From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jon Hunter Subject: Re: [PATCH V3 3/4] pwm: tegra: Add DT binding details to configure pin in suspends/resume Date: Fri, 7 Apr 2017 08:49:08 +0100 Message-ID: References: <1491488461-24621-1-git-send-email-ldewangan@nvidia.com> <1491488461-24621-4-git-send-email-ldewangan@nvidia.com> <58E67152.1080400@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <58E67152.1080400-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Laxman Dewangan , thierry.reding-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org Cc: mark.rutland-5wv7dgnIgG8@public.gmane.org, linux-pwm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org On 06/04/17 17:48, Laxman Dewangan wrote: > > On Thursday 06 April 2017 08:56 PM, Jon Hunter wrote: >> On 06/04/17 15:21, Laxman Dewangan wrote: >>> In some of NVIDIA Tegra's platform, PWM controller is used to >>> control the PWM controlled regulators. PWM signal is connected to >>> the VID pin of the regulator where duty cycle of PWM signal decide >>> the voltage level of the regulator output. >>> >>> The tristate (high impedance of PWM pin form Tegra) also define >> s/form/from/ >> s/define/defines/ >> >>> one of the state of PWM regulator which needs to be configure in >>> suspend state of system. >> It maybe clearer to say that when the system enters suspend the >> regulator requires the pwm output to be tristated. > > Not necessarily that every PWM regulator interfaces needs it. It > depends on the devices. Yes I understand that. I am just saying the description could be a little clearer. > So I will say: > > When system enters suspend, in some of PWM regulator interface, it is > required to to set the PWM output to be tristated. Ok, but I think you should say why that is, because from the above sentence alone it is not clear. Maybe you should say that some PWM client/slave devices require the PWM output to be tristated. Jon -- nvpublic