Hi, On Mon, Sep 19, 2016 at 1:44 AM, Andy Yan <andy.yan at rock-chips.com> wrote: > The current rk3066a based boards(Rayeager, Bqcurie2, Marsboard) use > pwm modulate vdd_logic voltage, but the pwm is default disabled and > the pwm pin acts as a gpio before pwm regulator probed, so the pwm > regulator driver will get a zero dutycycle at probe time, so change > the initial dutycycle to zero to match pwm_regulator_init_state check. > > Signed-off-by: Andy Yan <andy.yan at rock-chips.com> > > --- > > arch/arm/boot/dts/rk3066a-bqcurie2.dts | 2 +- > arch/arm/boot/dts/rk3066a-marsboard.dts | 2 +- > arch/arm/boot/dts/rk3066a-rayeager.dts | 2 +- > 3 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/arch/arm/boot/dts/rk3066a-bqcurie2.dts b/arch/arm/boot/dts/rk3066a-bqcurie2.dts > index bc674ee..618450d 100644 > --- a/arch/arm/boot/dts/rk3066a-bqcurie2.dts > +++ b/arch/arm/boot/dts/rk3066a-bqcurie2.dts > @@ -61,7 +61,7 @@ > regulator-min-microvolt = <1200000>; > regulator-max-microvolt = <1200000>; > regulator-always-on; > - voltage-table = <1000000 100>, > + voltage-table = <1000000 0>, In my opinion this isn't quite the right answer. I think that you should add a new property describing the voltage in the case that the pin is an input and you should fill that property in, like: voltage-when-input = <1000000>; Once you have this property you should ideally be able to read whether the pin is currently configured as an input or as a special function at bootup. Note that I don't actually know if this is possible with the current pinctrl API, but it does seem like the ideal way to do it since it means you'll work even if the BIOS changes (AKA: if the BIOS leaves the pin as an input you can keep the voltage the same and if the BIOS leaves the pin as PWM you can keep the voltage the same). It's also possible that you could just add a property that says "init to a certain value at bootup no matter what the BIOS left it as". As long as that voltage is the maximum (and you'll lower it later) this ought to be safe and you shouldn't risk temporarily undervolting things. Note that, if you haven't already done so, you almost certainly want to make sure your pinctrl species an "init" state in addition to a "default" state. See <https://patchwork.kernel.org/patch/7454311/>. -Doug
