Linux-LEDs Archive on lore.kernel.org
 help / color / Atom feed
From: Dan Murphy <dmurphy@ti.com>
To: Jean-Jacques Hiblot <jjhiblot@ti.com>,
	<jacek.anaszewski@gmail.com>, <pavel@ucw.cz>,
	<robh+dt@kernel.org>, <mark.rutland@arm.com>,
	<daniel.thompson@linaro.org>
Cc: <linux-leds@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
	<devicetree@vger.kernel.org>
Subject: Re: [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core
Date: Mon, 15 Jul 2019 13:59:27 -0500
Message-ID: <9c17e9cc-8162-7b5d-2db9-d2bed20969c5@ti.com> (raw)
In-Reply-To: <20190715155657.22976-3-jjhiblot@ti.com>

JJ

On 7/15/19 10:56 AM, Jean-Jacques Hiblot wrote:
> A LED is usually powered by a voltage/current regulator. Let the LED core
> know about it. This allows the LED core to turn on or off the power supply
> as needed.

This allows the LED core to turn on or off managed power supplies.


>
> Signed-off-by: Jean-Jacques Hiblot <jjhiblot@ti.com>
> ---
>   drivers/leds/led-class.c | 15 ++++++++++++
>   drivers/leds/led-core.c  | 50 +++++++++++++++++++++++++++++++++++++---
>   drivers/leds/leds.h      |  1 +
>   include/linux/leds.h     |  4 ++++
>   4 files changed, 67 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
> index 4793e77808e2..cadd43c30d50 100644
> --- a/drivers/leds/led-class.c
> +++ b/drivers/leds/led-class.c
> @@ -253,6 +253,7 @@ int of_led_classdev_register(struct device *parent, struct device_node *np,
>   {
>   	char name[LED_MAX_NAME_SIZE];
>   	int ret;
> +	struct regulator *regulator;
>   
>   	ret = led_classdev_next_name(led_cdev->name, name, sizeof(name));
>   	if (ret < 0)
> @@ -272,6 +273,20 @@ int of_led_classdev_register(struct device *parent, struct device_node *np,
>   		dev_warn(parent, "Led %s renamed to %s due to name collision",
>   				led_cdev->name, dev_name(led_cdev->dev));
>   
> +	regulator = devm_regulator_get_optional(led_cdev->dev, "power");
Store the regulator in  led_cdev->regulator and drop the else case below.
> +	if (IS_ERR(regulator)) {
> +		if (PTR_ERR(regulator) != -ENODEV) {
> +			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(regulator);
> +		}
> +		led_cdev->regulator = NULL;
> +	} else {
> +		led_cdev->regulator = regulator;
> +	}
> +
>   	if (led_cdev->flags & LED_BRIGHT_HW_CHANGED) {
>   		ret = led_add_brightness_hw_changed(led_cdev);
>   		if (ret) {
> diff --git a/drivers/leds/led-core.c b/drivers/leds/led-core.c
> index 7107cd7e87cf..a12b880b0a2f 100644
> --- a/drivers/leds/led-core.c
> +++ b/drivers/leds/led-core.c
> @@ -23,6 +23,33 @@ EXPORT_SYMBOL_GPL(leds_list_lock);
>   LIST_HEAD(leds_list);
>   EXPORT_SYMBOL_GPL(leds_list);
>   
> +static bool __led_need_regulator_update(struct led_classdev *led_cdev,
> +					int brightness)
> +{
> +	bool new_state = (brightness != LED_OFF);
> +
> +	return led_cdev->regulator && led_cdev->regulator_state != new_state;
> +}
> +
> +static int __led_handle_regulator(struct led_classdev *led_cdev,
> +				int brightness)
> +{
> +	int rc;

Should there be a check for the regulator pointer.

If (!led_cdev->regulator)

     return 0;


Otherwise

Reviewed-by: Dan Murphy <dmurphy@ti.com>

<snip>


  reply index

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-07-15 15:56 [PATCH v2 0/2] " Jean-Jacques Hiblot
2019-07-15 15:56 ` [PATCH v2 1/2] dt-bindings: leds: document the "power-supply" property Jean-Jacques Hiblot
2019-07-15 18:52   ` Dan Murphy
2019-08-19 11:31   ` Pavel Machek
2019-07-15 15:56 ` [PATCH v2 2/2] leds: Add control of the voltage/current regulator to the LED core Jean-Jacques Hiblot
2019-07-15 18:59   ` Dan Murphy [this message]
2019-07-17 13:14     ` Jean-Jacques Hiblot
2019-07-15 20:42   ` Jacek Anaszewski
2019-07-17 13:23     ` Jean-Jacques Hiblot
2019-07-16 10:50   ` Daniel Thompson
2019-07-17 13:47     ` Jean-Jacques Hiblot

Reply instructions:

You may reply publically 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=9c17e9cc-8162-7b5d-2db9-d2bed20969c5@ti.com \
    --to=dmurphy@ti.com \
    --cc=daniel.thompson@linaro.org \
    --cc=devicetree@vger.kernel.org \
    --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

Linux-LEDs Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-leds/0 linux-leds/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-leds linux-leds/ https://lore.kernel.org/linux-leds \
		linux-leds@vger.kernel.org linux-leds@archiver.kernel.org
	public-inbox-index linux-leds


Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-leds


AGPL code for this site: git clone https://public-inbox.org/ public-inbox