Re: [PATCH 00/21] add and use devm_irq_of_parse_and_map()

From: Andreas Larsson
Date: Thu Jun 12 2014 - 06:04:31 EST


On 2014-06-04 13:13, nyushchenko@xxxxxxxxxxxxx wrote:
Currently many device tree aware drivers use irq_of_parse_and_map() to get
IRQ number and then devm_request_irq() to set up IRQ handler.

This causes a problem for exit path and for error paths: undo action for
irq_of_parse_and_map() is irq_dispose_mapping() that must not be called
while IRQ handler is defined, but devres moves free_irq() out of driver
so driver does not have safe place to call irq_dispose_mapping().

So many drivers do not call irq_dispose_mapping() at all, others call it
while IRQ handler is defined (which is incorrect and causes error messages
in logs), even others refuse to use devres for managing IRQ handlers.

This patchset adds devres version of irq_of_parse_and_map(), and updates
in-tree users of both devres and irq_of_parse_and_map() to use
devm_irq_of_parse_and_map() instead.


SPARC does not use OF_IRQ and has a different implementation of irq_of_parse_and_map than the one in drivers/of/irq.c. All code converted from irq_of_parse_and_map to devm_irq_of_parse_and_map in this patch set will be unlinkable for SPARC. This includes SPI in general and many drivers that are used for SPARC (of which several are currently only used on SPARC platforms).

Best regards,
Andreas Larsson
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/