From: Daniel Thompson <daniel.thompson@linaro.org>
To: Jean-Jacques Hiblot <jjhiblot@ti.com>
Cc: Dan Murphy <dmurphy@ti.com>,
jacek.anaszewski@gmail.com, pavel@ucw.cz, robh+dt@kernel.org,
mark.rutland@arm.com, linux-leds@vger.kernel.org,
linux-kernel@vger.kernel.org, devicetree@vger.kernel.org
Subject: Re: [PATCH 1/2] leds: Add control of the voltage/current regulator to the LED core
Date: Mon, 15 Jul 2019 16:19:35 +0100 [thread overview]
Message-ID: <20190715151935.4ci23aqw4liz56fg@holly.lan> (raw)
In-Reply-To: <9c53f54f-d0d4-50d4-09da-34389085269a@ti.com>
On Mon, Jul 15, 2019 at 11:47:08AM +0200, Jean-Jacques Hiblot wrote:
> > > > > + if (IS_ERR(led_cdev->regulator)) {
> > > > > + dev_err(led_cdev->dev, "Cannot get the power supply for %s\n",
> > > > > + led_cdev->name);
> > > > > + device_unregister(led_cdev->dev);
> > > > > + mutex_unlock(&led_cdev->led_access);
> > > > > + return PTR_ERR(led_cdev->regulator);
> > > > This is listed as optional in the DT doc. This appears to be required.
> > > The regulator core will provide a dummy regulator if none is given in the
> > > device tree. I would rather have an error in that case, but that is not how
> > > it works.
> > If you actively wanted to get -ENODEV back when there is no regulator
> > then you can use devm_regulator_get_optional() for that.
> >
> > However perhaps be careful what you wish for. If you use get_optional()
> > then you will have to sprinkle NULL or IS_ERR() checks everywhere. I'd
> > favour using the current approach!
>
> Thanks for the info. I think I'll use the get_optionnal(). That will add a
> bit of complexity, but it will avoid deferring some work in
> led_set_brightness_nopm() when it is not needed.
Makes sense, I didn't notice that it allows you to avoid deferred work.
Daniel.
next prev parent reply other threads:[~2019-07-15 15:19 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-07-08 10:35 [PATCH 0/2] leds: Add control of the voltage/current regulator to the LED core Jean-Jacques Hiblot
2019-07-08 10:35 ` Jean-Jacques Hiblot
2019-07-08 10:35 ` [PATCH 1/2] " Jean-Jacques Hiblot
2019-07-08 10:35 ` Jean-Jacques Hiblot
2019-07-12 18:49 ` Dan Murphy
2019-07-12 18:49 ` Dan Murphy
2019-07-15 9:01 ` Jean-Jacques Hiblot
2019-07-15 9:24 ` Daniel Thompson
2019-07-15 9:47 ` Jean-Jacques Hiblot
2019-07-15 15:19 ` Daniel Thompson [this message]
2019-07-08 10:35 ` [PATCH 2/2] dt-bindings: leds: document new "power-supply" property Jean-Jacques Hiblot
2019-07-08 10:35 ` Jean-Jacques Hiblot
2019-07-12 18:38 ` Dan Murphy
2019-07-12 18:38 ` Dan Murphy
2019-07-24 16:47 ` Rob Herring
2019-07-25 11:08 ` Jean-Jacques Hiblot
2019-07-26 10:06 ` Daniel Thompson
2019-07-26 22:44 ` Rob Herring
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=20190715151935.4ci23aqw4liz56fg@holly.lan \
--to=daniel.thompson@linaro.org \
--cc=devicetree@vger.kernel.org \
--cc=dmurphy@ti.com \
--cc=jacek.anaszewski@gmail.com \
--cc=jjhiblot@ti.com \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-leds@vger.kernel.org \
--cc=mark.rutland@arm.com \
--cc=pavel@ucw.cz \
--cc=robh+dt@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).