On Tue, 15 May 2012 17:29:14 +0900, Kukjin Kim <kgene.kim@xxxxxxxxxxx> wrote:
> Thomas Abraham wrote:
> >
> > The interrupt parent lookup fails for a node that is a interrupt-controller
> > but does not have an explict interrupt-parent property and instead inherits
> > this property from the root node.
> >
> > Consider the nodes listed below.
> >
> > / {
> > interrupt-parent = <&intc_level1>;
> >
> > intc_level1: interrupt-controller@xxx {
> > interrupt-controller;
> > #interrupt-cells = <3>;
> > <rest of the properties here>;
> > };
> >
> > intc_level2: interrupt-controller@yyy {
> > interrupt-controller;
> > #interrupt-cells = <2>;
> > <rest of the properties here>;
> > };
> > };
> >
> > The interrupt parent lookup for interrupt-controller@yyy fails. It inherits
> > the interrupt-parent property from the root node and the root node ('/')
> > specifies a 'interrupt-parent' property which represents the default interrupt
> > root controller. But, the property '#interrupt-cells' might not be specified
> > in the root node.
> >
> > In case a interrupt controller node does not include a 'interrupt-parent'
> > property but inherits that property from the root node, the check for
> > 'interrupt-cells' property in the root node fails. Fix this removing the
> > check for 'interrupt-cells' property.
Hmmm... I dont see the bug... From your description above, I see the
following sequence.
First iteration:
child = &ic@yyy;
cannot find "interrupt-parent" so take 'if' clause
p = of_get_parent(child); (root)
iteration continues because #interrupt-cells not found in 'p'(root)
Second iteration:
child = root;
found "interrupt-parent", so take 'else' clause
p = of_find_node_by_phandle(); (ic@xxx)
iteration stops because #interrupt-cells is found in 'p'(ic@xxx)
What am I missing in my admittedly short look at the code?
g.
> >
> > Signed-off-by: Thomas Abraham <thomas.abraham@xxxxxxxxxx>
> > ---
> > drivers/of/irq.c | 4 +++-
> > 1 files changed, 3 insertions(+), 1 deletions(-)
> >
> > diff --git a/drivers/of/irq.c b/drivers/of/irq.c
> > index 9cf0060..a520363 100644
> > --- a/drivers/of/irq.c
> > +++ b/drivers/of/irq.c
> > @@ -66,14 +66,16 @@ struct device_node *of_irq_find_parent(struct device_node *child)
> > if (parp == NULL)
> > p = of_get_parent(child);
> > else {
> > + of_node_put(child);
> > if (of_irq_workarounds & OF_IMAP_NO_PHANDLE)
> > p = of_node_get(of_irq_dflt_pic);
> > else
> > p = of_find_node_by_phandle(be32_to_cpup(parp));
> > + return p;
> > }
> > of_node_put(child);
> > child = p;
> > - } while (p && of_get_property(p, "#interrupt-cells", NULL) == NULL);
> > + } while (p);
This does break one use-case. Sometimes the interrupt-parent is the
same node when an
> >
> > return p;
> > }
> > --
> > 1.7.5.4
>
> Hi Grant and Rob,
>
> I'm ok on this and this patch and #11 patch in this series are required for patches that add device tree based support for wakeup
> interrupts on EXYNOS5250.
>
> So could you have a look at this patch and let us know if this is okay or any rework is required.
>
> Thanks.
>
> Best regards,
> Kgene.
> --
> Kukjin Kim <kgene.kim@xxxxxxxxxxx>, Senior Engineer,
> SW Solution Development Team, Samsung Electronics Co., Ltd.
>
--
Grant Likely, B.Sc, P.Eng.
Secret Lab Technologies, Ltd.
--
To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
