From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from avon.wwwdotorg.org ([70.85.31.133]:55647 "EHLO avon.wwwdotorg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752714Ab3HLWne (ORCPT ); Mon, 12 Aug 2013 18:43:34 -0400 Message-ID: <52096511.4000804@wwwdotorg.org> Date: Mon, 12 Aug 2013 16:43:29 -0600 From: Stephen Warren MIME-Version: 1.0 Subject: Re: [PATCH] pwm-backlight: add "max-brightness" property References: <1376345057-29895-1-git-send-email-abrestic@chromium.org> In-Reply-To: <1376345057-29895-1-git-send-email-abrestic@chromium.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: devicetree-owner@vger.kernel.org To: Andrew Bresticker Cc: Richard Purdie , Jingoo Han , Olof Johansson , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Rob Landley , Thierry Reding , Jean-Christophe Plagniol-Villard , Tomi Valkeinen , devicetree@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pwm@vger.kernel.org, linux-fbdev@vger.kernel.org List-ID: On 08/12/2013 04:04 PM, Andrew Bresticker wrote: > Specifying each individual brightness value via the "brightness-levels" > property can be a pain if we want to use a large continuous range of > brightness values. Add the property "max-brightness", which can be > given in place of "brightness-levels", that specifies that all values > between 0 and the given value can be used. What about the non-linear nature of PWM duty cycle <-> (perceived) brightness level? That's why the values are typically enumerated. I guess if you use this new property, you'd use a value of say 16; exposing levels 0..255 to a user is probably more than they want?