dma: mv_xor: use request_irq() instead of devm_request_irq()
authorThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Thu, 22 Nov 2012 17:19:09 +0000 (18:19 +0100)
committerThomas Petazzoni <thomas.petazzoni@free-electrons.com>
Thu, 22 Nov 2012 17:19:09 +0000 (18:19 +0100)
commit2d0a074517da34a6386bdd9a22bc006c8fa21044
treee0353bf8c5cdf8edf41312ea4bc0a7623726dfae
parentc4b4b732b2e99e6e302d90d57f2a4f5c9516d9a3
dma: mv_xor: use request_irq() instead of devm_request_irq()

Even through the usage of devm_*() functions is generally recommended
over their classic variants, in the case of devm_request_irq()
combined with irq_of_parse_and_map(), it doesn't work nicely.

We have the following scenario:

 irq_of_parse_and_map(...)
 devm_request_irq(...)

For some reason, the driver initialization fails at a later
point. Since irq_of_parse_and_map() is no device-managed, we do a:

 irq_dispose_mapping(...)

Unfortunately, this doesn't work, because the free_irq() must be done
prior to calling irq_dispose_mapping(). But with the devm mechanism,
the automatic free_irq() would happen only after we get out of the
->probe() function.

So basically, we revert to using request_irq() with traditional error
handling, so that in case of error, free_irq() gets called before
irq_dispose_mapping().

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
drivers/dma/mv_xor.c