Re: [PATCH v2 2/7] iio: adc: max1027: Make it optional to use interrupts

From: Jonathan Cameron
Date: Mon Oct 07 2019 - 07:45:00 EST


On Mon, 7 Oct 2019 12:01:22 +0200
Miquel Raynal <miquel.raynal@xxxxxxxxxxx> wrote:

> Hi Jonathan,
>
> Jonathan Cameron <jic23@xxxxxxxxxx> wrote on Sun, 6 Oct 2019 11:18:37
> +0100:
>
> > On Thu, 3 Oct 2019 19:33:56 +0200
> > Miquel Raynal <miquel.raynal@xxxxxxxxxxx> wrote:
> >
> > > The chip has a 'start conversion' and a 'end of conversion' pair of
> > > pins. They can be used but this is absolutely not mandatory as regular
> > > polling of the value is totally fine with the current internal
> > > clocking setup. Turn the interrupts optional and do not error out if
> > > they are not inquired in the device tree. This has the effect to
> > > prevent triggered buffers use though.
> > >
> > > Signed-off-by: Miquel Raynal <miquel.raynal@xxxxxxxxxxx>
> >
> > Hmm. I haven't looked a this in a great deal of depth but if we support
> > single channel reads it should be possible to allow the use of a
> > trigger from elsewhere. Looks like a fair bit of new code would be needed
> > to support that though. So perhaps this is a good first step.
> >
> > It's a bit annoying that the hardware doesn't provide a EOC bit
> > anywhere in the registers. That would have allowed us to be a bit
> > cleverer.
>
> I totally agree. Actually, this chip does not support any 'register
> read', the only things we can read are measures (temperature/voltages).

Ah. Good point. Shall we polled reading of channels which is what
I meant ;)

Jonathan

>
>
> Thanks,
> Miquèl