irqdomain: Allow domain matching on irq_fwspec

When iterating over the irq domain list, we try to match a domain
either by calling a match() function or by comparing a number
of fields passed as parameters.

Both approaches are a bit restrictive:
- match() is DT specific and only takes a device node
- the fallback case only deals with the fwnode_handle

It would be useful if we had a per-domain function that would
actually perform the matching check on the whole of the
irq_fwspec structure. This would allow for a domain to triage
matching attempts that need to extend beyond the fwnode.

Let's introduce irq_find_matching_fwspec(), which takes a full
blown irq_fwspec structure, and call into a select() function
implemented by the irqdomain. irq_find_matching_fwnode() is
made a wrapper around irq_find_matching_fwspec in order to
preserve compatibility.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: devicetree@vger.kernel.org
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Rob Herring <robh+dt@kernel.org>
Link: http://lkml.kernel.org/r/1460365075-7316-2-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 files changed, 10 insertions, 9 deletions

diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index 3a519a01118b..503c5b9dd030 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -243,14 +243,15 @@ struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
 EXPORT_SYMBOL_GPL(irq_domain_add_legacy);
 
 /**
- * irq_find_matching_fwnode() - Locates a domain for a given fwnode
- * @fwnode: FW descriptor of the interrupt controller
+ * irq_find_matching_fwspec() - Locates a domain for a given fwspec
+ * @fwspec: FW specifier for an interrupt
  * @bus_token: domain-specific data
  */
-struct irq_domain *irq_find_matching_fwnode(struct fwnode_handle *fwnode,
+struct irq_domain *irq_find_matching_fwspec(struct irq_fwspec *fwspec,
 					    enum irq_domain_bus_token bus_token)
 {
 	struct irq_domain *h, *found = NULL;
+	struct fwnode_handle *fwnode = fwspec->fwnode;
 	int rc;
 
 	/* We might want to match the legacy controller last since
@@ -264,7 +265,9 @@ struct irq_domain *irq_find_matching_fwnode(struct fwnode_handle *fwnode,
 	 */
 	mutex_lock(&irq_domain_mutex);
 	list_for_each_entry(h, &irq_domain_list, link) {
-		if (h->ops->match)
+		if (h->ops->select && fwspec->param_count)
+			rc = h->ops->select(h, fwspec, bus_token);
+		else if (h->ops->match)
 			rc = h->ops->match(h, to_of_node(fwnode), bus_token);
 		else
 			rc = ((fwnode != NULL) && (h->fwnode == fwnode) &&
@@ -279,7 +282,7 @@ struct irq_domain *irq_find_matching_fwnode(struct fwnode_handle *fwnode,
 	mutex_unlock(&irq_domain_mutex);
 	return found;
 }
-EXPORT_SYMBOL_GPL(irq_find_matching_fwnode);
+EXPORT_SYMBOL_GPL(irq_find_matching_fwspec);
 
 /**
  * irq_set_default_host() - Set a "default" irq domain
@@ -574,11 +577,9 @@ unsigned int irq_create_fwspec_mapping(struct irq_fwspec *fwspec)
 	int virq;
 
 	if (fwspec->fwnode) {
-		domain = irq_find_matching_fwnode(fwspec->fwnode,
-						  DOMAIN_BUS_WIRED);
+		domain = irq_find_matching_fwspec(fwspec, DOMAIN_BUS_WIRED);
 		if (!domain)
-			domain = irq_find_matching_fwnode(fwspec->fwnode,
-							  DOMAIN_BUS_ANY);
+			domain = irq_find_matching_fwspec(fwspec, DOMAIN_BUS_ANY);
 	} else {
 		domain = irq_default_domain;
 	}