[PATCH 15/19] mfd: Don't convert just one IRQ using irqdomain if a range is provided

Lee Jones lee.jones at linaro.org
Fri Sep 7 08:46:12 EDT 2012


On Fri, Sep 07, 2012 at 12:35:41PM +0000, Arnd Bergmann wrote:
> On Friday 07 September 2012, Lee Jones wrote:
> > MFD core code attempts to convert specified hardware (local) IRQ
> > numbers to virtual-IRQs, which something Linux can understand. This
> > works great when only one IRQ is specified. However, converting
> > entire ranges is currently unsupported. If this occurs we issue a
> > kernel warning to inform the user of this, but we continue to
> > convert the first specified IRQ anyway and replace the range. This
> > is not the correct behaviour. This patch ensures that if a range
> > is specified, it is left untouched.
> > 
> > CC: Samuel Ortiz <sameo at linux.intel.com>
> > Signed-off-by: Lee Jones <lee.jones at linaro.org>
> 
> I don't see the advantage of the change. The warning already tells
> us that the input to mfd_add_device was incorrect, so nothing the
> function does can reliably fix it. Leaving the resource empty
> is just as wrong as listing only the first interrupt.

My thinking was to leave them in a range, then have the target driver
convert each entry in the range manually. But what you're saying is
that no registration should be attempted using ranges at all? What if
the range was vast? Surely a resource array a few hundred lines long
isn't correct either? My immediate example would be "GPIO_INT6", which
has 31 lines. Do you want them all splitting out individually?

-- 
Lee Jones
Linaro ST-Ericsson Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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