st,sti-powerdown.txt 1.6 KB

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  1. STMicroelectronics STi family Sysconfig Peripheral Powerdown Reset Controller
  2. =============================================================================
  3. This binding describes a reset controller device that is used to enable and
  4. disable on-chip peripheral controllers such as USB and SATA, using
  5. "powerdown" control bits found in the STi family SoC system configuration
  6. registers. These have been grouped together into a single reset controller
  7. device for convenience.
  8. The actual action taken when powerdown is asserted is hardware dependent.
  9. However, when asserted it may not be possible to access the hardware's
  10. registers and after an assert/deassert sequence the hardware's previous state
  11. may no longer be valid.
  12. Please refer to reset.txt in this directory for common reset
  13. controller binding usage.
  14. Required properties:
  15. - compatible: Should be "st,<chip>-powerdown"
  16. ex: "st,stih415-powerdown", "st,stih416-powerdown"
  17. - #reset-cells: 1, see below
  18. example:
  19. powerdown: powerdown-controller {
  20. #reset-cells = <1>;
  21. compatible = "st,stih415-powerdown";
  22. };
  23. Specifying powerdown control of devices
  24. =======================================
  25. Device nodes should specify the reset channel required in their "resets"
  26. property, containing a phandle to the powerdown device node and an
  27. index specifying which channel to use, as described in reset.txt
  28. example:
  29. usb1: usb@fe200000 {
  30. resets = <&powerdown STIH41X_USB1_POWERDOWN>;
  31. };
  32. Macro definitions for the supported reset channels can be found in:
  33. include/dt-bindings/reset/stih415-resets.h
  34. include/dt-bindings/reset/stih416-resets.h