[PATCH v2 -next 1/2] irqdomain: Fix an issue where the Linux IRQ number is not stored

[Xu Qiang]

When using a NOMAP domain, __irq_resolve_mapping() doesn't store
the Linux IRQ number at the address optionally provided by the caller.
While this isn't a huge deal (the returned value is guaranteed
to the hwirq that was passed as a parameter), let's honour the letter
of the API by writing the expected value.

Fixes: d22558dd0a6c (“irqdomain: Introduce irq_resolve_mapping()”)
Signed-off-by: Xu Qiang <xuqiang36@xxxxxxxxxx>
---
 kernel/irq/irqdomain.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index d5ce96510549..481abb885d61 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -910,6 +910,8 @@ struct irq_desc *__irq_resolve_mapping(struct irq_domain *domain,
 			data = irq_domain_get_irq_data(domain, hwirq);
 			if (data && data->hwirq == hwirq)
 				desc = irq_data_to_desc(data);
+			if (irq && desc)
+				*irq = hwirq;
 		}
 
 		return desc;
-- 
2.17.1