On Thu, 07 Dec 2023 11:02:36 +0100
Nuno Sá <noname.nuno@xxxxxxxxx> wrote:
> On Wed, 2023-12-06 at 17:01 -0600, David Lechner wrote:
> > On Tue, Dec 5, 2023 at 11:06 AM Nuno Sa via B4 Relay
> > <devnull+nuno.sa.analog.com@xxxxxxxxxx> wrote:
> > >
> > > From: Nuno Sa <nuno.sa@xxxxxxxxxx>
> > >
> > > When reading in_voltage_scale we can get something like:
> > >
> > > root@analog:/sys/bus/iio/devices/iio:device2# cat in_voltage_scale
> > > 0.038146
> > >
> > > However, when reading the available options:
> > >
> > > root@analog:/sys/bus/iio/devices/iio:device2# cat
> > > in_voltage_scale_available
> > > 2000.000000 2100.000006 2200.000007 2300.000008 2400.000009 2500.000010
> > >
> > > which does not make sense. Moreover, when trying to set a new scale we
> > > get an error because there's no call to __ad9467_get_scale() to give us
> > > values as given when reading in_voltage_scale. Fix it by computing the
> > > available scales during probe and properly pass the list when
> > > .read_available() is called.
> > >
> > > While at it, change to use .read_available() from iio_info. Also note
> > > that to properly fix this, adi-axi-adc.c has to be changed accordingly.
> > >
> > > Fixes: ad6797120238 ("iio: adc: ad9467: add support AD9467 ADC")
> > > Signed-off-by: Nuno Sa <nuno.sa@xxxxxxxxxx>
> > > ---
> > > drivers/iio/adc/ad9467.c | 47 +++++++++++++++++++++++
> > > drivers/iio/adc/adi-axi-adc.c | 74 ++++++++-----------------------------
> > > include/linux/iio/adc/adi-axi-adc.h | 4 ++
> > > 3 files changed, 66 insertions(+), 59 deletions(-)
> > >
> > > diff --git a/drivers/iio/adc/ad9467.c b/drivers/iio/adc/ad9467.c
> > > index badbef2ce9f8..3c8bd6c821a4 100644
> > > --- a/drivers/iio/adc/ad9467.c
> > > +++ b/drivers/iio/adc/ad9467.c
> > > @@ -120,6 +120,7 @@ struct ad9467_state {
> > > struct spi_device *spi;
> > > struct clk *clk;
> > > unsigned int output_mode;
> > > + unsigned int (*scales)[2];
> > >
> > > struct gpio_desc *pwrdown_gpio;
> > > /* ensure consistent state obtained on multiple related accesses */
> > > @@ -216,6 +217,7 @@ static void __ad9467_get_scale(struct adi_axi_adc_conv *conv,
> > > int index,
> > > .channel = _chan, \
> > > .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
> > > BIT(IIO_CHAN_INFO_SAMP_FREQ), \
> > > + .info_mask_shared_by_type_available = BIT(IIO_CHAN_INFO_SCALE), \
> > > .scan_index = _si, \
> > > .scan_type = { \
> > > .sign = _sign, \
> > > @@ -370,6 +372,26 @@ static int ad9467_write_raw(struct adi_axi_adc_conv *conv,
> > > }
> > > }
> > >
> > > +static int ad9467_read_avail(struct adi_axi_adc_conv *conv,
> > > + struct iio_chan_spec const *chan,
> > > + const int **vals, int *type, int *length,
> > > + long mask)
> > > +{
> > > + const struct adi_axi_adc_chip_info *info = conv->chip_info;
> > > + struct ad9467_state *st = adi_axi_adc_conv_priv(conv);
> > > +
> > > + switch (mask) {
> > > + case IIO_CHAN_INFO_SCALE:
> > > + *vals = (const int *)st->scales;
> > > + *type = IIO_VAL_INT_PLUS_MICRO;
> > > + /* Values are stored in a 2D matrix */
> > > + *length = info->num_scales * 2;
> >
> > Maybe use ARRAY_SIZE(*info->scales) here instead of hard-coding 2?
>
> Not to keen on that as the comment should already say everything about the hardcoded
> 2.
>
I don't mind either way, but the comment only says it's a 2D matrix, not that the dimension
is 2 * num_scales - it could easily be 14 * num_scales
> - Nuno Sá
>
>
