drivers/of/irq.c - kernel/msm-4.9 - Gitiles

 /*
  *  Derived from arch/i386/kernel/irq.c
  *    Copyright (C) 1992 Linus Torvalds
  *  Adapted from arch/i386 by Gary Thomas
  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
  *  Updated and modified by Cort Dougan <cort@fsmlabs.com>
  *    Copyright (C) 1996-2001 Cort Dougan
  *  Adapted for Power Macintosh by Paul Mackerras
  *    Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * as published by the Free Software Foundation; either version
  * 2 of the License, or (at your option) any later version.
  *
  * This file contains the code used to make IRQ descriptions in the
  * device tree to actual irq numbers on an interrupt controller
  * driver.
  */

 #include <linux/errno.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_irq.h>
 #include <linux/string.h>

 /* For archs that don't support NO_IRQ (such as x86), provide a dummy value */
 #ifndef NO_IRQ
 #define NO_IRQ 0
 #endif

 /**
  * irq_of_parse_and_map - Parse and map an interrupt into linux virq space
  * @device: Device node of the device whose interrupt is to be mapped
  * @index: Index of the interrupt to map
  *
  * This function is a wrapper that chains of_irq_map_one() and
  * irq_create_of_mapping() to make things easier to callers
  */
 unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
 {
 	struct of_irq oirq;

 	if (of_irq_map_one(dev, index, &oirq))
 		return NO_IRQ;

 	return irq_create_of_mapping(oirq.controller, oirq.specifier,
 				     oirq.size);
 }
 EXPORT_SYMBOL_GPL(irq_of_parse_and_map);

 /**
  * of_irq_find_parent - Given a device node, find its interrupt parent node
  * @child: pointer to device node
  *
  * Returns a pointer to the interrupt parent node, or NULL if the interrupt
  * parent could not be determined.
  */
 struct device_node *of_irq_find_parent(struct device_node *child)
 {
 	struct device_node *p, *c = child;
 	const __be32 *parp;

 	if (!of_node_get(c))
 		return NULL;

 	do {
 		parp = of_get_property(c, "interrupt-parent", NULL);
 		if (parp == NULL)
 			p = of_get_parent(c);
 		else {
 			if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
 				p = of_node_get(of_irq_dflt_pic);
 			else
 				p = of_find_node_by_phandle(be32_to_cpup(parp));
 		}
 		of_node_put(c);
 		c = p;
 	} while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);

 	return (p == child) ? NULL : p;
 }

 /**
  * of_irq_map_raw - Low level interrupt tree parsing
  * @parent:	the device interrupt parent
  * @intspec:	interrupt specifier ("interrupts" property of the device)
  * @ointsize:   size of the passed in interrupt specifier
  * @addr:	address specifier (start of "reg" property of the device)
  * @out_irq:	structure of_irq filled by this function
  *
  * Returns 0 on success and a negative number on error
  *
  * This function is a low-level interrupt tree walking function. It
  * can be used to do a partial walk with synthetized reg and interrupts
  * properties, for example when resolving PCI interrupts when no device
  * node exist for the parent.
  */
 int of_irq_map_raw(struct device_node *parent, const __be32 *intspec,
 		   u32 ointsize, const __be32 *addr, struct of_irq *out_irq)
 {
 	struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL;
 	const __be32 *tmp, *imap, *imask;
 	u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
 	int imaplen, match, i;

 	pr_debug("of_irq_map_raw: par=%s,intspec=[0x%08x 0x%08x...],ointsize=%d\n",
 		 parent->full_name, be32_to_cpup(intspec),
 		 be32_to_cpup(intspec + 1), ointsize);

 	ipar = of_node_get(parent);

 	/* First get the #interrupt-cells property of the current cursor
 	 * that tells us how to interpret the passed-in intspec. If there
 	 * is none, we are nice and just walk up the tree
 	 */
 	do {
 		tmp = of_get_property(ipar, "#interrupt-cells", NULL);
 		if (tmp != NULL) {
 			intsize = be32_to_cpu(*tmp);
 			break;
 		}
 		tnode = ipar;
 		ipar = of_irq_find_parent(ipar);
 		of_node_put(tnode);
 	} while (ipar);
 	if (ipar == NULL) {
 		pr_debug(" -> no parent found !\n");
 		goto fail;
 	}

 	pr_debug("of_irq_map_raw: ipar=%s, size=%d\n", ipar->full_name, intsize);

 	if (ointsize != intsize)
 		return -EINVAL;

 	/* Look for this #address-cells. We have to implement the old linux
 	 * trick of looking for the parent here as some device-trees rely on it
 	 */
 	old = of_node_get(ipar);
 	do {
 		tmp = of_get_property(old, "#address-cells", NULL);
 		tnode = of_get_parent(old);
 		of_node_put(old);
 		old = tnode;
 	} while (old && tmp == NULL);
 	of_node_put(old);
 	old = NULL;
 	addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);

 	pr_debug(" -> addrsize=%d\n", addrsize);

 	/* Now start the actual "proper" walk of the interrupt tree */
 	while (ipar != NULL) {
 		/* Now check if cursor is an interrupt-controller and if it is
 		 * then we are done
 		 */
 		if (of_get_property(ipar, "interrupt-controller", NULL) !=
 				NULL) {
 			pr_debug(" -> got it !\n");
 			for (i = 0; i < intsize; i++)
 				out_irq->specifier[i] =
 						of_read_number(intspec +i, 1);
 			out_irq->size = intsize;
 			out_irq->controller = ipar;
 			of_node_put(old);
 			return 0;
 		}

 		/* Now look for an interrupt-map */
 		imap = of_get_property(ipar, "interrupt-map", &imaplen);
 		/* No interrupt map, check for an interrupt parent */
 		if (imap == NULL) {
 			pr_debug(" -> no map, getting parent\n");
 			newpar = of_irq_find_parent(ipar);
 			goto skiplevel;
 		}
 		imaplen /= sizeof(u32);

 		/* Look for a mask */
 		imask = of_get_property(ipar, "interrupt-map-mask", NULL);

 		/* If we were passed no "reg" property and we attempt to parse
 		 * an interrupt-map, then #address-cells must be 0.
 		 * Fail if it's not.
 		 */
 		if (addr == NULL && addrsize != 0) {
 			pr_debug(" -> no reg passed in when needed !\n");
 			goto fail;
 		}

 		/* Parse interrupt-map */
 		match = 0;
 		while (imaplen > (addrsize + intsize + 1) && !match) {
 			/* Compare specifiers */
 			match = 1;
 			for (i = 0; i < addrsize && match; ++i) {
 				u32 mask = imask ? imask[i] : 0xffffffffu;
 				match = ((addr[i] ^ imap[i]) & mask) == 0;
 			}
 			for (; i < (addrsize + intsize) && match; ++i) {
 				u32 mask = imask ? imask[i] : 0xffffffffu;
 				match =
 				   ((intspec[i-addrsize] ^ imap[i]) & mask) == 0;
 			}
 			imap += addrsize + intsize;
 			imaplen -= addrsize + intsize;

 			pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);

 			/* Get the interrupt parent */
 			if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
 				newpar = of_node_get(of_irq_dflt_pic);
 			else
 				newpar = of_find_node_by_phandle(be32_to_cpup(imap));
 			imap++;
 			--imaplen;

 			/* Check if not found */
 			if (newpar == NULL) {
 				pr_debug(" -> imap parent not found !\n");
 				goto fail;
 			}

 			/* Get #interrupt-cells and #address-cells of new
 			 * parent
 			 */
 			tmp = of_get_property(newpar, "#interrupt-cells", NULL);
 			if (tmp == NULL) {
 				pr_debug(" -> parent lacks #interrupt-cells!\n");
 				goto fail;
 			}
 			newintsize = be32_to_cpu(*tmp);
 			tmp = of_get_property(newpar, "#address-cells", NULL);
 			newaddrsize = (tmp == NULL) ? 0 : be32_to_cpu(*tmp);

 			pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
 			    newintsize, newaddrsize);

 			/* Check for malformed properties */
 			if (imaplen < (newaddrsize + newintsize))
 				goto fail;

 			imap += newaddrsize + newintsize;
 			imaplen -= newaddrsize + newintsize;

 			pr_debug(" -> imaplen=%d\n", imaplen);
 		}
 		if (!match)
 			goto fail;

 		of_node_put(old);
 		old = of_node_get(newpar);
 		addrsize = newaddrsize;
 		intsize = newintsize;
 		intspec = imap - intsize;
 		addr = intspec - addrsize;

 	skiplevel:
 		/* Iterate again with new parent */
 		pr_debug(" -> new parent: %s\n", newpar ? newpar->full_name : "<>");
 		of_node_put(ipar);
 		ipar = newpar;
 		newpar = NULL;
 	}
  fail:
 	of_node_put(ipar);
 	of_node_put(old);
 	of_node_put(newpar);

 	return -EINVAL;
 }
 EXPORT_SYMBOL_GPL(of_irq_map_raw);

 /**
  * of_irq_map_one - Resolve an interrupt for a device
  * @device: the device whose interrupt is to be resolved
  * @index: index of the interrupt to resolve
  * @out_irq: structure of_irq filled by this function
  *
  * This function resolves an interrupt, walking the tree, for a given
  * device-tree node. It's the high level pendant to of_irq_map_raw().
  */
 int of_irq_map_one(struct device_node *device, int index, struct of_irq *out_irq)
 {
 	struct device_node *p;
 	const __be32 *intspec, *tmp, *addr;
 	u32 intsize, intlen;
 	int res = -EINVAL;

 	pr_debug("of_irq_map_one: dev=%s, index=%d\n", device->full_name, index);

 	/* OldWorld mac stuff is "special", handle out of line */
 	if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
 		return of_irq_map_oldworld(device, index, out_irq);

 	/* Get the interrupts property */
 	intspec = of_get_property(device, "interrupts", &intlen);
 	if (intspec == NULL)
 		return -EINVAL;
 	intlen /= sizeof(*intspec);

 	pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);

 	/* Get the reg property (if any) */
 	addr = of_get_property(device, "reg", NULL);

 	/* Look for the interrupt parent. */
 	p = of_irq_find_parent(device);
 	if (p == NULL)
 		return -EINVAL;

 	/* Get size of interrupt specifier */
 	tmp = of_get_property(p, "#interrupt-cells", NULL);
 	if (tmp == NULL)
 		goto out;
 	intsize = be32_to_cpu(*tmp);

 	pr_debug(" intsize=%d intlen=%d\n", intsize, intlen);

 	/* Check index */
 	if ((index + 1) * intsize > intlen)
 		goto out;

 	/* Get new specifier and map it */
 	res = of_irq_map_raw(p, intspec + index * intsize, intsize,
 			     addr, out_irq);
  out:
 	of_node_put(p);
 	return res;
 }
 EXPORT_SYMBOL_GPL(of_irq_map_one);

 /**
  * of_irq_to_resource - Decode a node's IRQ and return it as a resource
  * @dev: pointer to device tree node
  * @index: zero-based index of the irq
  * @r: pointer to resource structure to return result into.
  */
 int of_irq_to_resource(struct device_node *dev, int index, struct resource *r)
 {
 	int irq = irq_of_parse_and_map(dev, index);

 	/* Only dereference the resource if both the
 	 * resource and the irq are valid. */
 	if (r && irq != NO_IRQ) {
 		r->start = r->end = irq;
 		r->flags = IORESOURCE_IRQ;
 		r->name = dev->full_name;
 	}

 	return irq;
 }
 EXPORT_SYMBOL_GPL(of_irq_to_resource);

 /**
  * of_irq_count - Count the number of IRQs a node uses
  * @dev: pointer to device tree node
  */
 int of_irq_count(struct device_node *dev)
 {
 	int nr = 0;

 	while (of_irq_to_resource(dev, nr, NULL) != NO_IRQ)
 		nr++;

 	return nr;
 }

 /**
  * of_irq_to_resource_table - Fill in resource table with node's IRQ info
  * @dev: pointer to device tree node
  * @res: array of resources to fill in
  * @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
  *
  * Returns the size of the filled in table (up to @nr_irqs).
  */
 int of_irq_to_resource_table(struct device_node *dev, struct resource *res,
 		int nr_irqs)
 {
 	int i;

 	for (i = 0; i < nr_irqs; i++, res++)
 		if (of_irq_to_resource(dev, i, res) == NO_IRQ)
 			break;

 	return i;
 }
	/*
	* Derived from arch/i386/kernel/irq.c
	* Copyright (C) 1992 Linus Torvalds
	* Adapted from arch/i386 by Gary Thomas
	* Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
	* Updated and modified by Cort Dougan <cort@fsmlabs.com>
	* Copyright (C) 1996-2001 Cort Dougan
	* Adapted for Power Macintosh by Paul Mackerras
	* Copyright (C) 1996 Paul Mackerras (paulus@cs.anu.edu.au)
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* as published by the Free Software Foundation; either version
	* 2 of the License, or (at your option) any later version.
	*
	* This file contains the code used to make IRQ descriptions in the
	* device tree to actual irq numbers on an interrupt controller
	* driver.
	*/

	#include <linux/errno.h>
	#include <linux/module.h>
	#include <linux/of.h>
	#include <linux/of_irq.h>
	#include <linux/string.h>

	/* For archs that don't support NO_IRQ (such as x86), provide a dummy value */
	#ifndef NO_IRQ
	#define NO_IRQ 0
	#endif

	/**
	* irq_of_parse_and_map - Parse and map an interrupt into linux virq space
	* @device: Device node of the device whose interrupt is to be mapped
	* @index: Index of the interrupt to map
	*
	* This function is a wrapper that chains of_irq_map_one() and
	* irq_create_of_mapping() to make things easier to callers
	*/
	unsigned int irq_of_parse_and_map(struct device_node *dev, int index)
	{
	struct of_irq oirq;

	if (of_irq_map_one(dev, index, &oirq))
	return NO_IRQ;

	return irq_create_of_mapping(oirq.controller, oirq.specifier,
	oirq.size);
	}
	EXPORT_SYMBOL_GPL(irq_of_parse_and_map);

	/**
	* of_irq_find_parent - Given a device node, find its interrupt parent node
	* @child: pointer to device node
	*
	* Returns a pointer to the interrupt parent node, or NULL if the interrupt
	* parent could not be determined.
	*/
	struct device_node of_irq_find_parent(struct device_node child)
	{
	struct device_node p, c = child;
	const __be32 *parp;

	if (!of_node_get(c))
	return NULL;

	do {
	parp = of_get_property(c, "interrupt-parent", NULL);
	if (parp == NULL)
	p = of_get_parent(c);
	else {
	if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
	p = of_node_get(of_irq_dflt_pic);
	else
	p = of_find_node_by_phandle(be32_to_cpup(parp));
	}
	of_node_put(c);
	c = p;
	} while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);

	return (p == child) ? NULL : p;
	}

	/**
	* of_irq_map_raw - Low level interrupt tree parsing
	* @parent: the device interrupt parent
	* @intspec: interrupt specifier ("interrupts" property of the device)
	* @ointsize: size of the passed in interrupt specifier
	* @addr: address specifier (start of "reg" property of the device)
	* @out_irq: structure of_irq filled by this function
	*
	* Returns 0 on success and a negative number on error
	*
	* This function is a low-level interrupt tree walking function. It
	* can be used to do a partial walk with synthetized reg and interrupts
	* properties, for example when resolving PCI interrupts when no device
	* node exist for the parent.
	*/
	int of_irq_map_raw(struct device_node parent, const __be32 intspec,
	u32 ointsize, const __be32 addr, struct of_irq out_irq)
	{
	struct device_node ipar, tnode, old = NULL, newpar = NULL;
	const __be32 tmp, imap, *imask;
	u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
	int imaplen, match, i;

	pr_debug("of_irq_map_raw: par=%s,intspec=[0x%08x 0x%08x...],ointsize=%d\n",
	parent->full_name, be32_to_cpup(intspec),
	be32_to_cpup(intspec + 1), ointsize);

	ipar = of_node_get(parent);

	/* First get the #interrupt-cells property of the current cursor
	* that tells us how to interpret the passed-in intspec. If there
	* is none, we are nice and just walk up the tree
	*/
	do {
	tmp = of_get_property(ipar, "#interrupt-cells", NULL);
	if (tmp != NULL) {
	intsize = be32_to_cpu(*tmp);
	break;
	}
	tnode = ipar;
	ipar = of_irq_find_parent(ipar);
	of_node_put(tnode);
	} while (ipar);
	if (ipar == NULL) {
	pr_debug(" -> no parent found !\n");
	goto fail;
	}

	pr_debug("of_irq_map_raw: ipar=%s, size=%d\n", ipar->full_name, intsize);

	if (ointsize != intsize)
	return -EINVAL;

	/* Look for this #address-cells. We have to implement the old linux
	* trick of looking for the parent here as some device-trees rely on it
	*/
	old = of_node_get(ipar);
	do {
	tmp = of_get_property(old, "#address-cells", NULL);
	tnode = of_get_parent(old);
	of_node_put(old);
	old = tnode;
	} while (old && tmp == NULL);
	of_node_put(old);
	old = NULL;
	addrsize = (tmp == NULL) ? 2 : be32_to_cpu(*tmp);

	pr_debug(" -> addrsize=%d\n", addrsize);

	/* Now start the actual "proper" walk of the interrupt tree */
	while (ipar != NULL) {
	/* Now check if cursor is an interrupt-controller and if it is
	* then we are done
	*/
	if (of_get_property(ipar, "interrupt-controller", NULL) !=
	NULL) {
	pr_debug(" -> got it !\n");
	for (i = 0; i < intsize; i++)
	out_irq->specifier[i] =
	of_read_number(intspec +i, 1);
	out_irq->size = intsize;
	out_irq->controller = ipar;
	of_node_put(old);
	return 0;
	}

	/* Now look for an interrupt-map */
	imap = of_get_property(ipar, "interrupt-map", &imaplen);
	/* No interrupt map, check for an interrupt parent */
	if (imap == NULL) {
	pr_debug(" -> no map, getting parent\n");
	newpar = of_irq_find_parent(ipar);
	goto skiplevel;
	}
	imaplen /= sizeof(u32);

	/* Look for a mask */
	imask = of_get_property(ipar, "interrupt-map-mask", NULL);

	/* If we were passed no "reg" property and we attempt to parse
	* an interrupt-map, then #address-cells must be 0.
	* Fail if it's not.
	*/
	if (addr == NULL && addrsize != 0) {
	pr_debug(" -> no reg passed in when needed !\n");
	goto fail;
	}

	/* Parse interrupt-map */
	match = 0;
	while (imaplen > (addrsize + intsize + 1) && !match) {
	/* Compare specifiers */
	match = 1;
	for (i = 0; i < addrsize && match; ++i) {
	u32 mask = imask ? imask[i] : 0xffffffffu;
	match = ((addr[i] ^ imap[i]) & mask) == 0;
	}
	for (; i < (addrsize + intsize) && match; ++i) {
	u32 mask = imask ? imask[i] : 0xffffffffu;
	match =
	((intspec[i-addrsize] ^ imap[i]) & mask) == 0;
	}
	imap += addrsize + intsize;
	imaplen -= addrsize + intsize;

	pr_debug(" -> match=%d (imaplen=%d)\n", match, imaplen);

	/* Get the interrupt parent */
	if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
	newpar = of_node_get(of_irq_dflt_pic);
	else
	newpar = of_find_node_by_phandle(be32_to_cpup(imap));
	imap++;
	--imaplen;

	/* Check if not found */
	if (newpar == NULL) {
	pr_debug(" -> imap parent not found !\n");
	goto fail;
	}

	/* Get #interrupt-cells and #address-cells of new
	* parent
	*/
	tmp = of_get_property(newpar, "#interrupt-cells", NULL);
	if (tmp == NULL) {
	pr_debug(" -> parent lacks #interrupt-cells!\n");
	goto fail;
	}
	newintsize = be32_to_cpu(*tmp);
	tmp = of_get_property(newpar, "#address-cells", NULL);
	newaddrsize = (tmp == NULL) ? 0 : be32_to_cpu(*tmp);

	pr_debug(" -> newintsize=%d, newaddrsize=%d\n",
	newintsize, newaddrsize);

	/* Check for malformed properties */
	if (imaplen < (newaddrsize + newintsize))
	goto fail;

	imap += newaddrsize + newintsize;
	imaplen -= newaddrsize + newintsize;

	pr_debug(" -> imaplen=%d\n", imaplen);
	}
	if (!match)
	goto fail;

	of_node_put(old);
	old = of_node_get(newpar);
	addrsize = newaddrsize;
	intsize = newintsize;
	intspec = imap - intsize;
	addr = intspec - addrsize;

	skiplevel:
	/* Iterate again with new parent */
	pr_debug(" -> new parent: %s\n", newpar ? newpar->full_name : "<>");
	of_node_put(ipar);
	ipar = newpar;
	newpar = NULL;
	}
	fail:
	of_node_put(ipar);
	of_node_put(old);
	of_node_put(newpar);

	return -EINVAL;
	}
	EXPORT_SYMBOL_GPL(of_irq_map_raw);

	/**
	* of_irq_map_one - Resolve an interrupt for a device
	* @device: the device whose interrupt is to be resolved
	* @index: index of the interrupt to resolve
	* @out_irq: structure of_irq filled by this function
	*
	* This function resolves an interrupt, walking the tree, for a given
	* device-tree node. It's the high level pendant to of_irq_map_raw().
	*/
	int of_irq_map_one(struct device_node device, int index, struct of_irq out_irq)
	{
	struct device_node *p;
	const __be32 intspec, tmp, *addr;
	u32 intsize, intlen;
	int res = -EINVAL;

	pr_debug("of_irq_map_one: dev=%s, index=%d\n", device->full_name, index);

	/* OldWorld mac stuff is "special", handle out of line */
	if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
	return of_irq_map_oldworld(device, index, out_irq);

	/* Get the interrupts property */
	intspec = of_get_property(device, "interrupts", &intlen);
	if (intspec == NULL)
	return -EINVAL;
	intlen /= sizeof(*intspec);

	pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);

	/* Get the reg property (if any) */
	addr = of_get_property(device, "reg", NULL);

	/* Look for the interrupt parent. */
	p = of_irq_find_parent(device);
	if (p == NULL)
	return -EINVAL;

	/* Get size of interrupt specifier */
	tmp = of_get_property(p, "#interrupt-cells", NULL);
	if (tmp == NULL)
	goto out;
	intsize = be32_to_cpu(*tmp);

	pr_debug(" intsize=%d intlen=%d\n", intsize, intlen);

	/* Check index */
	if ((index + 1) * intsize > intlen)
	goto out;

	/* Get new specifier and map it */
	res = of_irq_map_raw(p, intspec + index * intsize, intsize,
	addr, out_irq);
	out:
	of_node_put(p);
	return res;
	}
	EXPORT_SYMBOL_GPL(of_irq_map_one);

	/**
	* of_irq_to_resource - Decode a node's IRQ and return it as a resource
	* @dev: pointer to device tree node
	* @index: zero-based index of the irq
	* @r: pointer to resource structure to return result into.
	*/
	int of_irq_to_resource(struct device_node dev, int index, struct resource r)
	{
	int irq = irq_of_parse_and_map(dev, index);

	/* Only dereference the resource if both the
	* resource and the irq are valid. */
	if (r && irq != NO_IRQ) {
	r->start = r->end = irq;
	r->flags = IORESOURCE_IRQ;
	r->name = dev->full_name;
	}

	return irq;
	}
	EXPORT_SYMBOL_GPL(of_irq_to_resource);

	/**
	* of_irq_count - Count the number of IRQs a node uses
	* @dev: pointer to device tree node
	*/
	int of_irq_count(struct device_node *dev)
	{
	int nr = 0;

	while (of_irq_to_resource(dev, nr, NULL) != NO_IRQ)
	nr++;

	return nr;
	}

	/**
	* of_irq_to_resource_table - Fill in resource table with node's IRQ info
	* @dev: pointer to device tree node
	* @res: array of resources to fill in
	* @nr_irqs: the number of IRQs (and upper bound for num of @res elements)
	*
	* Returns the size of the filled in table (up to @nr_irqs).
	*/
	int of_irq_to_resource_table(struct device_node dev, struct resource res,
	int nr_irqs)
	{
	int i;

	for (i = 0; i < nr_irqs; i++, res++)
	if (of_irq_to_resource(dev, i, res) == NO_IRQ)
	break;

	return i;
	}