From: Stephen Warren <swarren@wwwdotorg.org>
To: Laxman Dewangan <ldewangan@nvidia.com>
Cc: J Keerthy <j-keerthy@ti.com>,
"grant.likely@secretlab.ca" <grant.likely@secretlab.ca>,
"rob.herring@calxeda.com" <rob.herring@calxeda.com>,
"rob@landley.net" <rob@landley.net>,
"devicetree-discuss@lists.ozlabs.org"
<devicetree-discuss@lists.ozlabs.org>,
"linux-doc@vger.kernel.org" <linux-doc@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"b-cousson@ti.com" <b-cousson@ti.com>,
"gg@slimlogic.co.uk" <gg@slimlogic.co.uk>
Subject: Re: [PATCH 1/4] documentation: add palmas dts definition
Date: Thu, 28 Feb 2013 11:51:22 -0700 [thread overview]
Message-ID: <512FA72A.4060303@wwwdotorg.org> (raw)
In-Reply-To: <512F1ADF.90906@nvidia.com>
On 02/28/2013 01:52 AM, Laxman Dewangan wrote:
> On Thursday 28 February 2013 12:02 AM, Stephen Warren wrote:
>> On 02/17/2013 10:11 PM, J Keerthy wrote:
>> +- interrupt-parent : The parent interrupt controller.
>> +
>> +Optional node:
>> +- Child nodes contain in the palmas. The palmas family is made of
>> several
>> + variants that support a different number of features.
>> + The child nodes will thus depend of the capability of the variant.
>> Are there DT bindings for those child nodes anywhere?
>>
>> Representing each internal component as a separate DT node feels a
>> little like designing the DT bindings to model the Linux-internal MFD
>> structure. DT bindings should be driven by the HW design and OS-agnostic.
>>
>> From a DT perspective, is there any need at all to create a separate DT
>> node for each component? This would only be needed or useful if the
>> child IP blocks (and hence DT bindings for those blocks) could be
>> re-used in other top-level devices that aren't represented by this
>> top-level ti,palmas DT binding. Are the HW IP blocks here re-used
>> anywhere, or will they be?
>
>
> I dont think that child IP block can be used outside of the palma
> although other mfd device may have same IP.
That sounds like pretty much the definition of re-using the IP block...
> The child driver very much used the palma's API for register access and
> they can not be separated untill driver is write completely independent
> of palmas API. Currently, child driver include the palma header, uses
> palma mfd stcruture and plama's api for accessing registers.
The DT binding and compatible values should not be influenced by
OS-specific driver implementation details. DT bindings are supposed to
be (as near as possible) a pure HW description, which (many different)
OSs parse, and map to their internal driver structure as appropriate.
The above is of course just a comment on how DT is supposed to work; I'm
not saying anything here re: what's the most appropriate DT structure
for this device.
>>> + palmas_pmic {
>> Just "pmic" seems simpler, although I dare say the node name isn't
>> really used for anything.
>
> Stephen,
> Just curios, why do we require the palma_pmic node at all, We can start
> with regulator node directly. Is it not too much nested here?
That was the question I was asking in my original email. But I also
commented on the patch as written, in case the answer to my question was
that the child DT nodes made sense.
next prev parent reply other threads:[~2013-02-28 18:51 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-02-18 5:11 [PATCH 1/4] documentation: add palmas dts definition J Keerthy
2013-02-27 18:32 ` Stephen Warren
2013-02-28 8:52 ` Laxman Dewangan
2013-02-28 9:58 ` Graeme Gregory
2013-02-28 10:27 ` Laxman Dewangan
2013-02-28 10:57 ` Graeme Gregory
2013-02-28 11:21 ` Graeme Gregory
2013-02-28 19:01 ` Stephen Warren
2013-02-28 18:58 ` Stephen Warren
2013-02-28 18:51 ` Stephen Warren [this message]
2013-02-28 12:09 ` J, KEERTHY
2013-02-28 19:07 ` Stephen Warren
2013-03-01 2:24 ` J, KEERTHY
2013-02-20 4:00 J Keerthy
2013-02-20 11:26 ` Mark Brown
2013-02-20 13:49 ` J, KEERTHY
2013-02-27 18:16 ` Stephen Warren
2013-03-02 4:07 ` Mark Brown
2013-02-25 8:55 ` J, KEERTHY
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=512FA72A.4060303@wwwdotorg.org \
--to=swarren@wwwdotorg.org \
--cc=b-cousson@ti.com \
--cc=devicetree-discuss@lists.ozlabs.org \
--cc=gg@slimlogic.co.uk \
--cc=grant.likely@secretlab.ca \
--cc=j-keerthy@ti.com \
--cc=ldewangan@nvidia.com \
--cc=linux-doc@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=rob.herring@calxeda.com \
--cc=rob@landley.net \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).