Re: [PATCH] iio: light: iqs621: remove usage of iio_priv_to_dev()

From: Jeff LaBundy
Date: Fri May 22 2020 - 21:56:43 EST


Hi Alexandru,

On Fri, May 22, 2020 at 09:54:42AM +0300, Alexandru Ardelean wrote:
> We may want to get rid of the iio_priv_to_dev() helper. That's a bit
> uncertain at this point. The reason is that we will hide some of the
> members of the iio_dev structure (to prevent drivers from accessing them
> directly), and that will also mean hiding the implementation of the
> iio_priv_to_dev() helper inside the IIO core.
>
> Hiding the implementation of iio_priv_to_dev() implies that some fast-paths
> may not be fast anymore, so a general idea is to try to get rid of the
> iio_priv_to_dev() altogether.
>
> For this driver, removing iio_priv_to_dev() means keeping a reference
> on the state struct.
>
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@xxxxxxxxxx>
> ---
> drivers/iio/light/iqs621-als.c | 6 ++++--
> 1 file changed, 4 insertions(+), 2 deletions(-)

As with the iqs624 patch:

Acked-by: Jeff LaBundy <jeff@xxxxxxxxxxx>

>
> diff --git a/drivers/iio/light/iqs621-als.c b/drivers/iio/light/iqs621-als.c
> index b2988a782bd0..1a056e2446ab 100644
> --- a/drivers/iio/light/iqs621-als.c
> +++ b/drivers/iio/light/iqs621-als.c
> @@ -36,6 +36,7 @@
>
> struct iqs621_als_private {
> struct iqs62x_core *iqs62x;
> + struct iio_dev *indio_dev;
> struct notifier_block notifier;
> struct mutex lock;
> bool light_en;
> @@ -103,7 +104,7 @@ static int iqs621_als_notifier(struct notifier_block *notifier,
>
> iqs621_als = container_of(notifier, struct iqs621_als_private,
> notifier);
> - indio_dev = iio_priv_to_dev(iqs621_als);
> + indio_dev = iqs621_als->indio_dev;
> timestamp = iio_get_time_ns(indio_dev);
>
> mutex_lock(&iqs621_als->lock);
> @@ -191,7 +192,7 @@ static int iqs621_als_notifier(struct notifier_block *notifier,
> static void iqs621_als_notifier_unregister(void *context)
> {
> struct iqs621_als_private *iqs621_als = context;
> - struct iio_dev *indio_dev = iio_priv_to_dev(iqs621_als);
> + struct iio_dev *indio_dev = iqs621_als->indio_dev;
> int ret;
>
> ret = blocking_notifier_chain_unregister(&iqs621_als->iqs62x->nh,
> @@ -551,6 +552,7 @@ static int iqs621_als_probe(struct platform_device *pdev)
>
> iqs621_als = iio_priv(indio_dev);
> iqs621_als->iqs62x = iqs62x;
> + iqs621_als->indio_dev = indio_dev;
>
> if (iqs62x->dev_desc->prod_num == IQS622_PROD_NUM) {
> ret = regmap_read(iqs62x->regmap, IQS622_IR_THRESH_TOUCH,
> --
> 2.25.1
>

Kind regards,
Jeff LaBundy