From mboxrd@z Thu Jan 1 00:00:00 1970 From: Brian Masney Subject: Re: [PATCH 1/2] dt-bindings: trivial: add ti,lm3630a binding Date: Fri, 30 Nov 2018 09:25:40 -0500 Message-ID: <20181130142540.GB27500@basecamp> References: <20181124141703.29232-1-masneyb@onstation.org> <20181127105642.uu56phxjfl7bjl2p@holly.lan> <20181130135927.GA27500@basecamp> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: linux-kernel-owner@vger.kernel.org To: Rob Herring Cc: Daniel Thompson , Lee Jones , Jingoo Han , Mark Rutland , Bartlomiej Zolnierkiewicz , dri-devel , linux-fbdev@vger.kernel.org, devicetree@vger.kernel.org, "linux-kernel@vger.kernel.org" , Jonathan Marek , Craig Tatlor , Dan Murphy List-Id: devicetree@vger.kernel.org On Fri, Nov 30, 2018 at 08:13:04AM -0600, Rob Herring wrote: > > > It's quite unusual for a backlight device to have a trivial binding. > > > > > > The driver supports fairly extensive parametrization via struct > > > lm3530a_platform_data. It is really the case that none of these > > > properties should ever be set via DT? > > > > Hi Daniel, > > > > I initially assumed that we would let user space configure these values > > once the system has booted, but you are right that these should be > > available in device tree. > > > > The driver has two different LED banks that can be configured > > independently. > > That is usually represented with child nodes which makes this anything > but trivial. Plus, given that we have bindings for LEDs/backlights, no > LED/backlight controller is a trivial device. Hi Rob, I agree and I'm not going to use a trivial binding for v2. See below for some questions that I have from my last email. > > How do you feel about having a single property in > > device tree populate the initial values for both banks? I propose that > > we could use the property default-brightness-level for leda_init_brt > > and ledb_init_brt in struct lm3630a_platform_data. The max-brightness > > property can populate leda_max_brt and ledb_max_brt. > > > > I need to look at other bindings this weekend to see if there are any > > standard properties that I can use for leda_ctrl/ledb_ctrl, pwm_ctrl, > > and pwm_period. > > > > Brian > >