Re: [PATCH v2 5/7] iio: core: Add IIO_COVERAGE_PERCENT channel type

[Jonathan Cameron]

On Thu, 14 May 2026 17:46:52 +0300
Liviu Stan <liviu.stan@xxxxxxxxxx> wrote:

> Add a new channel type for sensors that report fractional coverage as
> a percentage. The first user is the ADT7604 leak detector, where the
> value represents the portion of the sensing element that is wetted.
> 
> Signed-off-by: Liviu Stan <liviu.stan@xxxxxxxxxx>
Few things from sashiko that you should address.

One I want to talk more about...

> ---
> Changes in v2:
> - New patch.
> 
>  Documentation/ABI/testing/sysfs-bus-iio | 10 ++++++++++
>  drivers/iio/industrialio-core.c         |  1 +
>  include/uapi/linux/iio/types.h          |  1 +
>  tools/iio/iio_event_monitor.c           |  1 +
>  4 files changed, 13 insertions(+)
> 
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio b/Documentation/ABI/testing/sysfs-bus-iio
> index 925a33fd309a..0570e8b8f5e5 100644
> --- a/Documentation/ABI/testing/sysfs-bus-iio
> +++ b/Documentation/ABI/testing/sysfs-bus-iio
> @@ -1980,6 +1980,16 @@ Description:
>  		Raw (unscaled no offset etc.) resistance reading.
>  		Units after application of scale and offset are ohms.
>  
> +What:		/sys/bus/iio/devices/iio:deviceX/in_coveragepercentX_raw

The bot raises a valid concern about having the unit in the _raw attribute name.
If there is a scale (which incidentally probably needs adding to the ABI - as
_raw on its own is a bit meaningless) then it only becomes percent after
that is applied.

Perhaps
in_coverageX_raw is the way to go?

> +KernelVersion:	6.15
> +Contact:	linux-iio@xxxxxxxxxxxxxxx
> +Description:
> +		Raw (unscaled no offset etc.) coverage reading. Used for sensors
> +		that report fractional coverage as a percentage, such as leak
> +		detectors where the value represents what portion of the sensing
> +		element is wetted. Units after application of scale and offset are
> +		percent.
> +
>  What:		/sys/bus/iio/devices/iio:deviceX/heater_enable
>  KernelVersion:	4.1.0
>  Contact:	linux-iio@xxxxxxxxxxxxxxx
> diff --git a/drivers/iio/industrialio-core.c b/drivers/iio/industrialio-core.c
> index bd6f4f9f4533..ee8ffa2cfbc5 100644
> --- a/drivers/iio/industrialio-core.c
> +++ b/drivers/iio/industrialio-core.c
> @@ -98,6 +98,7 @@ static const char * const iio_chan_type_name_spec[] = {
>  	[IIO_CHROMATICITY] = "chromaticity",
>  	[IIO_ATTENTION] = "attention",
>  	[IIO_ALTCURRENT] = "altcurrent",
> +	[IIO_COVERAGE_PERCENT] = "coveragepercent",
>  };
>  
>  static const char * const iio_modifier_names[] = {
> diff --git a/include/uapi/linux/iio/types.h b/include/uapi/linux/iio/types.h
> index d7c2bb223651..39830dc0cfb1 100644
> --- a/include/uapi/linux/iio/types.h
> +++ b/include/uapi/linux/iio/types.h
> @@ -53,6 +53,7 @@ enum iio_chan_type {
>  	IIO_CHROMATICITY,
>  	IIO_ATTENTION,
>  	IIO_ALTCURRENT,
> +	IIO_COVERAGE_PERCENT,
>  };
>  
>  enum iio_modifier {
> diff --git a/tools/iio/iio_event_monitor.c b/tools/iio/iio_event_monitor.c
> index df6c43d7738d..3339be7fe32c 100644
> --- a/tools/iio/iio_event_monitor.c
> +++ b/tools/iio/iio_event_monitor.c
> @@ -65,6 +65,7 @@ static const char * const iio_chan_type_name_spec[] = {
>  	[IIO_CHROMATICITY] = "chromaticity",
>  	[IIO_ATTENTION] = "attention",
>  	[IIO_ALTCURRENT] = "altcurrent",
> +	[IIO_COVERAGE_PERCENT] = "coveragepercent",
>  };
>  
>  static const char * const iio_ev_type_text[] = {