Subject: [PATCH V2 2/2] ARM: dts: DRA7: Add node for RTC

From: [email-masked] (Keerthy)
Date: Wed, 9 Jul 2014 16:26:03 +0530

On Wednesday 09 July 2014 04:20 PM, Tony Lindgren wrote:
> * Keerthy <[email-masked]> [140709 03:39]:
>> On Wednesday 09 July 2014 03:39 PM, Tony Lindgren wrote:
>>> * Keerthy <[email-masked]> [140709 02:36]:
>>>> On Wednesday 09 July 2014 02:42 PM, Tony Lindgren wrote:
>>>>> * Lokesh Vutla <[email-masked]> [140709 01:37]:
>>>>>> --- a/arch/arm/boot/dts/dra7-evm.dts
>>>>>> +++ b/arch/arm/boot/dts/dra7-evm.dts
>>>>>> @@ -249,6 +249,7 @@
>>>>>>   					regulator-min-microvolt = <1050000>;
>>>>>>   					regulator-max-microvolt = <1050000>;
>>>>>>   					regulator-boot-on;
>>>>>> +					regulator-always-on;
>>>>>>   				};
>>>>> Is this regulator really always on?
>>>> This feeds on to RTC which is a free running clock. So i guess always on is
>>>> justified no?
>>> Well the dts entries should describe the hardware. If the
>>> regulator can be enabled and disabled, we should not claim it's
>>> always on.
>>  From the PMIC perspective every regulator can be enabled and
>> disabled. From a Board perspective there are some which need
>> to be always on. For Ex: SMPS123 which feeds on to the MPU.
> Right, and we already have regulator-boot-on for those. Or are
> you seeing some issue with that?
regulator-boot-on describes that at boot a particular regulator is on.
It does not guarantee that it will be on for the rest of the time. The
regulator framework can go ahead and disable it if no one has requested
for it. In case of RTC we do not want that to happen.

>
>> I guess RTC also needs the supply to be on as long as we want
>> the clock to be ticking.
> Sure, but if somebody wants shut it off regulator-boot-on is
> better from driver point of view.
>
> Regards,
>
> Tony