> -----Original Message----- > From: Ferre, Nicolas > Sent: Friday, May 09, 2014 11:31 PM > To: Yang, Wenyou; Alexandre Belloni > Cc: devicetree@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; > robh+dt@xxxxxxxxxx; broonie@xxxxxxxxxx; linux-arm- > kernel@xxxxxxxxxxxxxxxxxxx > Subject: Re: [PATCH] ARM: dts: at91-sama5d3_xplained: add the regulator > device node > > On 22/04/2014 03:37, Yang, Wenyou : > > Hi, > > > >> -----Original Message----- > >> From: Alexandre Belloni [mailto:alexandre.belloni@xxxxxxxxxxxxxxxxxx] > >> Sent: Monday, April 21, 2014 8:22 PM > >> To: Yang, Wenyou > >> Cc: devicetree@xxxxxxxxxxxxxxx; Ferre, Nicolas; linux- > >> kernel@xxxxxxxxxxxxxxx; robh+dt@xxxxxxxxxx; broonie@xxxxxxxxxx; > >> linux- arm-kernel@xxxxxxxxxxxxxxxxxxx > >> Subject: Re: [PATCH] ARM: dts: at91-sama5d3_xplained: add the > >> regulator device node > >> > >> On 21/04/2014 at 11:54:43 +0200, Alexandre Belloni wrote : > >>> Hi, > >>> > >>> On 21/04/2014 at 12:29:07 +0800, Wenyou Yang wrote : > >>>> + > >>>> + vddana_reg: LDO_REG2 { > >>>> + regulator-name = > "VDDANA"; > >>>> + regulator-min-microvolt > = > >> <3300000>; > >>>> + regulator-max-microvolt > = > >> <3300000>; > >>>> + regulator-always-on; > >>> > >>> I'm pretty sure that one is not always on as you actually have to > >>> configure it to get any voltage. Are you sure you want to set the > >>> regulator-always-on property here ? > >>> > >> > >> Just to clarify my though, wouldn't it be better to make the ADC > >> driver handle that regulator instead of using regulator-always-on ? > > Yes, you are right. > > It should not use regulator-always-on property for this regulator. > > It is ADC driver and ISI driver to handle it(The ISI takes PCK for > clock). > > Hi Wenyou and Alexandre, > > After talking to our system engineers, it not usual to avoid to power > the VDDANA rail. In fact it will prevent you to use all the pads that > are powered by VDDANA: PD20-PD31. Moreover, even if you do not activate > the ADC output on these lines you won't be able to use them as plain > GPIO... (Cf. package and pinout section of the datasheet). > > As the ADVREF pin of the SoC is connected to the VDDANA on this board > (even if this default configuration can be modified with a soldering > iron), we have to note that we may consume a little bit more power. > > But still, I would recommend to keep the "regulator-always-on" property > on this node. Do you agree and allow me to take your first revision of > the patch? I agree. > > > Bye, > -- > Nicolas Ferre Best Regards, Wenyou Yang -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
