Re: [PATCH 3/3] staging: iio: ad5933: use iio_device_attach_kfifo_buffer() helper

Ardelean, Alexandru
2020-04-06T07:44:03Z

On Sun, 2020-04-05 at 11:49 +0100, Jonathan Cameron wrote:
> [External]
>
> On Wed, 1 Apr 2020 15:59:36 +0300
> Alexandru Ardelean <alexandru.ardelean@analog.com> wrote:
>
> > This driver calls iio_kfifo_allocate() vs devm_iio_kfifo_allocate(). But
> > the conversion is still simpler here, and cleans-up/reduces some error
> > paths.
> >
> > Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
>
> This mixes devm managed stuff an unmanaged. Hence it fails the 'obviously
> correct'
> test. If you wanted to do this you'd first need to sort out the unmanaged
> bits to be automatically unwound (regulators and clocks). Or potentially
> reorder
> the driver so those happen after this allocation is done.
>

Yeah.
I was a bit sloppy here.
I think tried a broader cleanup/rework would be a better idea here.

> Thanks,
>
> Jonathan
>
> > ---
> > .../staging/iio/impedance-analyzer/ad5933.c | 28 ++++---------------
> > 1 file changed, 5 insertions(+), 23 deletions(-)
> >
> > diff --git a/drivers/staging/iio/impedance-analyzer/ad5933.c
> > b/drivers/staging/iio/impedance-analyzer/ad5933.c
> > index af0bcf95ee8a..7bde93c6dd74 100644
> > --- a/drivers/staging/iio/impedance-analyzer/ad5933.c
> > +++ b/drivers/staging/iio/impedance-analyzer/ad5933.c
> > @@ -602,22 +602,6 @@ static const struct iio_buffer_setup_ops
> > ad5933_ring_setup_ops = {
> > .postdisable = ad5933_ring_postdisable,
> > };
> >
> > -static int ad5933_register_ring_funcs_and_init(struct iio_dev *indio_dev)
> > -{
> > - struct iio_buffer *buffer;
> > -
> > - buffer = iio_kfifo_allocate();
> > - if (!buffer)
> > - return -ENOMEM;
> > -
> > - iio_device_attach_buffer(indio_dev, buffer);
> > -
> > - /* Ring buffer functions - here trigger setup related */
> > - indio_dev->setup_ops = &ad5933_ring_setup_ops;
> > -
> > - return 0;
> > -}
> > -
> > static void ad5933_work(struct work_struct *work)
> > {
> > struct ad5933_state *st = container_of(work,
> > @@ -738,26 +722,25 @@ static int ad5933_probe(struct i2c_client *client,
> > indio_dev->dev.parent = &client->dev;
> > indio_dev->info = &ad5933_info;
> > indio_dev->name = id->name;
> > - indio_dev->modes = (INDIO_BUFFER_SOFTWARE | INDIO_DIRECT_MODE);
> > + indio_dev->modes = INDIO_DIRECT_MODE;
> > indio_dev->channels = ad5933_channels;
> > indio_dev->num_channels = ARRAY_SIZE(ad5933_channels);
> >
> > - ret = ad5933_register_ring_funcs_and_init(indio_dev);
> > + ret = iio_device_attach_kfifo_buffer(indio_dev, INDIO_BUFFER_SOFTWARE,
> > + &ad5933_ring_setup_ops);
> > if (ret)
> > goto error_disable_mclk;
> >
> > ret = ad5933_setup(st);
> > if (ret)
> > - goto error_unreg_ring;
> > + goto error_disable_mclk;
> >
> > ret = iio_device_register(indio_dev);
> > if (ret)
> > - goto error_unreg_ring;
> > + goto error_disable_mclk;
> >
> > return 0;
> >
> > -error_unreg_ring:
> > - iio_kfifo_free(indio_dev->buffer);
> > error_disable_mclk:
> > clk_disable_unprepare(st->mclk);
> > error_disable_reg:
> > @@ -772,7 +755,6 @@ static int ad5933_remove(struct i2c_client *client)
> > struct ad5933_state *st = iio_priv(indio_dev);
> >
> > iio_device_unregister(indio_dev);
> > - iio_kfifo_free(indio_dev->buffer);
> > regulator_disable(st->reg);
> > clk_disable_unprepare(st->mclk);
> >