Thanks Mark, On Mon, 2019-11-18 at 16:20 +0000, Mark Brown wrote: > On Mon, Nov 18, 2019 at 08:57:57AM +0200, Matti Vaittinen wrote: > > > +static int ramp_delay_supported(struct regulator_dev *rdev) > > +{ > > + switch (rdev->desc->id) { > > + case BD71828_BUCK1: > > + case BD71828_BUCK2: > > + case BD71828_BUCK6: > > + case BD71828_BUCK7: > > + return 1; > > + default: > > + break; > > + } > > + return 0; > > +} > > + > > +static int bd71828_set_ramp_delay(struct regulator_dev *rdev, int > > ramp_delay) > > +{ > > + unsigned int val; > > + > > + if (!ramp_delay_supported(rdev)) { > > + dev_err(&rdev->dev, "%s: can't set ramp-delay\n", > > + rdev->desc->name); > > + return -EINVAL; > > Rather than doing this it's better to just not provide the operation > for > devices that don't support it, that makes the handling in the core > easier. Makes sense. I'll change this in next version. Br, Matti Vaittinen