From mboxrd@z Thu Jan 1 00:00:00 1970 From: Philipp Zabel Subject: Re: [PATCH] ARM: dts: imx6qdl: Adjust the brightness setting for LVDS panel Date: Tue, 27 Jan 2015 16:21:57 +0100 Message-ID: <1422372117.3751.58.camel@pengutronix.de> References: <1421749355-23050-1-git-send-email-r63905@freescale.com> <20150120113837.GC2766@dragon> <1421941084.3084.45.camel@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: Received: from metis.ext.pengutronix.de ([92.198.50.35]:48343 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751888AbbA0PWD (ORCPT ); Tue, 27 Jan 2015 10:22:03 -0500 In-Reply-To: Sender: linux-pwm-owner@vger.kernel.org List-Id: linux-pwm@vger.kernel.org To: "Robby.Cai@freescale.com" Cc: Shawn Guo , "linux-pwm@vger.kernel.org" , Eric Nelson , Tim Harvey , "jg1.han@samsung.com" , Troy Kisky , "thierry.reding@gmail.com" , "kernel@pengutronix.de" , "lee.jones@linaro.org" , "linux-arm-kernel@lists.infradead.org" Am Montag, den 26.01.2015, 14:44 +0000 schrieb Robby.Cai@freescale.com: > > I notice that the intervals are changed from exponential to linear. > > Is this really wanted here? > > I expect that the new settings result in huge steps in perceived > > brightness at low levels and a nearly imperceptible change at the last > > step. > > > > regards > > Philipp > > > No particular reason here. I understand your concern but seems there's no obvious rule. > How about add some interpolation, such as <0 52 64 96 128 160 192 224 255> > or even more, <0 52 64 80 96 112 128 144 160 176 192 208 224 240 255> I just wanted to point out the possible issue. Maybe somebody with the actual panel could sit down and experiment and come up with some visually pleasing steps. regards Philipp