linux-kernel - Re: [PATCH] rtc: pcf8563: disable CLKOUT

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Message-ID: <561DD7D1.5040102@denx.de>
Date:	Wed, 14 Oct 2015 06:19:29 +0200
From:	Heiko Schocher <hs@...x.de>
To:	Alexandre Belloni <alexandre.belloni@...e-electrons.com>
Cc:	linux-kernel@...r.kernel.org, Georg.Soffel@...ch-si.com,
	rtc-linux@...glegroups.com,
	Alessandro Zummo <a.zummo@...ertech.it>,
	devicetree@...r.kernel.org
Subject: Re: [PATCH] rtc: pcf8563: disable CLKOUT

Hello Alexandre,

Am 13.10.2015 um 22:17 schrieb Alexandre Belloni:
> Hi,
>
> On 13/10/2015 at 07:08:58 +0200, Heiko Schocher wrote :
>> Disable the CLKOUT of the RTC after power-up.
>> After power-up/reset of the RTC, CLKOUT is enabled by default,
>> with CLKOUT enabled the RTC chip has 2-3 times higher power
>> consumption. If you do not need CLKOUT, you can disable the
>> CLKOUT with setting "disable-clkout" property.
>>
>
> I think you can simply unconditionally disable clkout. My preferred way
> of doing what you suggest is probably to register a clock in the CCF. If
> the clock is not used, it will be automatically disabled.
> It will also provide a generic way of setting the clkout frequency (some
> RTC are able to output 32kHZ, 1kHz and 1Hz).

Does disabling it ot break some boards?

I take a look into CCF, good idea.

bye,
Heiko
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