*/
#include <linux/irq.h>
+#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/random.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
+#include <linux/sched.h>
#include "internals.h"
-#ifdef CONFIG_SMP
-
-cpumask_t irq_default_affinity = CPU_MASK_ALL;
-
/**
* synchronize_irq - wait for pending IRQ handlers (on other CPUs)
* @irq: interrupt number to wait for
cpu_relax();
/* Ok, that indicated we're done: double-check carefully. */
- spin_lock_irqsave(&desc->lock, flags);
+ raw_spin_lock_irqsave(&desc->lock, flags);
status = desc->status;
- spin_unlock_irqrestore(&desc->lock, flags);
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
/* Oops, that failed? */
} while (status & IRQ_INPROGRESS);
+
+ /*
+ * We made sure that no hardirq handler is running. Now verify
+ * that no threaded handlers are active.
+ */
+ wait_event(desc->wait_for_threads, !atomic_read(&desc->threads_active));
}
EXPORT_SYMBOL(synchronize_irq);
+#ifdef CONFIG_SMP
+cpumask_var_t irq_default_affinity;
+
/**
* irq_can_set_affinity - Check if the affinity of a given irq can be set
* @irq: Interrupt to check
}
/**
+ * irq_set_thread_affinity - Notify irq threads to adjust affinity
+ * @desc: irq descriptor which has affitnity changed
+ *
+ * We just set IRQTF_AFFINITY and delegate the affinity setting
+ * to the interrupt thread itself. We can not call
+ * set_cpus_allowed_ptr() here as we hold desc->lock and this
+ * code can be called from hard interrupt context.
+ */
+void irq_set_thread_affinity(struct irq_desc *desc)
+{
+ struct irqaction *action = desc->action;
+
+ while (action) {
+ if (action->thread)
+ set_bit(IRQTF_AFFINITY, &action->thread_flags);
+ action = action->next;
+ }
+}
+
+/**
* irq_set_affinity - Set the irq affinity of a given irq
* @irq: Interrupt to set affinity
* @cpumask: cpumask
*
*/
-int irq_set_affinity(unsigned int irq, cpumask_t cpumask)
+int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
{
struct irq_desc *desc = irq_to_desc(irq);
unsigned long flags;
if (!desc->chip->set_affinity)
return -EINVAL;
- spin_lock_irqsave(&desc->lock, flags);
+ raw_spin_lock_irqsave(&desc->lock, flags);
#ifdef CONFIG_GENERIC_PENDING_IRQ
- if (desc->status & IRQ_MOVE_PCNTXT || desc->status & IRQ_DISABLED) {
- desc->affinity = cpumask;
- desc->chip->set_affinity(irq, cpumask);
- } else {
+ if (desc->status & IRQ_MOVE_PCNTXT) {
+ if (!desc->chip->set_affinity(irq, cpumask)) {
+ cpumask_copy(desc->affinity, cpumask);
+ irq_set_thread_affinity(desc);
+ }
+ }
+ else {
desc->status |= IRQ_MOVE_PENDING;
- desc->pending_mask = cpumask;
+ cpumask_copy(desc->pending_mask, cpumask);
}
#else
- desc->affinity = cpumask;
- desc->chip->set_affinity(irq, cpumask);
+ if (!desc->chip->set_affinity(irq, cpumask)) {
+ cpumask_copy(desc->affinity, cpumask);
+ irq_set_thread_affinity(desc);
+ }
#endif
desc->status |= IRQ_AFFINITY_SET;
- spin_unlock_irqrestore(&desc->lock, flags);
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+ return 0;
+}
+
+int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+ unsigned long flags;
+
+ if (!desc)
+ return -EINVAL;
+
+ raw_spin_lock_irqsave(&desc->lock, flags);
+ desc->affinity_hint = m;
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+
return 0;
}
+EXPORT_SYMBOL_GPL(irq_set_affinity_hint);
#ifndef CONFIG_AUTO_IRQ_AFFINITY
/*
* Generic version of the affinity autoselector.
*/
-int do_irq_select_affinity(unsigned int irq, struct irq_desc *desc)
+static int setup_affinity(unsigned int irq, struct irq_desc *desc)
{
- cpumask_t mask;
-
if (!irq_can_set_affinity(irq))
return 0;
- cpus_and(mask, cpu_online_map, irq_default_affinity);
-
/*
* Preserve an userspace affinity setup, but make sure that
* one of the targets is online.
*/
if (desc->status & (IRQ_AFFINITY_SET | IRQ_NO_BALANCING)) {
- if (cpus_intersects(desc->affinity, cpu_online_map))
- mask = desc->affinity;
+ if (cpumask_any_and(desc->affinity, cpu_online_mask)
+ < nr_cpu_ids)
+ goto set_affinity;
else
desc->status &= ~IRQ_AFFINITY_SET;
}
- desc->affinity = mask;
- desc->chip->set_affinity(irq, mask);
+ cpumask_and(desc->affinity, cpu_online_mask, irq_default_affinity);
+set_affinity:
+ desc->chip->set_affinity(irq, desc->affinity);
return 0;
}
#else
-static inline int do_irq_select_affinity(unsigned int irq, struct irq_desc *d)
+static inline int setup_affinity(unsigned int irq, struct irq_desc *d)
{
return irq_select_affinity(irq);
}
unsigned long flags;
int ret;
- spin_lock_irqsave(&desc->lock, flags);
- ret = do_irq_select_affinity(irq, desc);
- spin_unlock_irqrestore(&desc->lock, flags);
+ raw_spin_lock_irqsave(&desc->lock, flags);
+ ret = setup_affinity(irq, desc);
+ if (!ret)
+ irq_set_thread_affinity(desc);
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
return ret;
}
#else
-static inline int do_irq_select_affinity(int irq, struct irq_desc *desc)
+static inline int setup_affinity(unsigned int irq, struct irq_desc *desc)
{
return 0;
}
#endif
+void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend)
+{
+ if (suspend) {
+ if (!desc->action || (desc->action->flags & IRQF_TIMER))
+ return;
+ desc->status |= IRQ_SUSPENDED;
+ }
+
+ if (!desc->depth++) {
+ desc->status |= IRQ_DISABLED;
+ desc->chip->disable(irq);
+ }
+}
+
/**
* disable_irq_nosync - disable an irq without waiting
* @irq: Interrupt to disable
if (!desc)
return;
- spin_lock_irqsave(&desc->lock, flags);
- if (!desc->depth++) {
- desc->status |= IRQ_DISABLED;
- desc->chip->disable(irq);
- }
- spin_unlock_irqrestore(&desc->lock, flags);
+ chip_bus_lock(irq, desc);
+ raw_spin_lock_irqsave(&desc->lock, flags);
+ __disable_irq(desc, irq, false);
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+ chip_bus_sync_unlock(irq, desc);
}
EXPORT_SYMBOL(disable_irq_nosync);
}
EXPORT_SYMBOL(disable_irq);
-static void __enable_irq(struct irq_desc *desc, unsigned int irq)
+void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume)
{
+ if (resume)
+ desc->status &= ~IRQ_SUSPENDED;
+
switch (desc->depth) {
case 0:
+ err_out:
WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n", irq);
break;
case 1: {
unsigned int status = desc->status & ~IRQ_DISABLED;
+ if (desc->status & IRQ_SUSPENDED)
+ goto err_out;
/* Prevent probing on this irq: */
desc->status = status | IRQ_NOPROBE;
check_irq_resend(desc, irq);
* matches the last disable, processing of interrupts on this
* IRQ line is re-enabled.
*
- * This function may be called from IRQ context.
+ * This function may be called from IRQ context only when
+ * desc->chip->bus_lock and desc->chip->bus_sync_unlock are NULL !
*/
void enable_irq(unsigned int irq)
{
if (!desc)
return;
- spin_lock_irqsave(&desc->lock, flags);
- __enable_irq(desc, irq);
- spin_unlock_irqrestore(&desc->lock, flags);
+ chip_bus_lock(irq, desc);
+ raw_spin_lock_irqsave(&desc->lock, flags);
+ __enable_irq(desc, irq, false);
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+ chip_bus_sync_unlock(irq, desc);
}
EXPORT_SYMBOL(enable_irq);
/* wakeup-capable irqs can be shared between drivers that
* don't need to have the same sleep mode behaviors.
*/
- spin_lock_irqsave(&desc->lock, flags);
+ raw_spin_lock_irqsave(&desc->lock, flags);
if (on) {
if (desc->wake_depth++ == 0) {
ret = set_irq_wake_real(irq, on);
}
}
- spin_unlock_irqrestore(&desc->lock, flags);
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
return ret;
}
EXPORT_SYMBOL(set_irq_wake);
{
struct irq_desc *desc = irq_to_desc(irq);
struct irqaction *action;
+ unsigned long flags;
if (!desc)
return 0;
if (desc->status & IRQ_NOREQUEST)
return 0;
+ raw_spin_lock_irqsave(&desc->lock, flags);
action = desc->action;
if (action)
if (irqflags & action->flags & IRQF_SHARED)
action = NULL;
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+
return !action;
}
return 0;
}
- ret = chip->set_type(irq, flags & IRQF_TRIGGER_MASK);
+ /* caller masked out all except trigger mode flags */
+ ret = chip->set_type(irq, flags);
if (ret)
pr_err("setting trigger mode %d for irq %u failed (%pF)\n",
- (int)(flags & IRQF_TRIGGER_MASK),
- irq, chip->set_type);
+ (int)flags, irq, chip->set_type);
else {
+ if (flags & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
+ flags |= IRQ_LEVEL;
/* note that IRQF_TRIGGER_MASK == IRQ_TYPE_SENSE_MASK */
- desc->status &= ~IRQ_TYPE_SENSE_MASK;
- desc->status |= flags & IRQ_TYPE_SENSE_MASK;
+ desc->status &= ~(IRQ_LEVEL | IRQ_TYPE_SENSE_MASK);
+ desc->status |= flags;
}
return ret;
}
/*
+ * Default primary interrupt handler for threaded interrupts. Is
+ * assigned as primary handler when request_threaded_irq is called
+ * with handler == NULL. Useful for oneshot interrupts.
+ */
+static irqreturn_t irq_default_primary_handler(int irq, void *dev_id)
+{
+ return IRQ_WAKE_THREAD;
+}
+
+/*
+ * Primary handler for nested threaded interrupts. Should never be
+ * called.
+ */
+static irqreturn_t irq_nested_primary_handler(int irq, void *dev_id)
+{
+ WARN(1, "Primary handler called for nested irq %d\n", irq);
+ return IRQ_NONE;
+}
+
+static int irq_wait_for_interrupt(struct irqaction *action)
+{
+ while (!kthread_should_stop()) {
+ set_current_state(TASK_INTERRUPTIBLE);
+
+ if (test_and_clear_bit(IRQTF_RUNTHREAD,
+ &action->thread_flags)) {
+ __set_current_state(TASK_RUNNING);
+ return 0;
+ }
+ schedule();
+ }
+ return -1;
+}
+
+/*
+ * Oneshot interrupts keep the irq line masked until the threaded
+ * handler finished. unmask if the interrupt has not been disabled and
+ * is marked MASKED.
+ */
+static void irq_finalize_oneshot(unsigned int irq, struct irq_desc *desc)
+{
+again:
+ chip_bus_lock(irq, desc);
+ raw_spin_lock_irq(&desc->lock);
+
+ /*
+ * Implausible though it may be we need to protect us against
+ * the following scenario:
+ *
+ * The thread is faster done than the hard interrupt handler
+ * on the other CPU. If we unmask the irq line then the
+ * interrupt can come in again and masks the line, leaves due
+ * to IRQ_INPROGRESS and the irq line is masked forever.
+ */
+ if (unlikely(desc->status & IRQ_INPROGRESS)) {
+ raw_spin_unlock_irq(&desc->lock);
+ chip_bus_sync_unlock(irq, desc);
+ cpu_relax();
+ goto again;
+ }
+
+ if (!(desc->status & IRQ_DISABLED) && (desc->status & IRQ_MASKED)) {
+ desc->status &= ~IRQ_MASKED;
+ desc->chip->unmask(irq);
+ }
+ raw_spin_unlock_irq(&desc->lock);
+ chip_bus_sync_unlock(irq, desc);
+}
+
+#ifdef CONFIG_SMP
+/*
+ * Check whether we need to change the affinity of the interrupt thread.
+ */
+static void
+irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
+{
+ cpumask_var_t mask;
+
+ if (!test_and_clear_bit(IRQTF_AFFINITY, &action->thread_flags))
+ return;
+
+ /*
+ * In case we are out of memory we set IRQTF_AFFINITY again and
+ * try again next time
+ */
+ if (!alloc_cpumask_var(&mask, GFP_KERNEL)) {
+ set_bit(IRQTF_AFFINITY, &action->thread_flags);
+ return;
+ }
+
+ raw_spin_lock_irq(&desc->lock);
+ cpumask_copy(mask, desc->affinity);
+ raw_spin_unlock_irq(&desc->lock);
+
+ set_cpus_allowed_ptr(current, mask);
+ free_cpumask_var(mask);
+}
+#else
+static inline void
+irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { }
+#endif
+
+/*
+ * Interrupt handler thread
+ */
+static int irq_thread(void *data)
+{
+ struct sched_param param = { .sched_priority = MAX_USER_RT_PRIO/2, };
+ struct irqaction *action = data;
+ struct irq_desc *desc = irq_to_desc(action->irq);
+ int wake, oneshot = desc->status & IRQ_ONESHOT;
+
+ sched_setscheduler(current, SCHED_FIFO, ¶m);
+ current->irqaction = action;
+
+ while (!irq_wait_for_interrupt(action)) {
+
+ irq_thread_check_affinity(desc, action);
+
+ atomic_inc(&desc->threads_active);
+
+ raw_spin_lock_irq(&desc->lock);
+ if (unlikely(desc->status & IRQ_DISABLED)) {
+ /*
+ * CHECKME: We might need a dedicated
+ * IRQ_THREAD_PENDING flag here, which
+ * retriggers the thread in check_irq_resend()
+ * but AFAICT IRQ_PENDING should be fine as it
+ * retriggers the interrupt itself --- tglx
+ */
+ desc->status |= IRQ_PENDING;
+ raw_spin_unlock_irq(&desc->lock);
+ } else {
+ raw_spin_unlock_irq(&desc->lock);
+
+ action->thread_fn(action->irq, action->dev_id);
+
+ if (oneshot)
+ irq_finalize_oneshot(action->irq, desc);
+ }
+
+ wake = atomic_dec_and_test(&desc->threads_active);
+
+ if (wake && waitqueue_active(&desc->wait_for_threads))
+ wake_up(&desc->wait_for_threads);
+ }
+
+ /*
+ * Clear irqaction. Otherwise exit_irq_thread() would make
+ * fuzz about an active irq thread going into nirvana.
+ */
+ current->irqaction = NULL;
+ return 0;
+}
+
+/*
+ * Called from do_exit()
+ */
+void exit_irq_thread(void)
+{
+ struct task_struct *tsk = current;
+
+ if (!tsk->irqaction)
+ return;
+
+ printk(KERN_ERR
+ "exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
+ tsk->comm ? tsk->comm : "", tsk->pid, tsk->irqaction->irq);
+
+ /*
+ * Set the THREAD DIED flag to prevent further wakeups of the
+ * soon to be gone threaded handler.
+ */
+ set_bit(IRQTF_DIED, &tsk->irqaction->flags);
+}
+
+/*
* Internal function to register an irqaction - typically used to
* allocate special interrupts that are part of the architecture.
*/
static int
-__setup_irq(unsigned int irq, struct irq_desc * desc, struct irqaction *new)
+__setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
{
- struct irqaction *old, **p;
+ struct irqaction *old, **old_ptr;
const char *old_name = NULL;
unsigned long flags;
- int shared = 0;
+ int nested, shared = 0;
int ret;
if (!desc)
rand_initialize_irq(irq);
}
+ /* Oneshot interrupts are not allowed with shared */
+ if ((new->flags & IRQF_ONESHOT) && (new->flags & IRQF_SHARED))
+ return -EINVAL;
+
+ /*
+ * Check whether the interrupt nests into another interrupt
+ * thread.
+ */
+ nested = desc->status & IRQ_NESTED_THREAD;
+ if (nested) {
+ if (!new->thread_fn)
+ return -EINVAL;
+ /*
+ * Replace the primary handler which was provided from
+ * the driver for non nested interrupt handling by the
+ * dummy function which warns when called.
+ */
+ new->handler = irq_nested_primary_handler;
+ }
+
+ /*
+ * Create a handler thread when a thread function is supplied
+ * and the interrupt does not nest into another interrupt
+ * thread.
+ */
+ if (new->thread_fn && !nested) {
+ struct task_struct *t;
+
+ t = kthread_create(irq_thread, new, "irq/%d-%s", irq,
+ new->name);
+ if (IS_ERR(t))
+ return PTR_ERR(t);
+ /*
+ * We keep the reference to the task struct even if
+ * the thread dies to avoid that the interrupt code
+ * references an already freed task_struct.
+ */
+ get_task_struct(t);
+ new->thread = t;
+ }
+
/*
* The following block of code has to be executed atomically
*/
- spin_lock_irqsave(&desc->lock, flags);
- p = &desc->action;
- old = *p;
+ raw_spin_lock_irqsave(&desc->lock, flags);
+ old_ptr = &desc->action;
+ old = *old_ptr;
if (old) {
/*
* Can't share interrupts unless both agree to and are
/* add new interrupt at end of irq queue */
do {
- p = &old->next;
- old = *p;
+ old_ptr = &old->next;
+ old = *old_ptr;
} while (old);
shared = 1;
}
if (!shared) {
irq_chip_set_defaults(desc->chip);
+ init_waitqueue_head(&desc->wait_for_threads);
+
/* Setup the type (level, edge polarity) if configured: */
if (new->flags & IRQF_TRIGGER_MASK) {
- ret = __irq_set_trigger(desc, irq, new->flags);
+ ret = __irq_set_trigger(desc, irq,
+ new->flags & IRQF_TRIGGER_MASK);
- if (ret) {
- spin_unlock_irqrestore(&desc->lock, flags);
- return ret;
- }
+ if (ret)
+ goto out_thread;
} else
compat_irq_chip_set_default_handler(desc);
#if defined(CONFIG_IRQ_PER_CPU)
desc->status |= IRQ_PER_CPU;
#endif
- desc->status &= ~(IRQ_AUTODETECT | IRQ_WAITING |
+ desc->status &= ~(IRQ_AUTODETECT | IRQ_WAITING | IRQ_ONESHOT |
IRQ_INPROGRESS | IRQ_SPURIOUS_DISABLED);
+ if (new->flags & IRQF_ONESHOT)
+ desc->status |= IRQ_ONESHOT;
+
if (!(desc->status & IRQ_NOAUTOEN)) {
desc->depth = 0;
desc->status &= ~IRQ_DISABLED;
desc->status |= IRQ_NO_BALANCING;
/* Set default affinity mask once everything is setup */
- do_irq_select_affinity(irq, desc);
+ setup_affinity(irq, desc);
} else if ((new->flags & IRQF_TRIGGER_MASK)
&& (new->flags & IRQF_TRIGGER_MASK)
(int)(new->flags & IRQF_TRIGGER_MASK));
}
- *p = new;
+ new->irq = irq;
+ *old_ptr = new;
/* Reset broken irq detection when installing new handler */
desc->irq_count = 0;
*/
if (shared && (desc->status & IRQ_SPURIOUS_DISABLED)) {
desc->status &= ~IRQ_SPURIOUS_DISABLED;
- __enable_irq(desc, irq);
+ __enable_irq(desc, irq, false);
}
- spin_unlock_irqrestore(&desc->lock, flags);
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+
+ /*
+ * Strictly no need to wake it up, but hung_task complains
+ * when no hard interrupt wakes the thread up.
+ */
+ if (new->thread)
+ wake_up_process(new->thread);
- new->irq = irq;
register_irq_proc(irq, desc);
new->dir = NULL;
register_handler_proc(irq, new);
dump_stack();
}
#endif
- spin_unlock_irqrestore(&desc->lock, flags);
- return -EBUSY;
+ ret = -EBUSY;
+
+out_thread:
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+ if (new->thread) {
+ struct task_struct *t = new->thread;
+
+ new->thread = NULL;
+ if (likely(!test_bit(IRQTF_DIED, &new->thread_flags)))
+ kthread_stop(t);
+ put_task_struct(t);
+ }
+ return ret;
}
/**
return __setup_irq(irq, desc, act);
}
+EXPORT_SYMBOL_GPL(setup_irq);
-/**
- * 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.
+ /*
+ * Internal function to unregister an irqaction - used to free
+ * regular and special interrupts that are part of the architecture.
*/
-void free_irq(unsigned int irq, void *dev_id)
+static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
{
struct irq_desc *desc = irq_to_desc(irq);
- struct irqaction **p;
+ struct irqaction *action, **action_ptr;
unsigned long flags;
- WARN_ON(in_interrupt());
+ WARN(in_interrupt(), "Trying to free IRQ %d from IRQ context!\n", irq);
if (!desc)
- return;
+ return NULL;
- spin_lock_irqsave(&desc->lock, flags);
- p = &desc->action;
+ raw_spin_lock_irqsave(&desc->lock, flags);
+
+ /*
+ * There can be multiple actions per IRQ descriptor, find the right
+ * one based on the dev_id:
+ */
+ action_ptr = &desc->action;
for (;;) {
- struct irqaction *action = *p;
+ action = *action_ptr;
+
+ if (!action) {
+ WARN(1, "Trying to free already-free IRQ %d\n", irq);
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
- if (action) {
- struct irqaction **pp = p;
+ return NULL;
+ }
- p = &action->next;
- if (action->dev_id != dev_id)
- continue;
+ if (action->dev_id == dev_id)
+ break;
+ action_ptr = &action->next;
+ }
- /* Found it - now remove it from the list of entries */
- *pp = action->next;
+ /* Found it - now remove it from the list of entries: */
+ *action_ptr = action->next;
- /* Currently used only by UML, might disappear one day.*/
+ /* Currently used only by UML, might disappear one day: */
#ifdef CONFIG_IRQ_RELEASE_METHOD
- if (desc->chip->release)
- desc->chip->release(irq, dev_id);
+ if (desc->chip->release)
+ desc->chip->release(irq, dev_id);
#endif
- if (!desc->action) {
- desc->status |= IRQ_DISABLED;
- if (desc->chip->shutdown)
- desc->chip->shutdown(irq);
- else
- desc->chip->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);
-#ifdef CONFIG_DEBUG_SHIRQ
- /*
- * It's a shared IRQ -- the driver ought to be
- * prepared for it to happen even now it's
- * being freed, so let's make sure.... We do
- * this after actually deregistering it, to
- * make sure that a 'real' IRQ doesn't run in
- * parallel with our fake
- */
- if (action->flags & IRQF_SHARED) {
- local_irq_save(flags);
- action->handler(irq, dev_id);
- local_irq_restore(flags);
- }
+ /* If this was the last handler, shut down the IRQ line: */
+ if (!desc->action) {
+ desc->status |= IRQ_DISABLED;
+ if (desc->chip->shutdown)
+ desc->chip->shutdown(irq);
+ else
+ desc->chip->disable(irq);
+ }
+
+#ifdef CONFIG_SMP
+ /* make sure affinity_hint is cleaned up */
+ if (WARN_ON_ONCE(desc->affinity_hint))
+ desc->affinity_hint = NULL;
#endif
- kfree(action);
- return;
- }
- printk(KERN_ERR "Trying to free already-free IRQ %d\n", irq);
+
+ raw_spin_unlock_irqrestore(&desc->lock, flags);
+
+ unregister_handler_proc(irq, action);
+
+ /* Make sure it's not being used on another CPU: */
+ synchronize_irq(irq);
+
#ifdef CONFIG_DEBUG_SHIRQ
- dump_stack();
+ /*
+ * It's a shared IRQ -- the driver ought to be prepared for an IRQ
+ * event to happen even now it's being freed, so let's make sure that
+ * is so by doing an extra call to the handler ....
+ *
+ * ( We do this after actually deregistering it, to make sure that a
+ * 'real' IRQ doesn't run in * parallel with our fake. )
+ */
+ if (action->flags & IRQF_SHARED) {
+ local_irq_save(flags);
+ action->handler(irq, dev_id);
+ local_irq_restore(flags);
+ }
#endif
- spin_unlock_irqrestore(&desc->lock, flags);
- return;
+
+ if (action->thread) {
+ if (!test_bit(IRQTF_DIED, &action->thread_flags))
+ kthread_stop(action->thread);
+ put_task_struct(action->thread);
}
+
+ return action;
+}
+
+/**
+ * remove_irq - free an interrupt
+ * @irq: Interrupt line to free
+ * @act: irqaction for the interrupt
+ *
+ * Used to remove interrupts statically setup by the early boot process.
+ */
+void remove_irq(unsigned int irq, struct irqaction *act)
+{
+ __free_irq(irq, act->dev_id);
+}
+EXPORT_SYMBOL_GPL(remove_irq);
+
+/**
+ * free_irq - free an interrupt allocated with request_irq
+ * @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 = irq_to_desc(irq);
+
+ if (!desc)
+ return;
+
+ chip_bus_lock(irq, desc);
+ kfree(__free_irq(irq, dev_id));
+ chip_bus_sync_unlock(irq, desc);
}
EXPORT_SYMBOL(free_irq);
/**
- * request_irq - allocate an interrupt line
+ * request_threaded_irq - allocate an interrupt line
* @irq: Interrupt line to allocate
- * @handler: Function to be called when the IRQ occurs
+ * @handler: Function to be called when the IRQ occurs.
+ * Primary handler for threaded interrupts
+ * If NULL and thread_fn != NULL the default
+ * primary handler is installed
+ * @thread_fn: Function called from the irq handler thread
+ * If NULL, no irq thread is created
* @irqflags: Interrupt type flags
* @devname: An ascii name for the claiming device
* @dev_id: A cookie passed back to the handler function
* raises, you must take care both to initialise your hardware
* and to set up the interrupt handler in the right order.
*
+ * If you want to set up a threaded irq handler for your device
+ * then you need to supply @handler and @thread_fn. @handler ist
+ * still called in hard interrupt context and has to check
+ * whether the interrupt originates from the device. If yes it
+ * needs to disable the interrupt on the device and return
+ * IRQ_WAKE_THREAD which will wake up the handler thread and run
+ * @thread_fn. This split handler design is necessary to support
+ * shared interrupts.
+ *
* 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.
* Flags:
*
* IRQF_SHARED Interrupt is shared
- * IRQF_DISABLED Disable local interrupts while processing
* IRQF_SAMPLE_RANDOM The interrupt can be used for entropy
* IRQF_TRIGGER_* Specify active edge(s) or level
*
*/
-int request_irq(unsigned int irq, irq_handler_t handler,
- unsigned long irqflags, const char *devname, void *dev_id)
+int request_threaded_irq(unsigned int irq, irq_handler_t handler,
+ irq_handler_t thread_fn, unsigned long irqflags,
+ const char *devname, void *dev_id)
{
struct irqaction *action;
struct irq_desc *desc;
int retval;
-#ifdef CONFIG_LOCKDEP
- /*
- * Lockdep wants atomic interrupt handlers:
- */
- irqflags |= IRQF_DISABLED;
-#endif
/*
* Sanity-check: shared interrupts must pass in a real dev-ID,
* otherwise we'll have trouble later trying to figure out
if (desc->status & IRQ_NOREQUEST)
return -EINVAL;
- if (!handler)
- return -EINVAL;
- action = kmalloc(sizeof(struct irqaction), GFP_ATOMIC);
+ if (!handler) {
+ if (!thread_fn)
+ return -EINVAL;
+ handler = irq_default_primary_handler;
+ }
+
+ action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
if (!action)
return -ENOMEM;
action->handler = handler;
+ action->thread_fn = thread_fn;
action->flags = irqflags;
- cpus_clear(action->mask);
action->name = devname;
- action->next = NULL;
action->dev_id = dev_id;
+ chip_bus_lock(irq, desc);
retval = __setup_irq(irq, desc, action);
+ chip_bus_sync_unlock(irq, desc);
+
if (retval)
kfree(action);
#ifdef CONFIG_DEBUG_SHIRQ
- if (irqflags & IRQF_SHARED) {
+ if (!retval && (irqflags & IRQF_SHARED)) {
/*
* It's a shared IRQ -- the driver ought to be prepared for it
* to happen immediately, so let's make sure....
#endif
return retval;
}
-EXPORT_SYMBOL(request_irq);
+EXPORT_SYMBOL(request_threaded_irq);
+
+/**
+ * request_any_context_irq - allocate an interrupt line
+ * @irq: Interrupt line to allocate
+ * @handler: Function to be called when the IRQ occurs.
+ * Threaded handler for threaded interrupts.
+ * @flags: Interrupt type flags
+ * @name: 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. It selects either a
+ * hardirq or threaded handling method depending on the
+ * context.
+ *
+ * On failure, it returns a negative value. On success,
+ * it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
+ */
+int request_any_context_irq(unsigned int irq, irq_handler_t handler,
+ unsigned long flags, const char *name, void *dev_id)
+{
+ struct irq_desc *desc = irq_to_desc(irq);
+ int ret;
+
+ if (!desc)
+ return -EINVAL;
+
+ if (desc->status & IRQ_NESTED_THREAD) {
+ ret = request_threaded_irq(irq, NULL, handler,
+ flags, name, dev_id);
+ return !ret ? IRQC_IS_NESTED : ret;
+ }
+
+ ret = request_irq(irq, handler, flags, name, dev_id);
+ return !ret ? IRQC_IS_HARDIRQ : ret;
+}
+EXPORT_SYMBOL_GPL(request_any_context_irq);