diff options
Diffstat (limited to 'arch/arm/kernel/irq.c')
| -rw-r--r-- | arch/arm/kernel/irq.c | 122 |
1 files changed, 78 insertions, 44 deletions
diff --git a/arch/arm/kernel/irq.c b/arch/arm/kernel/irq.c index ae599d2558cf..75ba611b1f92 100644 --- a/arch/arm/kernel/irq.c +++ b/arch/arm/kernel/irq.c @@ -2,7 +2,7 @@ * linux/arch/arm/kernel/irq.c * * Copyright (C) 1992 Linus Torvalds - * Modifications for ARM processor Copyright (C) 1995-1998 Russell King. + * Modifications for ARM processor Copyright (C) 1995-2000 Russell King. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as @@ -29,9 +29,11 @@ #include <linux/smp.h> #include <linux/init.h> -#include <asm/hardware.h> -#include <asm/io.h> +#include <asm/irq.h> #include <asm/system.h> +#include <asm/mach/irq.h> + +#include <asm/arch/irq.h> /* pick up fixup_irq definition */ /* * Maximum IRQ count. Currently, this is arbitary. However, it should @@ -42,41 +44,11 @@ */ #define MAX_IRQ_CNT 100000 -spinlock_t irq_controller_lock; - -int setup_arm_irq(int, struct irqaction *); -extern int get_fiq_list(char *); -extern void init_FIQ(void); - -struct irqdesc { - unsigned int nomask : 1; /* IRQ does not mask in IRQ */ - unsigned int enabled : 1; /* IRQ is currently enabled */ - unsigned int triggered: 1; /* IRQ has occurred */ - unsigned int probing : 1; /* IRQ in use for a probe */ - unsigned int probe_ok : 1; /* IRQ can be used for probe */ - unsigned int valid : 1; /* IRQ claimable */ - unsigned int noautoenable : 1; /* don't automatically enable IRQ */ - unsigned int unused :25; - void (*mask_ack)(unsigned int irq); /* Mask and acknowledge IRQ */ - void (*mask)(unsigned int irq); /* Mask IRQ */ - void (*unmask)(unsigned int irq); /* Unmask IRQ */ - struct irqaction *action; - /* - * IRQ lock detection - */ - unsigned int lck_cnt; - unsigned int lck_pc; - unsigned int lck_jif; -}; - -static struct irqdesc irq_desc[NR_IRQS]; static volatile unsigned long irq_err_count; +static spinlock_t irq_controller_lock; -/* - * Get architecture specific interrupt handlers - * and interrupt initialisation. - */ -#include <asm/arch/irq.h> +struct irqdesc irq_desc[NR_IRQS]; +void (*init_arch_irq)(void) __initdata = NULL; /* * Dummy mask/unmask handler @@ -85,6 +57,14 @@ static void dummy_mask_unmask_irq(unsigned int irq) { } +/** + * disable_irq - disable an irq and wait for completion + * @irq: Interrupt to disable + * + * Disable the selected interrupt line. + * + * This function may be called - with care - from IRQ context. + */ void disable_irq(unsigned int irq) { unsigned long flags; @@ -95,6 +75,14 @@ void disable_irq(unsigned int irq) spin_unlock_irqrestore(&irq_controller_lock, flags); } +/** + * enable_irq - enable interrupt handling on an irq + * @irq: Interrupt to enable + * + * Re-enables the processing of interrupts on this IRQ line + * + * This function may be called from IRQ context. + */ void enable_irq(unsigned int irq) { unsigned long flags; @@ -271,6 +259,7 @@ int setup_arm_irq(int irq, struct irqaction * new) int shared = 0; struct irqaction *old, **p; unsigned long flags; + struct irqdesc *desc; /* * Some drivers like serial.c use request_irq() heavily, @@ -292,8 +281,9 @@ int setup_arm_irq(int irq, struct irqaction * new) /* * The following block of code has to be executed atomically */ + desc = irq_desc + irq; spin_lock_irqsave(&irq_controller_lock, flags); - p = &irq_desc[irq].action; + p = &desc->action; if ((old = *p) != NULL) { /* Can't share interrupts unless both agree to */ if (!(old->flags & new->flags & SA_SHIRQ)) { @@ -312,11 +302,11 @@ int setup_arm_irq(int irq, struct irqaction * new) *p = new; if (!shared) { - irq_desc[irq].nomask = (new->flags & SA_IRQNOMASK) ? 1 : 0; - irq_desc[irq].probing = 0; - if (!irq_desc[irq].noautoenable) { - irq_desc[irq].enabled = 1; - irq_desc[irq].unmask(irq); + desc->nomask = (new->flags & SA_IRQNOMASK) ? 1 : 0; + desc->probing = 0; + if (!desc->noautoenable) { + desc->enabled = 1; + desc->unmask(irq); } } @@ -324,13 +314,45 @@ int setup_arm_irq(int irq, struct irqaction * new) return 0; } +/** + * 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, void (*handler)(int, void *, struct pt_regs *), unsigned long irq_flags, const char * devname, void *dev_id) { unsigned long retval; struct irqaction *action; - if (irq >= NR_IRQS || !irq_desc[irq].valid || !handler) + if (irq >= NR_IRQS || !irq_desc[irq].valid || !handler || + (irq_flags & SA_SHIRQ && !dev_id)) return -EINVAL; action = (struct irqaction *)kmalloc(sizeof(struct irqaction), GFP_KERNEL); @@ -351,6 +373,18 @@ int request_irq(unsigned int irq, void (*handler)(int, void *, struct pt_regs *) return retval; } +/** + * 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. + * + * This function may be called from interrupt context. + */ void free_irq(unsigned int irq, void *dev_id) { struct irqaction * action, **p; @@ -486,6 +520,6 @@ void __init init_IRQ(void) irq_desc[irq].unmask = dummy_mask_unmask_irq; } - irq_init_irq(); + init_arch_irq(); init_dma(); } |