From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Subject: Re: Reg: Adding a gpio initialization sequence in dts is valid or not Date: Fri, 17 Aug 2012 09:13:57 -0600 Message-ID: <502E5FB5.3060307@wwwdotorg.org> References: <502269EC.2070008@gmail.com> <502287E1.3040508@wwwdotorg.org> <50231B55.6070007@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Sender: "devicetree-discuss" To: Leela Krishna Amudala Cc: "devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org" , "thomas.ab-Sze3O3UU22JBDgjK7y7TUQ@public.gmane.org" , Alex Courbot List-Id: devicetree@vger.kernel.org On 08/17/2012 04:37 AM, Leela Krishna Amudala wrote: > Hello, > > I think you misinterpreted my question. > ... > But I don't bother about enabling regulator and pwm for my panel. > > My panel needs a sequence like > 1. Pull up a gpio line > 2. Maintain some delay > 3. Pull down gpio line > 4. Maintain some delay and > 5. Pull up a gpio line. Yes, I think that kind of thing is exactly what the power sequences bindings/driver are for. But ... > Please find the Image shown in the attachment for better understanding. > > So, to get this done I used your code and created a node like below > and it worked for me. > > backlight { > compatible = "pwm-backlight"; > brightness-levels = <0 16 32 48 64 80 96 112 128 144 160 176 > 192 208 224 240 255>; > default-brightness-level = <12>; > > enable-gpio1 = <&gpx1 5 1 0 0>; > enable-gpio2 = <&gpx3 0 0 0 0>; In your original email, you mentioned that some of those cells for the GPIO control the state features such as pull-up/-down and drive-strength. Those two features should really be configured by pinctrl not by the GPIO bindings, although that's a comment on the GPIO bindings itself, and nothing to do with power sequences.