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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /kernel/irq
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Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'kernel/irq')
-rw-r--r--kernel/irq/Makefile5
-rw-r--r--kernel/irq/autoprobe.c189
-rw-r--r--kernel/irq/handle.c193
-rw-r--r--kernel/irq/internals.h18
-rw-r--r--kernel/irq/manage.c349
-rw-r--r--kernel/irq/proc.c159
-rw-r--r--kernel/irq/spurious.c96
7 files changed, 1009 insertions, 0 deletions
diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile
new file mode 100644
index 000000000000..49378738ff5e
--- /dev/null
+++ b/kernel/irq/Makefile
@@ -0,0 +1,5 @@
+
+obj-y := handle.o manage.o spurious.o
+obj-$(CONFIG_GENERIC_IRQ_PROBE) += autoprobe.o
+obj-$(CONFIG_PROC_FS) += proc.o
+
diff --git a/kernel/irq/autoprobe.c b/kernel/irq/autoprobe.c
new file mode 100644
index 000000000000..98d62d8efeaf
--- /dev/null
+++ b/kernel/irq/autoprobe.c
@@ -0,0 +1,189 @@
+/*
+ * linux/kernel/irq/autoprobe.c
+ *
+ * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
+ *
+ * This file contains the interrupt probing code and driver APIs.
+ */
+
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+
+/*
+ * Autodetection depends on the fact that any interrupt that
+ * comes in on to an unassigned handler will get stuck with
+ * "IRQ_WAITING" cleared and the interrupt disabled.
+ */
+static DECLARE_MUTEX(probe_sem);
+
+/**
+ * probe_irq_on - begin an interrupt autodetect
+ *
+ * Commence probing for an interrupt. The interrupts are scanned
+ * and a mask of potential interrupt lines is returned.
+ *
+ */
+unsigned long probe_irq_on(void)
+{
+ unsigned long val, delay;
+ irq_desc_t *desc;
+ unsigned int i;
+
+ down(&probe_sem);
+ /*
+ * something may have generated an irq long ago and we want to
+ * flush such a longstanding irq before considering it as spurious.
+ */
+ for (i = NR_IRQS-1; i > 0; i--) {
+ desc = irq_desc + i;
+
+ spin_lock_irq(&desc->lock);
+ if (!irq_desc[i].action)
+ irq_desc[i].handler->startup(i);
+ spin_unlock_irq(&desc->lock);
+ }
+
+ /* Wait for longstanding interrupts to trigger. */
+ for (delay = jiffies + HZ/50; time_after(delay, jiffies); )
+ /* about 20ms delay */ barrier();
+
+ /*
+ * enable any unassigned irqs
+ * (we must startup again here because if a longstanding irq
+ * happened in the previous stage, it may have masked itself)
+ */
+ for (i = NR_IRQS-1; i > 0; i--) {
+ desc = irq_desc + i;
+
+ spin_lock_irq(&desc->lock);
+ if (!desc->action) {
+ desc->status |= IRQ_AUTODETECT | IRQ_WAITING;
+ if (desc->handler->startup(i))
+ desc->status |= IRQ_PENDING;
+ }
+ spin_unlock_irq(&desc->lock);
+ }
+
+ /*
+ * Wait for spurious interrupts to trigger
+ */
+ for (delay = jiffies + HZ/10; time_after(delay, jiffies); )
+ /* about 100ms delay */ barrier();
+
+ /*
+ * Now filter out any obviously spurious interrupts
+ */
+ val = 0;
+ for (i = 0; i < NR_IRQS; i++) {
+ irq_desc_t *desc = irq_desc + i;
+ unsigned int status;
+
+ spin_lock_irq(&desc->lock);
+ status = desc->status;
+
+ if (status & IRQ_AUTODETECT) {
+ /* It triggered already - consider it spurious. */
+ if (!(status & IRQ_WAITING)) {
+ desc->status = status & ~IRQ_AUTODETECT;
+ desc->handler->shutdown(i);
+ } else
+ if (i < 32)
+ val |= 1 << i;
+ }
+ spin_unlock_irq(&desc->lock);
+ }
+
+ return val;
+}
+
+EXPORT_SYMBOL(probe_irq_on);
+
+/**
+ * probe_irq_mask - scan a bitmap of interrupt lines
+ * @val: mask of interrupts to consider
+ *
+ * Scan the interrupt lines and return a bitmap of active
+ * autodetect interrupts. The interrupt probe logic state
+ * is then returned to its previous value.
+ *
+ * Note: we need to scan all the irq's even though we will
+ * only return autodetect irq numbers - just so that we reset
+ * them all to a known state.
+ */
+unsigned int probe_irq_mask(unsigned long val)
+{
+ unsigned int mask;
+ int i;
+
+ mask = 0;
+ for (i = 0; i < NR_IRQS; i++) {
+ irq_desc_t *desc = irq_desc + i;
+ unsigned int status;
+
+ spin_lock_irq(&desc->lock);
+ status = desc->status;
+
+ if (status & IRQ_AUTODETECT) {
+ if (i < 16 && !(status & IRQ_WAITING))
+ mask |= 1 << i;
+
+ desc->status = status & ~IRQ_AUTODETECT;
+ desc->handler->shutdown(i);
+ }
+ spin_unlock_irq(&desc->lock);
+ }
+ up(&probe_sem);
+
+ return mask & val;
+}
+EXPORT_SYMBOL(probe_irq_mask);
+
+/**
+ * probe_irq_off - end an interrupt autodetect
+ * @val: mask of potential interrupts (unused)
+ *
+ * Scans the unused interrupt lines and returns the line which
+ * appears to have triggered the interrupt. If no interrupt was
+ * found then zero is returned. If more than one interrupt is
+ * found then minus the first candidate is returned to indicate
+ * their is doubt.
+ *
+ * The interrupt probe logic state is returned to its previous
+ * value.
+ *
+ * BUGS: When used in a module (which arguably shouldn't happen)
+ * nothing prevents two IRQ probe callers from overlapping. The
+ * results of this are non-optimal.
+ */
+int probe_irq_off(unsigned long val)
+{
+ int i, irq_found = 0, nr_irqs = 0;
+
+ for (i = 0; i < NR_IRQS; i++) {
+ irq_desc_t *desc = irq_desc + i;
+ unsigned int status;
+
+ spin_lock_irq(&desc->lock);
+ status = desc->status;
+
+ if (status & IRQ_AUTODETECT) {
+ if (!(status & IRQ_WAITING)) {
+ if (!nr_irqs)
+ irq_found = i;
+ nr_irqs++;
+ }
+ desc->status = status & ~IRQ_AUTODETECT;
+ desc->handler->shutdown(i);
+ }
+ spin_unlock_irq(&desc->lock);
+ }
+ up(&probe_sem);
+
+ if (nr_irqs > 1)
+ irq_found = -irq_found;
+ return irq_found;
+}
+
+EXPORT_SYMBOL(probe_irq_off);
+
diff --git a/kernel/irq/handle.c b/kernel/irq/handle.c
new file mode 100644
index 000000000000..2fb0e46e11f3
--- /dev/null
+++ b/kernel/irq/handle.c
@@ -0,0 +1,193 @@
+/*
+ * linux/kernel/irq/handle.c
+ *
+ * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
+ *
+ * This file contains the core interrupt handling code.
+ */
+
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/random.h>
+#include <linux/interrupt.h>
+#include <linux/kernel_stat.h>
+
+#include "internals.h"
+
+/*
+ * Linux has a controller-independent interrupt architecture.
+ * Every controller has a 'controller-template', that is used
+ * by the main code to do the right thing. Each driver-visible
+ * interrupt source is transparently wired to the apropriate
+ * controller. Thus drivers need not be aware of the
+ * interrupt-controller.
+ *
+ * The code is designed to be easily extended with new/different
+ * interrupt controllers, without having to do assembly magic or
+ * having to touch the generic code.
+ *
+ * Controller mappings for all interrupt sources:
+ */
+irq_desc_t irq_desc[NR_IRQS] __cacheline_aligned = {
+ [0 ... NR_IRQS-1] = {
+ .handler = &no_irq_type,
+ .lock = SPIN_LOCK_UNLOCKED
+ }
+};
+
+/*
+ * Generic 'no controller' code
+ */
+static void end_none(unsigned int irq) { }
+static void enable_none(unsigned int irq) { }
+static void disable_none(unsigned int irq) { }
+static void shutdown_none(unsigned int irq) { }
+static unsigned int startup_none(unsigned int irq) { return 0; }
+
+static void ack_none(unsigned int irq)
+{
+ /*
+ * 'what should we do if we get a hw irq event on an illegal vector'.
+ * each architecture has to answer this themself.
+ */
+ ack_bad_irq(irq);
+}
+
+struct hw_interrupt_type no_irq_type = {
+ .typename = "none",
+ .startup = startup_none,
+ .shutdown = shutdown_none,
+ .enable = enable_none,
+ .disable = disable_none,
+ .ack = ack_none,
+ .end = end_none,
+ .set_affinity = NULL
+};
+
+/*
+ * Special, empty irq handler:
+ */
+irqreturn_t no_action(int cpl, void *dev_id, struct pt_regs *regs)
+{
+ return IRQ_NONE;
+}
+
+/*
+ * Have got an event to handle:
+ */
+fastcall int handle_IRQ_event(unsigned int irq, struct pt_regs *regs,
+ struct irqaction *action)
+{
+ int ret, retval = 0, status = 0;
+
+ if (!(action->flags & SA_INTERRUPT))
+ local_irq_enable();
+
+ do {
+ ret = action->handler(irq, action->dev_id, regs);
+ if (ret == IRQ_HANDLED)
+ status |= action->flags;
+ retval |= ret;
+ action = action->next;
+ } while (action);
+
+ if (status & SA_SAMPLE_RANDOM)
+ add_interrupt_randomness(irq);
+ local_irq_disable();
+
+ return retval;
+}
+
+/*
+ * do_IRQ handles all normal device IRQ's (the special
+ * SMP cross-CPU interrupts have their own specific
+ * handlers).
+ */
+fastcall unsigned int __do_IRQ(unsigned int irq, struct pt_regs *regs)
+{
+ irq_desc_t *desc = irq_desc + irq;
+ struct irqaction * action;
+ unsigned int status;
+
+ kstat_this_cpu.irqs[irq]++;
+ if (desc->status & IRQ_PER_CPU) {
+ irqreturn_t action_ret;
+
+ /*
+ * No locking required for CPU-local interrupts:
+ */
+ desc->handler->ack(irq);
+ action_ret = handle_IRQ_event(irq, regs, desc->action);
+ if (!noirqdebug)
+ note_interrupt(irq, desc, action_ret);
+ desc->handler->end(irq);
+ return 1;
+ }
+
+ spin_lock(&desc->lock);
+ desc->handler->ack(irq);
+ /*
+ * REPLAY is when Linux resends an IRQ that was dropped earlier
+ * WAITING is used by probe to mark irqs that are being tested
+ */
+ status = desc->status & ~(IRQ_REPLAY | IRQ_WAITING);
+ status |= IRQ_PENDING; /* we _want_ to handle it */
+
+ /*
+ * If the IRQ is disabled for whatever reason, we cannot
+ * use the action we have.
+ */
+ action = NULL;
+ if (likely(!(status & (IRQ_DISABLED | IRQ_INPROGRESS)))) {
+ action = desc->action;
+ status &= ~IRQ_PENDING; /* we commit to handling */
+ status |= IRQ_INPROGRESS; /* we are handling it */
+ }
+ desc->status = status;
+
+ /*
+ * If there is no IRQ handler or it was disabled, exit early.
+ * Since we set PENDING, if another processor is handling
+ * a different instance of this same irq, the other processor
+ * will take care of it.
+ */
+ if (unlikely(!action))
+ goto out;
+
+ /*
+ * Edge triggered interrupts need to remember
+ * pending events.
+ * This applies to any hw interrupts that allow a second
+ * instance of the same irq to arrive while we are in do_IRQ
+ * or in the handler. But the code here only handles the _second_
+ * instance of the irq, not the third or fourth. So it is mostly
+ * useful for irq hardware that does not mask cleanly in an
+ * SMP environment.
+ */
+ for (;;) {
+ irqreturn_t action_ret;
+
+ spin_unlock(&desc->lock);
+
+ action_ret = handle_IRQ_event(irq, regs, action);
+
+ spin_lock(&desc->lock);
+ if (!noirqdebug)
+ note_interrupt(irq, desc, action_ret);
+ if (likely(!(desc->status & IRQ_PENDING)))
+ break;
+ desc->status &= ~IRQ_PENDING;
+ }
+ desc->status &= ~IRQ_INPROGRESS;
+
+out:
+ /*
+ * The ->end() handler has to deal with interrupts which got
+ * disabled while the handler was running.
+ */
+ desc->handler->end(irq);
+ spin_unlock(&desc->lock);
+
+ return 1;
+}
+
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
new file mode 100644
index 000000000000..46feba630266
--- /dev/null
+++ b/kernel/irq/internals.h
@@ -0,0 +1,18 @@
+/*
+ * IRQ subsystem internal functions and variables:
+ */
+
+extern int noirqdebug;
+
+#ifdef CONFIG_PROC_FS
+extern void register_irq_proc(unsigned int irq);
+extern void register_handler_proc(unsigned int irq, struct irqaction *action);
+extern void unregister_handler_proc(unsigned int irq, struct irqaction *action);
+#else
+static inline void register_irq_proc(unsigned int irq) { }
+static inline void register_handler_proc(unsigned int irq,
+ struct irqaction *action) { }
+static inline void unregister_handler_proc(unsigned int irq,
+ struct irqaction *action) { }
+#endif
+
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
new file mode 100644
index 000000000000..5202e4c4a5b6
--- /dev/null
+++ b/kernel/irq/manage.c
@@ -0,0 +1,349 @@
+/*
+ * linux/kernel/irq/manage.c
+ *
+ * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
+ *
+ * This file contains driver APIs to the irq subsystem.
+ */
+
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/random.h>
+#include <linux/interrupt.h>
+
+#include "internals.h"
+
+#ifdef CONFIG_SMP
+
+cpumask_t irq_affinity[NR_IRQS] = { [0 ... NR_IRQS-1] = CPU_MASK_ALL };
+
+/**
+ * synchronize_irq - wait for pending IRQ handlers (on other CPUs)
+ *
+ * This function waits for any pending IRQ handlers for this interrupt
+ * to complete before returning. If you use this function while
+ * holding a resource the IRQ handler may need you will deadlock.
+ *
+ * This function may be called - with care - from IRQ context.
+ */
+void synchronize_irq(unsigned int irq)
+{
+ struct irq_desc *desc = irq_desc + irq;
+
+ while (desc->status & IRQ_INPROGRESS)
+ cpu_relax();
+}
+
+EXPORT_SYMBOL(synchronize_irq);
+
+#endif
+
+/**
+ * disable_irq_nosync - disable an irq without waiting
+ * @irq: Interrupt to disable
+ *
+ * Disable the selected interrupt line. Disables and Enables are
+ * nested.
+ * Unlike disable_irq(), this function does not ensure existing
+ * instances of the IRQ handler have completed before returning.
+ *
+ * This function may be called from IRQ context.
+ */
+void disable_irq_nosync(unsigned int irq)
+{
+ irq_desc_t *desc = irq_desc + irq;
+ unsigned long flags;
+
+ spin_lock_irqsave(&desc->lock, flags);
+ if (!desc->depth++) {
+ desc->status |= IRQ_DISABLED;
+ desc->handler->disable(irq);
+ }
+ spin_unlock_irqrestore(&desc->lock, flags);
+}
+
+EXPORT_SYMBOL(disable_irq_nosync);
+
+/**
+ * disable_irq - disable an irq and wait for completion
+ * @irq: Interrupt to disable
+ *
+ * Disable the selected interrupt line. Enables and Disables are
+ * nested.
+ * This function waits for any pending IRQ handlers for this interrupt
+ * to complete before returning. If you use this function while
+ * holding a resource the IRQ handler may need you will deadlock.
+ *
+ * This function may be called - with care - from IRQ context.
+ */
+void disable_irq(unsigned int irq)
+{
+ irq_desc_t *desc = irq_desc + irq;
+
+ disable_irq_nosync(irq);
+ if (desc->action)
+ synchronize_irq(irq);
+}
+
+EXPORT_SYMBOL(disable_irq);
+
+/**
+ * enable_irq - enable handling of an irq
+ * @irq: Interrupt to enable
+ *
+ * Undoes the effect of one call to disable_irq(). If this
+ * matches the last disable, processing of interrupts on this
+ * IRQ line is re-enabled.
+ *
+ * This function may be called from IRQ context.
+ */
+void enable_irq(unsigned int irq)
+{
+ irq_desc_t *desc = irq_desc + irq;
+ unsigned long flags;
+
+ spin_lock_irqsave(&desc->lock, flags);
+ switch (desc->depth) {
+ case 0:
+ WARN_ON(1);
+ break;
+ case 1: {
+ unsigned int status = desc->status & ~IRQ_DISABLED;
+
+ desc->status = status;
+ if ((status & (IRQ_PENDING | IRQ_REPLAY)) == IRQ_PENDING) {
+ desc->status = status | IRQ_REPLAY;
+ hw_resend_irq(desc->handler,irq);
+ }
+ desc->handler->enable(irq);
+ /* fall-through */
+ }
+ default:
+ desc->depth--;
+ }
+ spin_unlock_irqrestore(&desc->lock, flags);
+}
+
+EXPORT_SYMBOL(enable_irq);
+
+/*
+ * Internal function that tells the architecture code whether a
+ * particular irq has been exclusively allocated or is available
+ * for driver use.
+ */
+int can_request_irq(unsigned int irq, unsigned long irqflags)
+{
+ struct irqaction *action;
+
+ if (irq >= NR_IRQS)
+ return 0;
+
+ action = irq_desc[irq].action;
+ if (action)
+ if (irqflags & action->flags & SA_SHIRQ)
+ action = NULL;
+
+ return !action;
+}
+
+/*
+ * Internal function to register an irqaction - typically used to
+ * allocate special interrupts that are part of the architecture.
+ */
+int setup_irq(unsigned int irq, struct irqaction * new)
+{
+ struct irq_desc *desc = irq_desc + irq;
+ struct irqaction *old, **p;
+ unsigned long flags;
+ int shared = 0;
+
+ if (desc->handler == &no_irq_type)
+ return -ENOSYS;
+ /*
+ * Some drivers like serial.c use request_irq() heavily,
+ * so we have to be careful not to interfere with a
+ * running system.
+ */
+ if (new->flags & SA_SAMPLE_RANDOM) {
+ /*
+ * This function might sleep, we want to call it first,
+ * outside of the atomic block.
+ * Yes, this might clear the entropy pool if the wrong
+ * driver is attempted to be loaded, without actually
+ * installing a new handler, but is this really a problem,
+ * only the sysadmin is able to do this.
+ */
+ rand_initialize_irq(irq);
+ }
+
+ /*
+ * The following block of code has to be executed atomically
+ */
+ spin_lock_irqsave(&desc->lock,flags);
+ p = &desc->action;
+ if ((old = *p) != NULL) {
+ /* Can't share interrupts unless both agree to */
+ if (!(old->flags & new->flags & SA_SHIRQ)) {
+ spin_unlock_irqrestore(&desc->lock,flags);
+ return -EBUSY;
+ }
+
+ /* add new interrupt at end of irq queue */
+ do {
+ p = &old->next;
+ old = *p;
+ } while (old);
+ shared = 1;
+ }
+
+ *p = new;
+
+ if (!shared) {
+ desc->depth = 0;
+ desc->status &= ~(IRQ_DISABLED | IRQ_AUTODETECT |
+ IRQ_WAITING | IRQ_INPROGRESS);
+ if (desc->handler->startup)
+ desc->handler->startup(irq);
+ else
+ desc->handler->enable(irq);
+ }
+ spin_unlock_irqrestore(&desc->lock,flags);
+
+ new->irq = irq;
+ register_irq_proc(irq);
+ new->dir = NULL;
+ register_handler_proc(irq, new);
+
+ return 0;
+}
+
+/**
+ * free_irq - free an interrupt
+ * @irq: Interrupt line to free
+ * @dev_id: Device identity to free
+ *
+ * Remove an interrupt handler. The handler is removed and if the
+ * interrupt line is no longer in use by any driver it is disabled.
+ * On a shared IRQ the caller must ensure the interrupt is disabled
+ * on the card it drives before calling this function. The function
+ * does not return until any executing interrupts for this IRQ
+ * have completed.
+ *
+ * This function must not be called from interrupt context.
+ */
+void free_irq(unsigned int irq, void *dev_id)
+{
+ struct irq_desc *desc;
+ struct irqaction **p;
+ unsigned long flags;
+
+ if (irq >= NR_IRQS)
+ return;
+
+ desc = irq_desc + irq;
+ spin_lock_irqsave(&desc->lock,flags);
+ p = &desc->action;
+ for (;;) {
+ struct irqaction * action = *p;
+
+ if (action) {
+ struct irqaction **pp = p;
+
+ p = &action->next;
+ if (action->dev_id != dev_id)
+ continue;
+
+ /* Found it - now remove it from the list of entries */
+ *pp = action->next;
+ if (!desc->action) {
+ desc->status |= IRQ_DISABLED;
+ if (desc->handler->shutdown)
+ desc->handler->shutdown(irq);
+ else
+ desc->handler->disable(irq);
+ }
+ spin_unlock_irqrestore(&desc->lock,flags);
+ unregister_handler_proc(irq, action);
+
+ /* Make sure it's not being used on another CPU */
+ synchronize_irq(irq);
+ kfree(action);
+ return;
+ }
+ printk(KERN_ERR "Trying to free free IRQ%d\n",irq);
+ spin_unlock_irqrestore(&desc->lock,flags);
+ return;
+ }
+}
+
+EXPORT_SYMBOL(free_irq);
+
+/**
+ * request_irq - allocate an interrupt line
+ * @irq: Interrupt line to allocate
+ * @handler: Function to be called when the IRQ occurs
+ * @irqflags: Interrupt type flags
+ * @devname: An ascii name for the claiming device
+ * @dev_id: A cookie passed back to the handler function
+ *
+ * This call allocates interrupt resources and enables the
+ * interrupt line and IRQ handling. From the point this
+ * call is made your handler function may be invoked. Since
+ * your handler function must clear any interrupt the board
+ * raises, you must take care both to initialise your hardware
+ * and to set up the interrupt handler in the right order.
+ *
+ * Dev_id must be globally unique. Normally the address of the
+ * device data structure is used as the cookie. Since the handler
+ * receives this value it makes sense to use it.
+ *
+ * If your interrupt is shared you must pass a non NULL dev_id
+ * as this is required when freeing the interrupt.
+ *
+ * Flags:
+ *
+ * SA_SHIRQ Interrupt is shared
+ * SA_INTERRUPT Disable local interrupts while processing
+ * SA_SAMPLE_RANDOM The interrupt can be used for entropy
+ *
+ */
+int request_irq(unsigned int irq,
+ irqreturn_t (*handler)(int, void *, struct pt_regs *),
+ unsigned long irqflags, const char * devname, void *dev_id)
+{
+ struct irqaction * action;
+ int retval;
+
+ /*
+ * Sanity-check: shared interrupts must pass in a real dev-ID,
+ * otherwise we'll have trouble later trying to figure out
+ * which interrupt is which (messes up the interrupt freeing
+ * logic etc).
+ */
+ if ((irqflags & SA_SHIRQ) && !dev_id)
+ return -EINVAL;
+ if (irq >= NR_IRQS)
+ return -EINVAL;
+ if (!handler)
+ return -EINVAL;
+
+ action = kmalloc(sizeof(struct irqaction), GFP_ATOMIC);
+ if (!action)
+ return -ENOMEM;
+
+ action->handler = handler;
+ action->flags = irqflags;
+ cpus_clear(action->mask);
+ action->name = devname;
+ action->next = NULL;
+ action->dev_id = dev_id;
+
+ retval = setup_irq(irq, action);
+ if (retval)
+ kfree(action);
+
+ return retval;
+}
+
+EXPORT_SYMBOL(request_irq);
+
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
new file mode 100644
index 000000000000..85d08daa6600
--- /dev/null
+++ b/kernel/irq/proc.c
@@ -0,0 +1,159 @@
+/*
+ * linux/kernel/irq/proc.c
+ *
+ * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
+ *
+ * This file contains the /proc/irq/ handling code.
+ */
+
+#include <linux/irq.h>
+#include <linux/proc_fs.h>
+#include <linux/interrupt.h>
+
+static struct proc_dir_entry *root_irq_dir, *irq_dir[NR_IRQS];
+
+#ifdef CONFIG_SMP
+
+/*
+ * The /proc/irq/<irq>/smp_affinity values:
+ */
+static struct proc_dir_entry *smp_affinity_entry[NR_IRQS];
+
+void __attribute__((weak))
+proc_set_irq_affinity(unsigned int irq, cpumask_t mask_val)
+{
+ irq_affinity[irq] = mask_val;
+ irq_desc[irq].handler->set_affinity(irq, mask_val);
+}
+
+static int irq_affinity_read_proc(char *page, char **start, off_t off,
+ int count, int *eof, void *data)
+{
+ int len = cpumask_scnprintf(page, count, irq_affinity[(long)data]);
+
+ if (count - len < 2)
+ return -EINVAL;
+ len += sprintf(page + len, "\n");
+ return len;
+}
+
+int no_irq_affinity;
+static int irq_affinity_write_proc(struct file *file, const char __user *buffer,
+ unsigned long count, void *data)
+{
+ unsigned int irq = (int)(long)data, full_count = count, err;
+ cpumask_t new_value, tmp;
+
+ if (!irq_desc[irq].handler->set_affinity || no_irq_affinity)
+ return -EIO;
+
+ err = cpumask_parse(buffer, count, new_value);
+ if (err)
+ return err;
+
+ /*
+ * Do not allow disabling IRQs completely - it's a too easy
+ * way to make the system unusable accidentally :-) At least
+ * one online CPU still has to be targeted.
+ */
+ cpus_and(tmp, new_value, cpu_online_map);
+ if (cpus_empty(tmp))
+ return -EINVAL;
+
+ proc_set_irq_affinity(irq, new_value);
+
+ return full_count;
+}
+
+#endif
+
+#define MAX_NAMELEN 128
+
+static int name_unique(unsigned int irq, struct irqaction *new_action)
+{
+ struct irq_desc *desc = irq_desc + irq;
+ struct irqaction *action;
+
+ for (action = desc->action ; action; action = action->next)
+ if ((action != new_action) && action->name &&
+ !strcmp(new_action->name, action->name))
+ return 0;
+ return 1;
+}
+
+void register_handler_proc(unsigned int irq, struct irqaction *action)
+{
+ char name [MAX_NAMELEN];
+
+ if (!irq_dir[irq] || action->dir || !action->name ||
+ !name_unique(irq, action))
+ return;
+
+ memset(name, 0, MAX_NAMELEN);
+ snprintf(name, MAX_NAMELEN, "%s", action->name);
+
+ /* create /proc/irq/1234/handler/ */
+ action->dir = proc_mkdir(name, irq_dir[irq]);
+}
+
+#undef MAX_NAMELEN
+
+#define MAX_NAMELEN 10
+
+void register_irq_proc(unsigned int irq)
+{
+ char name [MAX_NAMELEN];
+
+ if (!root_irq_dir ||
+ (irq_desc[irq].handler == &no_irq_type) ||
+ irq_dir[irq])
+ return;
+
+ memset(name, 0, MAX_NAMELEN);
+ sprintf(name, "%d", irq);
+
+ /* create /proc/irq/1234 */
+ irq_dir[irq] = proc_mkdir(name, root_irq_dir);
+
+#ifdef CONFIG_SMP
+ {
+ struct proc_dir_entry *entry;
+
+ /* create /proc/irq/<irq>/smp_affinity */
+ entry = create_proc_entry("smp_affinity", 0600, irq_dir[irq]);
+
+ if (entry) {
+ entry->nlink = 1;
+ entry->data = (void *)(long)irq;
+ entry->read_proc = irq_affinity_read_proc;
+ entry->write_proc = irq_affinity_write_proc;
+ }
+ smp_affinity_entry[irq] = entry;
+ }
+#endif
+}
+
+#undef MAX_NAMELEN
+
+void unregister_handler_proc(unsigned int irq, struct irqaction *action)
+{
+ if (action->dir)
+ remove_proc_entry(action->dir->name, irq_dir[irq]);
+}
+
+void init_irq_proc(void)
+{
+ int i;
+
+ /* create /proc/irq */
+ root_irq_dir = proc_mkdir("irq", NULL);
+ if (!root_irq_dir)
+ return;
+
+ /*
+ * Create entries for all existing IRQs.
+ */
+ for (i = 0; i < NR_IRQS; i++)
+ register_irq_proc(i);
+}
+
diff --git a/kernel/irq/spurious.c b/kernel/irq/spurious.c
new file mode 100644
index 000000000000..f6297c306905
--- /dev/null
+++ b/kernel/irq/spurious.c
@@ -0,0 +1,96 @@
+/*
+ * linux/kernel/irq/spurious.c
+ *
+ * Copyright (C) 1992, 1998-2004 Linus Torvalds, Ingo Molnar
+ *
+ * This file contains spurious interrupt handling.
+ */
+
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/kallsyms.h>
+#include <linux/interrupt.h>
+
+/*
+ * If 99,900 of the previous 100,000 interrupts have not been handled
+ * then assume that the IRQ is stuck in some manner. Drop a diagnostic
+ * and try to turn the IRQ off.
+ *
+ * (The other 100-of-100,000 interrupts may have been a correctly
+ * functioning device sharing an IRQ with the failing one)
+ *
+ * Called under desc->lock
+ */
+
+static void
+__report_bad_irq(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret)
+{
+ struct irqaction *action;
+
+ if (action_ret != IRQ_HANDLED && action_ret != IRQ_NONE) {
+ printk(KERN_ERR "irq event %d: bogus return value %x\n",
+ irq, action_ret);
+ } else {
+ printk(KERN_ERR "irq %d: nobody cared!\n", irq);
+ }
+ dump_stack();
+ printk(KERN_ERR "handlers:\n");
+ action = desc->action;
+ while (action) {
+ printk(KERN_ERR "[<%p>]", action->handler);
+ print_symbol(" (%s)",
+ (unsigned long)action->handler);
+ printk("\n");
+ action = action->next;
+ }
+}
+
+void report_bad_irq(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret)
+{
+ static int count = 100;
+
+ if (count > 0) {
+ count--;
+ __report_bad_irq(irq, desc, action_ret);
+ }
+}
+
+void note_interrupt(unsigned int irq, irq_desc_t *desc, irqreturn_t action_ret)
+{
+ if (action_ret != IRQ_HANDLED) {
+ desc->irqs_unhandled++;
+ if (action_ret != IRQ_NONE)
+ report_bad_irq(irq, desc, action_ret);
+ }
+
+ desc->irq_count++;
+ if (desc->irq_count < 100000)
+ return;
+
+ desc->irq_count = 0;
+ if (desc->irqs_unhandled > 99900) {
+ /*
+ * The interrupt is stuck
+ */
+ __report_bad_irq(irq, desc, action_ret);
+ /*
+ * Now kill the IRQ
+ */
+ printk(KERN_EMERG "Disabling IRQ #%d\n", irq);
+ desc->status |= IRQ_DISABLED;
+ desc->handler->disable(irq);
+ }
+ desc->irqs_unhandled = 0;
+}
+
+int noirqdebug;
+
+int __init noirqdebug_setup(char *str)
+{
+ noirqdebug = 1;
+ printk(KERN_INFO "IRQ lockup detection disabled\n");
+ return 1;
+}
+
+__setup("noirqdebug", noirqdebug_setup);
+