Re: [PATCH v5 05/10] iio: backend: extend features

[Nuno Sá]

On Tue, 2024-10-08 at 17:43 +0200, Angelo Dureghello wrote:
> From: Angelo Dureghello <adureghello@xxxxxxxxxxxx>
> 
> Extend backend features with new calls needed later on this
> patchset from axi version of ad3552r.
> 
> The follwoing calls are added:
> 
> iio_backend_ddr_enable
> 	enable ddr bus transfer
> iio_backend_ddr_disable
> 	disable ddr bus transfer
> iio_backend_data_stream_enable
> 	enable data stream over bus interface
> iio_backend_data_stream_disable
> 	disable data stream over bus interface
> iio_backend_data_transfer_addr
> 	define the target register address where the DAC sample
> 	will be written.
> 
> Signed-off-by: Angelo Dureghello <adureghello@xxxxxxxxxxxx>
> ---

nit: On the commit message you could properly name functions like 
iio_backend_ddr_enable() etc... If you need a v6, please have that in mind.
Anyways:

Reviewed-by: Nuno Sa <nuno.sa@xxxxxxxxxx>

>  drivers/iio/industrialio-backend.c | 78
> ++++++++++++++++++++++++++++++++++++++
>  include/linux/iio/backend.h        | 17 +++++++++
>  2 files changed, 95 insertions(+)
> 
> diff --git a/drivers/iio/industrialio-backend.c b/drivers/iio/industrialio-
> backend.c
> index 20b3b5212da7..81f3d24f0c50 100644
> --- a/drivers/iio/industrialio-backend.c
> +++ b/drivers/iio/industrialio-backend.c
> @@ -718,6 +718,84 @@ static int __devm_iio_backend_get(struct device *dev,
> struct iio_backend *back)
>  	return 0;
>  }
>  
> +/**
> + * iio_backend_ddr_enable - Enable interface DDR (Double Data Rate) mode
> + * @back: Backend device
> + *
> + * Enable DDR, data is generated by the IP at each front (raising and
> falling)
> + * of the bus clock signal.
> + *
> + * RETURNS:
> + * 0 on success, negative error number on failure.
> + */
> +int iio_backend_ddr_enable(struct iio_backend *back)
> +{
> +	return iio_backend_op_call(back, ddr_enable);
> +}
> +EXPORT_SYMBOL_NS_GPL(iio_backend_ddr_enable, IIO_BACKEND);
> +
> +/**
> + * iio_backend_ddr_disable - Disable interface DDR (Double Data Rate) mode
> + * @back: Backend device
> + *
> + * Disable DDR, setting into SDR mode (Single Data Rate).
> + *
> + * RETURNS:
> + * 0 on success, negative error number on failure.
> + */
> +int iio_backend_ddr_disable(struct iio_backend *back)
> +{
> +	return iio_backend_op_call(back, ddr_disable);
> +}
> +EXPORT_SYMBOL_NS_GPL(iio_backend_ddr_disable, IIO_BACKEND);
> +
> +/**
> + * iio_backend_data_stream_enable - Enable data stream
> + * @back: Backend device
> + *
> + * Enable data stream over the bus interface.
> + *
> + * RETURNS:
> + * 0 on success, negative error number on failure.
> + */
> +int iio_backend_data_stream_enable(struct iio_backend *back)
> +{
> +	return iio_backend_op_call(back, data_stream_enable);
> +}
> +EXPORT_SYMBOL_NS_GPL(iio_backend_data_stream_enable, IIO_BACKEND);
> +
> +/**
> + * iio_backend_data_stream_disable - Disable data stream
> + * @back: Backend device
> + *
> + * Disable data stream over the bus interface.
> + *
> + * RETURNS:
> + * 0 on success, negative error number on failure.
> + */
> +int iio_backend_data_stream_disable(struct iio_backend *back)
> +{
> +	return iio_backend_op_call(back, data_stream_disable);
> +}
> +EXPORT_SYMBOL_NS_GPL(iio_backend_data_stream_disable, IIO_BACKEND);
> +
> +/**
> + * iio_backend_data_transfer_addr - Set data address.
> + * @back: Backend device
> + * @address: Data register address
> + *
> + * Some devices may need to inform the backend about an address
> + * where to read or write the data.
> + *
> + * RETURNS:
> + * 0 on success, negative error number on failure.
> + */
> +int iio_backend_data_transfer_addr(struct iio_backend *back, u32 address)
> +{
> +	return iio_backend_op_call(back, data_transfer_addr, address);
> +}
> +EXPORT_SYMBOL_NS_GPL(iio_backend_data_transfer_addr, IIO_BACKEND);
> +
>  static struct iio_backend *__devm_iio_backend_fwnode_get(struct device *dev,
> const char *name,
>  							 struct fwnode_handle
> *fwnode)
>  {
> diff --git a/include/linux/iio/backend.h b/include/linux/iio/backend.h
> index 37d56914d485..10be00f3b120 100644
> --- a/include/linux/iio/backend.h
> +++ b/include/linux/iio/backend.h
> @@ -14,12 +14,14 @@ struct iio_dev;
>  enum iio_backend_data_type {
>  	IIO_BACKEND_TWOS_COMPLEMENT,
>  	IIO_BACKEND_OFFSET_BINARY,
> +	IIO_BACKEND_DATA_UNSIGNED,
>  	IIO_BACKEND_DATA_TYPE_MAX
>  };
>  
>  enum iio_backend_data_source {
>  	IIO_BACKEND_INTERNAL_CONTINUOUS_WAVE,
>  	IIO_BACKEND_EXTERNAL,
> +	IIO_BACKEND_INTERNAL_RAMP_16BIT,
>  	IIO_BACKEND_DATA_SOURCE_MAX
>  };
>  
> @@ -89,6 +91,11 @@ enum iio_backend_sample_trigger {
>   * @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.
> + * @ddr_enable: Enable interface DDR (Double Data Rate) mode.
> + * @ddr_disable: Disable interface DDR (Double Data Rate) mode.
> + * @data_stream_enable: Enable data stream.
> + * @data_stream_disable: Disable data stream.
> + * @data_transfer_addr: Set data address.
>   **/
>  struct iio_backend_ops {
>  	int (*enable)(struct iio_backend *back);
> @@ -129,6 +136,11 @@ 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 (*ddr_enable)(struct iio_backend *back);
> +	int (*ddr_disable)(struct iio_backend *back);
> +	int (*data_stream_enable)(struct iio_backend *back);
> +	int (*data_stream_disable)(struct iio_backend *back);
> +	int (*data_transfer_addr)(struct iio_backend *back, u32 address);
>  };
>  
>  /**
> @@ -164,6 +176,11 @@ 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_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);
> +int iio_backend_data_stream_disable(struct iio_backend *back);
> +int iio_backend_data_transfer_addr(struct iio_backend *back, u32 address);
>  ssize_t iio_backend_ext_info_set(struct iio_dev *indio_dev, uintptr_t
> private,
>  				 const struct iio_chan_spec *chan,
>  				 const char *buf, size_t len);
>