1 files changed, 81 insertions, 0 deletions
diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
new file mode 100644
index 000000000000..8f2c10a784a4
--- /dev/null
+++ b/include/linux/irqdomain.h
@@ -0,0 +1,81 @@
+/*
+ * irq_domain - IRQ translation domains
+ *
+ * Translation infrastructure between hw and linux irq numbers.  This is
+ * helpful for interrupt controllers to implement mapping between hardware
+ * irq numbers and the Linux irq number space.
+ *
+ * irq_domains also have a hook for translating device tree interrupt
+ * representation into a hardware irq number that can be mapped back to a
+ * Linux irq number without any extra platform support code.
+ *
+ * irq_domain is expected to be embedded in an interrupt controller's private
+ * data structure.
+ */
+#ifndef _LINUX_IRQDOMAIN_H
+#define _LINUX_IRQDOMAIN_H
+
+#include <linux/irq.h>
+
+#ifdef CONFIG_IRQ_DOMAIN
+struct device_node;
+struct irq_domain;
+
+/**
+ * struct irq_domain_ops - Methods for irq_domain objects
+ * @to_irq: (optional) given a local hardware irq number, return the linux
+ *          irq number.  If to_irq is not implemented, then the irq_domain
+ *          will use this translation: irq = (domain->irq_base + hwirq)
+ * @dt_translate: Given a device tree node and interrupt specifier, decode
+ *                the hardware irq number and linux irq type value.
+ */
+struct irq_domain_ops {
+	unsigned int (*to_irq)(struct irq_domain *d, unsigned long hwirq);
+
+#ifdef CONFIG_OF
+	int (*dt_translate)(struct irq_domain *d, struct device_node *node,
+			    const u32 *intspec, unsigned int intsize,
+			    unsigned long *out_hwirq, unsigned int *out_type);
+#endif /* CONFIG_OF */
+};
+
+/**
+ * struct irq_domain - Hardware interrupt number translation object
+ * @list: Element in global irq_domain list.
+ * @irq_base: Start of irq_desc range assigned to the irq_domain.  The creator
+ *            of the irq_domain is responsible for allocating the array of
+ *            irq_desc structures.
+ * @nr_irq: Number of irqs managed by the irq domain
+ * @ops: pointer to irq_domain methods
+ * @priv: private data pointer for use by owner.  Not touched by irq_domain
+ *        core code.
+ * @of_node: (optional) Pointer to device tree nodes associated with the
+ *           irq_domain.  Used when decoding device tree interrupt specifiers.
+ */
+struct irq_domain {
+	struct list_head list;
+	unsigned int irq_base;
+	unsigned int nr_irq;
+	const struct irq_domain_ops *ops;
+	void *priv;
+	struct device_node *of_node;
+};
+
+/**
+ * irq_domain_to_irq() - Translate from a hardware irq to a linux irq number
+ *
+ * Returns the linux irq number associated with a hardware irq.  By default,
+ * the mapping is irq == domain->irq_base + hwirq, but this mapping can
+ * be overridden if the irq_domain implements a .to_irq() hook.
+ */
+static inline unsigned int irq_domain_to_irq(struct irq_domain *d,
+					     unsigned long hwirq)
+{
+	return d->ops->to_irq ? d->ops->to_irq(d, hwirq) : d->irq_base + hwirq;
+}
+
+extern void irq_domain_add(struct irq_domain *domain);
+extern void irq_domain_del(struct irq_domain *domain);
+#endif /* CONFIG_IRQ_DOMAIN */
+
+#endif /* _LINUX_IRQDOMAIN_H */