linux-kernel - Re: [PATCH 1/2] regulators: Add definition of regulator_set_voltage_time() for !CONFIG

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Message-ID: <CAKohpo=vPojhX_9u6Coa=2Kiu0jY9hCTg2B0WiWfJS8ZQxK4Rg@mail.gmail.com>
Date:	Mon, 2 Jun 2014 18:44:35 +0530
From:	Viresh Kumar <viresh.kumar@...aro.org>
To:	Mark Brown <broonie@...nel.org>
Cc:	"Rafael J. Wysocki" <rjw@...ysocki.net>,
	Lists linaro-kernel <linaro-kernel@...ts.linaro.org>,
	"linux-pm@...r.kernel.org" <linux-pm@...r.kernel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Arvind Chauhan <arvind.chauhan@....com>,
	Eduardo Valentin <edubezval@...il.com>,
	Pavel Machek <pavel@....cz>,
	Liam Girdwood <lgirdwood@...il.com>
Subject: Re: [PATCH 1/2] regulators: Add definition of regulator_set_voltage_time()
 for !CONFIG_REGULATOR

On 2 June 2014 17:53, Mark Brown <broonie@...nel.org> wrote:
> If the consumer tried to set a voltage presumably it cares if that
> voltage was set - for example if your cpufreq driver tries to increase
> the voltage of a core supply so that it can then raise the frequency the
> user is going to be upset if the voltage was not actually raised and it
> goes off and raises the clock rate causing the system to become unstable.

If the driver continued despite getting regulator as NULL, it means that
regulator isn't a MUST for it. For example a CPUFreq driver may work
with or without a regulator.

Now if the dummy calls return *error* for some cases then these driver
will have to do
if(xyz)
    API-call()..

And so dummy APIs like clk_set_rate(), clk_get_rate(),
regulator_set_voltage() must return zero..

To get rid of this in drivers these dummy routines *must* behave as
they passed, if the drivers really care about them then they must
quit as soon as regulator_get() returned NULL.

This is why we have such implementations in clk framework which are
very well thought earlier.

Does this make sense?
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