
--- a/arch/powerpc/include/asm/machdep.h
+++ b/arch/powerpc/include/asm/machdep.h
@@ -61,7 +61,7 @@ struct machdep_calls {
 
         void            (*init_IRQ)(void);
 
-        /* Return an irq, or NO_IRQ to indicate there are none pending. */
+        /* Return an irq, or 0 to indicate there are none pending. */
         unsigned int    (*get_irq)(void);
 
         /* PCI stuff */
diff --git a/arch/powerpc/include/asm/mpic_msgr.h b/arch/powerpc/include/asm/mpic_msgr.h
index d4f471fb1031..088420d8aa59 100644
--- a/arch/powerpc/include/asm/mpic_msgr.h
+++ b/arch/powerpc/include/asm/mpic_msgr.h
@@ -122,9 +122,9 @@ static inline void mpic_msgr_set_destination(struct mpic_msgr *msgr,
  * @msgr:       the message register whose IRQ is to be returned
  *
  * Returns the IRQ number associated with the given message register.
- * NO_IRQ is returned if this message register is not capable of
- * receiving interrupts.  What message register can and cannot receive
- * interrupts is specified in the device tree for the system.
+ * 0 is returned if this message register is not capable of receiving
+ * interrupts.  What message register can and cannot receive interrupts is
+ * specified in the device tree for the system.
  */
 static inline int mpic_msgr_get_irq(struct mpic_msgr *msgr)
 {
diff --git a/arch/powerpc/include/asm/parport.h b/arch/powerpc/include/asm/parport.h
index a452968b29ea..6595ad1d18cc 100644
--- a/arch/powerpc/include/asm/parport.h
+++ b/arch/powerpc/include/asm/parport.h
@@ -28,7 +28,7 @@ static int parport_pc_find_nonpci_ports (int autoirq, int autodma)
                 io1 = prop[1]; io2 = prop[2];
 
                 virq = irq_of_parse_and_map(np, 0);
-                if (virq == NO_IRQ)
+                if (!virq)
                         continue;
 
                 if (parport_pc_probe_port(io1, io2, virq, autodma, NULL, 0)
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);
diff --git a/arch/powerpc/platforms/44x/warp.c b/arch/powerpc/platforms/44x/warp.c
index 5ecce543103e..a886c2c22097 100644
--- a/arch/powerpc/platforms/44x/warp.c
+++ b/arch/powerpc/platforms/44x/warp.c
@@ -204,7 +204,7 @@ static void pika_setup_critical_temp(struct device_node *np,
         i2c_smbus_write_byte_data(client, 3,  0); /* Tlow */
 
         irq = irq_of_parse_and_map(np, 0);
-        if (irq  == NO_IRQ) {
+        if (!irq) {
                 printk(KERN_ERR __FILE__ ": Unable to get ad7414 irq\n");
                 return;
         }
diff --git a/arch/powerpc/platforms/512x/mpc5121_ads_cpld.c b/arch/powerpc/platforms/512x/mpc5121_ads_cpld.c
index 0035d146df73..fe4d4eac7427 100644
--- a/arch/powerpc/platforms/512x/mpc5121_ads_cpld.c
+++ b/arch/powerpc/platforms/512x/mpc5121_ads_cpld.c
@@ -97,7 +97,7 @@ cpld_pic_get_irq(int offset, u8 ignore, u8 __iomem *statusp,
         status |= (ignore | mask);
 
         if (status == 0xff)
-                return NO_IRQ;
+                return 0;
 
         cpld_irq = ffz(status) + offset;
 
@@ -110,14 +110,14 @@ static void cpld_pic_cascade(struct irq_desc *desc)
 
         irq = cpld_pic_get_irq(0, PCI_IGNORE, &cpld_regs->pci_status,
                 &cpld_regs->pci_mask);
-        if (irq != NO_IRQ) {
+        if (irq) {
                 generic_handle_irq(irq);
                 return;
         }
 
         irq = cpld_pic_get_irq(8, MISC_IGNORE, &cpld_regs->misc_status,
                 &cpld_regs->misc_mask);
-        if (irq != NO_IRQ) {
+        if (irq) {
                 generic_handle_irq(irq);
                 return;
         }
@@ -177,7 +177,7 @@ mpc5121_ads_cpld_pic_init(void)
                 goto end;
 
         cascade_irq = irq_of_parse_and_map(np, 0);
-        if (cascade_irq == NO_IRQ)
+        if (!cascade_irq)
                 goto end;
 
         /*
diff --git a/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c b/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c
index d93dd4acf40b..cec3f88f153d 100644
--- a/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c
+++ b/arch/powerpc/platforms/512x/mpc512x_lpbfifo.c
@@ -473,7 +473,7 @@ static int mpc512x_lpbfifo_probe(struct platform_device *pdev)
         }
 
         lpbfifo.irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
-        if (lpbfifo.irq == NO_IRQ) {
+        if (!lpbfifo.irq) {
                 dev_err(&pdev->dev, "mapping irq failed\n");
                 ret = -ENODEV;
                 goto err0;
diff --git a/arch/powerpc/platforms/52xx/mpc52xx_pic.c b/arch/powerpc/platforms/52xx/mpc52xx_pic.c
index 4fe2074c88cb..fc98912f42cf 100644
--- a/arch/powerpc/platforms/52xx/mpc52xx_pic.c
+++ b/arch/powerpc/platforms/52xx/mpc52xx_pic.c
@@ -511,7 +511,7 @@ unsigned int mpc52xx_get_irq(void)
                         irq |= (MPC52xx_IRQ_L1_PERP << MPC52xx_IRQ_L1_OFFSET);
                 }
         } else {
-                return NO_IRQ;
+                return 0;
         }
 
         return irq_linear_revmap(mpc52xx_irqhost, irq);
diff --git a/arch/powerpc/platforms/82xx/pq2ads-pci-pic.c b/arch/powerpc/platforms/82xx/pq2ads-pci-pic.c
index 60e89fc9c753..8b065bdf7412 100644
--- a/arch/powerpc/platforms/82xx/pq2ads-pci-pic.c
+++ b/arch/powerpc/platforms/82xx/pq2ads-pci-pic.c
@@ -131,7 +131,7 @@ int __init pq2ads_pci_init_irq(void)
         }
 
         irq = irq_of_parse_and_map(np, 0);
-        if (irq == NO_IRQ) {
+        if (!irq) {
                 printk(KERN_ERR "No interrupt in pci pic node.\n");
                 of_node_put(np);
                 goto out;
diff --git a/arch/powerpc/platforms/83xx/mpc832x_rdb.c b/arch/powerpc/platforms/83xx/mpc832x_rdb.c
index 2ef03e7d248c..0d6a62fc5864 100644
--- a/arch/powerpc/platforms/83xx/mpc832x_rdb.c
+++ b/arch/powerpc/platforms/83xx/mpc832x_rdb.c
@@ -89,7 +89,7 @@ static int __init of_fsl_spi_probe(char *type, char *compatible, u32 sysclk,
                         goto err;
 
                 ret = of_irq_to_resource(np, 0, &res[1]);
-                if (ret == NO_IRQ)
+                if (!ret)
                         goto err;
 
                 pdev = platform_device_alloc("mpc83xx_spi", i);
diff --git a/arch/powerpc/platforms/83xx/suspend.c b/arch/powerpc/platforms/83xx/suspend.c
index fcbea4b51a78..24717d060008 100644
--- a/arch/powerpc/platforms/83xx/suspend.c
+++ b/arch/powerpc/platforms/83xx/suspend.c
@@ -352,7 +352,7 @@ static int pmc_probe(struct platform_device *ofdev)
                 return -ENODEV;
 
         pmc_irq = irq_of_parse_and_map(np, 0);
-        if (pmc_irq != NO_IRQ) {
+        if (pmc_irq) {
                 ret = request_irq(pmc_irq, pmc_irq_handler, IRQF_SHARED,
                                   "pmc", ofdev);
 
@@ -400,7 +400,7 @@ out_syscr:
 out_pmc:
         iounmap(pmc_regs);
 out:
-        if (pmc_irq != NO_IRQ)
+        if (pmc_irq)
                 free_irq(pmc_irq, ofdev);
 
         return ret;
diff --git a/arch/powerpc/platforms/85xx/common.c b/arch/powerpc/platforms/85xx/common.c
index 28720a4ded7b..954e5e8b14ef 100644
--- a/arch/powerpc/platforms/85xx/common.c
+++ b/arch/powerpc/platforms/85xx/common.c
@@ -76,7 +76,7 @@ void __init mpc85xx_cpm2_pic_init(void)
                 return;
         }
         irq = irq_of_parse_and_map(np, 0);
-        if (irq == NO_IRQ) {
+        if (!irq) {
                 of_node_put(np);
                 printk(KERN_ERR "PIC init: got no IRQ for cpm cascade\n");
                 return;
diff --git a/arch/powerpc/platforms/85xx/mpc85xx_cds.c b/arch/powerpc/platforms/85xx/mpc85xx_cds.c
index 62f171c71c4c..86f20156178e 100644
--- a/arch/powerpc/platforms/85xx/mpc85xx_cds.c
+++ b/arch/powerpc/platforms/85xx/mpc85xx_cds.c
@@ -196,7 +196,7 @@ static void mpc85xx_8259_cascade_handler(struct irq_desc *desc)
 {
         unsigned int cascade_irq = i8259_irq();
 
-        if (cascade_irq != NO_IRQ)
+        if (cascade_irq)
                 /* handle an interrupt from the 8259 */
                 generic_handle_irq(cascade_irq);
 
@@ -247,7 +247,7 @@ static int mpc85xx_cds_8259_attach(void)
         }
 
         cascade_irq = irq_of_parse_and_map(cascade_node, 0);
-        if (cascade_irq == NO_IRQ) {
+        if (!cascade_irq) {
                 printk(KERN_ERR "Failed to map cascade interrupt\n");
                 return -ENXIO;
         }
diff --git a/arch/powerpc/platforms/85xx/mpc85xx_ds.c b/arch/powerpc/platforms/85xx/mpc85xx_ds.c
index 6bc07d837b1c..ed69c7ee1829 100644
--- a/arch/powerpc/platforms/85xx/mpc85xx_ds.c
+++ b/arch/powerpc/platforms/85xx/mpc85xx_ds.c
@@ -51,7 +51,7 @@ static void mpc85xx_8259_cascade(struct irq_desc *desc)
         struct irq_chip *chip = irq_desc_get_chip(desc);
         unsigned int cascade_irq = i8259_irq();
 
-        if (cascade_irq != NO_IRQ) {
+        if (cascade_irq) {
                 generic_handle_irq(cascade_irq);
         }
         chip->irq_eoi(&desc->irq_data);
@@ -96,7 +96,7 @@ void __init mpc85xx_ds_pic_init(void)
         }
 
         cascade_irq = irq_of_parse_and_map(cascade_node, 0);
-        if (cascade_irq == NO_IRQ) {
+        if (!cascade_irq) {
                 printk(KERN_ERR "Failed to map cascade interrupt\n");
                 return;
         }
diff --git a/arch/powerpc/platforms/85xx/socrates_fpga_pic.c b/arch/powerpc/platforms/85xx/socrates_fpga_pic.c
index b02d6a5bb035..82f8490b5aa7 100644
--- a/arch/powerpc/platforms/85xx/socrates_fpga_pic.c
+++ b/arch/powerpc/platforms/85xx/socrates_fpga_pic.c
@@ -78,7 +78,7 @@ static inline unsigned int socrates_fpga_pic_get_irq(unsigned int irq)
                         break;
         }
         if (i == 3)
-                return NO_IRQ;
+                return 0;
 
         raw_spin_lock_irqsave(&socrates_fpga_pic_lock, flags);
         cause = socrates_fpga_pic_read(FPGA_PIC_IRQMASK(i));
@@ -103,7 +103,7 @@ static void socrates_fpga_pic_cascade(struct irq_desc *desc)
          */
         cascade_irq = socrates_fpga_pic_get_irq(irq);
 
-        if (cascade_irq != NO_IRQ)
+        if (cascade_irq)
                 generic_handle_irq(cascade_irq);
         chip->irq_eoi(&desc->irq_data);
 }
@@ -292,7 +292,7 @@ void socrates_fpga_pic_init(struct device_node *pic)
 
         for (i = 0; i < 3; i++) {
                 socrates_fpga_irqs[i] = irq_of_parse_and_map(pic, i);
-                if (socrates_fpga_irqs[i] == NO_IRQ) {
+                if (!socrates_fpga_irqs[i]) {
                         pr_warning("FPGA PIC: can't get irq%d.\n", i);
                         continue;
                 }
diff --git a/arch/powerpc/platforms/86xx/pic.c b/arch/powerpc/platforms/86xx/pic.c
index 845defa1fd19..a6c695fa4da0 100644
--- a/arch/powerpc/platforms/86xx/pic.c
+++ b/arch/powerpc/platforms/86xx/pic.c
@@ -22,7 +22,7 @@ static void mpc86xx_8259_cascade(struct irq_desc *desc)
         struct irq_chip *chip = irq_desc_get_chip(desc);
         unsigned int cascade_irq = i8259_irq();
 
-        if (cascade_irq != NO_IRQ)
+        if (cascade_irq)
                 generic_handle_irq(cascade_irq);
 
         chip->irq_eoi(&desc->irq_data);
@@ -58,7 +58,7 @@ void __init mpc86xx_init_irq(void)
         }
 
         cascade_irq = irq_of_parse_and_map(cascade_node, 0);
-        if (cascade_irq == NO_IRQ) {
+        if (!cascade_irq) {
                 printk(KERN_ERR "Failed to map cascade interrupt\n");
                 return;
         }
diff --git a/arch/powerpc/platforms/8xx/m8xx_setup.c b/arch/powerpc/platforms/8xx/m8xx_setup.c
index b1ab6e96cb31..f81069f79a94 100644
--- a/arch/powerpc/platforms/8xx/m8xx_setup.c
+++ b/arch/powerpc/platforms/8xx/m8xx_setup.c
@@ -241,6 +241,6 @@ void __init mpc8xx_pics_init(void)
         }
 
         irq = cpm_pic_init();
-        if (irq != NO_IRQ)
+        if (irq)
                 irq_set_chained_handler(irq, cpm_cascade);
 }
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;
diff --git a/arch/powerpc/platforms/chrp/setup.c b/arch/powerpc/platforms/chrp/setup.c
index bfb300633dfe..0ce1b45f02a8 100644
--- a/arch/powerpc/platforms/chrp/setup.c
+++ b/arch/powerpc/platforms/chrp/setup.c
@@ -368,7 +368,7 @@ static void chrp_8259_cascade(struct irq_desc *desc)
         struct irq_chip *chip = irq_desc_get_chip(desc);
         unsigned int cascade_irq = i8259_irq();
 
-        if (cascade_irq != NO_IRQ)
+        if (cascade_irq)
                 generic_handle_irq(cascade_irq);
 
         chip->irq_eoi(&desc->irq_data);
@@ -514,7 +514,7 @@ static void __init chrp_find_8259(void)
         }
         if (chrp_mpic != NULL) {
                 cascade_irq = irq_of_parse_and_map(pic, 0);
-                if (cascade_irq == NO_IRQ)
+                if (!cascade_irq)
                         printk(KERN_ERR "i8259: failed to map cascade irq\n");
                 else
                         irq_set_chained_handler(cascade_irq,
diff --git a/arch/powerpc/platforms/embedded6xx/flipper-pic.c b/arch/powerpc/platforms/embedded6xx/flipper-pic.c
index b7866e01483d..ade83829d5e8 100644
--- a/arch/powerpc/platforms/embedded6xx/flipper-pic.c
+++ b/arch/powerpc/platforms/embedded6xx/flipper-pic.c
@@ -181,7 +181,7 @@ unsigned int flipper_pic_get_irq(void)
         irq_status = in_be32(io_base + FLIPPER_ICR) &
                      in_be32(io_base + FLIPPER_IMR);
         if (irq_status == 0)
-                return NO_IRQ;  /* no more IRQs pending */
+                return 0;       /* no more IRQs pending */
 
         irq = __ffs(irq_status);
         return irq_linear_revmap(flipper_irq_host, irq);
diff --git a/arch/powerpc/platforms/embedded6xx/hlwd-pic.c b/arch/powerpc/platforms/embedded6xx/hlwd-pic.c
index 9b7975706bfc..89c54de88b7a 100644
--- a/arch/powerpc/platforms/embedded6xx/hlwd-pic.c
+++ b/arch/powerpc/platforms/embedded6xx/hlwd-pic.c
@@ -114,7 +114,7 @@ static unsigned int __hlwd_pic_get_irq(struct irq_domain *h)
         irq_status = in_be32(io_base + HW_BROADWAY_ICR) &
                      in_be32(io_base + HW_BROADWAY_IMR);
         if (irq_status == 0)
-                return NO_IRQ;  /* no more IRQs pending */
+                return 0;       /* no more IRQs pending */
 
         irq = __ffs(irq_status);
         return irq_linear_revmap(h, irq);
@@ -131,7 +131,7 @@ static void hlwd_pic_irq_cascade(struct irq_desc *desc)
         raw_spin_unlock(&desc->lock);
 
         virq = __hlwd_pic_get_irq(irq_domain);
-        if (virq != NO_IRQ)
+        if (virq)
                 generic_handle_irq(virq);
         else
                 pr_err("spurious interrupt!\n");
diff --git a/arch/powerpc/platforms/embedded6xx/mvme5100.c b/arch/powerpc/platforms/embedded6xx/mvme5100.c
index ed7321d6772e..8e3590941960 100644
--- a/arch/powerpc/platforms/embedded6xx/mvme5100.c
+++ b/arch/powerpc/platforms/embedded6xx/mvme5100.c
@@ -47,7 +47,7 @@ static void mvme5100_8259_cascade(struct irq_desc *desc)
         struct irq_chip *chip = irq_desc_get_chip(desc);
         unsigned int cascade_irq = i8259_irq();
 
-        if (cascade_irq != NO_IRQ)
+        if (cascade_irq)
                 generic_handle_irq(cascade_irq);
 
         chip->irq_eoi(&desc->irq_data);
@@ -84,7 +84,7 @@ static void __init mvme5100_pic_init(void)
         }
 
         cirq = irq_of_parse_and_map(cp, 0);
-        if (cirq == NO_IRQ) {
+        if (!cirq) {
                 pr_warn("mvme5100_pic_init: no cascade interrupt?\n");
                 return;
         }
diff --git a/arch/powerpc/platforms/maple/pci.c b/arch/powerpc/platforms/maple/pci.c
index a2f89e6326ce..a0589aac4163 100644
--- a/arch/powerpc/platforms/maple/pci.c
+++ b/arch/powerpc/platforms/maple/pci.c
@@ -552,7 +552,7 @@ void maple_pci_irq_fixup(struct pci_dev *dev)
             pci_bus_to_host(dev->bus) == u4_pcie) {
                 printk(KERN_DEBUG "Fixup U4 PCIe IRQ\n");
                 dev->irq = irq_create_mapping(NULL, 1);
-                if (dev->irq != NO_IRQ)
+                if (dev->irq)
                         irq_set_irq_type(dev->irq, IRQ_TYPE_LEVEL_LOW);
         }
 
@@ -562,7 +562,7 @@ void maple_pci_irq_fixup(struct pci_dev *dev)
         if (dev->vendor == PCI_VENDOR_ID_AMD &&
             dev->device == PCI_DEVICE_ID_AMD_8111_IDE &&
             (dev->class & 5) != 5) {
-                dev->irq = NO_IRQ;
+                dev->irq = 0;
         }
 
         DBG(" <- maple_pci_irq_fixup\n");
@@ -648,7 +648,7 @@ int maple_pci_get_legacy_ide_irq(struct pci_dev *pdev, int channel)
                 return defirq;
         }
         irq = irq_of_parse_and_map(np, channel & 0x1);
-        if (irq == NO_IRQ) {
+        if (!irq) {
                 printk("Failed to map onboard IDE interrupt for channel %d\n",
                        channel);
                 return defirq;
diff --git a/arch/powerpc/platforms/pasemi/misc.c b/arch/powerpc/platforms/pasemi/misc.c
index e0ab299763c1..8571e7bf78b6 100644
--- a/arch/powerpc/platforms/pasemi/misc.c
+++ b/arch/powerpc/platforms/pasemi/misc.c
@@ -76,7 +76,7 @@ static int __init pasemi_register_i2c_devices(void)
                         }
 
                         info.irq = irq_of_parse_and_map(node, 0);
-                        if (info.irq == NO_IRQ)
+                        if (!info.irq)
                                 info.irq = -1;
 
                         if (find_i2c_driver(node, &info) < 0)
diff --git a/arch/powerpc/platforms/pasemi/msi.c b/arch/powerpc/platforms/pasemi/msi.c
index d9af76342d99..d9cd510c8865 100644
--- a/arch/powerpc/platforms/pasemi/msi.c
+++ b/arch/powerpc/platforms/pasemi/msi.c
@@ -68,7 +68,7 @@ static void pasemi_msi_teardown_msi_irqs(struct pci_dev *pdev)
         pr_debug("pasemi_msi_teardown_msi_irqs, pdev %p\n", pdev);
 
         for_each_pci_msi_entry(entry, pdev) {
-                if (entry->irq == NO_IRQ)
+                if (!entry->irq)
                         continue;
 
                 hwirq = virq_to_hw(entry->irq);
@@ -109,7 +109,7 @@ static int pasemi_msi_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
                 }
 
                 virq = irq_create_mapping(msi_mpic->irqhost, hwirq);
-                if (virq == NO_IRQ) {
+                if (!virq) {
                         pr_debug("pasemi_msi: failed mapping hwirq 0x%x\n",
                                   hwirq);
                         msi_bitmap_free_hwirqs(&msi_mpic->msi_bitmap, hwirq,
diff --git a/arch/powerpc/platforms/pasemi/setup.c b/arch/powerpc/platforms/pasemi/setup.c
index 1d0c3a621a38..3182400cf48f 100644
--- a/arch/powerpc/platforms/pasemi/setup.c
+++ b/arch/powerpc/platforms/pasemi/setup.c
@@ -59,7 +59,7 @@ struct mce_regs {
 
 static struct mce_regs mce_regs[MAX_MCE_REGS];
 static int num_mce_regs;
-static int nmi_virq = NO_IRQ;
+static int nmi_virq = 0;
 
 
 static void __noreturn pas_restart(char *cmd)
@@ -264,7 +264,7 @@ static int pas_machine_check_handler(struct pt_regs *regs)
         srr0 = regs->nip;
         srr1 = regs->msr;
 
-        if (nmi_virq != NO_IRQ && mpic_get_mcirq() == nmi_virq) {
+        if (nmi_virq && mpic_get_mcirq() == nmi_virq) {
                 printk(KERN_ERR "NMI delivered\n");
                 debugger(regs);
                 mpic_end_irq(irq_get_irq_data(nmi_virq));
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);
                 }
diff --git a/arch/powerpc/platforms/powernv/opal-irqchip.c b/arch/powerpc/platforms/powernv/opal-irqchip.c
index ed8bba68a162..998316bf2dad 100644
--- a/arch/powerpc/platforms/powernv/opal-irqchip.c
+++ b/arch/powerpc/platforms/powernv/opal-irqchip.c
@@ -222,7 +222,7 @@ int __init opal_event_init(void)
                 /* Get hardware and virtual IRQ */
                 irq = be32_to_cpup(irqs);
                 virq = irq_create_mapping(NULL, irq);
-                if (virq == NO_IRQ) {
+                if (!virq) {
                         pr_warn("Failed to map irq 0x%x\n", irq);
                         continue;
                 }
@@ -260,7 +260,7 @@ machine_arch_initcall(powernv, opal_event_init);
 int opal_event_request(unsigned int opal_event_nr)
 {
         if (WARN_ON_ONCE(!opal_event_irqchip.domain))
-                return NO_IRQ;
+                return 0;
 
         return irq_create_mapping(opal_event_irqchip.domain, opal_event_nr);
 }
diff --git a/arch/powerpc/platforms/powernv/pci-cxl.c b/arch/powerpc/platforms/powernv/pci-cxl.c
index 1349a099c74c..94498a04558b 100644
--- a/arch/powerpc/platforms/powernv/pci-cxl.c
+++ b/arch/powerpc/platforms/powernv/pci-cxl.c
@@ -344,7 +344,7 @@ int pnv_cxl_cx4_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
                         return (hwirq ? hwirq : -ENOMEM);
 
                 virq = irq_create_mapping(NULL, hwirq);
-                if (virq == NO_IRQ) {
+                if (!virq) {
                         pr_warn("%s: Failed to map cxl mode MSI to linux irq\n",
                                 pci_name(pdev));
                         return -ENOMEM;
@@ -374,7 +374,7 @@ void pnv_cxl_cx4_teardown_msi_irqs(struct pci_dev *pdev)
                 return;
 
         for_each_pci_msi_entry(entry, pdev) {
-                if (entry->irq == NO_IRQ)
+                if (!entry->irq)
                         continue;
                 hwirq = virq_to_hw(entry->irq);
                 irq_set_msi_desc(entry->irq, NULL);
diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
index a21d831c1114..d6a4a61ede3d 100644
--- a/arch/powerpc/platforms/powernv/pci.c
+++ b/arch/powerpc/platforms/powernv/pci.c
@@ -186,7 +186,7 @@ int pnv_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
                         return -ENOSPC;
                 }
                 virq = irq_create_mapping(NULL, phb->msi_base + hwirq);
-                if (virq == NO_IRQ) {
+                if (!virq) {
                         pr_warn("%s: Failed to map MSI to linux irq\n",
                                 pci_name(pdev));
                         msi_bitmap_free_hwirqs(&phb->msi_bmp, hwirq, 1);
@@ -217,7 +217,7 @@ void pnv_teardown_msi_irqs(struct pci_dev *pdev)
                 return;
 
         for_each_pci_msi_entry(entry, pdev) {
-                if (entry->irq == NO_IRQ)
+                if (!entry->irq)
                         continue;
                 hwirq = virq_to_hw(entry->irq);
                 irq_set_msi_desc(entry->irq, NULL);
diff --git a/arch/powerpc/platforms/ps3/interrupt.c b/arch/powerpc/platforms/ps3/interrupt.c
index b831638e6f4a..98f8c3611133 100644
--- a/arch/powerpc/platforms/ps3/interrupt.c
+++ b/arch/powerpc/platforms/ps3/interrupt.c
@@ -192,7 +192,7 @@ static int ps3_virq_setup(enum ps3_cpu_binding cpu, unsigned long outlet,
 
         *virq = irq_create_mapping(NULL, outlet);
 
-        if (*virq == NO_IRQ) {
+        if (!*virq) {
                 FAIL("%s:%d: irq_create_mapping failed: outlet %lu\n",
                         __func__, __LINE__, outlet);
                 result = -ENOMEM;
@@ -339,7 +339,7 @@ int ps3_event_receive_port_setup(enum ps3_cpu_binding cpu, unsigned int *virq)
         if (result) {
                 FAIL("%s:%d: lv1_construct_event_receive_port failed: %s\n",
                         __func__, __LINE__, ps3_result(result));
-                *virq = NO_IRQ;
+                *virq = 0;
                 return result;
         }
 
@@ -418,7 +418,7 @@ int ps3_sb_event_receive_port_setup(struct ps3_system_bus_device *dev,
                         " failed: %s\n", __func__, __LINE__,
                         ps3_result(result));
                 ps3_event_receive_port_destroy(*virq);
-                *virq = NO_IRQ;
+                *virq = 0;
                 return result;
         }
 
@@ -724,12 +724,12 @@ static unsigned int ps3_get_irq(void)
         asm volatile("cntlzd %0,%1" : "=r" (plug) : "r" (x));
         plug &= 0x3f;
 
-        if (unlikely(plug == NO_IRQ)) {
+        if (unlikely(!plug)) {
                 DBG("%s:%d: no plug found: thread_id %llu\n", __func__,
                         __LINE__, pd->thread_id);
                 dump_bmp(&per_cpu(ps3_private, 0));
                 dump_bmp(&per_cpu(ps3_private, 1));
-                return NO_IRQ;
+                return 0;
         }
 
 #if defined(DEBUG)
diff --git a/arch/powerpc/platforms/ps3/smp.c b/arch/powerpc/platforms/ps3/smp.c
index 3c7707af3384..60154d08debf 100644
--- a/arch/powerpc/platforms/ps3/smp.c
+++ b/arch/powerpc/platforms/ps3/smp.c
@@ -91,7 +91,7 @@ static void __init ps3_smp_probe(void)
                         result = smp_request_message_ipi(virqs[i], i);
 
                         if (result)
-                                virqs[i] = NO_IRQ;
+                                virqs[i] = 0;
                         else
                                 ps3_register_ipi_irq(cpu, virqs[i]);
                 }
@@ -112,7 +112,7 @@ void ps3_smp_cleanup_cpu(int cpu)
         for (i = 0; i < MSG_COUNT; i++) {
                 /* Can't call free_irq from interrupt context. */
                 ps3_event_receive_port_destroy(virqs[i]);
-                virqs[i] = NO_IRQ;
+                virqs[i] = 0;
         }
 
         DBG(" <- %s:%d: (%d)\n", __func__, __LINE__, cpu);
diff --git a/arch/powerpc/platforms/ps3/spu.c b/arch/powerpc/platforms/ps3/spu.c
index 492b2575e0d2..b54850845466 100644
--- a/arch/powerpc/platforms/ps3/spu.c
+++ b/arch/powerpc/platforms/ps3/spu.c
@@ -284,7 +284,7 @@ fail_alloc_2:
 fail_alloc_1:
         ps3_spe_irq_destroy(spu->irqs[0]);
 fail_alloc_0:
-        spu->irqs[0] = spu->irqs[1] = spu->irqs[2] = NO_IRQ;
+        spu->irqs[0] = spu->irqs[1] = spu->irqs[2] = 0;
         return result;
 }
 
@@ -334,7 +334,7 @@ static int ps3_destroy_spu(struct spu *spu)
         ps3_spe_irq_destroy(spu->irqs[1]);
         ps3_spe_irq_destroy(spu->irqs[0]);
 
-        spu->irqs[0] = spu->irqs[1] = spu->irqs[2] = NO_IRQ;
+        spu->irqs[0] = spu->irqs[1] = spu->irqs[2] = 0;
 
         spu_unmap(spu);
 
diff --git a/arch/powerpc/platforms/pseries/event_sources.c b/arch/powerpc/platforms/pseries/event_sources.c
index a6ddca833119..32187dc76730 100644
--- a/arch/powerpc/platforms/pseries/event_sources.c
+++ b/arch/powerpc/platforms/pseries/event_sources.c
@@ -34,7 +34,7 @@ void request_event_sources_irqs(struct device_node *np,
                 if (count > 15)
                         break;
                 virqs[count] = irq_create_of_mapping(&oirq);
-                if (virqs[count] == NO_IRQ) {
+                if (!virqs[count]) {
                         pr_err("event-sources: Unable to allocate "
                                "interrupt number for %s\n",
                                np->full_name);
diff --git a/arch/powerpc/platforms/pseries/msi.c b/arch/powerpc/platforms/pseries/msi.c
index 543a6386f3eb..326ef0dd6038 100644
--- a/arch/powerpc/platforms/pseries/msi.c
+++ b/arch/powerpc/platforms/pseries/msi.c
@@ -119,7 +119,7 @@ static void rtas_teardown_msi_irqs(struct pci_dev *pdev)
         struct msi_desc *entry;
 
         for_each_pci_msi_entry(entry, pdev) {
-                if (entry->irq == NO_IRQ)
+                if (!entry->irq)
                         continue;
 
                 irq_set_msi_desc(entry->irq, NULL);
@@ -471,7 +471,7 @@ again:
 
                 virq = irq_create_mapping(NULL, hwirq);
 
-                if (virq == NO_IRQ) {
+                if (!virq) {
                         pr_debug("rtas_msi: Failed mapping hwirq %d\n", hwirq);
                         return -ENOSPC;
                 }
@@ -490,7 +490,7 @@ again:
 static void rtas_msi_pci_irq_fixup(struct pci_dev *pdev)
 {
         /* No LSI -> leave MSIs (if any) configured */
-        if (pdev->irq == NO_IRQ) {
+        if (!pdev->irq) {
                 dev_dbg(&pdev->dev, "rtas_msi: no LSI, nothing to do.\n");
                 return;
         }
diff --git a/arch/powerpc/platforms/pseries/setup.c b/arch/powerpc/platforms/pseries/setup.c
index 4ffcaa6f8670..776900043e2a 100644
--- a/arch/powerpc/platforms/pseries/setup.c
+++ b/arch/powerpc/platforms/pseries/setup.c
@@ -114,7 +114,7 @@ static void pseries_8259_cascade(struct irq_desc *desc)
         struct irq_chip *chip = irq_desc_get_chip(desc);
         unsigned int cascade_irq = i8259_irq();
 
-        if (cascade_irq != NO_IRQ)
+        if (cascade_irq)
                 generic_handle_irq(cascade_irq);
 
         chip->irq_eoi(&desc->irq_data);
@@ -141,7 +141,7 @@ static void __init pseries_setup_i8259_cascade(void)
         }
 
         cascade = irq_of_parse_and_map(found, 0);
-        if (cascade == NO_IRQ) {
+        if (!cascade) {
                 printk(KERN_ERR "pic: failed to map cascade interrupt");
                 return;
         }
diff --git a/arch/powerpc/sysdev/axonram.c b/arch/powerpc/sysdev/axonram.c
index 9144204442eb..ada29eaed6e2 100644
--- a/arch/powerpc/sysdev/axonram.c
+++ b/arch/powerpc/sysdev/axonram.c
@@ -240,7 +240,7 @@ static int axon_ram_probe(struct platform_device *device)
         device_add_disk(&device->dev, bank->disk);
 
         bank->irq_id = irq_of_parse_and_map(device->dev.of_node, 0);
-        if (bank->irq_id == NO_IRQ) {
+        if (!bank->irq_id) {
                 dev_err(&device->dev, "Cannot access ECC interrupt ID\n");
                 rc = -EFAULT;
                 goto failed;
@@ -250,7 +250,7 @@ static int axon_ram_probe(struct platform_device *device)
                         AXON_RAM_IRQ_FLAGS, bank->disk->disk_name, device);
         if (rc != 0) {
                 dev_err(&device->dev, "Cannot register ECC interrupt handler\n");
-                bank->irq_id = NO_IRQ;
+                bank->irq_id = 0;
                 rc = -EFAULT;
                 goto failed;
         }
@@ -268,7 +268,7 @@ static int axon_ram_probe(struct platform_device *device)
 
 failed:
         if (bank != NULL) {
-                if (bank->irq_id != NO_IRQ)
+                if (bank->irq_id)
                         free_irq(bank->irq_id, device);
                 if (bank->disk != NULL) {
                         if (bank->disk->major > 0)
diff --git a/arch/powerpc/sysdev/cpm1.c b/arch/powerpc/sysdev/cpm1.c
index 81d49476c47e..3c0eb9b25535 100644
--- a/arch/powerpc/sysdev/cpm1.c
+++ b/arch/powerpc/sysdev/cpm1.c
@@ -132,7 +132,7 @@ unsigned int cpm_pic_init(void)
 {
         struct device_node *np = NULL;
         struct resource res;
-        unsigned int sirq = NO_IRQ, hwirq, eirq;
+        unsigned int sirq = 0, hwirq, eirq;
         int ret;
 
         pr_debug("cpm_pic_init\n");
@@ -154,7 +154,7 @@ unsigned int cpm_pic_init(void)
                 goto end;
 
         sirq = irq_of_parse_and_map(np, 0);
-        if (sirq == NO_IRQ)
+        if (!sirq)
                 goto end;
 
         /* Initialize the CPM interrupt controller. */
@@ -168,7 +168,7 @@ unsigned int cpm_pic_init(void)
         cpm_pic_host = irq_domain_add_linear(np, 64, &cpm_pic_host_ops, NULL);
         if (cpm_pic_host == NULL) {
                 printk(KERN_ERR "CPM2 PIC: failed to allocate irq host!\n");
-                sirq = NO_IRQ;
+                sirq = 0;
                 goto end;
         }
 
@@ -182,7 +182,7 @@ unsigned int cpm_pic_init(void)
         }
 
         eirq = irq_of_parse_and_map(np, 0);
-        if (eirq == NO_IRQ)
+        if (!eirq)
                 goto end;
 
         if (setup_irq(eirq, &cpm_error_irqaction))
diff --git a/arch/powerpc/sysdev/ehv_pic.c b/arch/powerpc/sysdev/ehv_pic.c
index bffcc7a486a1..48866e6c1efb 100644
--- a/arch/powerpc/sysdev/ehv_pic.c
+++ b/arch/powerpc/sysdev/ehv_pic.c
@@ -155,7 +155,7 @@ static struct irq_chip ehv_pic_direct_eoi_irq_chip = {
         .irq_set_type   = ehv_pic_set_irq_type,
 };
 
-/* Return an interrupt vector or NO_IRQ if no interrupt is pending. */
+/* Return an interrupt vector or 0 if no interrupt is pending. */
 unsigned int ehv_pic_get_irq(void)
 {
         int irq;
@@ -168,7 +168,7 @@ unsigned int ehv_pic_get_irq(void)
                 ev_int_iack(0, &irq); /* legacy mode */
 
         if (irq == 0xFFFF)    /* 0xFFFF --> no irq is pending */
-                return NO_IRQ;
+                return 0;
 
         /*
          * this will also setup revmap[] in the slow path for the first
diff --git a/arch/powerpc/sysdev/fsl_gtm.c b/arch/powerpc/sysdev/fsl_gtm.c
index 06ac3c61b3d0..a6f0b96ce2c9 100644
--- a/arch/powerpc/sysdev/fsl_gtm.c
+++ b/arch/powerpc/sysdev/fsl_gtm.c
@@ -406,7 +406,7 @@ static int __init fsl_gtm_init(void)
                         unsigned int irq;
 
                         irq = irq_of_parse_and_map(np, i);
-                        if (irq == NO_IRQ) {
+                        if (!irq) {
                                 pr_err("%s: not enough interrupts specified\n",
                                        np->full_name);
                                 goto err;
diff --git a/arch/powerpc/sysdev/fsl_mpic_err.c b/arch/powerpc/sysdev/fsl_mpic_err.c
index b83f32562a37..488ec453038a 100644
--- a/arch/powerpc/sysdev/fsl_mpic_err.c
+++ b/arch/powerpc/sysdev/fsl_mpic_err.c
@@ -115,8 +115,8 @@ static irqreturn_t fsl_error_int_handler(int irq, void *data)
                 errint = __builtin_clz(eisr);
                 cascade_irq = irq_linear_revmap(mpic->irqhost,
                                  mpic->err_int_vecs[errint]);
-                WARN_ON(cascade_irq == NO_IRQ);
-                if (cascade_irq != NO_IRQ) {
+                WARN_ON(!cascade_irq);
+                if (cascade_irq) {
                         generic_handle_irq(cascade_irq);
                 } else {
                         eimr |=  1 << (31 - errint);
@@ -134,7 +134,7 @@ void mpic_err_int_init(struct mpic *mpic, irq_hw_number_t irqnum)
         int ret;
 
         virq = irq_create_mapping(mpic->irqhost, irqnum);
-        if (virq == NO_IRQ) {
+        if (!virq) {
                 pr_err("Error interrupt setup failed\n");
                 return;
         }
diff --git a/arch/powerpc/sysdev/fsl_msi.c b/arch/powerpc/sysdev/fsl_msi.c
index 3a2be3676f43..8a244828782e 100644
--- a/arch/powerpc/sysdev/fsl_msi.c
+++ b/arch/powerpc/sysdev/fsl_msi.c
@@ -131,7 +131,7 @@ static void fsl_teardown_msi_irqs(struct pci_dev *pdev)
         irq_hw_number_t hwirq;
 
         for_each_pci_msi_entry(entry, pdev) {
-                if (entry->irq == NO_IRQ)
+                if (!entry->irq)
                         continue;
                 hwirq = virq_to_hw(entry->irq);
                 msi_data = irq_get_chip_data(entry->irq);
@@ -250,7 +250,7 @@ static int fsl_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
 
                 virq = irq_create_mapping(msi_data->irqhost, hwirq);
 
-                if (virq == NO_IRQ) {
+                if (!virq) {
                         dev_err(&pdev->dev, "fail mapping hwirq %i\n", hwirq);
                         msi_bitmap_free_hwirqs(&msi_data->bitmap, hwirq, 1);
                         rc = -ENOSPC;
@@ -285,7 +285,7 @@ static irqreturn_t fsl_msi_cascade(int irq, void *data)
         msir_index = cascade_data->index;
 
         if (msir_index >= NR_MSI_REG_MAX)
-                cascade_irq = NO_IRQ;
+                cascade_irq = 0;
 
         switch (msi_data->feature & FSL_PIC_IP_MASK) {
         case FSL_PIC_IP_MPIC:
@@ -315,7 +315,7 @@ static irqreturn_t fsl_msi_cascade(int irq, void *data)
                 cascade_irq = irq_linear_revmap(msi_data->irqhost,
                                 msi_hwirq(msi_data, msir_index,
                                           intr_index + have_shift));
-                if (cascade_irq != NO_IRQ) {
+                if (cascade_irq) {
                         generic_handle_irq(cascade_irq);
                         ret = IRQ_HANDLED;
                 }
@@ -337,7 +337,7 @@ static int fsl_of_msi_remove(struct platform_device *ofdev)
                 if (msi->cascade_array[i]) {
                         virq = msi->cascade_array[i]->virq;
 
-                        BUG_ON(virq == NO_IRQ);
+                        BUG_ON(!virq);
 
                         free_irq(virq, msi->cascade_array[i]);
                         kfree(msi->cascade_array[i]);
@@ -362,7 +362,7 @@ static int fsl_msi_setup_hwirq(struct fsl_msi *msi, struct platform_device *dev,
         int virt_msir, i, ret;
 
         virt_msir = irq_of_parse_and_map(dev->dev.of_node, irq_index);
-        if (virt_msir == NO_IRQ) {
+        if (!virt_msir) {
                 dev_err(&dev->dev, "%s: Cannot translate IRQ index %d\n",
                         __func__, irq_index);
                 return 0;
diff --git a/arch/powerpc/sysdev/ge/ge_pic.c b/arch/powerpc/sysdev/ge/ge_pic.c
index d57b77573068..02553a8ce191 100644
--- a/arch/powerpc/sysdev/ge/ge_pic.c
+++ b/arch/powerpc/sysdev/ge/ge_pic.c
@@ -102,7 +102,7 @@ static void gef_pic_cascade(struct irq_desc *desc)
          */
         cascade_irq = gef_pic_get_irq();
 
-        if (cascade_irq != NO_IRQ)
+        if (cascade_irq)
                 generic_handle_irq(cascade_irq);
 
         chip->irq_eoi(&desc->irq_data);
@@ -206,7 +206,7 @@ void __init gef_pic_init(struct device_node *np)
 
         /* Map controller */
         gef_pic_cascade_irq = irq_of_parse_and_map(np, 0);
-        if (gef_pic_cascade_irq == NO_IRQ) {
+        if (!gef_pic_cascade_irq) {
                 printk(KERN_ERR "SBC610: failed to map cascade interrupt");
                 return;
         }
@@ -223,12 +223,12 @@ void __init gef_pic_init(struct device_node *np)
 
 /*
  * This is called when we receive an interrupt with apparently comes from this
- * chip - check, returning the highest interrupt generated or return NO_IRQ
+ * chip - check, returning the highest interrupt generated or return 0.
  */
 unsigned int gef_pic_get_irq(void)
 {
         u32 cause, mask, active;
-        unsigned int virq = NO_IRQ;
+        unsigned int virq = 0;
         int hwirq;
 
         cause = in_be32(gef_pic_irq_reg_base + GEF_PIC_INTR_STATUS);
diff --git a/arch/powerpc/sysdev/i8259.c b/arch/powerpc/sysdev/i8259.c
index aa2c186d3115..bafb014e1a7e 100644
--- a/arch/powerpc/sysdev/i8259.c
+++ b/arch/powerpc/sysdev/i8259.c
@@ -68,9 +68,9 @@ unsigned int i8259_irq(void)
                 if (!pci_intack)
                         outb(0x0B, 0x20);       /* ISR register */
                 if(~inb(0x20) & 0x80)
-                        irq = NO_IRQ;
+                        irq = 0;
         } else if (irq == 0xff)
-                irq = NO_IRQ;
+                irq = 0;
 
         if (lock)
                 raw_spin_unlock(&i8259_lock);
diff --git a/arch/powerpc/sysdev/ipic.c b/arch/powerpc/sysdev/ipic.c
index f76ee39cb337..f267ee0afc08 100644
--- a/arch/powerpc/sysdev/ipic.c
+++ b/arch/powerpc/sysdev/ipic.c
@@ -853,7 +853,7 @@ void ipic_clear_mcp_status(u32 mask)
         ipic_write(primary_ipic->regs, IPIC_SERMR, mask);
 }
 
-/* Return an interrupt vector or NO_IRQ if no interrupt is pending. */
+/* Return an interrupt vector or 0 if no interrupt is pending. */
 unsigned int ipic_get_irq(void)
 {
         int irq;
@@ -864,7 +864,7 @@ unsigned int ipic_get_irq(void)
         irq = ipic_read(primary_ipic->regs, IPIC_SIVCR) & IPIC_SIVCR_VECTOR_MASK;
 
         if (irq == 0)    /* 0 --> no irq is pending */
-                return NO_IRQ;
+                return 0;
 
         return irq_linear_revmap(primary_ipic->irqhost, irq);
 }
diff --git a/arch/powerpc/sysdev/mpc8xx_pic.c b/arch/powerpc/sysdev/mpc8xx_pic.c
index b7cf7abff2eb..3e828b20c21e 100644
--- a/arch/powerpc/sysdev/mpc8xx_pic.c
+++ b/arch/powerpc/sysdev/mpc8xx_pic.c
@@ -79,7 +79,7 @@ unsigned int mpc8xx_get_irq(void)
         irq = in_be32(&siu_reg->sc_sivec) >> 26;
 
         if (irq == PIC_VEC_SPURRIOUS)
-                irq = NO_IRQ;
+                irq = 0;
 
         return irq_linear_revmap(mpc8xx_pic_host, irq);
 
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;
                 }
diff --git a/arch/powerpc/sysdev/mpic_msgr.c b/arch/powerpc/sysdev/mpic_msgr.c
index 3f165d972a0e..db2286be5d9a 100644
--- a/arch/powerpc/sysdev/mpic_msgr.c
+++ b/arch/powerpc/sysdev/mpic_msgr.c
@@ -238,7 +238,7 @@ static int mpic_msgr_probe(struct platform_device *dev)
 
                 if (receive_mask & (1 << i)) {
                         msgr->irq = irq_of_parse_and_map(np, irq_index);
-                        if (msgr->irq == NO_IRQ) {
+                        if (!msgr->irq) {
                                 dev_err(&dev->dev,
                                                 "Missing interrupt specifier");
                                 kfree(msgr);
@@ -246,7 +246,7 @@ static int mpic_msgr_probe(struct platform_device *dev)
                         }
                         irq_index += 1;
                 } else {
-                        msgr->irq = NO_IRQ;
+                        msgr->irq = 0;
                 }
 
                 mpic_msgrs[reg_number] = msgr;
diff --git a/arch/powerpc/sysdev/mpic_u3msi.c b/arch/powerpc/sysdev/mpic_u3msi.c
index 2cbc7e29b85f..cfc1c57d760f 100644
--- a/arch/powerpc/sysdev/mpic_u3msi.c
+++ b/arch/powerpc/sysdev/mpic_u3msi.c
@@ -110,7 +110,7 @@ static void u3msi_teardown_msi_irqs(struct pci_dev *pdev)
         irq_hw_number_t hwirq;
 
         for_each_pci_msi_entry(entry, pdev) {
-                if (entry->irq == NO_IRQ)
+                if (!entry->irq)
                         continue;
 
                 hwirq = virq_to_hw(entry->irq);
@@ -155,7 +155,7 @@ static int u3msi_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
                 msg.address_hi = addr >> 32;
 
                 virq = irq_create_mapping(msi_mpic->irqhost, hwirq);
-                if (virq == NO_IRQ) {
+                if (!virq) {
                         pr_debug("u3msi: failed mapping hwirq 0x%x\n", hwirq);
                         msi_bitmap_free_hwirqs(&msi_mpic->msi_bitmap, hwirq, 1);
                         return -ENOSPC;
diff --git a/arch/powerpc/sysdev/mv64x60_pic.c b/arch/powerpc/sysdev/mv64x60_pic.c
index 0f842dd16bcd..a79953deb489 100644
--- a/arch/powerpc/sysdev/mv64x60_pic.c
+++ b/arch/powerpc/sysdev/mv64x60_pic.c
@@ -272,7 +272,7 @@ unsigned int mv64x60_get_irq(void)
         u32 cause;
         int level1;
         irq_hw_number_t hwirq;
-        int virq = NO_IRQ;
+        int virq = 0;
 
         cause = in_le32(mv64x60_irq_reg_base + MV64X60_IC_CPU0_SELECT_CAUSE);
         if (cause & MV64X60_SELECT_CAUSE_HIGH) {
diff --git a/arch/powerpc/sysdev/pmi.c b/arch/powerpc/sysdev/pmi.c
index 8a0b77a3ec0c..9ea6a221d9d5 100644
--- a/arch/powerpc/sysdev/pmi.c
+++ b/arch/powerpc/sysdev/pmi.c
@@ -158,7 +158,7 @@ static int pmi_of_probe(struct platform_device *dev)
         data->dev = dev;
 
         data->irq = irq_of_parse_and_map(np, 0);
-        if (data->irq == NO_IRQ) {
+        if (!data->irq) {
                 printk(KERN_ERR "pmi: invalid interrupt.\n");
                 rc = -EFAULT;
                 goto error_cleanup_iomap;
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;
diff --git a/arch/powerpc/sysdev/ppc4xx_msi.c b/arch/powerpc/sysdev/ppc4xx_msi.c
index 8fb806135043..590dab4f47d6 100644
--- a/arch/powerpc/sysdev/ppc4xx_msi.c
+++ b/arch/powerpc/sysdev/ppc4xx_msi.c
@@ -102,7 +102,7 @@ static int ppc4xx_setup_msi_irqs(struct pci_dev *dev, int nvec, int type)
                                         __func__);
                 }
                 virq = irq_of_parse_and_map(msi_data->msi_dev, int_no);
-                if (virq == NO_IRQ) {
+                if (!virq) {
                         dev_err(&dev->dev, "%s: fail mapping irq\n", __func__);
                         msi_bitmap_free_hwirqs(&msi_data->bitmap, int_no, 1);
                         return -ENOSPC;
@@ -129,7 +129,7 @@ void ppc4xx_teardown_msi_irqs(struct pci_dev *dev)
         dev_dbg(&dev->dev, "PCIE-MSI: tearing down msi irqs\n");
 
         for_each_pci_msi_entry(entry, dev) {
-                if (entry->irq == NO_IRQ)
+                if (!entry->irq)
                         continue;
                 hwirq = virq_to_hw(entry->irq);
                 irq_set_msi_desc(entry->irq, NULL);
@@ -201,7 +201,7 @@ static int ppc4xx_of_msi_remove(struct platform_device *dev)
 
         for (i = 0; i < msi_irqs; i++) {
                 virq = msi->msi_virqs[i];
-                if (virq != NO_IRQ)
+                if (virq)
                         irq_dispose_mapping(virq);
         }
 
diff --git a/arch/powerpc/sysdev/ppc4xx_soc.c b/arch/powerpc/sysdev/ppc4xx_soc.c
index 5c77c9ba33aa..d41134d2f786 100644
--- a/arch/powerpc/sysdev/ppc4xx_soc.c
+++ b/arch/powerpc/sysdev/ppc4xx_soc.c
@@ -109,7 +109,7 @@ static int __init ppc4xx_l2c_probe(void)
 
         /* Get and map irq number from device tree */
         irq = irq_of_parse_and_map(np, 0);
-        if (irq == NO_IRQ) {
+        if (!irq) {
                 printk(KERN_ERR "irq_of_parse_and_map failed\n");
                 of_node_put(np);
                 return -ENODEV;
diff --git a/arch/powerpc/sysdev/tsi108_pci.c b/arch/powerpc/sysdev/tsi108_pci.c
index 379de955aae3..57c971b7839c 100644
--- a/arch/powerpc/sysdev/tsi108_pci.c
+++ b/arch/powerpc/sysdev/tsi108_pci.c
@@ -433,7 +433,7 @@ void tsi108_irq_cascade(struct irq_desc *desc)
         struct irq_chip *chip = irq_desc_get_chip(desc);
         unsigned int cascade_irq = get_pci_source();
 
-        if (cascade_irq != NO_IRQ)
+        if (cascade_irq)
                 generic_handle_irq(cascade_irq);
 
         chip->irq_eoi(&desc->irq_data);
diff --git a/arch/powerpc/sysdev/uic.c b/arch/powerpc/sysdev/uic.c
index 6893d8f236df..a00949f3e378 100644
--- a/arch/powerpc/sysdev/uic.c
+++ b/arch/powerpc/sysdev/uic.c
@@ -319,7 +319,7 @@ void __init uic_init_tree(void)
         }
 }
 
-/* Return an interrupt vector or NO_IRQ if no interrupt is pending. */
+/* Return an interrupt vector or 0 if no interrupt is pending. */
 unsigned int uic_get_irq(void)
 {
         u32 msr;
diff --git a/arch/powerpc/sysdev/xics/icp-hv.c b/arch/powerpc/sysdev/xics/icp-hv.c
index c1917cf67c3d..e7fa26c4ff73 100644
--- a/arch/powerpc/sysdev/xics/icp-hv.c
+++ b/arch/powerpc/sysdev/xics/icp-hv.c
@@ -112,10 +112,10 @@ static unsigned int icp_hv_get_irq(void)
         unsigned int irq;
 
         if (vec == XICS_IRQ_SPURIOUS)
-                return NO_IRQ;
+                return 0;
 
         irq = irq_find_mapping(xics_host, vec);
-        if (likely(irq != NO_IRQ)) {
+        if (likely(irq)) {
                 xics_push_cppr(vec);
                 return irq;
         }
@@ -126,7 +126,7 @@ static unsigned int icp_hv_get_irq(void)
         /* We might learn about it later, so EOI it */
         icp_hv_set_xirr(xirr);
 
-        return NO_IRQ;
+        return 0;
 }
 
 static void icp_hv_set_cpu_priority(unsigned char cppr)
diff --git a/arch/powerpc/sysdev/xics/icp-native.c b/arch/powerpc/sysdev/xics/icp-native.c
index afdf62f2a695..8a6a043e239b 100644
--- a/arch/powerpc/sysdev/xics/icp-native.c
+++ b/arch/powerpc/sysdev/xics/icp-native.c
@@ -124,10 +124,10 @@ static unsigned int icp_native_get_irq(void)
         unsigned int irq;
 
         if (vec == XICS_IRQ_SPURIOUS)
-                return NO_IRQ;
+                return 0;
 
         irq = irq_find_mapping(xics_host, vec);
-        if (likely(irq != NO_IRQ)) {
+        if (likely(irq)) {
                 xics_push_cppr(vec);
                 return irq;
         }
@@ -138,7 +138,7 @@ static unsigned int icp_native_get_irq(void)
         /* We might learn about it later, so EOI it */
         icp_native_set_xirr(xirr);
 
-        return NO_IRQ;
+        return 0;
 }
 
 #ifdef CONFIG_SMP
diff --git a/arch/powerpc/sysdev/xics/icp-opal.c b/arch/powerpc/sysdev/xics/icp-opal.c
index 57d72f10a97f..7357cfddb040 100644
--- a/arch/powerpc/sysdev/xics/icp-opal.c
+++ b/arch/powerpc/sysdev/xics/icp-opal.c
@@ -51,14 +51,14 @@ static unsigned int icp_opal_get_irq(void)
 
         rc = opal_int_get_xirr(&xirr, false);
         if (rc < 0)
-                return NO_IRQ;
+                return 0;
         xirr = be32_to_cpu(xirr);
         vec = xirr & 0x00ffffff;
         if (vec == XICS_IRQ_SPURIOUS)
-                return NO_IRQ;
+                return 0;
 
         irq = irq_find_mapping(xics_host, vec);
-        if (likely(irq != NO_IRQ)) {
+        if (likely(irq)) {
                 xics_push_cppr(vec);
                 return irq;
         }
@@ -69,7 +69,7 @@ static unsigned int icp_opal_get_irq(void)
         /* We might learn about it later, so EOI it */
         opal_int_eoi(xirr);
 
-        return NO_IRQ;
+        return 0;
 }
 
 static void icp_opal_set_cpu_priority(unsigned char cppr)
diff --git a/arch/powerpc/sysdev/xics/xics-common.c b/arch/powerpc/sysdev/xics/xics-common.c
index 9d530f479588..69d858e51ac7 100644
--- a/arch/powerpc/sysdev/xics/xics-common.c
+++ b/arch/powerpc/sysdev/xics/xics-common.c
@@ -131,7 +131,7 @@ static void xics_request_ipi(void)
         unsigned int ipi;
 
         ipi = irq_create_mapping(xics_host, XICS_IPI);
-        BUG_ON(ipi == NO_IRQ);
+        BUG_ON(!ipi);
 
         /*
          * IPIs are marked IRQF_PERCPU. The handler was set in map.
diff --git a/drivers/macintosh/macio_asic.c b/drivers/macintosh/macio_asic.c
index b6819f0fc608..3f041b187033 100644
--- a/drivers/macintosh/macio_asic.c
+++ b/drivers/macintosh/macio_asic.c
@@ -236,7 +236,7 @@ static void macio_create_fixup_irq(struct macio_dev *dev, int index,
         unsigned int irq;
 
         irq = irq_create_mapping(NULL, line);
-        if (irq != NO_IRQ) {
+        if (!irq) {
                 dev->interrupt[index].start = irq;
                 dev->interrupt[index].flags = IORESOURCE_IRQ;
                 dev->interrupt[index].name = dev_name(&dev->ofdev.dev);
@@ -299,7 +299,7 @@ static void macio_setup_interrupts(struct macio_dev *dev)
                         break;
                 res = &dev->interrupt[j];
                 irq = irq_of_parse_and_map(np, i++);
-                if (irq == NO_IRQ)
+                if (!irq)
                         break;
                 res->start = irq;
                 res->flags = IORESOURCE_IRQ;
diff --git a/drivers/macintosh/rack-meter.c b/drivers/macintosh/rack-meter.c
index 465c52219639..775527135b93 100644
--- a/drivers/macintosh/rack-meter.c
+++ b/drivers/macintosh/rack-meter.c
@@ -427,7 +427,7 @@ static int rackmeter_probe(struct macio_dev* mdev,
         rm->irq = macio_irq(mdev, 1);
 #else
         rm->irq = irq_of_parse_and_map(i2s, 1);
-        if (rm->irq == NO_IRQ ||
+        if (!rm->irq ||
             of_address_to_resource(i2s, 0, &ri2s) ||
             of_address_to_resource(i2s, 1, &rdma)) {
                 printk(KERN_ERR
diff --git a/drivers/macintosh/smu.c b/drivers/macintosh/smu.c
index d6f72c826c1c..08edb2c25b60 100644
--- a/drivers/macintosh/smu.c
+++ b/drivers/macintosh/smu.c
@@ -279,7 +279,7 @@ int smu_queue_cmd(struct smu_cmd *cmd)
         spin_unlock_irqrestore(&smu->lock, flags);
 
         /* Workaround for early calls when irq isn't available */
-        if (!smu_irq_inited || smu->db_irq == NO_IRQ)
+        if (!smu_irq_inited || !smu->db_irq)
                 smu_spinwait_cmd(cmd);
 
         return 0;
@@ -498,8 +498,8 @@ int __init smu_init (void)
         INIT_LIST_HEAD(&smu->cmd_list);
         INIT_LIST_HEAD(&smu->cmd_i2c_list);
         smu->of_node = np;
-        smu->db_irq = NO_IRQ;
-        smu->msg_irq = NO_IRQ;
+        smu->db_irq = 0;
+        smu->msg_irq = 0;
 
         /* smu_cmdbuf_abs is in the low 2G of RAM, can be converted to a
          * 32 bits value safely
@@ -587,13 +587,13 @@ static int smu_late_init(void)
 
         if (smu->db_node) {
                 smu->db_irq = irq_of_parse_and_map(smu->db_node, 0);
-                if (smu->db_irq == NO_IRQ)
+                if (!smu->db_irq)
                         printk(KERN_ERR "smu: failed to map irq for node %s\n",
                                smu->db_node->full_name);
         }
         if (smu->msg_node) {
                 smu->msg_irq = irq_of_parse_and_map(smu->msg_node, 0);
-                if (smu->msg_irq == NO_IRQ)
+                if (!smu->msg_irq)
                         printk(KERN_ERR "smu: failed to map irq for node %s\n",
                                smu->msg_node->full_name);
         }
@@ -602,23 +602,23 @@ static int smu_late_init(void)
          * Try to request the interrupts
          */
 
-        if (smu->db_irq != NO_IRQ) {
+        if (smu->db_irq) {
                 if (request_irq(smu->db_irq, smu_db_intr,
                                 IRQF_SHARED, "SMU doorbell", smu) < 0) {
                         printk(KERN_WARNING "SMU: can't "
                                "request interrupt %d\n",
                                smu->db_irq);
-                        smu->db_irq = NO_IRQ;
+                        smu->db_irq = 0;
                 }
         }
 
-        if (smu->msg_irq != NO_IRQ) {
+        if (smu->msg_irq) {
                 if (request_irq(smu->msg_irq, smu_msg_intr,
                                 IRQF_SHARED, "SMU message", smu) < 0) {
                         printk(KERN_WARNING "SMU: can't "
                                "request interrupt %d\n",
                                smu->msg_irq);
-                        smu->msg_irq = NO_IRQ;
+                        smu->msg_irq = 0;
                 }
         }
 
diff --git a/drivers/macintosh/via-cuda.c b/drivers/macintosh/via-cuda.c
index bad18130f125..2088e23a8002 100644
--- a/drivers/macintosh/via-cuda.c
+++ b/drivers/macintosh/via-cuda.c
@@ -209,7 +209,7 @@ static int __init via_cuda_start(void)
     cuda_irq = IRQ_MAC_ADB;
 #else
     cuda_irq = irq_of_parse_and_map(vias, 0);
-    if (cuda_irq == NO_IRQ) {
+    if (!cuda_irq) {
         printk(KERN_ERR "via-cuda: can't map interrupts for %s\n",
                vias->full_name);
         return -ENODEV;
diff --git a/drivers/macintosh/via-pmu.c b/drivers/macintosh/via-pmu.c
index f8b6d1403c16..91081dcdc272 100644
--- a/drivers/macintosh/via-pmu.c
+++ b/drivers/macintosh/via-pmu.c
@@ -145,7 +145,7 @@ static int pmu_fully_inited;
 static int pmu_has_adb;
 static struct device_node *gpio_node;
 static unsigned char __iomem *gpio_reg;
-static int gpio_irq = NO_IRQ;
+static int gpio_irq = 0;
 static int gpio_irq_enabled = -1;
 static volatile int pmu_suspended;
 static spinlock_t pmu_lock;
@@ -402,7 +402,7 @@ static int __init via_pmu_start(void)
         batt_req.complete = 1;
 
         irq = irq_of_parse_and_map(vias, 0);
-        if (irq == NO_IRQ) {
+        if (!irq) {
                 printk(KERN_ERR "via-pmu: can't map interrupt\n");
                 return -ENODEV;
         }
@@ -424,7 +424,7 @@ static int __init via_pmu_start(void)
                 if (gpio_node)
                         gpio_irq = irq_of_parse_and_map(gpio_node, 0);
 
-                if (gpio_irq != NO_IRQ) {
+                if (gpio_irq) {
                         if (request_irq(gpio_irq, gpio1_interrupt,
                                         IRQF_NO_SUSPEND, "GPIO1 ADB",
                                         (void *)0))
diff --git a/drivers/ps3/ps3-vuart.c b/drivers/ps3/ps3-vuart.c
index 632701a1d993..b7f300b79ffd 100644
--- a/drivers/ps3/ps3-vuart.c
+++ b/drivers/ps3/ps3-vuart.c
@@ -958,7 +958,7 @@ static int ps3_vuart_bus_interrupt_get(void)
 
 fail_request_irq:
         ps3_vuart_irq_destroy(vuart_bus_priv.virq);
-        vuart_bus_priv.virq = NO_IRQ;
+        vuart_bus_priv.virq = 0;
 fail_alloc_irq:
         kfree(vuart_bus_priv.bmp);
         vuart_bus_priv.bmp = NULL;
@@ -982,7 +982,7 @@ static int ps3_vuart_bus_interrupt_put(void)
         free_irq(vuart_bus_priv.virq, &vuart_bus_priv);
 
         ps3_vuart_irq_destroy(vuart_bus_priv.virq);
-        vuart_bus_priv.virq = NO_IRQ;
+        vuart_bus_priv.virq = 0;
 
         kfree(vuart_bus_priv.bmp);
         vuart_bus_priv.bmp = NULL;
diff --git a/sound/aoa/core/gpio-feature.c b/sound/aoa/core/gpio-feature.c
index f34153962d07..71960089e207 100644
--- a/sound/aoa/core/gpio-feature.c
+++ b/sound/aoa/core/gpio-feature.c
@@ -118,7 +118,7 @@ static void get_irq(struct device_node * np, int *irqptr)
         if (np)
                 *irqptr = irq_of_parse_and_map(np, 0);
         else
-                *irqptr = NO_IRQ;
+                *irqptr = 0;
 }
 
 /* 0x4 is outenable, 0x1 is out, thus 4 or 5 */
@@ -336,7 +336,7 @@ static int ftr_set_notify(struct gpio_runtime *rt,
                 return -EINVAL;
         }
 
-        if (irq == NO_IRQ)
+        if (!irq)
                 return -ENODEV;
 
         mutex_lock(&notif->mutex);
diff --git a/sound/ppc/tumbler.c b/sound/ppc/tumbler.c
index c8fafba218a5..58ee8089bbf9 100644
--- a/sound/ppc/tumbler.c
+++ b/sound/ppc/tumbler.c
@@ -1303,19 +1303,19 @@ static int tumbler_init(struct snd_pmac *chip)
                                     &mix->line_mute, 1);
         irq = tumbler_find_device("headphone-detect",
                                   NULL, &mix->hp_detect, 0);
-        if (irq <= NO_IRQ)
+        if (irq <= 0)
                 irq = tumbler_find_device("headphone-detect",
                                           NULL, &mix->hp_detect, 1);
-        if (irq <= NO_IRQ)
+        if (irq <= 0)
                 irq = tumbler_find_device("keywest-gpio15",
                                           NULL, &mix->hp_detect, 1);
         mix->headphone_irq = irq;
         irq = tumbler_find_device("line-output-detect",
                                   NULL, &mix->line_detect, 0);
-        if (irq <= NO_IRQ)
+        if (irq <= 0)
                 irq = tumbler_find_device("line-output-detect",
                                           NULL, &mix->line_detect, 1);
-        if (IS_G4DA && irq <= NO_IRQ)
+        if (IS_G4DA && irq <= 0)
                 irq = tumbler_find_device("keywest-gpio16",
                                           NULL, &mix->line_detect, 1);
         mix->lineout_irq = irq;