irqdomain: Introduce irq_resolve_mapping()

Rework irq_find_mapping() to return an both an irq_desc pointer,
optionally the virtual irq number, and rename the result to
__irq_resolve_mapping(). a new helper called irq_resolve_mapping()
is provided for code that doesn't need the virtual irq number.

irq_find_mapping() is also rewritten in terms of __irq_resolve_mapping().

Signed-off-by: Marc Zyngier <maz@kernel.org>

1 files changed, 21 insertions, 2 deletions

diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index 2b696c9bcaaf..23e4ee523576 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -41,6 +41,7 @@ struct fwnode_handle;
 struct irq_domain;
 struct irq_chip;
 struct irq_data;
+struct irq_desc;
 struct cpumask;
 struct seq_file;
 struct irq_affinity_desc;
@@ -401,13 +402,31 @@ static inline unsigned int irq_create_mapping(struct irq_domain *host,
 	return irq_create_mapping_affinity(host, hwirq, NULL);
 }
 
+extern struct irq_desc *__irq_resolve_mapping(struct irq_domain *domain,
+					      irq_hw_number_t hwirq,
+					      unsigned int *irq);
+
+static inline struct irq_desc *irq_resolve_mapping(struct irq_domain *domain,
+						   irq_hw_number_t hwirq)
+{
+	return __irq_resolve_mapping(domain, hwirq, NULL);
+}
+
 /**
  * irq_find_mapping() - Find a linux irq from a hw irq number.
  * @domain: domain owning this hardware interrupt
  * @hwirq: hardware irq number in that domain space
  */
-extern unsigned int irq_find_mapping(struct irq_domain *host,
-				     irq_hw_number_t hwirq);
+static inline unsigned int irq_find_mapping(struct irq_domain *domain,
+					    irq_hw_number_t hwirq)
+{
+	unsigned int irq;
+
+	if (__irq_resolve_mapping(domain, hwirq, &irq))
+		return irq;
+
+	return 0;
+}
 
 static inline unsigned int irq_linear_revmap(struct irq_domain *domain,
 					     irq_hw_number_t hwirq)