On Fri, 1 Mar 2019 07:17:04 +0000
"Ardelean, Alexandru" <Alex.Ardelean@xxxxxxxxxx> wrote:
> On Thu, 2019-02-28 at 11:24 -0300, Renato Lui Geh wrote:
> >
> >
> > The AD7780 driver contains status pattern bits designed for checking
> > whether serial transfers have been correctly performed. Pattern macros
> > were previously generated through bit fields. This patch sets good
> > pattern values directly and masks through GENMASK.
> >
> > Signed-off-by: Renato Lui Geh <renatogeh@xxxxxxxxx>
> > ---
> > drivers/staging/iio/adc/ad7780.c | 20 +++++++++-----------
> > 1 file changed, 9 insertions(+), 11 deletions(-)
> >
> > diff --git a/drivers/staging/iio/adc/ad7780.c
> > b/drivers/staging/iio/adc/ad7780.c
> > index 7a68e90ddf14..56c49e28f432 100644
> > --- a/drivers/staging/iio/adc/ad7780.c
> > +++ b/drivers/staging/iio/adc/ad7780.c
> > @@ -17,6 +17,7 @@
> > #include <linux/sched.h>
> > #include <linux/gpio/consumer.h>
> > #include <linux/module.h>
> > +#include <linux/bits.h>
> >
> > #include <linux/iio/iio.h>
> > #include <linux/iio/sysfs.h>
> > @@ -28,16 +29,13 @@
> > #define AD7780_ID1 BIT(4)
> > #define AD7780_ID0 BIT(3)
> > #define AD7780_GAIN BIT(2)
> > -#define AD7780_PAT1 BIT(1)
> > -#define AD7780_PAT0 BIT(0)
>
> I don't see a problem to leave the bitfields; they can be read & matched
> easier with the datasheet.
>
> >
> > -#define AD7780_PATTERN (AD7780_PAT0)
> > -#define AD7780_PATTERN_MASK (AD7780_PAT0 | AD7780_PAT1)
> >
> > -#define AD7170_PAT2 BIT(2)
>
> > +#define AD7780_PATTERN_GOOD 1
>
> It was also nice before that the PAT0..PAT2 bitfields were used to define a
> good pattern, since it's easier to match with the datasheet.
This one was much suggestion. Not particularly important one.
Personally if a datasheet is pointlessly confusing I tend to ignore it.
This is a two bit field as the bits don't have independent meaning!
I'm not strongly tied to it though and as it's an Analog driver and
you all do a good job maintaining the set I'll go with your preference!
I do prefer the naming of PATTERN_GOOD though if nothing else!
>
>
> > +#define AD7780_PATTERN_MASK GENMASK(1, 0)
>
> I like the general usage of GENMASK, but I'm not sure in this case it's
> worth doing. Maybe I missed a discussion somewhere, about doing this
> change, but it is mostly a cosmetic without any functional change.
>
>
> >
> > -#define AD7170_PATTERN (AD7780_PAT0 | AD7170_PAT2)
> > -#define AD7170_PATTERN_MASK (AD7780_PAT0 | AD7780_PAT1 | AD7170_PAT2)
> > +#define AD7170_PATTERN_GOOD 5
> > +#define AD7170_PATTERN_MASK GENMASK(2, 0)
> >
> > #define AD7780_GAIN_MIDPOINT 64
> > #define AD7780_FILTER_MIDPOINT 13350
> > @@ -209,25 +207,25 @@ static const struct ad_sigma_delta_info
> > ad7780_sigma_delta_info = {
> > static const struct ad7780_chip_info ad7780_chip_info_tbl[] = {
> > [ID_AD7170] = {
> > .channel = AD7170_CHANNEL(12, 24),
> > - .pattern = AD7170_PATTERN,
> > + .pattern = AD7170_PATTERN_GOOD,
> > .pattern_mask = AD7170_PATTERN_MASK,
> > .is_ad778x = false,
> > },
> > [ID_AD7171] = {
> > .channel = AD7170_CHANNEL(16, 24),
> > - .pattern = AD7170_PATTERN,
> > + .pattern = AD7170_PATTERN_GOOD,
> > .pattern_mask = AD7170_PATTERN_MASK,
> > .is_ad778x = false,
> > },
> > [ID_AD7780] = {
> > .channel = AD7780_CHANNEL(24, 32),
> > - .pattern = AD7780_PATTERN,
> > + .pattern = AD7780_PATTERN_GOOD,
> > .pattern_mask = AD7780_PATTERN_MASK,
> > .is_ad778x = true,
> > },
> > [ID_AD7781] = {
> > .channel = AD7780_CHANNEL(20, 32),
> > - .pattern = AD7780_PATTERN,
> > + .pattern = AD7780_PATTERN_GOOD,
> > .pattern_mask = AD7780_PATTERN_MASK,
> > .is_ad778x = true,
> > },
> > --
> > 2.21.0
> >
