On Thursday 06 April 2017 06:33 PM, Thierry Reding wrote:
* PGP Signed by an unknown key
On Thu, Apr 06, 2017 at 09:57:09AM +0100, Jon Hunter wrote:
On 05/04/17 15:13, Laxman Dewangan wrote:
+state of the system. The configuration of pin is provided via the pinctrl
+DT node as detailed in the pinctrl DT binding document
+ Documentation/devicetree/bindings/pinctrl/pinctrl-bindings.txt
+
+The PWM node will have following optional properties.
+pinctrl-names: Pin state names. Must be "suspend" and "resume".
Why not just use the pre-defined names here? There is a pre-defined name
for "default", "idle" and "sleep" and then you can use the following
APIs and avoid the lookup of the state ...
pinctrl_pm_select_default_state()
pinctrl_pm_select_idle_state()
pinctrl_pm_select_sleep_state()
Note for i2c [0][1], I used "default" as the active/on state (which I
know is not that descriptive) and then used 'idle' as the suspended
state. This way we don't need any custom names.
Agreed, I think that's how these states are meant to be used.
I did quick grep for the pinctrl_pm_select_* functions in the code tree
and found usage of these APIs in some of the places.
I am taking the reference of i2c-st, i2c-nomadic and
extcon/extcon-usb-gpio.c drivers and from this the interpretation is
default state: When interface active and transfer need to be done in IO
interface.
idle state: Active state of the system but interface is not active, put
in non-active state of the interface.
sleep state: When system entering into suspend and IO interface is going
to be inactive.
So in PWM case, we will need the "default" and "sleep" state.
In suspend(), set the "sleep" state and in resume, set the "default" state.
+ Linus W as I refereed his st/nomadik driver for reference.
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