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Re: [PATCH v4 3/8] clk: add support for clocks provided by SCP(System Control Processor)

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On 03/07/15 15:52, Sudeep Holla wrote:

[...]

>>> +static int scpi_clk_set_rate(struct clk_hw *hw, unsigned long rate,
>>> +			     unsigned long parent_rate)
>>> +{
>>> +	struct scpi_clk *clk = to_scpi_clk(hw);
>>> +
>>> +	return clk->scpi_ops->clk_set_val(clk->id, rate);
>>> +}
>>> +
>>> +static void scpi_clk_disable(struct clk_hw *hw)
>>> +{
>>> +	scpi_clk_set_rate(hw, 0, 0);
>>
>> Does this mean you have to set a rate to enable the clock? Are
>> you relying on drivers to call clk_set_rate() to implicitly
>> enable the clock? If so, it would be better to cache the rate of
>> the clock in set_rate if the clock isn't enabled in software and
>> then send the cached rate during enable.
>>
>
> Agreed, I have asked the firmware/SCPI specification guys about
> more details on what to expect from firmware. Once they get back,
> will update the code considering your feedback.
>

OK, I got feedback and looks like it was never planned to implement that
and even specification needs to be fixed. So I will drop the disable
callback support. For now, we don't support {en,dis}able
features. We need to amend the specification to fix that.

Regards,
Sudeep
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Re: [PATCH v4 3/8] clk: add support for clocks provided by SCP(System  Control Processor) Sudeep Holla <sudeep.holla@arm.com> - 2015-07-03 17:00 +0200
  Re: [PATCH v4 3/8] clk: add support for clocks provided by SCP(System  Control Processor) Sudeep Holla <sudeep.holla@arm.com> - 2015-07-03 18:20 +0200

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