tree 11794b64c41e8468db6d14243c5becce3b5b64c8
parent aed98048bd1c83469d96932c1901e867d9ba519a
author Mark Brown <broonie@opensource.wolfsonmicro.com> 1341487159 +0100
committer Grant Likely <grant.likely@secretlab.ca> 1342015157 +0100

irq_domain: Standardise legacy/linear domain selection

A large proportion of interrupt controllers that support legacy mappings
do so because non-DT systems need to use fixed IRQ numbers when registering
devices via buses but can otherwise use a linear mapping. The interrupt
controller itself typically is not affected by the mapping used and best
practice is to use a linear mapping where possible so drivers frequently
select at runtime depending on if a legacy range has been allocated to
them.

Standardise this behaviour by providing irq_domain_register_simple() which
will allocate a linear mapping unless a positive first_irq is provided in
which case it will fall back to a legacy mapping. This helps make best
practice for irq_domain adoption clearer.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>