void free_irq(unsigned int irq, void *dev_id)
{
struct irqaction * action, **p;
unsigned long flags;
if (irq >= NR_IRQS) {
printk("Trying to free IRQ%d\n",irq);
return;
}
if (IS_RESERVED_IRQ(irq)) {
printk("Trying to free reserved IRQ %d\n", irq);
return;
}
for (p = irq + irq_action; (action = *p) != NULL; p = &action->next) {
if (action->dev_id != dev_id)
continue;
/* Found it - now free it */
save_flags(flags);
cli();
*p = action->next;
if (!irq[irq_action])
mask_irq(irq);
restore_flags(flags);
kfree(action);
return;
}
printk("Trying to free free IRQ%d\n",irq);
}
int request_irq(unsigned int irq,
void (*handler)(int, void *, struct pt_regs *),
unsigned long irqflags,
const char * devname,
void *dev_id)
{
int shared = 0;
struct irqaction * action, **p;
unsigned long flags;
if (irq >= NR_IRQS)
return -EINVAL;
if (IS_RESERVED_IRQ(irq))
return -EINVAL;
if (!handler)
return -EINVAL;
p = irq_action + irq;
action = *p;
if (action) {
/* Can't share interrupts unless both agree to */
if (!(action->flags & irqflags & SA_SHIRQ))
return -EBUSY;
/* Can't share interrupts unless both are same type */
if ((action->flags ^ irqflags) & SA_INTERRUPT)
return -EBUSY;
/* add new interrupt at end of irq queue */
do {
p = &action->next;
action = *p;
} while (action);
shared = 1;
}
action = (struct irqaction *)kmalloc(sizeof(struct irqaction),
GFP_KERNEL);
if (!action)
return -ENOMEM;
if (irqflags & SA_SAMPLE_RANDOM)
rand_initialize_irq(irq);
action->handler = handler;
action->flags = irqflags;
action->mask = 0;
action->name = devname;
action->next = NULL;
action->dev_id = dev_id;
save_flags(flags);
cli();
*p = action;
if (!shared)
unmask_irq(irq);
restore_flags(flags);
return 0;
}
/*
* Routine to check and install requested interrupt. Just sets up logical
* structures, doesn't alter interrupts at all.
*/
int uHALr_RequestInterrupt(unsigned int intNum,
PrHandler handler, const unsigned char *devname)
{
struct uHALis_IRQ *action;
if (intNum >= NR_IRQS)
return -1;
if (IS_RESERVED_IRQ(intNum))
return -1;
if (!handler)
return -1;
action = &uHALv_IRQVector[intNum];
/* Can't share interrupts (yet) */
if (action->handler)
return -1;
action->handler = handler;
action->name = devname;
action->flags = 0;
action->mask = 0;
action->next = 0;
return 0;
}
/* Call this routine before trying to change the routine attached to an IRQ */
int uHALr_FreeInterrupt(unsigned int intNum)
{
if (intNum >= NR_IRQS)
{
uHALr_printf("Can't free Interrupt %d\n", intNum);
return -1;
}
if (IS_RESERVED_IRQ(intNum))
{
uHALr_printf("Can't free reserved Interrupt %d\n", intNum);
return -1;
}
// Disable the interrupt & then remove the handler
uHALr_DisableInterrupt(intNum);
uHALv_IRQVector[intNum].handler = (PrHandler) 0;
#ifdef DEBUG
uHALr_printf("free'd Interrupt %d\n", intNum);
#endif
return 0;
}