diff options
| author | Linus Walleij <linus.walleij@linaro.org> | 2013-06-06 12:10:23 +0100 |
|---|---|---|
| committer | Grant Likely <grant.likely@linaro.org> | 2013-06-08 21:15:09 +0100 |
| commit | 94a63da0ac1a67bfb8b30aec1086523c5031ea5a (patch) | |
| tree | c5931a9a34fc24267f494ee3e773e10dd3bd81ba | |
| parent | 275e31b10ce20613aedceaa5160129c64b260a98 (diff) | |
irqdomain: document the simple domain first_irq
The first_irq needs to be zero to get a linear domain and that
comes with special semantics. We want to simplify this going
forward but some documentation never hurts.
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@linaro.org>
| -rw-r--r-- | kernel/irq/irqdomain.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c index 8c4c8ea6a205..54a4d5223238 100644 --- a/kernel/irq/irqdomain.c +++ b/kernel/irq/irqdomain.c @@ -143,7 +143,10 @@ 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 + * @first_irq: first number of irq block assigned to the domain, + * pass zero to assign irqs on-the-fly. This will result in a + * linear IRQ domain so it is important to use irq_create_mapping() + * for each used IRQ, especially when SPARSE_IRQ is enabled. * @ops: map/unmap domain callbacks * @host_data: Controller private data pointer * |