Re: [PATCHv5] support for AD5820 camera auto-focus coil

From: Pavel Machek
Date: Thu Jun 02 2016 - 15:27:47 EST


On Thu 2016-06-02 10:45:45, Sakari Ailus wrote:
> On Thu, Jun 02, 2016 at 12:08:40AM +0200, Pavel Machek wrote:
> > On Wed 2016-06-01 18:24:39, Sakari Ailus wrote:
> > > Hi Pavel,
> >
> > > > Well, it does not use any dt properties. So there's not really much to
> > > > discuss with dt people...
> > > >
> > > > Maybe "ad5820" needs to go to list of simple i2c drivers somewhere,
> > > > but...
> > >
> > > It's an I2C device and it does use a regulator. Not a lot, though, these are
> > > both quite basic stuff. This should still be documented as the people who
> > > write the DT bindings (in general) aren't expected to read driver code as
> > > well. That's at least my understanding.
> >
> > Yep, you are right, I forgot about the regulator. Something like this?
> >
> > Thanks,
> > Pavel
> >
> > diff --git a/Documentation/devicetree/bindings/media/i2c/ad5820.txt b/Documentation/devicetree/bindings/media/i2c/ad5820.txt
> > new file mode 100644
> > index 0000000..87c98f1
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/media/i2c/ad5820.txt
>
> I might use the compatible string as such as a part of the file name. Up to
> you.

Sorry, can't do that, for consistency with other ad* files in the directory.

> > @@ -0,0 +1,20 @@
> > +* Analog Devices AD5820 autofocus coil
> > +
> > +Required Properties:
> > +
> > + - compatible: Must contain "adi,ad5820"
> > +
> > + - reg: I2C slave address
> > +
> > + - VANA-supply: supply of voltage for VANA pin
> > +
> > +Example:
> > +
> > + /* D/A converter for auto-focus */
>
> There is definitely D/A conversion happening there but I'm not sure I'd
> characterise the device as such. They're typically called "voice coil
> drivers", perhaps because the devices are similar to a parts of a
> loudspeaker.

Well, I'm pretty sure I did not invent that comment, but I can drop
it.

Best regards,
Pavel
--
(english) http://www.livejournal.com/~pavelmachek
(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html