[PATCH] genirq: rename desc->handler to desc->chip

This patch-queue improves the generic IRQ layer to be truly generic, by adding
various abstractions and features to it, without impacting existing
functionality.

While the queue can be best described as "fix and improve everything in the
generic IRQ layer that we could think of", and thus it consists of many
smaller features and lots of cleanups, the one feature that stands out most is
the new 'irq chip' abstraction.

The irq-chip abstraction is about describing and coding and IRQ controller
driver by mapping its raw hardware capabilities [and quirks, if needed] in a
straightforward way, without having to think about "IRQ flow"
(level/edge/etc.) type of details.

This stands in contrast with the current 'irq-type' model of genirq
architectures, which 'mixes' raw hardware capabilities with 'flow' details.
The patchset supports both types of irq controller designs at once, and
converts i386 and x86_64 to the new irq-chip design.

As a bonus side-effect of the irq-chip approach, chained interrupt controllers
(master/slave PIC constructs, etc.) are now supported by design as well.

The end result of this patchset intends to be simpler architecture-level code
and more consolidation between architectures.

We reused many bits of code and many concepts from Russell King's ARM IRQ
layer, the merging of which was one of the motivations for this patchset.

This patch:

rename desc->handler to desc->chip.

Originally i did not want to do this, because it's a big patch.  But having
both "desc->handler", "desc->handle_irq" and "action->handler" caused a
large degree of confusion and made the code appear alot less clean than it
truly is.

I have also attempted a dual approach as well by introducing a
desc->chip alias - but that just wasnt robust enough and broke
frequently.

So lets get over with this quickly.  The conversion was done automatically
via scripts and converts all the code in the kernel.

This renaming patch is the first one amongst the patches, so that the
remaining patches can stay flexible and can be merged and split up
without having some big monolithic patch act as a merge barrier.

[akpm@osdl.org: build fix]
[akpm@osdl.org: another build fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

10 files changed, 25 insertions, 25 deletions

diff --git a/arch/powerpc/kernel/crash.c b/arch/powerpc/kernel/crash.c
index e253a45dcf10..1bfad7c2f8c8 100644
--- a/arch/powerpc/kernel/crash.c
+++ b/arch/powerpc/kernel/crash.c
@@ -193,10 +193,10 @@ void default_machine_crash_shutdown(struct pt_regs *regs)
                 struct irq_desc *desc = irq_descp(irq);
 
                 if (desc->status & IRQ_INPROGRESS)
-                        desc->handler->end(irq);
+                        desc->chip->end(irq);
 
                 if (!(desc->status & IRQ_DISABLED))
-                        desc->handler->disable(irq);
+                        desc->chip->disable(irq);
         }
 
         if (ppc_md.kexec_cpu_down)
diff --git a/arch/powerpc/kernel/irq.c b/arch/powerpc/kernel/irq.c
index 40d4c14fde8f..8cfc779d882d 100644
--- a/arch/powerpc/kernel/irq.c
+++ b/arch/powerpc/kernel/irq.c
@@ -120,8 +120,8 @@ int show_interrupts(struct seq_file *p, void *v)
 #else
                 seq_printf(p, "%10u ", kstat_irqs(i));
 #endif /* CONFIG_SMP */
-                if (desc->handler)
-                        seq_printf(p, " %s ", desc->handler->typename);
+                if (desc->chip)
+                        seq_printf(p, " %s ", desc->chip->typename);
                 else
                         seq_puts(p, "  None      ");
                 seq_printf(p, "%s", (desc->status & IRQ_LEVEL) ? "Level " : "Edge  ");
@@ -169,8 +169,8 @@ void fixup_irqs(cpumask_t map)
                         printk("Breaking affinity for irq %i\n", irq);
                         mask = map;
                 }
-                if (irq_desc[irq].handler->set_affinity)
-                        irq_desc[irq].handler->set_affinity(irq, mask);
+                if (irq_desc[irq].chip->set_affinity)
+                        irq_desc[irq].chip->set_affinity(irq, mask);
                 else if (irq_desc[irq].action && !(warned++))
                         printk("Cannot set affinity for irq %i\n", irq);
         }
diff --git a/arch/powerpc/platforms/cell/interrupt.c b/arch/powerpc/platforms/cell/interrupt.c
index 1bbf822b4efc..7bff3cbc5723 100644
--- a/arch/powerpc/platforms/cell/interrupt.c
+++ b/arch/powerpc/platforms/cell/interrupt.c
@@ -307,7 +307,7 @@ static void iic_request_ipi(int ipi, const char *name)
         irq = iic_ipi_to_irq(ipi);
         /* IPIs are marked SA_INTERRUPT as they must run with irqs
          * disabled */
-        get_irq_desc(irq)->handler = &iic_pic;
+        get_irq_desc(irq)->chip = &iic_pic;
         get_irq_desc(irq)->status |= IRQ_PER_CPU;
         request_irq(irq, iic_ipi_action, SA_INTERRUPT, name, NULL);
 }
@@ -330,7 +330,7 @@ static void iic_setup_spe_handlers(void)
         for (be=0; be < num_present_cpus() / 2; be++) {
                 for (isrc = 0; isrc < IIC_CLASS_STRIDE * 3; isrc++) {
                         int irq = IIC_NODE_STRIDE * be + IIC_SPE_OFFSET + isrc;
-                        get_irq_desc(irq)->handler = &iic_pic;
+                        get_irq_desc(irq)->chip = &iic_pic;
                 }
         }
 }
diff --git a/arch/powerpc/platforms/cell/spider-pic.c b/arch/powerpc/platforms/cell/spider-pic.c
index 55cbdd77a62d..7c3a0b6d34fd 100644
--- a/arch/powerpc/platforms/cell/spider-pic.c
+++ b/arch/powerpc/platforms/cell/spider-pic.c
@@ -162,7 +162,7 @@ void spider_init_IRQ_hardcoded(void)
                 spider_pics[node] = ioremap(spiderpic, 0x800);
                 for (n = 0; n < IIC_NUM_EXT; n++) {
                         int irq = n + IIC_EXT_OFFSET + node * IIC_NODE_STRIDE;
-                        get_irq_desc(irq)->handler = &spider_pic;
+                        get_irq_desc(irq)->chip = &spider_pic;
                 }
 
                 /* do not mask any interrupts because of level */
@@ -217,7 +217,7 @@ void spider_init_IRQ(void)
 
                 for (n = 0; n < IIC_NUM_EXT; n++) {
                         int irq = n + IIC_EXT_OFFSET + node * IIC_NODE_STRIDE;
-                        get_irq_desc(irq)->handler = &spider_pic;
+                        get_irq_desc(irq)->chip = &spider_pic;
                 }
 
                 /* do not mask any interrupts because of level */
diff --git a/arch/powerpc/platforms/iseries/irq.c b/arch/powerpc/platforms/iseries/irq.c
index 62bbbcf5ded3..33bb4aa0e1e8 100644
--- a/arch/powerpc/platforms/iseries/irq.c
+++ b/arch/powerpc/platforms/iseries/irq.c
@@ -242,9 +242,9 @@ void __init iSeries_activate_IRQs()
         for_each_irq (irq) {
                 irq_desc_t *desc = get_irq_desc(irq);
 
-                if (desc && desc->handler && desc->handler->startup) {
+                if (desc && desc->chip && desc->chip->startup) {
                         spin_lock_irqsave(&desc->lock, flags);
-                        desc->handler->startup(irq);
+                        desc->chip->startup(irq);
                         spin_unlock_irqrestore(&desc->lock, flags);
                 }
         }
@@ -324,7 +324,7 @@ int __init iSeries_allocate_IRQ(HvBusNumber bus,
                 + function;
         virtirq = virt_irq_create_mapping(realirq);
 
-        irq_desc[virtirq].handler = &iSeries_IRQ_handler;
+        irq_desc[virtirq].chip = &iSeries_IRQ_handler;
         return virtirq;
 }
 
diff --git a/arch/powerpc/platforms/powermac/pic.c b/arch/powerpc/platforms/powermac/pic.c
index 18bf3011d1e3..9f6189af6dd6 100644
--- a/arch/powerpc/platforms/powermac/pic.c
+++ b/arch/powerpc/platforms/powermac/pic.c
@@ -446,7 +446,7 @@ static void __init pmac_pic_probe_oldstyle(void)
 
         /* Set the handler for the main PIC */
         for ( i = 0; i < max_real_irqs ; i++ )
-                irq_desc[i].handler = &pmac_pic;
+                irq_desc[i].chip = &pmac_pic;
 
         /* Get addresses of first controller if we have a node for it */
         BUG_ON(of_address_to_resource(master, 0, &r));
@@ -493,7 +493,7 @@ static void __init pmac_pic_probe_oldstyle(void)
         /* Setup handlers for secondary controller and hook cascade irq*/
         if (slave) {
                 for ( i = max_real_irqs ; i < max_irqs ; i++ )
-                        irq_desc[i].handler = &gatwick_pic;
+                        irq_desc[i].chip = &gatwick_pic;
                 setup_irq(irq_cascade, &gatwick_cascade_action);
         }
         printk(KERN_INFO "irq: System has %d possible interrupts\n", max_irqs);
diff --git a/arch/powerpc/platforms/pseries/xics.c b/arch/powerpc/platforms/pseries/xics.c
index b14f9b5c114e..bdc9e26a93cf 100644
--- a/arch/powerpc/platforms/pseries/xics.c
+++ b/arch/powerpc/platforms/pseries/xics.c
@@ -558,7 +558,7 @@ nextnode:
         }
 
         for (i = irq_offset_value(); i < NR_IRQS; ++i)
-                get_irq_desc(i)->handler = &xics_pic;
+                get_irq_desc(i)->chip = &xics_pic;
 
         xics_setup_cpu();
 
@@ -701,9 +701,9 @@ void xics_migrate_irqs_away(void)
                         continue;
 
                 /* We only need to migrate enabled IRQS */
-                if (desc == NULL || desc->handler == NULL
+                if (desc == NULL || desc->chip == NULL
                     || desc->action == NULL
-                    || desc->handler->set_affinity == NULL)
+                    || desc->chip->set_affinity == NULL)
                         continue;
 
                 spin_lock_irqsave(&desc->lock, flags);
@@ -728,7 +728,7 @@ void xics_migrate_irqs_away(void)
                        virq, cpu);
 
                 /* Reset affinity to all cpus */
-                desc->handler->set_affinity(virq, CPU_MASK_ALL);
+                desc->chip->set_affinity(virq, CPU_MASK_ALL);
                 irq_affinity[virq] = CPU_MASK_ALL;
 unlock:
                 spin_unlock_irqrestore(&desc->lock, flags);
diff --git a/arch/powerpc/sysdev/i8259.c b/arch/powerpc/sysdev/i8259.c
index b7ac32fdd776..2bff30f6d635 100644
--- a/arch/powerpc/sysdev/i8259.c
+++ b/arch/powerpc/sysdev/i8259.c
@@ -208,7 +208,7 @@ void __init i8259_init(unsigned long intack_addr, int offset)
         spin_unlock_irqrestore(&i8259_lock, flags);
 
         for (i = 0; i < NUM_ISA_INTERRUPTS; ++i)
-                irq_desc[offset + i].handler = &i8259_pic;
+                irq_desc[offset + i].chip = &i8259_pic;
 
         /* reserve our resources */
         setup_irq(offset + 2, &i8259_irqaction);
diff --git a/arch/powerpc/sysdev/ipic.c b/arch/powerpc/sysdev/ipic.c
index 8f01e0f1d847..46801f5ec03f 100644
--- a/arch/powerpc/sysdev/ipic.c
+++ b/arch/powerpc/sysdev/ipic.c
@@ -472,7 +472,7 @@ void __init ipic_init(phys_addr_t phys_addr,
         ipic_write(primary_ipic->regs, IPIC_SEMSR, temp);
 
         for (i = 0 ; i < NR_IPIC_INTS ; i++) {
-                irq_desc[i+irq_offset].handler = &ipic;
+                irq_desc[i+irq_offset].chip = &ipic;
                 irq_desc[i+irq_offset].status = IRQ_LEVEL;
         }
 
diff --git a/arch/powerpc/sysdev/mpic.c b/arch/powerpc/sysdev/mpic.c
index bffe50d02c99..f4613ee6b7a2 100644
--- a/arch/powerpc/sysdev/mpic.c
+++ b/arch/powerpc/sysdev/mpic.c
@@ -379,14 +379,14 @@ static inline u32 mpic_physmask(u32 cpumask)
 /* Get the mpic structure from the IPI number */
 static inline struct mpic * mpic_from_ipi(unsigned int ipi)
 {
-        return container_of(irq_desc[ipi].handler, struct mpic, hc_ipi);
+        return container_of(irq_desc[ipi].chip, struct mpic, hc_ipi);
 }
 #endif
 
 /* Get the mpic structure from the irq number */
 static inline struct mpic * mpic_from_irq(unsigned int irq)
 {
-        return container_of(irq_desc[irq].handler, struct mpic, hc_irq);
+        return container_of(irq_desc[irq].chip, struct mpic, hc_irq);
 }
 
 /* Send an EOI */
@@ -752,7 +752,7 @@ void __init mpic_init(struct mpic *mpic)
                 if (!(mpic->flags & MPIC_PRIMARY))
                         continue;
                 irq_desc[mpic->ipi_offset+i].status |= IRQ_PER_CPU;
-                irq_desc[mpic->ipi_offset+i].handler = &mpic->hc_ipi;
+                irq_desc[mpic->ipi_offset+i].chip = &mpic->hc_ipi;
 #endif /* CONFIG_SMP */
         }
 
@@ -813,7 +813,7 @@ void __init mpic_init(struct mpic *mpic)
                 /* init linux descriptors */
                 if (i < mpic->irq_count) {
                         irq_desc[mpic->irq_offset+i].status = level ? IRQ_LEVEL : 0;
-                        irq_desc[mpic->irq_offset+i].handler = &mpic->hc_irq;
+                        irq_desc[mpic->irq_offset+i].chip = &mpic->hc_irq;
                 }
         }