[PATCH 5.10 240/289] usb: dwc3: omap: improve extcon initialization

From: Greg Kroah-Hartman
Date: Mon May 17 2021 - 12:07:19 EST


From: Marcel Hamer <marcel@xxxxxxxxxx>

commit e17b02d4970913233d543c79c9c66e72cac05bdd upstream.

When extcon is used in combination with dwc3, it is assumed that the dwc3
registers are untouched and as such are only configured if VBUS is valid
or ID is tied to ground.

In case VBUS is not valid or ID is floating, the registers are not
configured as such during driver initialization, causing a wrong
default state during boot.

If the registers are not in a default state, because they are for
instance touched by a boot loader, this can cause for a kernel error.

Signed-off-by: Marcel Hamer <marcel@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210427122118.1948340-1-marcel@xxxxxxxxxx
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/dwc3/dwc3-omap.c | 5 +++++
1 file changed, 5 insertions(+)

--- a/drivers/usb/dwc3/dwc3-omap.c
+++ b/drivers/usb/dwc3/dwc3-omap.c
@@ -437,8 +437,13 @@ static int dwc3_omap_extcon_register(str

if (extcon_get_state(edev, EXTCON_USB) == true)
dwc3_omap_set_mailbox(omap, OMAP_DWC3_VBUS_VALID);
+ else
+ dwc3_omap_set_mailbox(omap, OMAP_DWC3_VBUS_OFF);
+
if (extcon_get_state(edev, EXTCON_USB_HOST) == true)
dwc3_omap_set_mailbox(omap, OMAP_DWC3_ID_GROUND);
+ else
+ dwc3_omap_set_mailbox(omap, OMAP_DWC3_ID_FLOAT);

omap->edev = edev;
}