xref: /freebsd/sys/contrib/device-tree/Bindings/reset/st,sti-picophyreset.txt (revision 22d7dd834bc5cd189810e414701e3ad1e98102e4)
1STMicroelectronics STi family Sysconfig Picophy SoftReset Controller
2=============================================================================
3
4This binding describes a reset controller device that is used to enable and
5disable on-chip PicoPHY USB2 phy(s) using "softreset" control bits found in
6the STi family SoC system configuration registers.
7
8The actual action taken when softreset is asserted is hardware dependent.
9However, when asserted it may not be possible to access the hardware's
10registers and after an assert/deassert sequence the hardware's previous state
11may no longer be valid.
12
13Please refer to Documentation/devicetree/bindings/reset/reset.txt
14for common reset controller binding usage.
15
16Required properties:
17- compatible: Should be "st,stih407-picophyreset"
18- #reset-cells: 1, see below
19
20Example:
21
22	picophyreset: picophyreset-controller {
23		compatible = "st,stih407-picophyreset";
24		#reset-cells = <1>;
25	};
26
27Specifying picophyreset control of devices
28=======================================
29
30Device nodes should specify the reset channel required in their "resets"
31property, containing a phandle to the picophyreset device node and an
32index specifying which channel to use, as described in
33Documentation/devicetree/bindings/reset/reset.txt.
34
35Example:
36
37	usb2_picophy0: usbpicophy@0 {
38		resets = <&picophyreset STIH407_PICOPHY0_RESET>;
39	};
40
41Macro definitions for the supported reset channels can be found in:
42include/dt-bindings/reset/stih407-resets.h
43