Re: [RFC PATCH] staging: iio: ad9832: modernize ABI and remove dds.h dependency

[David Lechner <dlechner@baylibre.com>]

On 3/5/26 3:03 PM, Bhargav Joshi wrote:
> The AD9832 driver currently relies on legacy custom IIO macros defined
> in dds.h. This triggers checkpatch.pl warnings (NON_OCTAL_PERMISSIONS)
> and, more importantly, exposes a non-standard sysfs ABI (e.g.,
> frequency0, frequency1, phase0-3) directly to user space.
> 
> This patch removes the custom macros and migrates the driver to standard
> IIO API mechanisms:
> - Standard attributes (frequency, phase) now use info_mask_separate.
> - Non standard specific toggles (frequencysymbol, phasesymbol,
>   pincontrol) have been migrated to an ext_info array.
> - Remove dds.h header dependency.
> - Pointless frequency_scale and phase_scale attributes are dropped as
>   suggested by Jonathan in
>   https://lore.kernel.org/linux-iio/20251231180939.422e9e62@jic23-huawei/
> 
> NOTE: This patch introduces an intentional ABI changes. The non-standard
> attributes (out_altvoltage0_frequency0, etc.) have been removed. They
> are replaced by standard attributes (out_altvoltage0_frequency and
> out_altvoltage0_phase). Routing to correct register while writing is
> handled by checking currently active frequencysymbol or phasesymbol.
> 
> Testing: This patch has been strictly compile-tested. I do not have
> access to physical AD9832 hardware. I am submitting this as an RFC to
> see if these changes are acceptable, and to ask if someone with physical
> hardware could test thisg and provide a Tested-by tag.
> 
Since this is changing ABI, I think it would best if someone who actually
has the hardware and plans to use it should be making the changes to
make sure they actually work as intended.