Re: [PATCH v1 09/15] iio: adc: ad7768-1: Move buffer allocation to a separate function

[Jonathan Cameron <jic23@kernel.org>]

On Fri, 10 Jan 2025 19:01:35 -0300
Marcelo Schmitt <marcelo.schmitt1@gmail.com> wrote:

> On 01/07, Jonathan Santos wrote:
> > From: Sergiu Cuciurean <sergiu.cuciurean@analog.com>
> > 
> > This change moves the buffer allocation in a separate function, making
> > space for adding another type of iio buffer if needed.
> > 
> > Signed-off-by: Sergiu Cuciurean <sergiu.cuciurean@analog.com>
> > ---
> >  drivers/iio/adc/ad7768-1.c | 64 ++++++++++++++++++++++----------------
> >  1 file changed, 37 insertions(+), 27 deletions(-)
> >   
> ...
> > @@ -625,37 +661,11 @@ static int ad7768_probe(struct spi_device *spi)
> >  		return ret;
> >  	}
> >  
> > -	st->trig = devm_iio_trigger_alloc(&spi->dev, "%s-dev%d",
> > -					  indio_dev->name,
> > -					  iio_device_id(indio_dev));
> > -	if (!st->trig)
> > -		return -ENOMEM;
> > -
> > -	st->trig->ops = &ad7768_trigger_ops;
> > -	iio_trigger_set_drvdata(st->trig, indio_dev);
> > -	ret = devm_iio_trigger_register(&spi->dev, st->trig);
> > -	if (ret)
> > -		return ret;
> > -
> > -	indio_dev->trig = iio_trigger_get(st->trig);
> > -
> > -	init_completion(&st->completion);  
> 
> Isn't the completion also used for single-shot reads?

If so, it should be left in the caller given that. Makes not functional
difference but prevents implication that it is only used for triggered buffer
cases.

> Well, if triggered_buffer_setup fails the whole probe fails and we never get to
> do a single-shot read, but that makes me wonder ... why don't we ever try to
> recover from iio_triggered_buffer_setup()? Should we ever do so?

Nope :)  For it to fail, something is going horribly wrong. Most likely
a bug, so I'm not seeing any reason to carry on.

> 
> > -
> >  	ret = ad7768_set_channel_label(indio_dev, ARRAY_SIZE(ad7768_channels));
> >  	if (ret)
> >  		return ret;
> >  
> > -	ret = devm_request_irq(&spi->dev, spi->irq,
> > -			       &ad7768_interrupt,
> > -			       IRQF_TRIGGER_RISING | IRQF_ONESHOT,
> > -			       indio_dev->name, indio_dev);
> > -	if (ret)
> > -		return ret;
> > -
> > -	ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
> > -					      &iio_pollfunc_store_time,
> > -					      &ad7768_trigger_handler,
> > -					      &ad7768_buffer_ops);
> > +	ret = ad7768_triggered_buffer_alloc(indio_dev);
> >  	if (ret)
> >  		return ret;
> >  
> > -- 
> > 2.34.1
> >