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 <20211024091627.28031-3-andriy.tryshnivskyy@opensynergy.com> <20211028150842.2e309268@jic23-huawei>
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From:   Jyoti Bhayana <jbhayana@google.com>
Date:   Thu, 28 Oct 2021 11:52:12 -0700
Message-ID: <CA+=V6c0VNhC+GFbjCUP=3EtfQz-_n9mbKzAnzDYCze6Cqkrx9g@mail.gmail.com>
Subject: Re: [PATCH v7 2/2] iio/scmi: Add reading "raw" attribute.
To:     Jonathan Cameron <jic23@kernel.org>
Cc:     Andriy Tryshnivskyy <andriy.tryshnivskyy@opensynergy.com>,
        lars@metafoo.de, linux-iio@vger.kernel.org,
        linux-kernel@vger.kernel.org, Vasyl.Vavrychuk@opensynergy.com,
        andy.shevchenko@gmail.com
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Acked-by: Jyoti Bhayana <jbhayana@google.com>


On Thu, Oct 28, 2021 at 7:04 AM Jonathan Cameron <jic23@kernel.org> wrote:
>
> On Sun, 24 Oct 2021 12:16:27 +0300
> Andriy Tryshnivskyy <andriy.tryshnivskyy@opensynergy.com> wrote:
>
> > Add IIO_CHAN_INFO_RAW to the mask and implement corresponding
> > reading "raw" attribute in scmi_iio_read_raw.
> >
> > Signed-off-by: Andriy Tryshnivskyy <andriy.tryshnivskyy@opensynergy.com>
>
> @Jyoti,
>
> looking for your Ack / or Reviewed-by tag for this one.
>
> Thanks,
>
> Jonathan
>
> > ---
> > Changes comparing v6 -> v7:
> > * split into two patches: one for changes in core functionality,
> >   another - for changes in the driver
> >
> > Changes comparing v5 -> v6:
> > * revert v5 changes since with scmi_iio_read_raw() the channel
> >   can't be used by in kernel users (iio-hwmon)
> > * returned to v3 with direct mode
> > * introduce new type IIO_VAL_INT_64 to read 64-bit value
> >
> > Changes comparing v4 -> v5:
> > * call iio_device_release_direct_mode() on error
> > * code cleanup, fix typo
> >
> > Changes comparing v3 -> v4:
> > * do not use scmi_iio_get_raw() for reading raw attribute due to 32-bit
> >   return value limitation (actually I reverted the previous v3)
> > * introduce scmi_iio_read_raw to scmi_iio_ext_info[] which can return
> >   64-bit value
> > * enabling/disabling and reading raw attribute is done in direct mode
> >
> > Changes comparing v2 -> v3:
> > * adaptation for changes in structure scmi_iio_priv (no member
> >   named 'handle')
> >
> > Changes comparing v0 -> v2:
> > * added an error return when the error happened during config_set
> > * removed redundant cast for "readings"
> > * added check if raw value fits 32 bits
> >
> >  drivers/iio/common/scmi_sensors/scmi_iio.c | 57 +++++++++++++++++++++-
> >  1 file changed, 56 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/iio/common/scmi_sensors/scmi_iio.c b/drivers/iio/common/scmi_sensors/scmi_iio.c
> > index 7cf2bf282cef..d538bf3ab1ef 100644
> > --- a/drivers/iio/common/scmi_sensors/scmi_iio.c
> > +++ b/drivers/iio/common/scmi_sensors/scmi_iio.c
> > @@ -279,6 +279,52 @@ static int scmi_iio_get_odr_val(struct iio_dev *iio_dev, int *val, int *val2)
> >       return 0;
> >  }
> >
> > +static int scmi_iio_read_channel_data(struct iio_dev *iio_dev,
> > +                          struct iio_chan_spec const *ch, int *val, int *val2)
> > +{
> > +     struct scmi_iio_priv *sensor = iio_priv(iio_dev);
> > +     u32 sensor_config;
> > +     struct scmi_sensor_reading readings[SCMI_IIO_NUM_OF_AXIS];
> > +     int err;
> > +
> > +     sensor_config = FIELD_PREP(SCMI_SENS_CFG_SENSOR_ENABLED_MASK,
> > +                                     SCMI_SENS_CFG_SENSOR_ENABLE);
> > +     err = sensor->sensor_ops->config_set(
> > +             sensor->ph, sensor->sensor_info->id, sensor_config);
> > +     if (err) {
> > +             dev_err(&iio_dev->dev,
> > +                     "Error in enabling sensor %s err %d",
> > +                     sensor->sensor_info->name, err);
> > +             return err;
> > +     }
> > +
> > +     err = sensor->sensor_ops->reading_get_timestamped(
> > +             sensor->ph, sensor->sensor_info->id,
> > +             sensor->sensor_info->num_axis, readings);
> > +     if (err) {
> > +             dev_err(&iio_dev->dev,
> > +                     "Error in reading raw attribute for sensor %s err %d",
> > +                     sensor->sensor_info->name, err);
> > +             return err;
> > +     }
> > +
> > +     sensor_config = FIELD_PREP(SCMI_SENS_CFG_SENSOR_ENABLED_MASK,
> > +                                     SCMI_SENS_CFG_SENSOR_DISABLE);
> > +     err = sensor->sensor_ops->config_set(
> > +             sensor->ph, sensor->sensor_info->id, sensor_config);
> > +     if (err) {
> > +             dev_err(&iio_dev->dev,
> > +                     "Error in disabling sensor %s err %d",
> > +                     sensor->sensor_info->name, err);
> > +             return err;
> > +     }
> > +
> > +     *val = lower_32_bits(readings[ch->scan_index].value);
> > +     *val2 = upper_32_bits(readings[ch->scan_index].value);
> > +
> > +     return IIO_VAL_INT_64;
> > +}
> > +
> >  static int scmi_iio_read_raw(struct iio_dev *iio_dev,
> >                            struct iio_chan_spec const *ch, int *val,
> >                            int *val2, long mask)
> > @@ -300,6 +346,14 @@ static int scmi_iio_read_raw(struct iio_dev *iio_dev,
> >       case IIO_CHAN_INFO_SAMP_FREQ:
> >               ret = scmi_iio_get_odr_val(iio_dev, val, val2);
> >               return ret ? ret : IIO_VAL_INT_PLUS_MICRO;
> > +     case IIO_CHAN_INFO_RAW:
> > +             ret = iio_device_claim_direct_mode(iio_dev);
> > +             if (ret)
> > +                     return ret;
> > +
> > +             ret = scmi_iio_read_channel_data(iio_dev, ch, val, val2);
> > +             iio_device_release_direct_mode(iio_dev);
> > +             return ret;
> >       default:
> >               return -EINVAL;
> >       }
> > @@ -381,7 +435,8 @@ static void scmi_iio_set_data_channel(struct iio_chan_spec *iio_chan,
> >       iio_chan->type = type;
> >       iio_chan->modified = 1;
> >       iio_chan->channel2 = mod;
> > -     iio_chan->info_mask_separate = BIT(IIO_CHAN_INFO_SCALE);
> > +     iio_chan->info_mask_separate =
> > +             BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_RAW);
> >       iio_chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SAMP_FREQ);
> >       iio_chan->info_mask_shared_by_type_available =
> >               BIT(IIO_CHAN_INFO_SAMP_FREQ);
>