All of lore.kernel.org
 help / color / mirror / Atom feed
From: Pavel Machek <pavel@ucw.cz>
To: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Dan Murphy <dmurphy@ti.com>,
	linux-leds@vger.kernel.org, linux-kernel@vger.kernel.org,
	devicetree@vger.kernel.org, dachaac@gmail.com,
	robh+dt@kernel.org
Subject: Re: RGB LED class Re: [PATCH v2 2/2] leds: lp50xx: Add the LP50XX family of the RGB LED driver
Date: Tue, 29 Jan 2019 00:04:08 +0100	[thread overview]
Message-ID: <20190128230408.GB5728@amd> (raw)
In-Reply-To: <9d2e0220-69f0-faaa-adb9-13d905f9c51d@gmail.com>

[-- Attachment #1: Type: text/plain, Size: 1402 bytes --]

Hi!

> >>What algorithm would be used for mapping brightness levels to RGB values
> >>in case of devices without hardware support for that?
> >
> >Output power = brightness / max_brightness * pwm_channel[x].
> 
> IIUC you mean it as a formula for calculating r,g,b, values?
> I.e., on brightness setting we would have to do this calculation for
> each of three channels?
> 
> Then, it will result in changing hue as well. That's why we're
> discussing HSV.

It should not change the hue, AFAICT, modulo the rounding errors.

> >>s/pwm/color/
> >
> >s/pwm/power/ would work for me.
> 
> Power implies physical units. I'd prefer "intensity".

Intensity would work for me, too.

> >>Besides white also other color presets could be defined in DT.
> >
> >They should not be neccessary. When userspace knows what is white and
> >that power is linear with values in power_channels, it should be able
> >to do colorspace conversion itself.
> 
> Have you verified it in practice? Would it allow to convert RGB values
> of the color displayed on the monitor to LED RGB class intensities,
> allowing to achieve similar color on the LED?

Yes, I think so.

My code is in unicsy_demo repository, in monitor/notint.py .


									Pavel
-- 
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

[-- Attachment #2: Digital signature --]
[-- Type: application/pgp-signature, Size: 181 bytes --]

  parent reply	other threads:[~2019-01-28 23:04 UTC|newest]

Thread overview: 60+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-01-14 21:17 [PATCH v2 1/2] dt: bindings: lp50xx: Introduce the lp50xx family of RGB drivers Dan Murphy
2019-01-14 21:17 ` Dan Murphy
2019-01-14 21:17 ` [PATCH v2 2/2] leds: lp50xx: Add the LP50XX family of the RGB LED driver Dan Murphy
2019-01-14 21:17   ` Dan Murphy
2019-01-15 21:47   ` Jacek Anaszewski
2019-01-15 22:22     ` Pavel Machek
2019-01-16  0:20       ` Dan Murphy
2019-01-16  0:20         ` Dan Murphy
2019-01-16 10:55         ` Pavel Machek
2019-01-16 18:41           ` Dan Murphy
2019-01-16 18:41             ` Dan Murphy
2019-01-16 22:04             ` Pavel Machek
2019-01-16 23:33               ` Dan Murphy
2019-01-16 23:33                 ` Dan Murphy
2019-01-17 10:06                 ` Pavel Machek
2019-01-17 13:27                   ` Dan Murphy
2019-01-17 13:27                     ` Dan Murphy
2019-01-17 21:10             ` Jacek Anaszewski
2019-01-18  0:02               ` RGB LED class " Pavel Machek
2019-01-18 15:57                 ` Dan Murphy
2019-01-18 15:57                   ` Dan Murphy
2019-01-28 23:03                   ` Pavel Machek
2019-01-18 22:13                 ` Jacek Anaszewski
2019-01-19 21:36                   ` Pavel Machek
2019-01-20 15:30                     ` Jacek Anaszewski
2019-01-21 19:38                       ` Jacek Anaszewski
2019-01-28 23:04                       ` Pavel Machek [this message]
2019-01-18 13:45               ` Dan Murphy
2019-01-18 13:45                 ` Dan Murphy
2019-01-18 13:58                 ` Dan Murphy
2019-01-18 13:58                   ` Dan Murphy
2019-01-20  6:42                   ` Vesa Jääskeläinen
2019-01-22 21:39                     ` Jacek Anaszewski
2019-01-22 22:44                       ` Dan Murphy
2019-01-22 22:44                         ` Dan Murphy
2019-01-23 21:52                         ` Jacek Anaszewski
2019-01-24 21:00                           ` Dan Murphy
2019-01-24 21:00                             ` Dan Murphy
2019-01-24 21:55                             ` Jacek Anaszewski
2019-01-29 13:56                               ` Dan Murphy
2019-01-29 13:56                                 ` Dan Murphy
2019-01-29 20:19                                 ` Jacek Anaszewski
2019-01-29 20:26                                   ` Dan Murphy
2019-01-29 20:26                                     ` Dan Murphy
2019-01-29 21:45                                     ` Pavel Machek
2019-01-29 21:46                                       ` Dan Murphy
2019-01-29 21:53                                     ` Jacek Anaszewski
2019-01-20 15:32                 ` Jacek Anaszewski
2019-01-17 21:08           ` Jacek Anaszewski
2019-01-19 19:11             ` Vesa Jääskeläinen
2019-01-19 21:46               ` Pavel Machek
2019-01-19 22:44                 ` Vesa Jääskeläinen
2019-01-20  6:51                 ` Vesa Jääskeläinen
2019-01-21 13:27               ` Dan Murphy
2019-01-21 13:27                 ` Dan Murphy
2019-01-21 15:12                 ` Vesa Jääskeläinen
2019-01-24 20:32     ` Dan Murphy
2019-01-24 20:32       ` Dan Murphy
2019-01-24 21:14       ` Jacek Anaszewski
2019-01-15 21:42 ` [PATCH v2 1/2] dt: bindings: lp50xx: Introduce the lp50xx family of RGB drivers Jacek Anaszewski

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=20190128230408.GB5728@amd \
    --to=pavel@ucw.cz \
    --cc=dachaac@gmail.com \
    --cc=devicetree@vger.kernel.org \
    --cc=dmurphy@ti.com \
    --cc=jacek.anaszewski@gmail.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-leds@vger.kernel.org \
    --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 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.