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charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Wed, Mar 18, 2026 at 8:11=E2=80=AFPM Andy Shevchenko wrote: > > On Wed, Mar 18, 2026 at 02:57:14PM +0530, Archit Anant wrote: > > Reading the regulator voltage via regulator_get_voltage() can be a slow > > operation. Since the reference voltages for this ADC are not expected t= o > > change at runtime, it is inefficient to query the regulator API every > > time userspace reads the IIO_CHAN_INFO_SCALE attribute. > > > > Determine the active reference voltage (either VREF or VCC) during > > probe() and cache it in the state structure. This improves the > > performance of ad799x_read_raw() and removes the dependency on the > > regulator pointers during fast-path reads. > > ... > > > case IIO_CHAN_INFO_SCALE: > > - if (st->vref) > > - ret =3D regulator_get_voltage(st->vref); > > - else > > - ret =3D regulator_get_voltage(st->reg); > > - > > - if (ret < 0) > > - return ret; > > - *val =3D ret / 1000; > > + *val =3D st->vref_uV / MILLI; > > Not sure I understand properly this MILLI in conjunction with FRACTIONAL_= LOG2 > below. Is this simply millivolts? Then we have "(MICRO / MILLI)" pattern = as > of today to show that in a better way. My bad, I thought you wanted me to use either MICRO or MILLI i.e the fitting one instead of 1000. I see this is the preferred way to show unit conversions. I'll redo in accordance with this pattern. > > > *val2 =3D chan->scan_type.realbits; > > return IIO_VAL_FRACTIONAL_LOG2; > > -- > With Best Regards, > Andy Shevchenko > > --=20 Sincerely, Archit Anant