From: Pavel Machek <pavel@ucw.cz>
To: Bryan Wu <cooloney@gmail.com>
Cc: "Måns Rullgård" <mans@mansr.com>,
"Geert Uytterhoeven" <geert@linux-m68k.org>,
"Alexandre Courbot" <gnurou@gmail.com>,
"Felipe Balbi" <balbi@ti.com>, "Bryan Wu" <cooloney@gmail.cofm>,
"Richard Purdie" <rpurdie@rpsys.net>,
"linux-leds@vger.kernel.org" <linux-leds@vger.kernel.org>,
"Linux Kernel Mailing List" <linux-kernel@vger.kernel.org>,
"Linux OMAP Mailing List" <linux-omap@vger.kernel.org>,
"linux-gpio@vger.kernel.org" <linux-gpio@vger.kernel.org>
Subject: Documentation: leds: clarify what 50% brightness means
Date: Wed, 11 Mar 2015 10:34:26 +0100 [thread overview]
Message-ID: <20150311093425.GA8866@amd> (raw)
In-Reply-To: <CAK5ve-K4jyBSVk1CZ8qQrFgevqdbhdsgZ1ZYX2e-t07494oq4A@mail.gmail.com>
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 <pavel@ucw.cz>
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/<led>/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/<led>/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
prev parent reply other threads:[~2015-03-11 9:34 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-02-19 21:14 "advanced" LED controllers Felipe Balbi
2015-02-19 21:14 ` Felipe Balbi
2015-02-23 22:34 ` Pavel Machek
2015-02-23 22:58 ` Felipe Balbi
2015-02-23 22:58 ` Felipe Balbi
2015-02-25 21:49 ` Pavel Machek
2015-02-25 23:55 ` NeilBrown
2015-02-28 16:18 ` Pavel Machek
2015-02-25 8:25 ` Geert Uytterhoeven
2015-02-25 9:06 ` Alexandre Courbot
2015-03-02 9:21 ` Pavel Machek
2015-03-03 8:15 ` Alexandre Courbot
2015-03-08 20:57 ` RGB LED control (was Re: "advanced" LED controllers) Pavel Machek
2015-03-09 8:08 ` Geert Uytterhoeven
2015-03-09 9:08 ` Pavel Machek
2015-03-09 11:50 ` Måns Rullgård
2015-03-09 11:50 ` Måns Rullgård
2015-03-10 8:04 ` Pavel Machek
[not found] ` <CAK5ve-K4jyBSVk1CZ8qQrFgevqdbhdsgZ1ZYX2e-t07494oq4A@mail.gmail.com>
2015-03-11 9:34 ` Pavel Machek [this message]
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