Ahoy!

On Tue, Sep 12, 2017 at 01:40:51PM +0200, Pavel Machek wrote:

Hi!

quoted

On Tue, Sep 12, 2017 at 12:36:28PM +0200, Pavel Machek wrote:

quoted

Hi!

There were some changes to as3645a flash controller. Before we have
stable interface we have to keep forever I want to ask:

What directory are the flash controls in?

/sys/class/leds/led-controller:flash ?

Could we arrange for something less generic, like

/sys/class/leds/main-camera:flash ?

Thanks,

The LEDs are called as3645a:flash and as3645a:indicator currently, based on
the name of the LED controller's device node. There are no patches related
to this set though; these have already been merged.

The label should be a "human readable string describing the device" (from
ePAPR, please excuse me for not having a newer spec), and the led common
bindings define it as:

- label : The label for this LED. If omitted, the label is taken from the node
          name (excluding the unit address). It has to uniquely identify
          a device, i.e. no other LED class device can be assigned the same
          label.

Ok, can we set the label to "main_camera" for N9 and n950 cases?

"as3645a:flash" is really wrong name for a LED. Information that
as3645 is already present elsewhere in /sys. Information where the LED
is and what it does is not.

I'd like to have torch application that just writes
/sys/class/leds/main_camera:white:flash/brightness . It should not
need to know hardware details of differnet phones.

Hmm. There don't seem to be a uniform way to form labels.

What I'd do is to look up a LED that implements LED flash class and use
that; it's a flash LED and is likely to be the most powerful in the system.
There could be several as well, some more recent flash controllers have
more than one.

I wonder what Jacek thinks.

quoted

I don't think that you should be looking to use this to associate it with
the camera as such. The association information with the sensor is
available to the kernel but there's no interface that could meaningfully
expose it to the user right now.

Yeah, I'm not looking for sensor association. I'm looking for
reasonable userland interface.

Ack. Hopefully we can provide the association some day, too...

-- 
Kind regards,

Sakari Ailus
e-mail: sakari.ailus@iki.fi