Re: [PATCH v3 01/11] iio: backend: add support for filter config

["Nuno Sá" <noname.nuno@gmail.com>]

On Fri, 2025-04-25 at 14:25 +0300, Antoniu Miclaus wrote:
> Add backend support for digital filter type selection.
> 
> This setting can be adjusted within the IP cores interfacing devices.
> 
> The IP core can be configured based on the state of the actual
> digital filter configuration of the part.
> 
> Signed-off-by: Antoniu Miclaus <antoniu.miclaus@analog.com>
> ---

This one LGTM:

Reviewed-by: Nuno Sá <nuno.sa@analog.com>

> changes in v3:
>  - update function to set the actual filter type instead of just
> enable/disable.
>  drivers/iio/industrialio-backend.c | 15 +++++++++++++++
>  include/linux/iio/backend.h        | 13 +++++++++++++
>  2 files changed, 28 insertions(+)
> 
> diff --git a/drivers/iio/industrialio-backend.c b/drivers/iio/industrialio-
> backend.c
> index d4ad36f54090..2d28eabb1607 100644
> --- a/drivers/iio/industrialio-backend.c
> +++ b/drivers/iio/industrialio-backend.c
> @@ -778,6 +778,21 @@ static int __devm_iio_backend_get(struct device *dev,
> struct iio_backend *back)
>  	return 0;
>  }
>  
> +/**
> + * iio_backend_filter_type_set - Set filter type
> + * @back: Backend device
> + * @type: Filter type.
> + *
> + * RETURNS:
> + * 0 on success, negative error number on failure.
> + */
> +int iio_backend_filter_type_set(struct iio_backend *back,
> +				enum iio_backend_filter_type type)
> +{
> +	return iio_backend_op_call(back, filter_type_set, type);
> +}
> +EXPORT_SYMBOL_NS_GPL(iio_backend_filter_type_set, "IIO_BACKEND");
> +
>  /**
>   * iio_backend_ddr_enable - Enable interface DDR (Double Data Rate) mode
>   * @back: Backend device
> diff --git a/include/linux/iio/backend.h b/include/linux/iio/backend.h
> index e45b7dfbec35..5526800f5d4a 100644
> --- a/include/linux/iio/backend.h
> +++ b/include/linux/iio/backend.h
> @@ -76,6 +76,14 @@ enum iio_backend_interface_type {
>  	IIO_BACKEND_INTERFACE_MAX
>  };
>  
> +enum iio_backend_filter_type {
> +	IIO_BACKEND_FILTER_TYPE_DISABLED,
> +	IIO_BACKEND_FILTER_TYPE_SINC1,
> +	IIO_BACKEND_FILTER_TYPE_SINC5,
> +	IIO_BACKEND_FILTER_TYPE_SINC5_PLUS_COMP,
> +	IIO_BACKEND_FILTER_TYPE_MAX
> +};
> +
>  /**
>   * struct iio_backend_ops - operations structure for an iio_backend
>   * @enable: Enable backend.
> @@ -100,6 +108,7 @@ enum iio_backend_interface_type {
>   * @read_raw: Read a channel attribute from a backend device
>   * @debugfs_print_chan_status: Print channel status into a buffer.
>   * @debugfs_reg_access: Read or write register value of backend.
> + * @filter_type_set: Set filter type.
>   * @ddr_enable: Enable interface DDR (Double Data Rate) mode.
>   * @ddr_disable: Disable interface DDR (Double Data Rate) mode.
>   * @data_stream_enable: Enable data stream.
> @@ -150,6 +159,8 @@ struct iio_backend_ops {
>  					 size_t len);
>  	int (*debugfs_reg_access)(struct iio_backend *back, unsigned int reg,
>  				  unsigned int writeval, unsigned int
> *readval);
> +	int (*filter_type_set)(struct iio_backend *back,
> +			       enum iio_backend_filter_type type);
>  	int (*ddr_enable)(struct iio_backend *back);
>  	int (*ddr_disable)(struct iio_backend *back);
>  	int (*data_stream_enable)(struct iio_backend *back);
> @@ -190,6 +201,8 @@ int iio_backend_data_sample_trigger(struct iio_backend
> *back,
>  int devm_iio_backend_request_buffer(struct device *dev,
>  				    struct iio_backend *back,
>  				    struct iio_dev *indio_dev);
> +int iio_backend_filter_type_set(struct iio_backend *back,
> +				enum iio_backend_filter_type type);
>  int iio_backend_ddr_enable(struct iio_backend *back);
>  int iio_backend_ddr_disable(struct iio_backend *back);
>  int iio_backend_data_stream_enable(struct iio_backend *back);