On Sun, 2019-03-24 at 17:49 +0000, Jonathan Cameron wrote:
> [External]
>
>
> On Tue, 19 Mar 2019 11:53:06 +0200
> Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx> wrote:
>
> > From: Lars-Peter Clausen <lars@xxxxxxxxxx>
> >
> > The prepare channel callback will be called before starting a
> > conversion and
> > can be used by the driver to configure the chip according to the
> > selected
> > channel.
> >
> > Signed-off-by: Lars-Peter Clausen <lars@xxxxxxxxxx>
> > Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
>
> Hi Alexandru,
>
> Not without a user.... I.e. I want to see a driver using this before
> I apply it. In of itself, it is fine but right now I can't answer the
> 'why?' question!
Ack.
Will put this into a series that adds a user for this to make it clearer.
At the moment I was just cherry-picking patches from our tree, sending bits
that were easier to apply, and deferring bits that are more complicated to
re-apply.
Thanks
Alex
>
> Jonathan
>
> > ---
> > drivers/iio/adc/ad_sigma_delta.c | 5 +++++
> > include/linux/iio/adc/ad_sigma_delta.h | 13 +++++++++++++
> > 2 files changed, 18 insertions(+)
> >
> > diff --git a/drivers/iio/adc/ad_sigma_delta.c
> > b/drivers/iio/adc/ad_sigma_delta.c
> > index ff5f2da2e1b1..00808838edd8 100644
> > --- a/drivers/iio/adc/ad_sigma_delta.c
> > +++ b/drivers/iio/adc/ad_sigma_delta.c
> > @@ -285,6 +285,7 @@ int ad_sigma_delta_single_conversion(struct iio_dev
> > *indio_dev,
> > return -EBUSY;
> >
> > mutex_lock(&indio_dev->mlock);
> > + ad_sigma_delta_prepare_channel(sigma_delta, chan);
> > ad_sigma_delta_set_channel(sigma_delta, chan->address);
> >
> > spi_bus_lock(sigma_delta->spi->master);
> > @@ -351,6 +352,10 @@ static int ad_sd_buffer_postenable(struct iio_dev
> > *indio_dev)
> >
> > channel = find_first_bit(indio_dev->active_scan_mask,
> > indio_dev->masklength);
> > + ret = ad_sigma_delta_prepare_channel(sigma_delta,
> > + &indio_dev->channels[channel]);
> > + if (ret)
> > + goto err_predisable;
> > ret = ad_sigma_delta_set_channel(sigma_delta,
> > indio_dev->channels[channel].address);
> > if (ret)
> > diff --git a/include/linux/iio/adc/ad_sigma_delta.h
> > b/include/linux/iio/adc/ad_sigma_delta.h
> > index 7e84351fa2c0..21ee12543bdd 100644
> > --- a/include/linux/iio/adc/ad_sigma_delta.h
> > +++ b/include/linux/iio/adc/ad_sigma_delta.h
> > @@ -31,6 +31,8 @@ struct iio_dev;
> >
> > /**
> > * struct ad_sigma_delta_info - Sigma Delta driver specific callbacks
> > and options
> > + * @prepare_channel: Will be called to prepare and configure a
> > channel, may be
> > + * NULL.
> > * @set_channel: Will be called to select the current channel, may be
> > NULL.
> > * @set_mode: Will be called to select the current mode, may be NULL.
> > * @postprocess_sample: Is called for each sampled data word, can be
> > used to
> > @@ -43,6 +45,8 @@ struct iio_dev;
> > * be used.
> > */
> > struct ad_sigma_delta_info {
> > + int (*prepare_channel)(struct ad_sigma_delta *,
> > + const struct iio_chan_spec *);
> > int (*set_channel)(struct ad_sigma_delta *, unsigned int
> > channel);
> > int (*set_mode)(struct ad_sigma_delta *, enum ad_sigma_delta_mode
> > mode);
> > int (*postprocess_sample)(struct ad_sigma_delta *, unsigned int
> > raw_sample);
> > @@ -81,6 +85,15 @@ struct ad_sigma_delta {
> > uint8_t data[4] ____cacheline_aligned;
> > };
> >
> > +static inline int ad_sigma_delta_prepare_channel(struct ad_sigma_delta
> > *sd,
> > + const struct iio_chan_spec *chan)
> > +{
> > + if (sd->info->prepare_channel)
> > + return sd->info->prepare_channel(sd, chan);
> > +
> > + return 0;
> > +}
> > +
> > static inline int ad_sigma_delta_set_channel(struct ad_sigma_delta
> > *sd,
> > unsigned int channel)
> > {
>
>
