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