tjh.dev
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1STMicroelectronics STi family Sysconfig Peripheral Powerdown Reset Controller
2=============================================================================
3
4This binding describes a reset controller device that is used to enable and
5disable on-chip peripheral controllers such as USB and SATA, using
6"powerdown" control bits found in the STi family SoC system configuration
7registers. These have been grouped together into a single reset controller
8device for convenience.
9
10The actual action taken when powerdown is asserted is hardware dependent.
11However, when asserted it may not be possible to access the hardware's
12registers and after an assert/deassert sequence the hardware's previous state
13may no longer be valid.
14
15Please refer to reset.txt in this directory for common reset
16controller binding usage.
17
18Required properties:
19- compatible: Should be "st,stih407-powerdown"
20- #reset-cells: 1, see below
21
22example:
23
24 powerdown: powerdown-controller {
25 compatible = "st,stih407-powerdown";
26 #reset-cells = <1>;
27 };
28
29
30Specifying powerdown control of devices
31=======================================
32
33Device nodes should specify the reset channel required in their "resets"
34property, containing a phandle to the powerdown device node and an
35index specifying which channel to use, as described in reset.txt
36
37example:
38
39 st_dwc3: dwc3@8f94000 {
40 resets = <&powerdown STIH407_USB3_POWERDOWN>,
41 };
42
43Macro definitions for the supported reset channels can be found in:
44
45include/dt-bindings/reset/stih407-resets.h