Document Wakeup M3 IPC property that indicates a GPIO pin is connected
to the enable pin on DDR VTT regulator and can be toggled during low
power mode transitions.
Signed-off-by: Dave Gerlach <d-gerlach@ti.com>
[dfustini: converted to YAML, removed unnecessary "ti,needs-vtt-toggle"]
Signed-off-by: Drew Fustini <dfustini@baylibre.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220409211215.2529387-2-dfustini@baylibre.com
A wkup_m3_ipc device node is used to represent the IPC registers within an
SoC.
+ Support for VTT Toggle
+ ==================================
+ 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.
+
properties:
compatible:
enum:
mbox_wkupm3 child node.
maxItems: 1
+ ti,vtt-gpio-pin:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: GPIO pin connected to enable pin on VTT regulator
+
required:
- compatible
- reg
interrupts = <78>;
ti,rproc = <&wkup_m3>;
mboxes = <&mailbox &mbox_wkupm3>;
+ ti,vtt-gpio-pin = <7>;
};
};
...