Re: [PATCH AUTOSEL 5.4 137/350] iio: pressure: zpa2326: fix iio_triggered_buffer_postenable position

From: Jonathan Cameron
Date: Sun Dec 15 2019 - 11:06:22 EST


On Tue, 10 Dec 2019 16:04:02 -0500
Sasha Levin <sashal@xxxxxxxxxx> wrote:

> From: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
>
> [ Upstream commit fe2392c67db9730d46f11fc4fadfa7bffa8843fa ]
>
> The iio_triggered_buffer_{predisable,postenable} functions attach/detach
> the poll functions.
>
> The iio_triggered_buffer_postenable() should be called before (to attach
> the poll func) and then the
>
> The iio_triggered_buffer_predisable() function is hooked directly without
> anything, which is probably fine, as the postenable() version seems to also
> do some reset/wake-up of the device.
> This will mean it will be easier when removing it; i.e. it just gets
> removed.

Ah. I should have added a note to this one as well. This is more general
rework, that is a fix in the sense of bringing things towards a standard
way of doing things rather than 'fixing' a known bug.

Alex, for any more of these, lets not have fix in the title (though they
sort of do 'fix' things).

Thanks,

Jonathan

>
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
> Signed-off-by: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx>
> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
> ---
> drivers/iio/pressure/zpa2326.c | 16 +++++++++-------
> 1 file changed, 9 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/iio/pressure/zpa2326.c b/drivers/iio/pressure/zpa2326.c
> index 9d0d07930236e..99dfe33ee402f 100644
> --- a/drivers/iio/pressure/zpa2326.c
> +++ b/drivers/iio/pressure/zpa2326.c
> @@ -1243,6 +1243,11 @@ static int zpa2326_postenable_buffer(struct iio_dev *indio_dev)
> const struct zpa2326_private *priv = iio_priv(indio_dev);
> int err;
>
> + /* Plug our own trigger event handler. */
> + err = iio_triggered_buffer_postenable(indio_dev);
> + if (err)
> + goto err;
> +
> if (!priv->waken) {
> /*
> * We were already power supplied. Just clear hardware FIFO to
> @@ -1250,7 +1255,7 @@ static int zpa2326_postenable_buffer(struct iio_dev *indio_dev)
> */
> err = zpa2326_clear_fifo(indio_dev, 0);
> if (err)
> - goto err;
> + goto err_buffer_predisable;
> }
>
> if (!iio_trigger_using_own(indio_dev) && priv->waken) {
> @@ -1260,16 +1265,13 @@ static int zpa2326_postenable_buffer(struct iio_dev *indio_dev)
> */
> err = zpa2326_config_oneshot(indio_dev, priv->irq);
> if (err)
> - goto err;
> + goto err_buffer_predisable;
> }
>
> - /* Plug our own trigger event handler. */
> - err = iio_triggered_buffer_postenable(indio_dev);
> - if (err)
> - goto err;
> -
> return 0;
>
> +err_buffer_predisable:
> + iio_triggered_buffer_predisable(indio_dev);
> err:
> zpa2326_err(indio_dev, "failed to enable buffering (%d)", err);
>