Re: [PATCH v2 3/4] mfd: add support for Allwinner SoCs ADC

[Lee Jones]

On Mon, 18 Jul 2016, Jonathan Cameron wrote:

> On 15/07/16 10:59, Quentin Schulz wrote:
> > The Allwinner SoCs all have an ADC that can also act as a touchscreen
> > controller and a thermal sensor. For now, only the ADC and the thermal
> > sensor drivers are probed by the MFD, the touchscreen controller support
> > will be added later.
> > 
> > Signed-off-by: Quentin Schulz <quentin.schulz@xxxxxxxxxxxxxxxxxx>
> Hmm. Previous patch includes the header this one creates.  Ordering issue?
> The depends kind of prevents build failures by ensuring that can't be built
> until this one is in place, but it is certainly an ugly way to do it.
> 
> Few little bits innline.
> > ---
> > 
> > v2:
> >  - add license headers,
> >  - reorder alphabetically includes,
> >  - add SUNXI_GPADC_ prefixes for defines,
> > 
> >  drivers/mfd/Kconfig                 |  14 +++
> >  drivers/mfd/Makefile                |   2 +
> >  drivers/mfd/sunxi-gpadc-mfd.c       | 197 ++++++++++++++++++++++++++++++++++++
> >  include/linux/mfd/sunxi-gpadc-mfd.h |  23 +++++
> >  4 files changed, 236 insertions(+)
> >  create mode 100644 drivers/mfd/sunxi-gpadc-mfd.c
> >  create mode 100644 include/linux/mfd/sunxi-gpadc-mfd.h

[...]

> > +static struct mfd_cell sun6i_gpadc_mfd_cells[] = {
> > +	{
> > +		.name	= "sun6i-a31-gpadc-iio",
> > +		.resources = adc_resources,
> > +		.num_resources = ARRAY_SIZE(adc_resources),
> > +	}, {
> > +		.name = "iio_hwmon",
> I still really dislike using this to force the probe of that driver but
> kind of up to the hwmon / mfd guys on this.

Can you at least say *why* you don't like it?

How else would it get probed?

> I don't have any better suggestions though..
> > +	},
> > +};

[...]

> > +	if (ret) {
> > +		dev_err(&pdev->dev, "failed to add MFD devices: %d\n", ret);
> > +		regmap_del_irq_chip(irq, sunxi_gpadc_mfd_dev->regmap_irqc);
> > +		return ret;
> > +	}
> > +
> > +	dev_info(&pdev->dev, "successfully loaded\n");
> Seems like noise to me, but not my subsystem :)

Agreed, I don't allow this either.

[...]

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org â Open source software for ARM SoCs
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