Re: [PATCH v2 1/5] iio: Documentation: update definitions for bufferY and scan_elements

[Mauro Carvalho Chehab <mchehab+huawei@kernel.org>]

Em Wed, 17 Feb 2021 10:34:34 +0200
Alexandru Ardelean <alexandru.ardelean@analog.com> escreveu:

> Since the new change to the IIO buffer infrastructure, the buffer/ and
> scan_elements/ directories have been merged into bufferY/ to have some
> attributes available per-buffer.
> 
> This change updates the ABI docs to reflect this change.
> 
> The hwfifo attributes are not updated, as for now these should be used
> via the legacy buffer/ directory until they are moved into core.
> 
> Signed-off-by: Alexandru Ardelean <alexandru.ardelean@analog.com>
> ---
>  Documentation/ABI/testing/sysfs-bus-iio | 85 +++++++++++++++++++++++++
>  1 file changed, 85 insertions(+)
> 
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
> index d957f5da5c04..f2a72d7fbacb 100644
> --- a/Documentation/ABI/testing/sysfs-bus-iio
> +++ b/Documentation/ABI/testing/sysfs-bus-iio
> @@ -1118,12 +1118,16 @@ Description:
>  
>  What:		/sys/bus/iio/devices/iio:deviceX/buffer/length
>  KernelVersion:	2.6.35
> +What:		/sys/bus/iio/devices/iio:deviceX/bufferY/length
> +KernelVersion:	5.11
>  Contact:	linux-iio@vger.kernel.org
>  Description:
>  		Number of scans contained by the buffer.

The ABI parser doesn't like things like this:

	$ ./scripts/get_abi.pl validate

	Warning: file Documentation/ABI/testing/sysfs-bus-iio#1167:
		What '/sys/bus/iio/devices/iio:deviceX/buffer/length' doesn't have a description

The main reason is that all properties, including KernelVersion, 
Contact and Description are associated to a group of properties.

To be frank, for me that don't work with IIO, the above ABI
description doesn't sound clear.

I mean, what's the difference between
	/sys/bus/iio/devices/iio:deviceX/buffer/length
and
	/sys/bus/iio/devices/iio:deviceX/bufferY/length?


If the intention is to tell that:
	/sys/bus/iio/devices/iio:deviceX/buffer/length
was obsoleted by:
	/sys/bus/iio/devices/iio:deviceX/bufferY/length

IMO, the right thing would be to move the deprecated definition to
	Documentation/ABI/obsolete/

If, on the other hand, both are completely identical and 
non-obsoleted, why to have both APIs? 

Or did you just missed adding a different description for the
new ABI symbols, but this was dropped due to some merge
conflict?

Thanks,
Mauro