From mboxrd@z Thu Jan 1 00:00:00 1970 From: Laxman Dewangan Subject: Re: [PATCH V2 1/2] regulator: pwm: DT: Add ramp delay for exponential voltage transition Date: Tue, 22 Nov 2016 14:20:20 +0530 Message-ID: <583406CC.9080306@nvidia.com> References: <1479479756-10755-1-git-send-email-ldewangan@nvidia.com> <20161121161727.y6pvydowiyeyy7qs@rob-hp-laptop> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20161121161727.y6pvydowiyeyy7qs@rob-hp-laptop> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Rob Herring Cc: broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, mark.rutland-5wv7dgnIgG8@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Douglas Anderson , Aleksandr Frid List-Id: devicetree@vger.kernel.org On Monday 21 November 2016 09:47 PM, Rob Herring wrote: > On Fri, Nov 18, 2016 at 08:05:55PM +0530, Laxman Dewangan wrote: >> Some PWM regulator has the exponential transition in voltage change as >> opposite to fixed slew-rate linear transition on other regulators. >> For such PWM regulators, add the property to tell that voltage change >> is exponential and having fixed delay for any level of change. >> >> Signed-off-by: Laxman Dewangan >> CC: Douglas Anderson >> CC: Aleksandr Frid >> >> --- >> This patch is continuation of discussion on patch >> regulator: pwm: Fix regulator ramp delay for continuous mode >> https://patchwork.kernel.org/patch/9216857/ >> where is it discussed to have separate property for PWM which has >> exponential voltage transition. >> >> Changes from V1: >> - Pass the flag to tell that voltage ramp is exponential instead of >> providing delay. >> --- >> .../devicetree/bindings/regulator/pwm-regulator.txt | 12 ++++++++++++ >> 1 file changed, 12 insertions(+) >> >> diff --git a/Documentation/devicetree/bindings/regulator/pwm-regulator.txt b/Documentation/devicetree/bindings/regulator/pwm-regulator.txt >> index 3aeba9f..2d9ef3a 100644 >> --- a/Documentation/devicetree/bindings/regulator/pwm-regulator.txt >> +++ b/Documentation/devicetree/bindings/regulator/pwm-regulator.txt >> @@ -54,6 +54,18 @@ Optional properties: >> -------------------- >> - enable-gpios: GPIO to use to enable/disable the regulator >> >> +- voltage-ramp-exponential: Boolean, Some of PWM regulator has the exponential >> + transition in voltage ramp as opposite to fixed >> + slew-rate linear transition on other regulators. >> + For such PWM regulator, presence of this property will >> + tell that value of the regulator ramp delay provided by >> + DT property "regulator-ramp-delay" is exponential and >> + fixed delay for any voltage level change. >> + If PWM regulator supports the fixed linear slew rate >> + then this property should be absent from DT node and >> + property "regulator-ramp-delay" is used as linear slew >> + rate. > Sorry, but on further thought, I don't think we should mix different > units for the same property. Also, the fact that the ramp is exponential > is irrelevant. You just want an absolute delay time rather than a rate, > right? So instead, how about just "regulator-ramp-time-us". Roughly what > you had in v1, but not PWM specific. Can we say "regulator-settling-time-us" and make it generic i.e. part of the regulator core instead of PWM regulator specific? So no change for "regulator-ramp-delay". new property "regulator-settling-time-us" for fixed settling time in any voltage level change. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html