Re: [PATCH] iio: light: cm32181: add support for the CM32183

[Joshua Crofts <joshua.crofts1@gmail.com>]

On Sun, 11 Oct 2026 08:48:56 +0000 (UTC)
Zixin Wang <ywp1023456@foxmail.com> wrote:

> The CM32183 is another member of the Capella CM3218x ambient light
> sensor family. Its device ID register (0x07) returns 0x83 in the low
> byte, following the same scheme as the already supported parts:
> 
>     CM3218  -> 0x18
>     CM32181 -> 0x81
>     CM32182 -> 0x82
>     CM32183 -> 0x83
> 
> The driver falls through to the default branch of the ID switch and
> returns -ENODEV, so probe() fails even though the device is present and
> functional:
> 
>     cm32181 i2c-CPLM3218:00: cm32181_probe: register init failed
> 
> This was observed on an H3C MegaBook 14 (Intel Core Ultra 5 226V, Lunar
> Lake). Its DSDT declares the sensor as:
> 
>     Device (LSRD) {
>         Name (_HID, "CPLM3218")
>         Name (_CID, "CPLM3218")
>         Name (_UID, 1)
>     }
> 
> on I2C at address 0x29, and additionally provides the vendor
> initialisation and calibration objects that this driver already parses.
> CPM0[0] reports a device-id of 32183, and CPM1 provides lux_per_bit =
> 2200 and calibscale = 265859.
> 
> Treat the CM32183 like the CM32181.
> 
> Measurements on the above machine confirm the register layout matches:
> the power-on value of the CMD register (0x0001) has bit 0 set, which is
> CM32181_CMD_ALS_DISABLE, and register 0x04 is the ALS data register.
> With this change the driver binds, the ACPI-provided initialisation
> values are written and the CPM1 calibration is taken into account
> (in_illuminance_calibscale reads back 265859). The reported illuminance
> tracks ambient light without saturating.
> 

Code is good, but no need for the above to go into the commit message.
I'd have a commit message like:

Add the device ID for the CM32183. The device has the same register
layout as the CM32181.

What you wrote should IMO go under the ---.

-- 
Kind regards,
Joshua Crofts