Re: [PATCH 2/3] Input: twl6040-vibra: fix child-node lookup

H. Nikolaus Schaller
2017-11-13T14:39:48Z

Hi,

> Am 13.11.2017 um 15:19 schrieb Johan Hovold <johan@kernel.org>:
>
> On Mon, Nov 13, 2017 at 04:10:52PM +0200, Peter Ujfalusi wrote:
>
>> On 2017-11-11 17:43, Johan Hovold wrote:
>>> Fix child-node lookup during probe, which ended up searching the whole
>>> device tree depth-first starting at parent rather than just matching on
>>> its children.
>>>
>>> Later sanity checks on node properties (which would likely be missing)
>>> should prevent this from causing much trouble however, especially as the
>>> original premature free of the parent node has already been fixed
>>> separately (but that "fix" was apparently never backported to stable).
>>>
>>> Fixes: e7ec014a47e4 ("Input: twl6040-vibra - update for device tree support")
>>> Fixes: c52c545ead97 ("Input: twl6040-vibra - fix DT node memory management")
>>> Cc: stable <stable@vger.kernel.org> # 3.6
>>
>> Note that of_get_child_by_name() is not present in 3.6, this was the
>> reason the original implementation was using of_find_node_by_name()
>
> Ah, ok. So the lookup would have needed to be open-coded using
> for_each_child_of_node() back then, or if anyone wants to backport any
> of these fixes to before v3.7.

Just let me note that intensive DT support of OMAP4&5/ARM based boards didn't
start before ca. v3.13. So it is very unlikely that anyone is running a twl6040
based board with older kernels. It is different for twl4030/omap3 which was
used by several devices (N900, Pandora, GTA04) back in 2.6. So I don't
see a reason to backport this change to any kernel older than 3.16.

BR,
Nikolaus Schaller