4 Commits

Author SHA1 Message Date
Nuno Sa
c66eabcc1c iio: backend: add API for interface tuning
This is in preparation for supporting interface tuning in one for the
devices using the axi-adc backend. The new added interfaces are all
needed for that calibration:

 * iio_backend_test_pattern_set();
 * iio_backend_chan_status();
 * iio_backend_iodelay_set();
 * iio_backend_data_sample_trigger().

Interface tuning is the process of going through a set of known points
(typically by the frontend), change some clk or data delays (or both)
and send/receive some known signal (so called test patterns in this
change). The receiving end (either frontend or the backend) is
responsible for validating the signal and see if it's good or not. The
goal for all of this is to come up with ideal delays at the data
interface level so we can have a proper, more reliable data transfer.

Also note that for some devices we can change the sampling rate
(which typically means changing some reference clock) and that can
affect the data interface. In that case, it's import to run the tuning
algorithm again as the values we had before may no longer be the best (or
even valid) ones.

Signed-off-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20240426-ad9467-new-features-v2-2-6361fc3ba1cc@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2024-04-29 20:53:26 +01:00
Nuno Sa
09415814cd iio: backend: change docs padding
Using tabs and maintaining the start of the docs aligned is a pain and
may lead to lot's of unrelated changes when adding new members. Hence,
let#s change things now and just have a simple space after the member
name.

Signed-off-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20240426-ad9467-new-features-v2-1-6361fc3ba1cc@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2024-04-29 20:53:26 +01:00
Nuno Sa
87800c4342 iio: backend: add new functionality
This adds the needed backend ops for supporting a backend inerfacing
with an high speed dac. The new ops are:

* data_source_set();
* set_sampling_freq();
* extend_chan_spec();
* ext_info_set();
* ext_info_get().

Also to note the new helpers that are meant to be used by the backends
when extending an IIO channel (adding extended info):

* iio_backend_ext_info_set();
* iio_backend_ext_info_get().

Signed-off-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20240419-iio-backend-axi-dac-v4-8-5ca45b4de294@analog.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2024-04-20 15:41:32 +01:00
Nuno Sa
1a97905d3e iio: add the IIO backend framework
This is a Framework to handle complex IIO aggregate devices.

The typical architecture is to have one device as the frontend device which
can be "linked" against one or multiple backend devices. All the IIO and
userspace interface is expected to be registers/managed by the frontend
device which will callback into the backends when needed (to get/set
some configuration that it does not directly control).

The basic framework interface is pretty simple:
 - Backends should register themselves with @devm_iio_backend_register()
 - Frontend devices should get backends with @devm_iio_backend_get()

Signed-off-by: Nuno Sa <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20240210-iio-backend-v11-5-f5242a5fb42a@analog.com
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2024-02-19 19:32:22 +00:00