Re: iio display large numbers

[Jonathan Cameron <Jonathan.Cameron@Huawei.com>]

On Tue, 7 Dec 2021 13:40:19 +0100
Henk <yoda@deathstar2.nl> wrote:

> Hi,
> 
> I derived the LTC6951 driver from an existing analog devices LTC6952 driver.
> However for my situation this clock synthesis/buffer uses quite large 
> output frequencies (2.5GHz) which does not fit in the IIO_VAL_INT size 
> when retrieved with iio_info.
> 
> I wonder if there is a way to represent such long integers within the 
> iio_framework. I believe currently there isn't right?
> 
> Regards,
> 
> Henk
> 

Two options for this.  If the thing we are controlling is the raw channel then
we have the option to provide _scale reflecting the fact that a large value
e.g. GHz is not normally controlled at a Hz granularity.

Where that doesn't apply or the range is really very big we do have the
slightly nasty option of IIO_VAL_INT_64

https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git/commit/?h=testing&id=6bb835f3d00467c9a5e35f4955afa29df96a404e

This is very new, so not in mainline yet, though it is queued up for the
next merge window and should be linux-next.

Hope that helps,

Jonathan