Re: [PATCH v2 3/3] iio: imu: st_lsm6dsx: Add support for rotation sensor

[Lorenzo Bianconi <lorenzo@kernel.org>]

[-- Attachment #1: Type: text/plain, Size: 2074 bytes --]

On Jan 15, Andy Shevchenko wrote:
> On Thu, Jan 15, 2026 at 02:32:11PM +0100, Lorenzo Bianconi wrote:
> > > Some IMU chips in the LSM6DSX family have sensor fusion features that
> > > combine data from the accelerometer and gyroscope. One of these features
> > > generates rotation vector data and makes it available in the hardware
> > > FIFO as a quaternion (more specifically, the X, Y and Z components of the
> > > quaternion vector, expressed as 16-bit half-precision floating-point
> > > numbers).
> > > 
> > > Add support for a new sensor instance that allows receiving sensor fusion
> > > data, by defining a new struct st_lsm6dsx_sf_settings (which contains
> > > chip-specific details for the sensor fusion functionality), and adding this
> > > struct as a new field in struct st_lsm6dsx_settings. In st_lsm6dsx_core.c,
> > > populate this new struct for the LSM6DSV and LSM6DSV16X chips, and add the
> > > logic to initialize an additional IIO device if this struct is populated
> > > for the hardware type being probed.
> > > Note: a new IIO device is being defined (as opposed to adding channels to
> > > an existing device) because the rate at which sensor fusion data is
> > > generated may not match the data rate from any of the existing devices.
> > > 
> > > Tested on LSMDSV16X.
> 
> ...
> 
> > > +	settings = &sensor->hw->settings->sf_settings;
> > > +	switch (mask) {
> > > +	case IIO_CHAN_INFO_SAMP_FREQ: {
> > > +		u32 odr_mHz;
> > > +		u8 odr_val;
> > > +
> > > +		odr_mHz = val * MILLI + val2 * MILLI / MICRO;
> > > +		err = st_lsm6dsx_sf_get_odr_val(settings, odr_mHz, &odr_val);
> > > +		if (err)
> > > +			return err;
> > > +
> > > +		sensor->hwfifo_odr_mHz = odr_mHz;
> > > +		return 0;
> > 
> > break;
> > 
> > > +	}
> > > +	default:
> > > +		return -EINVAL;
> > 
> > break;
> > 
> > > +	}
> > 
> > return err;
> 
> Why?

I guess it is more clear, but just a Nit, I can live with the current implementation.

Regards,
Lorenzo

> 
> -- 
> With Best Regards,
> Andy Shevchenko
> 
> 

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 228 bytes --]