[PATCH] usb: dwc3-generic: fix CONFIG_DM_REGULATOR-off case

[Jan Kiszka]

From: Jan Kiszka <jan.kiszka at siemens.com>

When DM_REGULATOR is disabled, all calls will return -ENOSYS. Account
for that so that targets like the IOT2050 will work again.

Fixes: de451d5d5b6f ("usb: dwc3-generic: support external vbus regulator")
Signed-off-by: Jan Kiszka <jan.kiszka at siemens.com>
---
 drivers/usb/dwc3/dwc3-generic.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/usb/dwc3/dwc3-generic.c b/drivers/usb/dwc3/dwc3-generic.c
index a9ba315463c..2ab41cbae45 100644
--- a/drivers/usb/dwc3/dwc3-generic.c
+++ b/drivers/usb/dwc3/dwc3-generic.c
@@ -246,12 +246,12 @@ static int dwc3_generic_host_probe(struct udevice *dev)
 		return rc;
 
 	rc = device_get_supply_regulator(dev, "vbus-supply", &priv->vbus_supply);
-	if (rc)
+	if (rc && rc != -ENOSYS)
 		debug("%s: No vbus regulator found: %d\n", dev->name, rc);
 
-	/* Only returns an error if regulator is valid and failed to enable due to a driver issue */
+	/* Does not return an error if regulator is invalid - but does so when DM_REGULATOR is disabled */
 	rc = regulator_set_enable_if_allowed(priv->vbus_supply, true);
-	if (rc)
+	if (rc && rc != -ENOSYS)
 		return rc;
 
 	hccr = (struct xhci_hccr *)priv->gen_priv.base;
-- 
2.43.0