Re: [PATCH 5/8] of/overlay: Introduce DT overlay support

From: Grant Likely
Date: Wed Nov 26 2014 - 10:18:47 EST


On Wed, Nov 26, 2014 at 1:11 PM, Paul Bolle <pebolle@xxxxxxxxxx> wrote:
> On Fri, 2014-11-21 at 01:35 +0000, Grant Likely wrote:
>> From: Pantelis Antoniou <pantelis.antoniou@xxxxxxxxxxxx>
>>
>> Overlays are a method to dynamically modify part of the kernel's
>> device tree with dynamically loaded data. Add the core functionality to
>> parse, apply and remove an overlay changeset. The core functionality
>> takes care of managing the overlay data format and performing the add
>> and remove. Drivers are expected to use the overlay functionality to
>> support custom expansion busses commonly found on consumer development
>> boards like the BeagleBone or Raspberry Pi.
>>
>> The overlay code uses CONFIG_OF_DYNAMIC changesets to perform the low
>> level work of modifying the devicetree.
>>
>> Documentation about internal and APIs is provided in
>> Documentation/devicetree/overlay-notes.txt
>>
>> v2:
>> - Switch from __of_node_alloc() to __of_node_dup()
>> - Documentation fixups
>> - Remove 2-pass processing of properties
>> - Remove separate ov_lock; just use the DT mutex.
>> v1:
>> - Drop delete capability using '-' prefix. The '-' prefixed names
>> are valid properties and nodes and there is no need for it just yet.
>> - Do not update special properties - name & phandle ones.
>> - Change order of node attachment, so that the special property update
>> works.
>>
>> Signed-off-by: Pantelis Antoniou <pantelis.antoniou@xxxxxxxxxxxx>
>> Signed-off-by: Grant Likely <grant.likely@xxxxxxxxxx>
>
> Now commit 7518b5890d8a ("of/overlay: Introduce DT overlay support"),
> included in today's linux-next (next-20141126).

Yes, I pushed it out yesterday. Beyond merely stating a fact, I don't
understand what you're trying to point out here. Is this commit
causing a problem?

>>[...]
>> diff --git a/drivers/of/Kconfig b/drivers/of/Kconfig
>> index fbe8f8d418f7..18b2e2539f84 100644
>> --- a/drivers/of/Kconfig
>> +++ b/drivers/of/Kconfig
>> @@ -84,4 +84,11 @@ config OF_RESERVED_MEM
>> config OF_RESOLVE
>> bool
>>
>> +config OF_OVERLAY
>> + bool
>> + depends on OF
>> + select OF_DYNAMIC
>> + select OF_DEVICE
>
> There's currently no Kconfig symbol OF_DEVICE. So this select is now a
> nop. Will that symbol be added in a future patch?

That's a hanger-on from an earlier version of the patch. I'll apply a
fixup patch to remove it.

g.
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