From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Subject: RGB LED control (was Re: "advanced" LED controllers) Date: Sun, 8 Mar 2015 21:57:32 +0100 Message-ID: <20150308205732.GA385@amd> References: <20150219211424.GN13603@saruman.tx.rr.com> <20150302092111.GA19233@amd> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-leds-owner@vger.kernel.org To: Alexandre Courbot Cc: Geert Uytterhoeven , Felipe Balbi , Bryan Wu , Richard Purdie , "linux-leds@vger.kernel.org" , Linux Kernel Mailing List , Linux OMAP Mailing List , "linux-gpio@vger.kernel.org" List-Id: linux-gpio@vger.kernel.org Ok, so I played with RGB LED a bit, and we have quite a gap in documentation: what 50% brightness means is non-trivial and very important in case we want to do smooth blinking and color transitions. Signed-off-by: Pavel Machek diff --git a/Documentation/ABI/testing/sysfs-class-led b/Documentation/ABI/testing/sysfs-class-led index 3646ec8..649d7a6 100644 --- a/Documentation/ABI/testing/sysfs-class-led +++ b/Documentation/ABI/testing/sysfs-class-led @@ -8,6 +8,11 @@ Description: non-zero brightness settings. The value is between 0 and /sys/class/leds//max_brightness. + If LED supports continuous brightness settings, 50% brightness + should correspond to 50% brightness perceived by human, in a similar + manner pixel brightness on monitor does (not 50% PWM). + + What: /sys/class/leds//max_brightness Date: March 2006 KernelVersion: 2.6.17 -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html