Re: [PATCH v7 0/4] iio: light: add support for veml6031x00 ALS series
Jonathan Cameron <[email protected]>
| Newsgroups | org.kernel.vger.linux-iio,org.kernel.vger.linux-devicetree,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <20260819020426.1de53bce@jic23-huawei> |
On Tue, 18 Aug 2026 17:02:35 +0300 Andy Shevchenko <[email protected]> wrote: > 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 <[email protected]> > for all patches, but DT. > > There are minor things that may be addressed later, or in next version if asked > for other reasons. > Assuming remaining discussion resolves, there is just enough requested here that I think a v8 makes sense. This is particularly because of where we are in the cycle and the massive amount of time we have as a result. Note I didn't find anything that Andy hadn't already raised. Looking nice! Jonathan