On Sat, Apr 10, 2021 at 7:12 PM Alexandru Ardelean
<ardeleanalex@xxxxxxxxx> wrote:
>
> On Fri, Apr 9, 2021 at 9:51 PM Lucas Stankus <lucas.p.stankus@xxxxxxxxx> wrote:
> >
> > Ditch platform_data fields in favor of device tree properties for
> > configuring EXCA and EXCB output.
> > This also removes the fields from the platform_data struct, since they're
> > not used anymore.
> >
> > Signed-off-by: Lucas Stankus <lucas.p.stankus@xxxxxxxxx>
> > ---
> > drivers/staging/iio/cdc/ad7746.c | 33 +++++++++++++++++---------------
> > drivers/staging/iio/cdc/ad7746.h | 4 ----
> > 2 files changed, 18 insertions(+), 19 deletions(-)
> >
> > diff --git a/drivers/staging/iio/cdc/ad7746.c b/drivers/staging/iio/cdc/ad7746.c
> > index dfd71e99e872..63041b164dbe 100644
> > --- a/drivers/staging/iio/cdc/ad7746.c
> > +++ b/drivers/staging/iio/cdc/ad7746.c
> > @@ -677,8 +677,10 @@ static int ad7746_probe(struct i2c_client *client,
> > const struct i2c_device_id *id)
> > {
> > struct ad7746_platform_data *pdata = client->dev.platform_data;
> > + struct device_node *np = client->dev.of_node;
> > struct ad7746_chip_info *chip;
> > struct iio_dev *indio_dev;
> > + unsigned int exca_en, excb_en;
> > unsigned char regval = 0;
> > int ret = 0;
> >
> > @@ -703,26 +705,27 @@ static int ad7746_probe(struct i2c_client *client,
> > indio_dev->num_channels = ARRAY_SIZE(ad7746_channels);
> > indio_dev->modes = INDIO_DIRECT_MODE;
> >
>
> [1]
>
> > - if (pdata) {
> > - if (pdata->exca_en) {
> > - if (pdata->exca_inv_en)
> > - regval |= AD7746_EXCSETUP_NEXCA;
> > - else
> > - regval |= AD7746_EXCSETUP_EXCA;
> > - }
> > + ret = of_property_read_u32(np, "adi,exca-output", &exca_en);
>
> maybe a better idea would be to use:
>
> device_property_read_u32(dev, .... )
> where:
> dev = client->dev.;
>
> this would make the driver a bit more friendly with both OF and ACPI
>
> > + if (!ret && exca_en) {
> > + if (exca_en == 1)
> > + regval |= AD7746_EXCSETUP_EXCA;
> > + else
> > + regval |= AD7746_EXCSETUP_NEXCA;
> > + }
> >
> > - if (pdata->excb_en) {
> > - if (pdata->excb_inv_en)
> > - regval |= AD7746_EXCSETUP_NEXCB;
> > - else
> > - regval |= AD7746_EXCSETUP_EXCB;
> > - }
> > + ret = of_property_read_u32(np, "adi,excb-output", &excb_en);
> > + if (!ret && excb_en) {
> > + if (excb_en == 1)
> > + regval |= AD7746_EXCSETUP_EXCB;
> > + else
> > + regval |= AD7746_EXCSETUP_NEXCB;
> > + }
> >
> > + if (pdata) {
> > regval |= AD7746_EXCSETUP_EXCLVL(pdata->exclvl);
> > } else {
> > dev_warn(&client->dev, "No platform data? using default\n");
> > - regval = AD7746_EXCSETUP_EXCA | AD7746_EXCSETUP_EXCB |
> > - AD7746_EXCSETUP_EXCLVL(3);
>
> This logic is problematic now.
> Because no matter what you're setting in the DT, it always gets
> overridden here because there is no platform data.
>
> Maybe a better idea is to do something like:
> if (!pdata)
> regval = AD7746_EXCSETUP_EXCLVL(3);
>
> but this should be placed somewhere around [1]
[ i can see that this logic will get corrected in the next patch]
to add here a bit: the idea of a patch is that it should try to not
introduce any [even temporary] breakage, even when it's in a series;
if a driver was already broken, then it should get fixed via it's own patch;
but no patch should introduce any breakages [if possible]
>
>
> > + regval = AD7746_EXCSETUP_EXCLVL(3);
> > }
> >
> > ret = i2c_smbus_write_byte_data(chip->client,
> > diff --git a/drivers/staging/iio/cdc/ad7746.h b/drivers/staging/iio/cdc/ad7746.h
> > index 8bdbd732dbbd..6cae4ecf779e 100644
> > --- a/drivers/staging/iio/cdc/ad7746.h
> > +++ b/drivers/staging/iio/cdc/ad7746.h
> > @@ -19,10 +19,6 @@
> >
> > struct ad7746_platform_data {
> > unsigned char exclvl; /*Excitation Voltage Level */
> > - bool exca_en; /* enables EXCA pin as the excitation output */
> > - bool exca_inv_en; /* enables /EXCA pin as the excitation output */
> > - bool excb_en; /* enables EXCB pin as the excitation output */
> > - bool excb_inv_en; /* enables /EXCB pin as the excitation output */
> > };
> >
> > #endif /* IIO_CDC_AD7746_H_ */
> > --
> > 2.31.1
> >
