Re: [PATCH v5 3/4] iio: trigger: Introduce IIO hrtimer based trigger

[Daniel Baluta]

On Thu, May 7, 2015 at 12:19 PM, Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
> On 06/05/15 18:37, Daniel Baluta wrote:
>> On Wed, May 6, 2015 at 8:16 PM, Jonathan Cameron <jic23@xxxxxxxxxx> wrote:
>>> On 06/05/15 17:25, Daniel Baluta wrote:
>>>>
>>>>
>>>> On 05/05/2015 04:51 PM, Jonathan Cameron wrote:
>>>>>
>>>>>
>>>>> On 4 May 2015 20:54:08 GMT+01:00, Lars-Peter Clausen <lars@xxxxxxxxxx> wrote:
>>>>>> On 05/04/2015 12:50 PM, Daniel Baluta wrote:
>>>>>> [...]
>>>>>>> +IIO_HRTIMER_INFO_ATTR(sampling_frequency, S_IRUGO | S_IWUSR,
>>>>>>> +              iio_hrtimer_info_show_sampling_frequency,
>>>>>>> +              iio_hrtimer_info_store_sampling_frequency);
>>>>>>
>>>>>> I wonder if the sampling frequency should be configurable the regular
>>>>>> IIO
>>>>>> API, just like any other IIO device. But things like min/max sampling
>>>>>> frequency should be configured in configfs.
>>>>> Would have to be in the trigger dir rather than device... Makes sense to put it there.
>>>>> Limits on it here seem like a sensible idea.
>>>>
>>>> But then each trigger will have sampling_frequency right? This is not what we want.
>>> I'm confused now.  Why not?  Each hrtimer trigger created in configfs should have
>>> it's own sampling frequency should it not?
>>
>> I was referring to triggers in general, not just hrtimer triggers.
>>
>> But I see now that we can set trig->dev.groups to point to our
>> specific attributes. This
>> should work.
>>
>> Anyhow, I'm not convinced that sampling_frequency should be configured
>> from sysfs.
>> We create the trigger from configfs:
>>
>> $ mkdir /config/triggers/hrtimer-instance0
>>
>> Then, likely we have to do something like this:
>>
>> $ echo 100 > /sys/bus/iio/trigger7/sampling_frequency
>>
>> How is the user application going to know which is the exact directory
>> for hrtimer-instance0 ?
>>
>> Daniel.
>>
> Find it by name like we normally do?

Ok :). I will move this to sysfs and send v6.

thanks,
Daniel.
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