staging: wilc1000: fix compilation error for linux kernel 3.10

Added the missing API's required for interrupt property
for kernel 3.10.  These API' were available after 3.15 kernel
version so added these change to support compilation
on earlier version.

Signed-off-by: Ajay Singh <ajay.kathat@microchip.com>

Author: ajaykathat

drivers/staging/wilc1000/debugfs.h

@@ -8,6 +8,10 @@
 #define WILC_DEBUGFS_H
 
 #include <linux/kern_levels.h>
+#include <linux/version.h>
+#if KERNEL_VERSION(3, 15, 0) > LINUX_VERSION_CODE
+#include <linux/of_irq.h>
+#endif
 
 #define GENERIC_DBG		BIT(0)
 #define HOSTAPD_DBG		BIT(1)
@@ -47,4 +51,321 @@ extern atomic_t WILC_DEBUG_REGION;
 
 int wilc_debugfs_init(void);
 void wilc_debugfs_remove(void);
+
+#if KERNEL_VERSION(3, 15, 0) > LINUX_VERSION_CODE
+/**
+ * of_irq_parse_raw - Low level interrupt tree parsing
+ * @parent:	the device interrupt parent
+ * @addr:	address specifier (start of "reg" property of the device)
+ *              in be32 format
+ * @out_irq:	structure of_irq updated 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. It takes an interrupt specifier structure as
+ * input, walks the tree looking for any interrupt-map properties, translates
+ * the specifier for each map, and then returns the translated map.
+ */
+int of_irq_parse_raw(const __be32 *addr, struct of_phandle_args *out_irq)
+{
+	struct device_node *ipar, *tnode, *old = NULL, *newpar = NULL;
+	__be32 initial_match_array[MAX_PHANDLE_ARGS];
+	const __be32 *match_array = initial_match_array;
+	const __be32 *tmp, *imap, *imask;
+	const __be32 dummy_imask[] = { [0 ... MAX_PHANDLE_ARGS] = ~0 };
+	u32 intsize = 1, addrsize, newintsize = 0, newaddrsize = 0;
+	int imaplen, match, i;
+
+#ifdef DEBUG
+	of_print_phandle_args("of_irq_parse_raw: ", out_irq);
+#endif
+
+	ipar = of_node_get(out_irq->np);
+
+	/* 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_parse_raw: ipar=%s, size=%d\n",
+		 of_node_full_name(ipar), intsize);
+
+	if (out_irq->args_count != 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);
+
+	/* Range check so that the temporary buffer doesn't overflow */
+	if (WARN_ON(addrsize + intsize > MAX_PHANDLE_ARGS))
+		goto fail;
+
+	/* Precalculate the match array - this simplifies match loop */
+	for (i = 0; i < addrsize; i++)
+		initial_match_array[i] = addr ? addr[i] : 0;
+	for (i = 0; i < intsize; i++)
+		initial_match_array[addrsize + i] =
+			cpu_to_be32(out_irq->args[i]);
+
+	/* 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");
+			return 0;
+		}
+
+		/*
+		 * interrupt-map parsing does not work without a reg
+		 * property when #address-cells != 0
+		 */
+		if (addrsize && !addr) {
+			pr_debug(" -> no reg passed in when needed !\n");
+			goto fail;
+		}
+
+		/* 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 (!imask)
+			imask = dummy_imask;
+
+		/* Parse interrupt-map */
+		match = 0;
+		while (imaplen > (addrsize + intsize + 1) && !match) {
+			/* Compare specifiers */
+			match = 1;
+			for (i = 0; i < (addrsize + intsize); i++, imaplen--)
+				match &= !((match_array[i] ^ *imap++) &
+					   imask[i]);
+
+			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;
+			}
+
+			if (!of_device_is_available(newpar))
+				match = 0;
+
+			/* 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 (WARN_ON(newaddrsize + newintsize >
+				    MAX_PHANDLE_ARGS))
+				goto fail;
+			if (imaplen < (newaddrsize + newintsize))
+				goto fail;
+
+			imap += newaddrsize + newintsize;
+			imaplen -= newaddrsize + newintsize;
+
+			pr_debug(" -> imaplen=%d\n", imaplen);
+		}
+		if (!match)
+			goto fail;
+
+		/*
+		 * Successfully parsed an interrrupt-map translation; copy new
+		 * interrupt specifier into the out_irq structure
+		 */
+		out_irq->np = newpar;
+
+		match_array = imap - newaddrsize - newintsize;
+		for (i = 0; i < newintsize; i++)
+			out_irq->args[i] = be32_to_cpup(imap - newintsize + i);
+		out_irq->args_count = intsize = newintsize;
+		addrsize = newaddrsize;
+
+skiplevel:
+		/* Iterate again with new parent */
+		pr_debug(" -> new parent: %s\n", of_node_full_name(newpar));
+		of_node_put(ipar);
+		ipar = newpar;
+		newpar = NULL;
+	}
+ fail:
+	of_node_put(ipar);
+	of_node_put(newpar);
+
+	return -EINVAL;
+}
+
+static inline int of_irq_parse_oldworld(struct device_node *device, int index,
+				      struct of_phandle_args *out_irq)
+{
+	return -EINVAL;
+}
+/**
+ * of_irq_parse_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 for a node by walking the interrupt tree,
+ * finding which interrupt controller node it is attached to, and returning the
+ * interrupt specifier that can be used to retrieve a Linux IRQ number.
+ */
+int of_irq_parse_one(struct device_node *device, int index,
+		     struct of_phandle_args *out_irq)
+{
+	struct device_node *p;
+	const __be32 *intspec, *tmp, *addr;
+	u32 intsize, intlen;
+	int i, res;
+
+	pr_debug("of_irq_parse_one: dev=%s, index=%d\n",
+		 of_node_full_name(device), index);
+
+	/* OldWorld mac stuff is "special", handle out of line */
+	if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
+		return of_irq_parse_oldworld(device, index, out_irq);
+
+	/* Get the reg property (if any) */
+	addr = of_get_property(device, "reg", NULL);
+
+	/* Try the new-style interrupts-extended first */
+	res = of_parse_phandle_with_args(device, "interrupts-extended",
+					"#interrupt-cells", index, out_irq);
+	if (!res)
+		return of_irq_parse_raw(addr, 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);
+
+	/* 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) {
+		res = -EINVAL;
+		goto out;
+	}
+	intsize = be32_to_cpu(*tmp);
+
+	pr_debug(" intsize=%d intlen=%d\n", intsize, intlen);
+
+	/* Check index */
+	if ((index + 1) * intsize > intlen) {
+		res = -EINVAL;
+		goto out;
+	}
+
+	/* Copy intspec into irq structure */
+	intspec += index * intsize;
+	out_irq->np = p;
+	out_irq->args_count = intsize;
+	for (i = 0; i < intsize; i++)
+		out_irq->args[i] = be32_to_cpup(intspec++);
+
+	/* Check if there are any interrupt-map translations to process */
+	res = of_irq_parse_raw(addr, out_irq);
+ out:
+	of_node_put(p);
+	return res;
+}
+EXPORT_SYMBOL_GPL(of_irq_parse_one);
+
+/**
+ * of_irq_get - Decode a node's IRQ and return it as a Linux IRQ number
+ * @dev: pointer to device tree node
+ * @index: zero-based index of the IRQ
+ *
+ * Returns Linux IRQ number on success, or 0 on the IRQ mapping failure, or
+ * -EPROBE_DEFER if the IRQ domain is not yet created, or error code in case
+ * of any other failure.
+ */
+int of_irq_get(struct device_node *dev, int index)
+{
+	int rc;
+	struct of_phandle_args oirq;
+	struct irq_domain *domain;
+
+	rc = of_irq_parse_one(dev, index, &oirq);
+	if (rc)
+		return rc;
+
+	domain = irq_find_host(oirq.np);
+	if (!domain)
+		return -EPROBE_DEFER;
+
+	return irq_create_of_mapping(oirq.np, (const u32 *)&oirq.args,
+				     oirq.args_count);
+}
+#endif
 #endif /* WILC_DEBUGFS_H */