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/* interrupt.h */
#ifndef _LINUX_INTERRUPT_H
#define _LINUX_INTERRUPT_H
#include <linux/kernel.h>
#include <asm/bitops.h>
struct irqaction {
void (*handler)(int, void *, struct pt_regs *);
unsigned long flags;
unsigned long mask;
const char *name;
void *dev_id;
struct irqaction *next;
};
extern unsigned long intr_count;
extern int bh_mask_count[32];
extern unsigned long bh_active;
extern unsigned long bh_mask;
extern void (*bh_base[32])(void);
asmlinkage void do_bottom_half(void);
/* Who gets which entry in bh_base. Things which will occur most often
should come first - in which case NET should be up the top with SERIAL/TQUEUE! */
enum {
TIMER_BH = 0,
CONSOLE_BH,
TQUEUE_BH,
DIGI_BH,
SERIAL_BH,
RISCOM8_BH,
NET_BH,
IMMEDIATE_BH,
KEYBOARD_BH,
CYCLADES_BH,
CM206_BH
};
extern inline void init_bh(int nr, void (*routine)(void))
{
bh_base[nr] = routine;
bh_mask_count[nr] = 0;
bh_mask |= 1 << nr;
}
extern inline void mark_bh(int nr)
{
set_bit(nr, &bh_active);
}
/*
* These use a mask count to correctly handle
* nested disable/enable calls
*/
extern inline void disable_bh(int nr)
{
bh_mask &= ~(1 << nr);
bh_mask_count[nr]++;
}
extern inline void enable_bh(int nr)
{
if (!--bh_mask_count[nr])
bh_mask |= 1 << nr;
}
/*
* start_bh_atomic/end_bh_atomic also nest
* naturally by using a counter
*/
extern inline void start_bh_atomic(void)
{
intr_count++;
barrier();
}
extern inline void end_bh_atomic(void)
{
barrier();
intr_count--;
}
/*
* Autoprobing for irqs:
*
* probe_irq_on() and probe_irq_off() provide robust primitives
* for accurate IRQ probing during kernel initialization. They are
* reasonably simple to use, are not "fooled" by spurious interrupts,
* and, unlike other attempts at IRQ probing, they do not get hung on
* stuck interrupts (such as unused PS2 mouse interfaces on ASUS boards).
*
* For reasonably foolproof probing, use them as follows:
*
* 1. clear and/or mask the device's internal interrupt.
* 2. sti();
* 3. irqs = probe_irq_on(); // "take over" all unassigned idle IRQs
* 4. enable the device and cause it to trigger an interrupt.
* 5. wait for the device to interrupt, using non-intrusive polling or a delay.
* 6. irq = probe_irq_off(irqs); // get IRQ number, 0=none, negative=multiple
* 7. service the device to clear its pending interrupt.
* 8. loop again if paranoia is required.
*
* probe_irq_on() returns a mask of allocated irq's.
*
* probe_irq_off() takes the mask as a parameter,
* and returns the irq number which occurred,
* or zero if none occurred, or a negative irq number
* if more than one irq occurred.
*/
extern unsigned long probe_irq_on(void); /* returns 0 on failure */
extern int probe_irq_off(unsigned long); /* returns 0 or negative on failure */
#endif
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