linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Mark Brown <broonie@opensource.wolfsonmicro.com>
To: Lars-Peter Clausen <lars@metafoo.de>
Cc: Laxman Dewangan <ldewangan@nvidia.com>,
	gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org,
	linux-tegra@vger.kernel.org
Subject: Re: [PATCH V1] regmap: Support for caching in reg_raw_write()
Date: Fri, 10 Feb 2012 15:58:32 +0000	[thread overview]
Message-ID: <20120210155831.GE6472@opensource.wolfsonmicro.com> (raw)
In-Reply-To: <4F350E8C.6030907@metafoo.de>

[-- Attachment #1: Type: text/plain, Size: 1031 bytes --]

On Fri, Feb 10, 2012 at 01:33:16PM +0100, Lars-Peter Clausen wrote:

> regmap_write doesn't always go the raw_write path. Also with this approach

We can ignore the non-byte formats as a wart for this; they're cut out
of this area of the subsystem functionality and just get single register
write operatons with single register cache access.

> we end up formatting the value into the raw format, only to parse it again
> in the next step.

Yes, like I say there's room for optimisation.  For 8 bit values there
would be win from working out that we don't need to do anything at all, 
though I doubt it's ever going to be performance critical.

> Furthermore I don't think it makes sense to cache raw values as the cache
> operates on a register level, not on a byte level.

The entire API operates on registers really.  The only reason
raw_write() takes a length is because it's what most of the users are
actually likely to have to hand, trying to write to less than a register
isn't particularly sensible.

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 836 bytes --]

      reply	other threads:[~2012-02-10 15:58 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-02-10 11:32 [PATCH V1] regmap: Support for caching in reg_raw_write() Laxman Dewangan
2012-02-10 11:45 ` Mark Brown
2012-02-10 12:01 ` Lars-Peter Clausen
2012-02-10 12:07   ` Laxman Dewangan
2012-02-10 12:14   ` Mark Brown
2012-02-10 12:33     ` Lars-Peter Clausen
2012-02-10 15:58       ` Mark Brown [this message]

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=20120210155831.GE6472@opensource.wolfsonmicro.com \
    --to=broonie@opensource.wolfsonmicro.com \
    --cc=gregkh@linuxfoundation.org \
    --cc=lars@metafoo.de \
    --cc=ldewangan@nvidia.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-tegra@vger.kernel.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 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).