[PATCH 3/3] irq/irq_sim: implement irq_sim_irq2offset()

From: Bartosz Golaszewski
Date: Thu Oct 05 2017 - 08:45:18 EST


Add a routine allowing to retrieve the offset corresponding with an
allocated interrupt number from an irq_sim object.

Signed-off-by: Bartosz Golaszewski <brgl@xxxxxxxx>
---
include/linux/irq_sim.h | 1 +
kernel/irq/irq_sim.c | 15 +++++++++++++++
2 files changed, 16 insertions(+)

diff --git a/include/linux/irq_sim.h b/include/linux/irq_sim.h
index 246f593face8..e9768ca81e3e 100644
--- a/include/linux/irq_sim.h
+++ b/include/linux/irq_sim.h
@@ -41,5 +41,6 @@ void irq_sim_fini(struct irq_sim *sim);
void irq_sim_fire(struct irq_sim *sim, unsigned int offset);
int irq_sim_irqnum(struct irq_sim *sim, unsigned int offset);
int irq_sim_baseirq(struct irq_sim *sim);
+unsigned int irq_sim_irq2offset(struct irq_sim *sim, int irq);

#endif /* _LINUX_IRQ_SIM_H */
diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c
index 1be10d0e295f..9a9a1bc8853c 100644
--- a/kernel/irq/irq_sim.c
+++ b/kernel/irq/irq_sim.c
@@ -174,3 +174,18 @@ int irq_sim_baseirq(struct irq_sim *sim)
return irq_sim_irqnum(sim, 0);
}
EXPORT_SYMBOL_GPL(irq_sim_baseirq);
+
+/**
+ * irq_sim_irq2offset - Get the offset of an allocated interrupt.
+ *
+ * @sim: The interrupt simulator object.
+ * irq: Allocated interrupt number.
+ *
+ * Perform a reverse lookup for the interrupt number and return its offset in
+ * the array allocated by sim_irq.
+ */
+unsigned int irq_sim_irq2offset(struct irq_sim *sim, int irq)
+{
+ return irq - sim->irq_base;
+}
+EXPORT_SYMBOL_GPL(irq_sim_irq2offset);
--
2.13.2