On Fri, Dec 30, 2016 at 12:55:27PM +0100, Marek Szyprowski wrote: > Hi Krzysztof, > > On 2016-12-27 16:33, Krzysztof Kozlowski wrote: > > On Tue, Dec 27, 2016 at 11:30:57AM +0100, Marek Szyprowski wrote: > > > On 2016-12-25 20:19, Krzysztof Kozlowski wrote: > > > > On Fri, Dec 23, 2016 at 01:24:47PM +0100, Marek Szyprowski wrote: > > > > > Add support for special property "samsung,off-state", which indicates a special > > > > > state suitable for device's "sleep" state. Its pin values/properties should > > > > > match the configuration in power down mode. It indicates that pin controller > > > > > can notify runtime power management subsystem, that it is ready for runtime > > > > > suspend if its all pins are configured for such state. This in turn might > > > > > allow to turn respective power domain off to reduce power consumption. > > > > > > > > > > Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> > > > > > --- > > > > > Documentation/devicetree/bindings/pinctrl/samsung-pinctrl.txt | 8 ++++++++ > > > > > drivers/pinctrl/samsung/pinctrl-samsung.c | 4 ++++ > > > > > drivers/pinctrl/samsung/pinctrl-samsung.h | 1 + > > > > > 3 files changed, 13 insertions(+) > > > > > > > > > > diff --git a/Documentation/devicetree/bindings/pinctrl/samsung-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/samsung-pinctrl.txt > > > > > index b7bd2e12a269..354eea0e7798 100644 > > > > > --- a/Documentation/devicetree/bindings/pinctrl/samsung-pinctrl.txt > > > > > +++ b/Documentation/devicetree/bindings/pinctrl/samsung-pinctrl.txt > > > > > @@ -105,6 +105,7 @@ Required Properties: > > > > > - samsung,pin-drv: Drive strength configuration. > > > > > - samsung,pin-pud-pdn: Pull up/down configuration in power down mode. > > > > > - samsung,pin-drv-pdn: Drive strength configuration in power down mode. > > > > > + - samsung,off-state: Mark this configuration as suitable for bank power off. > > > > > The values specified by these config properties should be derived from the > > > > > hardware manual and these values are programmed as-is into the pin > > > > > @@ -113,6 +114,13 @@ Required Properties: > > > > > Note: A child should include atleast a pin function selection property or > > > > > pin configuration property (one or more) or both. > > > > > + Note: Special property "samsung,off-state" indicates that this state can > > > > > + be used for device's "sleep" pins state. Its pin values/properties should > > > > > + match the configuration in power down mode. > > > > Why power down values cannot be used for sleep state? Why you need > > > > separate pin control state? If pins values should match power down > > > > configuration, then they could just be added to default state, couldn't > > > > they? > > > Separate sleep state is needed because of the pin control bindings and > > > design. > > > > > > A separate sleep state is required to let pin control client driver (in this > > > case > > > Exynos I2S driver) let to choose when it is okay to switch pads into sleep > > > state and I see no other way to achieve this. > > Maybe the pinctrl API should be extended for this? Doing this in DTS > > just for purpose of passing information between drivers (consumer and > > provider) looks odd. > > Well, I don't know if it is odd or not, but that's how it is used now and I > see > no reason to reinvent wheel. Please check it yourself: > $ git grep \"sleep\" arch/arm/boot/dts | wc -l > 101 These drivers, at least not all of them, are not using the existence of sleep mode configuration as a indication of possible runtime sleep. You are mixing here different ideas. > > > Anyway, you are proposing a new binding so please Cc devicetree mailing > > list and device tree maintainers. > > I'm just using the generic pinctrl bindings, but it might make some sense to > add a note to Exynos i2s driver that a sleep pin control state is needed if > one wants to get power domain to be turned off. The samsung,off-state is a extension of the existing binding, so please Cc the devicetree and maintainers. Why you see a problem in it? Best regards, Krzysztof -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
