From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756951Ab2HPSmb (ORCPT ); Thu, 16 Aug 2012 14:42:31 -0400 Received: from avon.wwwdotorg.org ([70.85.31.133]:59845 "EHLO avon.wwwdotorg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751585Ab2HPSm3 (ORCPT ); Thu, 16 Aug 2012 14:42:29 -0400 Message-ID: <502D3F10.1020509@wwwdotorg.org> Date: Thu, 16 Aug 2012 12:42:24 -0600 From: Stephen Warren User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:14.0) Gecko/20120714 Thunderbird/14.0 MIME-Version: 1.0 To: Alexandre Courbot CC: Stephen Warren , Thierry Reding , Simon Glass , Grant Likely , Rob Herring , Mark Brown , Anton Vorontsov , David Woodhouse , Arnd Bergmann , Leela Krishna Amudala , linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org, linux-fbdev@vger.kernel.org, devicetree-discuss@lists.ozlabs.org, linux-doc@vger.kernel.org Subject: Re: [PATCH v4 2/3] pwm_backlight: use power sequences References: <1345097337-24170-1-git-send-email-acourbot@nvidia.com> <1345097337-24170-3-git-send-email-acourbot@nvidia.com> In-Reply-To: <1345097337-24170-3-git-send-email-acourbot@nvidia.com> X-Enigmail-Version: 1.5a1pre Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/16/2012 12:08 AM, Alexandre Courbot wrote: > Make use of the power sequences specified in the device tree or platform > data to control how the backlight is powered on and off. > +++ b/Documentation/devicetree/bindings/video/backlight/pwm-backlight.txt > Required properties: > - compatible: "pwm-backlight" > - - pwms: OF device-tree PWM specification (see PWM binding[0]) > - brightness-levels: Array of distinct brightness levels. Typically these > are in the range from 0 to 255, but any range starting at 0 will do. > The actual brightness level (PWM duty cycle) will be interpolated > @@ -10,19 +9,72 @@ Required properties: > last value in the array represents a 100% duty cycle (brightest). > - default-brightness-level: the default brightness level (index into the > array defined by the "brightness-levels" property) > + - pwms: OF device-tree PWM specification (see PWM binding[0]). Exactly one PWM > + must be specified There's probably no need to move that entry just to change it? > Optional properties: > - - pwm-names: a list of names for the PWM devices specified in the > - "pwms" property (see PWM binding[0]) > + - *-supply: regulators used within a power sequence > + - *-gpio: GPIOs used within a power sequence I don't think these really warrant mentioning here; such properties are part of the standard regulator and GPIO bindings, and are required as a side-effect of a power sequence using a resource of those types, rather than being something actively defined or needed directly by the pwm-backlight binding. > + - pwm-names: name for the PWM device specified in the "pwms" property (see PWM > + binding[0]). Necessary if power sequences are used > + - power-on-sequence: Power sequence (see Power sequences[1]) used to bring the > + backlight on. This sequence must reference the PWM specified in the pwms > + property by its name. It can also reference other resources supported by > + the power sequences mechanism > + - power-off-sequence: Power sequence (see Power sequences[1]) used to bring > + the backlight off. This sequence must reference the PWM specified in the > + pwms property by its name. It can also reference other resources supported > + by the power sequences mechanism For these two, I would personally simply say that the pwm-backlight binding requires that two power sequences named "on" and "off" must exists, and are to defined according to [1]. > [0]: Documentation/devicetree/bindings/pwm/pwm.txt > +[1]: Documentation/devicetree/bindings/power_seq/power_seq.txt