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