> From: Vitor Soares <soares@synopsys.com>
> Date: Thu, Jul 11, 2019 at 11:12:34
> 
> > Hi Lorenzo,
> > 
> > From: Lorenzo Bianconi <lorenzo@kernel.org>
> > Date: Wed, Jul 10, 2019 at 20:44:05
> > 
> > > > For today the st_lsm6dsx driver support LSM6DSO and LSM6DSR sensor only in
> > > > spi and i2c mode.
> > > > 
> > > > The LSM6DSO and LSM6DSR are also i3c capable so lets give i3c support to
> > > > them.
> > > 
> > > Hi Vitor,
> > > 
> > > just few comments inline.
> > > 
> > > Regards,
> > > Lorenzo
> > > 
> > > > 
> > > > Signed-off-by: Vitor Soares <vitor.soares@synopsys.com>
> > > > Acked-by: Lorenzo Bianconi <lorenzo@kernel.org>
> > > > ---
> > > > Changes in v3:
> > > >   Remove unnecessary st_lsm6dsx_i3c_data table used to hold device name
> > > >   Use st_lsm6dsx_probe new form
> > > > 
> > > > Changes in v2:
> > > >   Add support for LSM6DSR
> > > >   Set pm_ops to st_lsm6dsx_pm_ops
> > > > 
> > > >  drivers/iio/imu/st_lsm6dsx/Kconfig          |  8 +++-
> > > >  drivers/iio/imu/st_lsm6dsx/Makefile         |  1 +
> > > >  drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i3c.c | 61 +++++++++++++++++++++++++++++
> > > >  3 files changed, 69 insertions(+), 1 deletion(-)
> > > >  create mode 100644 drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_i3c.c
> > > > 
> > > 
> > > [...]
> > > > +static int st_lsm6dsx_i3c_probe(struct i3c_device *i3cdev)
> > > > +{
> > > > +	const struct i3c_device_id *id = i3c_device_match_id(i3cdev,
> > > > +							    st_lsm6dsx_i3c_ids);
> > > 
> > > i3c_device_match_id can theoretically fail so is it better to check
> > > return value here? (maybe I am too paranoid :))
> 
> I was preparing the patch and if the i3c_device_match_id() fail it return 
> NULL so the st_lsm6dsx_probe() will fail automatically.
> Checking the spi_get_device_id(), the drivers don't test the return value 
> too.

multiple drivers deference it directly so I am fine to skip this check.

Regards,
Lorenzo

> 
> Do you think it is really necessary to test it before the 
> st_lsm6dsx_probe() function?
> 
> Best regards,
> Vitor Soares