linux-arm-kernel.lists.infradead.org archive mirror
 help / color / mirror / Atom feed
From: broonie@opensource.wolfsonmicro.com (Mark Brown)
To: linux-arm-kernel@lists.infradead.org
Subject: [PATCH] backlight: add regulator support for platform_lcd driver
Date: Mon, 5 Dec 2011 10:52:02 +0000	[thread overview]
Message-ID: <20111205105201.GD11150@opensource.wolfsonmicro.com> (raw)
In-Reply-To: <CAJuYYwTT2jbbquZM=ZwK=Gh39ss=iG0WDCc3TYjzHLEgfeC1gA@mail.gmail.com>

On Mon, Dec 05, 2011 at 04:06:17PM +0530, Thomas Abraham wrote:
> On 5 December 2011 15:40, Kyungmin Park <kmpark@infradead.org> wrote:

> > Recent regulator discussion. it should be failed instead fall through
> > gracefully.

> Ok. But in this case, there could be boards that do not use a
> regulator for the lcd/display interface. Is it mandatory for fail if
> regulator is not found. Sorry, I have not read through the regulator
> discussion.

The boards should supply a fixed voltage regulator representing the
supply (or use CONFIG_REGULATOR_DUMMY to substitute in a dummy regulator
when not needed).  Sascha Hauer had some patches to add a flag that
could be set to enable this mode on init rather than through Kconfig but
they needed a bit of cleanup, not sure what the status is there.

> The constraint 'apply_uV' cannot be expressed with a device tree. So
> there has be a mechanism to set the required output voltage for a
> regulator.

It's not an option to not have it with device tree - if there's a single
voltage specified apply_uV is assumed.

      reply	other threads:[~2011-12-05 10:52 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2011-12-05  8:48 [PATCH] backlight: add regulator support for platform_lcd driver Thomas Abraham
2011-12-05  8:52 ` Felipe Balbi
2011-12-05  9:14   ` Thomas Abraham
2011-12-05 10:10 ` Kyungmin Park
2011-12-05 10:33   ` Mark Brown
2011-12-05 10:36   ` Thomas Abraham
2011-12-05 10:52     ` 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=20111205105201.GD11150@opensource.wolfsonmicro.com \
    --to=broonie@opensource.wolfsonmicro.com \
    --cc=linux-arm-kernel@lists.infradead.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).