On Thu, Apr 14, 2022 at 12:27:23PM -0700, Drew Fustini wrote: > Add documentation for the ti,set-io-isolation DT property on the wkup_m3_ipc > node which tells the wkup_m3_ipc driver to use the wkup_m3 to enable > IO Isolation during low power mode transitions on am43xx platforms. > > Signed-off-by: Dave Gerlach <d-gerlach@xxxxxx> > [dfustini: convert to YAML, make DTS example that passes check] > Signed-off-by: Drew Fustini <dfustini@xxxxxxxxxxxx> > --- > Changes from v2: > - correct indentation of the 'allOf:' block > > Changes from v1: > - correct typo of 'ti,set-io-isolation' property in subject > - make 'ti,set-io-isolation' only valid for 'ti,am4372-wkup-m3-ipc' > > .../bindings/soc/ti/wkup-m3-ipc.yaml | 78 +++++++++++++++++-- > 1 file changed, 73 insertions(+), 5 deletions(-) > > diff --git a/Documentation/devicetree/bindings/soc/ti/wkup-m3-ipc.yaml b/Documentation/devicetree/bindings/soc/ti/wkup-m3-ipc.yaml > index 7f4a75c5fcaa..f0ae86250fe4 100644 > --- a/Documentation/devicetree/bindings/soc/ti/wkup-m3-ipc.yaml > +++ b/Documentation/devicetree/bindings/soc/ti/wkup-m3-ipc.yaml > @@ -24,14 +24,22 @@ description: |+ > A wkup_m3_ipc device node is used to represent the IPC registers within an > SoC. > > - Support for VTT Toggle > - ================================== > + Support for VTT Toggle with GPIO pin > + ==================================== > On some boards like the AM335x EVM-SK and the AM437x GP EVM, a GPIO pin is > connected to the enable pin on the DDR VTT regulator. This allows the > regulator to be disabled upon suspend and enabled upon resume. Please note > that the GPIO pin must be part of the GPIO0 module as only this GPIO module > is in the wakeup power domain. > > + Support for IO Isolation > + ======================== > + On AM437x SoCs, certain pins can be forced into an alternate state when IO > + isolation is activated. Those pins have pad control registers prefixed by > + 'CTRL_CONF_' that contain DS0 (e.g. deep sleep) configuration bits that can > + override the pin's existing bias (pull-up/pull-down) and value (high/low) when > + IO isolation is active. > + > properties: > compatible: > enum: > @@ -63,6 +71,24 @@ properties: > $ref: /schemas/types.yaml#/definitions/uint32 > description: GPIO pin connected to enable pin on VTT regulator > > + ti,set-io-isolation: > + type: boolean > + description: > + If this property is present, then the wkup_m3_ipc driver will instruct > + the CM3 firmware to activate IO isolation when suspending to deep sleep. > + This can be leveraged by a board design to put other devices on the board > + into a low power state. > +allOf: Rob - sorry for the churn. I realize now that there should have been a blank line before 'allOf:'. Should I send a v4 or (if there are not other issues) could that just added when applying? Thank you, Drew
