linux-imx

MLK-13125 usb: phy: phy-mxs-usb: enable weak 1p1 regulator for imx6ul during suspend

For imx6ul PHY, when the system enters suspend, its 1p1 is off by default,
that may cause the PHY get inaccurate USB DP/DM value. If the USB wakeup
is enabled at this time, the unexpected wakeup may occur when the system
enters suspend.

In this patch, when the vbus is there, we enable weak 1p1 during the PHY
suspend API, in that case, the USB DP/DM will be accurate for USB PHY,
then unexpected usb wakeup will not be occurred, especially for the USB
charger is connected scenario. The user needs to enable PHY wakeup for
USB wakeup function using below setting.

echo enabled > /sys/devices/platform/soc/2000000.aips-bus/20c9000.usbphy
/power/wakeup

Cc: Shaojun Wang <shaojun.wang@nxp.com>
Cc: Anson Huang <anson.huang@nxp.com>
Signed-off-by: Peter Chen <peter.chen@nxp.com>