Re: [PATCH 0/3] mxs-lradc: Add support for current sources

From: Stefan Wahren <stefan.wahren-eS4NqCHxEME@public.gmane.org>
To: Harald Geyer <harald-95f8Dae0BrPYtjvyW6yDsg@public.gmane.org>,
	Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
	devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	linux-iio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
	Shawn Guo <shawnguo-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>,
	Sascha Hauer <kernel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org>
Cc: Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>,
	linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org
Subject: Re: [PATCH 0/3] mxs-lradc: Add support for current sources
Date: Fri, 29 Apr 2016 17:12:53 +0200	[thread overview]
Message-ID: <572379F5.8000501@i2se.com> (raw)
In-Reply-To: <1461333147-11873-1-git-send-email-harald-95f8Dae0BrPYtjvyW6yDsg@public.gmane.org>

Hi Harald,

Am 22.04.2016 um 15:52 schrieb Harald Geyer:
> Patch 1/3 changes the driver and updates the binding documentation
> (I guess it is still in staging.)
>
> Patches 2/3 and 3/3 add the devicetree nodes to imx23 and imx28 boards.
> I'd like to get input whether this is actually desired. On boards where
> these regulators would never be enabled this costs a few extra bytes of
> RAM for allocation of the device data, because the nodes can't be easily
> removed in .dts files which are including the .dtsi files. The alternative
> is to add the new nodes to many .dts files, which would be a lot code
> duplication.

if i get it right the real intention of this patch series is to make the
mxs-lradc provide resistance values instead of voltages. So how about
dropping the whole regulator stuff and provide the values as
IIO_RESISTANCE via iio interface?

Btw this feature should be only added to dts files where is actually used.

Regards
Stefan

>
> Harald Geyer (3):
>   iio: mxs-lradc: Add regulators for current sources
>   ARM: dts: imx23: Provide regulators for the current sources of the
>     LRADC
>   ARM: dts: imx28: Provide regulators for the current sources of the
>     LRADC
>
>  .../bindings/staging/iio/adc/mxs-lradc.txt         |  29 ++++
>  arch/arm/boot/dts/imx23.dtsi                       |   8 ++
>  arch/arm/boot/dts/imx28.dtsi                       |   8 ++
>  drivers/iio/adc/Kconfig                            |   1 +
>  drivers/iio/adc/mxs-lradc.c                        | 152 +++++++++++++++++++++
>  5 files changed, 198 insertions(+)
>