Re: [PATCH v6 1/4] mfd: mxs-lradc: Add support for mxs-lradc MFD

From: Lee Jones
Date: Thu Sep 29 2016 - 19:12:33 EST


On Thu, 29 Sep 2016, Stefan Wahren wrote:

> Hi Lee,
>
> [add Rob and Mark]
>
> > Lee Jones <lee.jones@xxxxxxxxxx> hat am 29. September 2016 um 19:15
> > geschrieben:
> >
> >
> > On Thu, 29 Sep 2016, Stefan Wahren wrote:
> > > > Lee Jones <lee.jones@xxxxxxxxxx> hat am 28. September 2016 um 03:05
> > > > geschrieben:
> > > >
> > > >
> > > > On Sat, 17 Sep 2016, Ksenija Stanojevic wrote:
> > > >
> > > > > +
> > > > > +static int mxs_lradc_probe(struct platform_device *pdev)
> > > > > +{
> > > > > + const struct of_device_id *of_id;
> > > > > + struct device *dev = &pdev->dev;
> > > > > + struct device_node *node = dev->of_node;
> > > > > + struct mxs_lradc *lradc;
> > > > > + struct mfd_cell *cells = NULL;
> > > > > + int ret = 0;
> > > > > + u32 ts_wires = 0;
> > > > > +
> > > > > + lradc = devm_kzalloc(&pdev->dev, sizeof(*lradc), GFP_KERNEL);
> > > > > + if (!lradc)
> > > > > + return -ENOMEM;
> > > > > +
> > > > > + of_id = of_match_device(mxs_lradc_dt_ids, &pdev->dev);
> > > > > + lradc->soc = (enum mxs_lradc_id)of_id->data;
> > > > > +
> > > > > + lradc->clk = devm_clk_get(&pdev->dev, NULL);
> > > > > + if (IS_ERR(lradc->clk)) {
> > > > > + dev_err(dev, "Failed to get the delay unit clock\n");
> > > > > + return PTR_ERR(lradc->clk);
> > > > > + }
> > > > > +
> > > > > + ret = clk_prepare_enable(lradc->clk);
> > > > > + if (ret) {
> > > > > + dev_err(dev, "Failed to enable the delay unit clock\n");
> > > > > + return ret;
> > > > > + }
> > > > > +
> > > > > + ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires",
> > > >
> > > > Have you moved the documentation into devicetree/bindings/mfd?
> > > >
> > >
> > > i hope it's okay if i answer. The binding has moved to
> > > devicetree/binding/iio/adc/ [1]
> > >
> > > Should it move completely to mfd or split too?
> > >
> > > I'm asking myself how we keep DT ABI in the latter case.
> > >
> > > [1] -
> > > http://lxr.free-electrons.com/source/Documentation/devicetree/bindings/iio/adc/mxs-lradc.txt
> >
> > I haven't read into the documentation too to deeply, but it stands to
> > reason that the bindings which are now being used in MFD should be
> > documented in the MFD binding document, and the ones which are no longer
> > used in the IIO driver should be removed.
>
> sure, that isn't a problem.
>
> The more interesting question would be: do we need a new compatible string for
> the mfd driver?

No, I don't think that is necessary.

> In that case the ADC won't probe for the combination of old devicetree blobs and
> new kernel.


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