linux-imx

/*

 * Support for virtual IRQ subgroups.

 *

 * Copyright (C) 2010  Paul Mundt

 *

 * This file is subject to the terms and conditions of the GNU General Public

 * License.  See the file "COPYING" in the main directory of this archive

 * for more details.

 */

#define pr_fmt(fmt) "intc: " fmt

​

#include <linux/slab.h>

#include <linux/irq.h>

#include <linux/list.h>

#include <linux/radix-tree.h>

#include <linux/spinlock.h>

#include <linux/export.h>

#include "internals.h"

​

static struct intc_map_entry intc_irq_xlate[INTC_NR_IRQS];

​

struct intc_virq_list {

    unsigned int irq;

    struct intc_virq_list *next;

};

​

#define for_each_virq(entry, head) \

    for (entry = head; entry; entry = entry->next)

​

/*

 * Tags for the radix tree

 */

#define INTC_TAG_VIRQ_NEEDS_ALLOC   0

​

void intc_irq_xlate_set(unsigned int irq, intc_enum id, struct intc_desc_int *d)

{

    unsigned long flags;

​

    raw_spin_lock_irqsave(&intc_big_lock, flags);

    intc_irq_xlate[irq].enum_id = id;

    intc_irq_xlate[irq].desc = d;

    raw_spin_unlock_irqrestore(&intc_big_lock, flags);

}

​

struct intc_map_entry *intc_irq_xlate_get(unsigned int irq)

{

    return intc_irq_xlate + irq;

}

​

int intc_irq_lookup(const char *chipname, intc_enum enum_id)

{

    struct intc_map_entry *ptr;

    struct intc_desc_int *d;

    int irq = -1;

​

    list_for_each_entry(d, &intc_list, list) {

        int tagged;

​

        if (strcmp(d->chip.name, chipname) != 0)

            continue;

​

        /*

         * Catch early lookups for subgroup VIRQs that have not

         * yet been allocated an IRQ. This already includes a

         * fast-path out if the tree is untagged, so there is no

         * need to explicitly test the root tree.

         */

        tagged = radix_tree_tag_get(&d->tree, enum_id,

                        INTC_TAG_VIRQ_NEEDS_ALLOC);

        if (unlikely(tagged))

            break;

​

        ptr = radix_tree_lookup(&d->tree, enum_id);

        if (ptr) {

            irq = ptr - intc_irq_xlate;

            break;

        }

    }

​

    return irq;

}

EXPORT_SYMBOL_GPL(intc_irq_lookup);

​

static int add_virq_to_pirq(unsigned int irq, unsigned int virq)

{

    struct intc_virq_list *entry;

    struct intc_virq_list **last = NULL;

​

    /* scan for duplicates */

    for_each_virq(entry, irq_get_handler_data(irq)) {

        if (entry->irq == virq)

            return 0;