Re: [PATCH v2 2/6] iio: core: add iio_device_set_parent() helper

[Jonathan Cameron <jic23@kernel.org>]

On Wed, 3 Jun 2020 14:40:19 +0300
Alexandru Ardelean <alexandru.ardelean@analog.com> wrote:

> By default, the device allocation will also assign a parent device to the
> IIO device object. In cases where devm_iio_device_alloc() is used,
> sometimes the parent device must be different than the device used to
> manage the allocation.
> 
> In that case, this helper should be used to change the parent, hence the
> requirement to call this between allocation & registration.
> 
> This pattern/requirement is not very common in the IIO space, and it may be
> cleaned up later.
> But until then, assigning the parent manually between allocation &
> registration is slightly easier.
> 
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>

That does the job nicely.

Applied,

Jonathan

> ---
>  include/linux/iio/iio.h | 20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)
> 
> diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
> index 91a69f4751aa..5784f8c9508f 100644
> --- a/include/linux/iio/iio.h
> +++ b/include/linux/iio/iio.h
> @@ -649,6 +649,26 @@ static inline struct iio_dev *iio_device_get(struct iio_dev *indio_dev)
>  	return indio_dev ? dev_to_iio_dev(get_device(&indio_dev->dev)) : NULL;
>  }
>  
> +/**
> + * iio_device_set_parent() - assign parent device to the IIO device object
> + * @indio_dev: 		IIO device structure
> + * @parent:		reference to parent device object
> + *
> + * This utility must be called between IIO device allocation
> + * (via devm_iio_device_alloc()) & IIO device registration
> + * (via {devm_}iio_device_register()).
> + * By default, the device allocation will also assign a parent device to
> + * the IIO device object. In cases where devm_iio_device_alloc() is used,
> + * sometimes the parent device must be different than the device used to
> + * manage the allocation.
> + * In that case, this helper should be used to change the parent, hence the
> + * requirement to call this between allocation & registration.
> + **/
> +static inline void iio_device_set_parent(struct iio_dev *indio_dev,
> +					 struct device *parent)
> +{
> +	indio_dev->dev.parent = parent;
> +}
>  
>  /**
>   * iio_device_set_drvdata() - Set device driver data