All of lore.kernel.org
 help / color / mirror / Atom feed
From: Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org>
To: Rob Herring <robherring2-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
Cc: Jean-Francois Moine <moinejf-GANU6spQydw@public.gmane.org>,
	"devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org"
	<devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org>,
	alsa-devel-K7yf7f+aM1XWsZ/bQMPhNw@public.gmane.org,
	Takashi Iwai <tiwai-l3A5Bk7waGM@public.gmane.org>,
	Liam Girdwood <lgirdwood-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>,
	Jaroslav Kysela <perex-/Fr2/VpizcU@public.gmane.org>,
	Mark Brown <broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
	"linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org"
	<linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org>
Subject: Re: [PATCH] ASoC: generic: Add generic DT based simple codec
Date: Mon, 30 Sep 2013 10:49:06 -0600	[thread overview]
Message-ID: <5249AB82.60701@wwwdotorg.org> (raw)
In-Reply-To: <CAL_JsqKmfurrCqEYRNqcLRZMU-VjPin2dvK1Q6CMcK4i=+x-8w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>

On 09/26/2013 08:57 PM, Rob Herring wrote:
> On Mon, Sep 23, 2013 at 4:19 PM, Stephen Warren <swarren-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org> wrote:
>> On 09/19/2013 02:54 AM, Jean-Francois Moine wrote:
>>> This patch adds a simple sound codec which is described by the DT.
>>> This codec may be used when no specific codec action is needed.
>>
>>> diff --git a/Documentation/devicetree/bindings/sound/simple-codec.txt b/Documentation/devicetree/bindings/sound/simple-codec.txt
>>
>>> +Device-Tree bindings for the simple codec
>>> +
>>> +Required properties:
>>> +- compatible: should be "linux,simple-codec".
>>
>> We shouldn't have any Linux-specific bindings. It might be reasonable to
>> define a binding for a "simple CODEC", but there's no reason it should
>> be Linux-specific.
> 
> Further, just define the type of codec h/w. If linux can use its
> simple-codec driver for it, then add a match table entry for said
> codec. Then the DT is future proof when you decide the simple driver
> doesn't really work for that h/w.

The only potential issue with that approach is if the CODEC can be used
in a "simple" mode where e.g. no control GPIOs, regulator manipulation,
etc. are required, or in a more complex mode where such things are
required, you may end up with the device-specific binding being written
to the simple mode, and hence missing features required for the complex
mode. Having a separate simple binding prevents the device-specific
binding from being broken that way.

That said, it's probably better to simply get the device-specific
binding completely fleshed out and representing all resources the first
time around, then there's no issue either.

--
To unsubscribe from this list: send the line "unsubscribe devicetree" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

WARNING: multiple messages have this Message-ID (diff)
From: swarren@wwwdotorg.org (Stephen Warren)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] ASoC: generic: Add generic DT based simple codec
Date: Mon, 30 Sep 2013 10:49:06 -0600	[thread overview]
Message-ID: <5249AB82.60701@wwwdotorg.org> (raw)
In-Reply-To: <CAL_JsqKmfurrCqEYRNqcLRZMU-VjPin2dvK1Q6CMcK4i=+x-8w@mail.gmail.com>

On 09/26/2013 08:57 PM, Rob Herring wrote:
> On Mon, Sep 23, 2013 at 4:19 PM, Stephen Warren <swarren@wwwdotorg.org> wrote:
>> On 09/19/2013 02:54 AM, Jean-Francois Moine wrote:
>>> This patch adds a simple sound codec which is described by the DT.
>>> This codec may be used when no specific codec action is needed.
>>
>>> diff --git a/Documentation/devicetree/bindings/sound/simple-codec.txt b/Documentation/devicetree/bindings/sound/simple-codec.txt
>>
>>> +Device-Tree bindings for the simple codec
>>> +
>>> +Required properties:
>>> +- compatible: should be "linux,simple-codec".
>>
>> We shouldn't have any Linux-specific bindings. It might be reasonable to
>> define a binding for a "simple CODEC", but there's no reason it should
>> be Linux-specific.
> 
> Further, just define the type of codec h/w. If linux can use its
> simple-codec driver for it, then add a match table entry for said
> codec. Then the DT is future proof when you decide the simple driver
> doesn't really work for that h/w.

The only potential issue with that approach is if the CODEC can be used
in a "simple" mode where e.g. no control GPIOs, regulator manipulation,
etc. are required, or in a more complex mode where such things are
required, you may end up with the device-specific binding being written
to the simple mode, and hence missing features required for the complex
mode. Having a separate simple binding prevents the device-specific
binding from being broken that way.

That said, it's probably better to simply get the device-specific
binding completely fleshed out and representing all resources the first
time around, then there's no issue either.

  parent reply	other threads:[~2013-09-30 16:49 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-09-19  8:54 [PATCH] ASoC: generic: Add generic DT based simple codec Jean-Francois Moine
2013-09-19  8:54 ` Jean-Francois Moine
2013-09-19 10:40 ` Mark Brown
2013-09-19 10:40   ` Mark Brown
     [not found]   ` <20130919104028.GI21013-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2013-09-19 17:34     ` Jean-Francois Moine
2013-09-19 17:34       ` Jean-Francois Moine
2013-09-19 17:49       ` Russell King - ARM Linux
2013-09-19 17:49         ` Russell King - ARM Linux
     [not found]         ` <20130919174952.GC12758-l+eeeJia6m9vn6HldHNs0ANdhmdF6hFW@public.gmane.org>
2013-09-19 18:12           ` Mark Brown
2013-09-19 18:12             ` Mark Brown
2013-09-19 18:05       ` Mark Brown
2013-09-19 18:05         ` Mark Brown
2013-09-23 21:19 ` Stephen Warren
2013-09-23 21:19   ` Stephen Warren
     [not found]   ` <5240B07C.6080404-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org>
2013-09-23 23:26     ` Mark Brown
2013-09-23 23:26       ` Mark Brown
     [not found]       ` <20130923232648.GL21013-GFdadSzt00ze9xe1eoZjHA@public.gmane.org>
2013-09-26 23:16         ` Stephen Warren
2013-09-26 23:16           ` Stephen Warren
2013-09-27  2:57     ` Rob Herring
2013-09-27  2:57       ` Rob Herring
2013-09-27  9:55       ` Mark Brown
2013-09-27  9:55         ` Mark Brown
     [not found]       ` <CAL_JsqKmfurrCqEYRNqcLRZMU-VjPin2dvK1Q6CMcK4i=+x-8w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2013-09-30 16:49         ` Stephen Warren [this message]
2013-09-30 16:49           ` Stephen Warren
     [not found]           ` <5249AB82.60701-3lzwWm7+Weoh9ZMKESR00Q@public.gmane.org>
2013-09-30 17:43             ` Mark Brown
2013-09-30 17:43               ` Mark Brown

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=5249AB82.60701@wwwdotorg.org \
    --to=swarren-3lzwwm7+weoh9zmkesr00q@public.gmane.org \
    --cc=alsa-devel-K7yf7f+aM1XWsZ/bQMPhNw@public.gmane.org \
    --cc=broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org \
    --cc=devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    --cc=lgirdwood-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org \
    --cc=linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org \
    --cc=moinejf-GANU6spQydw@public.gmane.org \
    --cc=perex-/Fr2/VpizcU@public.gmane.org \
    --cc=robherring2-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org \
    --cc=tiwai-l3A5Bk7waGM@public.gmane.org \
    /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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.