Re: [RFC 3/4] PM / devfreq: exynos-bus: add support for suspend OPP

[Tobias Jakobi <tjakobi@math.uni-bielefeld.de>]

Hello Chanwoo,

Chanwoo Choi wrote:
> Hi Tobias,
> 
> On 2016년 11월 23일 22:51, Tobias Jakobi wrote:
>> TODO: write desc
>> Signed-off-by: Tobias Jakobi <tjakobi@math.uni-bielefeld.de>
>> ---
>>  drivers/devfreq/exynos-bus.c | 8 ++++++++
>>  1 file changed, 8 insertions(+)
>>
>> diff --git a/drivers/devfreq/exynos-bus.c b/drivers/devfreq/exynos-bus.c
>> index 29866f7..8a91970 100644
>> --- a/drivers/devfreq/exynos-bus.c
>> +++ b/drivers/devfreq/exynos-bus.c
>> @@ -335,6 +335,7 @@ static int exynos_bus_parse_of(struct device_node *np,
>>  			      struct exynos_bus *bus)
>>  {
>>  	struct device *dev = bus->dev;
>> +	struct dev_pm_opp *suspend_opp;
>>  	unsigned long rate;
>>  	int ret;
>>  
>> @@ -368,6 +369,13 @@ static int exynos_bus_parse_of(struct device_node *np,
>>  		ret = PTR_ERR(bus->curr_opp);
>>  		goto err_opp;
>>  	}
>> +
>> +	suspend_opp = dev_pm_opp_get_suspend_opp(dev);
>> +	if (suspend_opp) {
>> +		bus->devfreq->suspend_freq = dev_pm_opp_get_freq(suspend_opp);
>> +		printk("DEBUG: suspend opp found!\n");
>> +	}
> 
> Looks good to me. But, you have to move this code
> in the exynos_bus_parent_parse_of() because the passive devfreq
> don't need to get the suspend_opp. The suspend_opp is necessary
> only for parent devfreq device.
right, that makes sense!

Thanks again for the review!

- Tobias


> If parent devfreq device change the frequency/voltage,
> the passive devfreq device will change the their frequency/voltage
> according to parent devfreq.
> 
>> +
>>  	rcu_read_unlock();
>>  
>>  	return 0;
>>
>