diff options
| -rw-r--r-- | Documentation/IRQ-domain.txt | 5 | ||||
| -rw-r--r-- | include/linux/irqdomain.h | 5 | ||||
| -rw-r--r-- | kernel/irq/irqdomain.c | 30 |
3 files changed, 40 insertions, 0 deletions
diff --git a/Documentation/IRQ-domain.txt b/Documentation/IRQ-domain.txt index 27dcaabfb4db..1401cece745a 100644 --- a/Documentation/IRQ-domain.txt +++ b/Documentation/IRQ-domain.txt @@ -93,6 +93,7 @@ Linux IRQ number into the hardware. Most drivers cannot use this mapping. ==== Legacy ==== +irq_domain_add_simple() irq_domain_add_legacy() irq_domain_add_legacy_isa() @@ -115,3 +116,7 @@ The legacy map should only be used if fixed IRQ mappings must be supported. For example, ISA controllers would use the legacy map for mapping Linux IRQs 0-15 so that existing ISA drivers get the correct IRQ numbers. + +Most users of legacy mappings should use irq_domain_add_simple() which +will use a legacy domain only if an IRQ range is supplied by the +system and will otherwise use a linear domain mapping. diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h index 5abb533eb8eb..17b60be30fff 100644 --- a/include/linux/irqdomain.h +++ b/include/linux/irqdomain.h @@ -112,6 +112,11 @@ struct irq_domain { }; #ifdef CONFIG_IRQ_DOMAIN +struct irq_domain *irq_domain_add_simple(struct device_node *of_node, + unsigned int size, + unsigned int first_irq, + const struct irq_domain_ops *ops, + void *host_data); struct irq_domain *irq_domain_add_legacy(struct device_node *of_node, unsigned int size, unsigned int first_irq, diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index d3968e91bfd2..0c51958c6335 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -140,6 +140,36 @@ static unsigned int irq_domain_legacy_revmap(struct irq_domain *domain, } /** + * irq_domain_add_simple() - Allocate and register a simple irq_domain. + * @of_node: pointer to interrupt controller's device tree node. + * @size: total number of irqs in mapping + * @first_irq: first number of irq block assigned to the domain + * @ops: map/unmap domain callbacks + * @host_data: Controller private data pointer + * + * Allocates a legacy irq_domain if irq_base is positive or a linear + * domain otherwise. + * + * This is intended to implement the expected behaviour for most + * interrupt controllers which is that a linear mapping should + * normally be used unless the system requires a legacy mapping in + * order to support supplying interrupt numbers during non-DT + * registration of devices. + */ +struct irq_domain *irq_domain_add_simple(struct device_node *of_node, + unsigned int size, + unsigned int first_irq, + const struct irq_domain_ops *ops, + void *host_data) +{ + if (first_irq > 0) + return irq_domain_add_legacy(of_node, size, first_irq, 0, + ops, host_data); + else + return irq_domain_add_linear(of_node, size, ops, host_data); +} + +/** * irq_domain_add_legacy() - Allocate and register a legacy revmap irq_domain. * @of_node: pointer to interrupt controller's device tree node. * @size: total number of irqs in legacy mapping |
