Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) What:		/sys/bus/i2c/devices/.../bd9571mwv-regulator.*.auto/backup_mode
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) Date:		Jul 2018
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3) KernelVersion:	4.19
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4) Contact:	Geert Uytterhoeven <geert+renesas@glider.be>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5) Description:	Read/write the current state of DDR Backup Mode, which controls
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) 		if DDR power rails will be kept powered during system suspend.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) 		("on"/"1" = enabled, "off"/"0" = disabled).
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) 		Two types of power switches (or control signals) can be used:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) 		  A. With a momentary power switch (or pulse signal), DDR
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) 		     Backup Mode is enabled by default when available, as the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) 		     PMIC will be configured only during system suspend.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) 		  B. With a toggle power switch (or level signal), the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) 		     following steps must be followed exactly:
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 		       1. Configure PMIC for backup mode, to change the role of
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 			  the accessory power switch from a power switch to a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 			  wake-up switch,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 		       2. Switch accessory power switch off, to prepare for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 			  system suspend, which is a manual step not controlled
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 			  by software,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 		       3. Suspend system,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 		       4. Switch accessory power switch on, to resume the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 			  system.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 		     DDR Backup Mode must be explicitly enabled by the user,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 		     to invoke step 1.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 		See also Documentation/devicetree/bindings/mfd/bd9571mwv.txt.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) Users:		User space applications for embedded boards equipped with a
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 		BD9571MWV PMIC.