Re: [PATCH v3 3/3] iio: adc: add ADC driver for the TI TSC2046 controller

From: Jonathan Cameron
Date: Mon Mar 29 2021 - 06:24:32 EST


On Mon, 29 Mar 2021 09:38:38 +0200
Oleksij Rempel <o.rempel@xxxxxxxxxxxxxx> wrote:

> On Mon, Mar 22, 2021 at 02:27:22PM +0000, Jonathan Cameron wrote:
> > > > > +static DECLARE_TI_TSC2046_8_CHANNELS(tsc2046_adc, 12);
> > > > > +
> > > > > +static const struct tsc2046_adc_dcfg tsc2046_adc_dcfg_tsc2046e = {
> > > > > + .channels = tsc2046_adc_channels,
> > > > > + .num_channels = ARRAY_SIZE(tsc2046_adc_channels),
> > > > > +};
> > > > > +
> > > >
> > > > Hmm. Flexibility that isn't yet used. Normally I'm pretty resistant
> > > > to this going in, unless I'm reassured that there is support for additional
> > > > devices already in the pipeline. Is that true here? Otherwise
> > > > this is basically unneeded complexity.
> > >
> > > In the long term this driver should replace
> > > drivers/input/touchscreen/ads7846.c
> > >
> > > This driver supports ti,ads7843, ti,ads7845, ti,ads7846.. at least with
> > > following number of supported channels:
> > > ti,ads7843 - 4 channels: x, y, aux0, aux1
> > > ti,ads7845 - 3 channels: x, y, aux0
> > > ti,ads7846 - 8 channels...
> > >
> > > Currently I don't have this HW for testing and there a subtle
> > > differences that have to be taken care of and tested.
> > >
> >
> > Note that I'm only going to merge this driver with an explicit statement
> > from Dmitry as input maintainer that he is fine with this approach.
>
> Since there is still no Dmitry's feedback please take a look to the
> ti,ads7843 datasheet:
> https://www.ti.com/lit/ds/symlink/ads7843.pdf
>
> On the page 1 you can see, that this device has two general purpose ADC
> inputs IN3, IN4. If some one will decide to mainline support for this
> pins, will end with IIO ADC driver any way :)

Understood, but I'm still going to want Dmitry to give an opinion on
this. That might take a little while though as he may well be busy!

Jonathan

>
> Regards,
> Oleksij