Re: [PATCH v7 0/4] iio: light: add support for veml6031x00 ALS series

On Tue, Aug 18, 2026 at 01:34:25PM +0200, Javier Carrasco wrote:

These ambient light sensors with I2C interface provide two light
channels (ALS and IR), high/low threshold alarms with configurable
persistence, and a data ready signal.

The devices covered by this driver have the same resolution, and they
share most of their functionality. These are the differences between
them (note that the x belongs to their names, and it is not a wildcard):

 - Device ID: accessible via two 8-bit registers, different values for
   veml6031x00/veml6031x01 and veml60311x00/veml60311x01.
 - I2C address: same grouping, 0x29 and 0x10 I2C addresses.
 - AEC qualification: AEC-Q100 for veml6031x00/veml60311x00 and
   AEC-Q101 for veml6031x01/veml60311x01.

The alarms and the data ready signals share the interrupt pin, and an
interrupt status register must be accessed to identify the source. Such
multiplexing is not new in IIO, and I have followed existing examples
for it. The persistence setting (own attribute) to trigger the alarms
uses the pattern that has already been used for the veml6030.

The device configuration is in general documented in the datasheet and
the application note. There is an exception, though: the activation of
the "active force" mode that is required for the data ready signal must
be carried out in two steps even though the affected bits are located in
the same register: first ALS_AF (active force mode enable) must be set,
and then ALS_TRIG (active force trigger setting) must be enabled. I have
added a brief commentary in the code to explain this behavior, which has
been confirmed by the manufacturer.

The datasheet specifies the scale and integration time for the ALS channel.
Although both settings also affect the measured IR value, no transfer
function, accuracy, or calibration is specified for converting the IR
output into a physical quantity. The IR channel is therefore intended only
as a qualitative indication of the infrared content of the incident light,
rather than as a precision measurement channel. Consequently, the driver
does not expose scale or integration time as IR-channel attributes.

The only functionality that has not been implemented yet is the x0.66
gain (and its x0.165 counterpart when PD_DIV=1), which makes the gts
helpers less usable due to the conversions required. It is indeed an
uncommon gain to use (there are x0.5 and x0.125 gains) with no known
use-case at the moment that justifies making adjustments to the gts
helpers or adding artificial conversions to make it work.

This driver has been tested with the four supported devices separately
as well as in pairs where the I2C addresses don't overlap.

Reviewed-by: Andy Shevchenko <andy@kernel.org>
for all patches, but DT.

There are minor things that may be addressed later, or in next version if asked
for other reasons.

-- 
With Best Regards,
Andy Shevchenko