[mirror_ubuntu-bionic-kernel.git] / Documentation / devicetree / bindings / reset / st,sti-softreset.txt

STMicroelectronics STi family Sysconfig Peripheral SoftReset 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
"softreset" control bits found in the STi family SoC system configuration
registers.

The actual action taken when softreset 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,stih407-softreset";
- #reset-cells: 1, see below

example:

	softreset: softreset-controller {
		#reset-cells = <1>;
		compatible = "st,stih407-softreset";
	};


Specifying softreset control of devices
=======================================

Device nodes should specify the reset channel required in their "resets"
property, containing a phandle to the softreset device node and an
index specifying which channel to use, as described in reset.txt

example:

	ethernet0{
		resets			= <&softreset STIH415_ETH0_SOFTRESET>;
	};

Macro definitions for the supported reset channels can be found in:

include/dt-bindings/reset/stih407-resets.h
Commit	Line	Data
fc58fcf6 SK	1	STMicroelectronics STi family Sysconfig Peripheral SoftReset Controller
	2	=============================================================================
	3
	4	This binding describes a reset controller device that is used to enable and
	5	disable on-chip peripheral controllers such as USB and SATA, using
	6	"softreset" control bits found in the STi family SoC system configuration
	7	registers.
	8
	9	The actual action taken when softreset is asserted is hardware dependent.
	10	However, when asserted it may not be possible to access the hardware's
	11	registers and after an assert/deassert sequence the hardware's previous state
	12	may no longer be valid.
	13
	14	Please refer to reset.txt in this directory for common reset
	15	controller binding usage.
	16
	17	Required properties:
4721ca73	18	- compatible: Should be st,stih407-softreset";
fc58fcf6 SK	19	- #reset-cells: 1, see below
	20
	21	example:
	22
	23	softreset: softreset-controller {
	24	#reset-cells = <1>;
4721ca73	25	compatible = "st,stih407-softreset";
fc58fcf6 SK	26	};
	27
	28
	29	Specifying softreset control of devices
	30	=======================================
	31
	32	Device nodes should specify the reset channel required in their "resets"
	33	property, containing a phandle to the softreset device node and an
	34	index specifying which channel to use, as described in reset.txt
	35
	36	example:
	37
	38	ethernet0{
	39	resets = <&softreset STIH415_ETH0_SOFTRESET>;
	40	};
	41
	42	Macro definitions for the supported reset channels can be found in:
	43
4721ca73	44	include/dt-bindings/reset/stih407-resets.h