From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from perceval.ideasonboard.com ([213.167.242.64]:36144 "EHLO perceval.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387985AbeIUBtn (ORCPT ); Thu, 20 Sep 2018 21:49:43 -0400 From: Laurent Pinchart To: Ricardo Ribalda Delgado Cc: Pavel Machek , Sakari Ailus , Mauro Carvalho Chehab , linux-media , LKML , Hans Verkuil Subject: Re: [PATCH v2 2/4] [media] ad5820: Add support for enable pin Date: Thu, 20 Sep 2018 23:04:46 +0300 Message-ID: <6867138.NTEK45P8Ux@avalon> In-Reply-To: <1887575.If169ivQRG@avalon> References: <20180920161912.17063-2-ricardo.ribalda@gmail.com> <1887575.If169ivQRG@avalon> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Sender: linux-media-owner@vger.kernel.org List-ID: On Thursday, 20 September 2018 23:04:21 EEST Laurent Pinchart wrote: > Hi Ricardo, > > On Thursday, 20 September 2018 22:12:44 EEST Ricardo Ribalda Delgado wrote: > > On Thu, Sep 20, 2018 at 9:08 PM Pavel Machek wrote: > > > On Thu 2018-09-20 21:06:16, Ricardo Ribalda Delgado wrote: > > >> On Thu, Sep 20, 2018 at 8:54 PM Pavel Machek wrote: > > >>> On Thu 2018-09-20 20:45:52, Ricardo Ribalda Delgado wrote: > > >>>> This patch adds support for a programmable enable pin. It can be > > >>>> used in situations where the ANA-vcc is not configurable (dummy- > > >>>> regulator), or just to have a more fine control of the power saving. > > >>>> > > >>>> The use of the enable pin is optional. > > >>>> > > >>>> Signed-off-by: Ricardo Ribalda Delgado > > >>> > > >>> Do we really want to do that? > > >>> > > >>> Would it make more sense to add gpio-regulator and connect ad5820 to > > >>> it in such case? > > >> > > >> My board (based on db820c) has both: > > >> > > >> ad5820: dac@0c { > > >> > > >> compatible = "adi,ad5820"; > > >> reg = <0x0c>; > > >> > > >> VANA-supply = <&pm8994_l23>; > > >> enable-gpios = <&msmgpio 26 GPIO_ACTIVE_HIGH>; > > >> > > >> }; > > > > > > Well, I'm sure you could have gpio-based regulator powered from > > > pm8994_l23, and outputting to ad5820. > > > > > > Does ad5820 chip have a gpio input for enable? > > > > xshutdown pin: > > http://www.analog.com/media/en/technical-documentation/data-sheets/AD5821. > > pd f > > > > (AD5820,AD5821, and AD5823 are compatibles, or at least that is waht > > the module manufacturer says :) > > Is that the pin that msmgpio 26 is connected to on your board ? > > I'd argue that the GPIO should be called xshutdown in that case, as DT > usually uses the pin name, but there's precedent of using well-known names > for pins with the same functionality. In any case you should update the DT > bindings to document the new property, and clearly explain that it > describes the GPIO connected to the xshutdown pin. Please CC the > devicetree@vger.kernel.org mailing list on the bindings change (they > usually like bindings changes to be split to a separate patch). And now I've noticed patch 3/4 :-/ Please scratch this. -- Regards, Laurent Pinchart