[PATCH 2/2] ARM: dts: exynos4412-trats: Add suspend configuration for max77686 regulators
Krzysztof Kozlowski
k.kozlowski at samsung.com
Tue Oct 21 03:14:36 PDT 2014
On wto, 2014-10-21 at 12:00 +0200, Javier Martinez Canillas wrote:
> Hello Krzysztof,
>
> On 10/21/2014 11:23 AM, Krzysztof Kozlowski wrote:
> >> >
> >> > ldo9_reg: ldo9 {
> >> > @@ -295,7 +311,9 @@
> >> > regulator-name = "CAM_ISP_MIPI_1.2V";
> >> > regulator-min-microvolt = <1200000>;
> >> > regulator-max-microvolt = <1200000>;
> >> > - regulator-mem-idle;
> >> > + regulator-state-mem {
> >> > + regulator-on-in-suspend;
> >>
> >> CAM_ISP_MIPI_1.2V is used for camera, I think this regulator should turn off in suspend state
> >> because camear could not be used in suspend state.
> >
> > LDO9 does not support off in suspend mode controlled by PWRREQ. It
> > supports only switching to low power mode if PWRREQ level goes low.
> >
> > Thus the driver does not provide set_suspend_enable or
> > set_suspend_disable for LDO0. Do you want to add such function to the
> > max77686 driver which will explicitly disable the regulator (write 0x0
> > to control reg)?
> >
> >
>
> I think for those regulators you can just use regulator_disable_regmap()
> as the .set_suspend_disable function handler?
Sure... but this does not solve the philosophical problem - this is not
a special suspend configuration. It is disabling the regulator manually,
from regulator core code. Instead probably the camera driver should
disable the regulator in suspend callback.
Another point - I think none of other regulators do this way.
Best regards,
Krzysztof
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