[PATCH] usb: misc: onboard_usb_hub: Don't defer probing for 'incomplete' DT nodes

[Matthias Kaehlcke <mka@chromium.org>]

Some boards have device tree nodes for USB hubs supported by the
onboard_usb_hub driver, but the nodes don't have all properties
needed for the driver to work properly (which is not necessarily
an error in the DT). Currently _find_onboard_hub() returns
-EPROBE_DEFER in such cases, which results in an unusable USB hub,
since successive probes fail in the same way. Use the absence of
the "vdd" supply as an indicator of such 'incomplete' DT nodes
and return -ENODEV.

Fixes: 8bc063641ceb ("usb: misc: Add onboard_usb_hub driver")
Reported-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Matthias Kaehlcke <mka@chromium.org>
---

 drivers/usb/misc/onboard_usb_hub.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/usb/misc/onboard_usb_hub.c b/drivers/usb/misc/onboard_usb_hub.c
index d63c63942af1..2968da515016 100644
--- a/drivers/usb/misc/onboard_usb_hub.c
+++ b/drivers/usb/misc/onboard_usb_hub.c
@@ -363,6 +363,15 @@ static struct onboard_hub *_find_onboard_hub(struct device *dev)
 	hub = dev_get_drvdata(&pdev->dev);
 	put_device(&pdev->dev);
 
+	/*
+	 * Some boards have device tree nodes for USB hubs supported by this
+	 * driver, but the nodes don't have all properties needed for the driver
+	 * to work properly. Use the absence of the "vdd" supply as an indicator
+	 * of such nodes.
+	 */
+	if (!of_get_property(pdev->dev.of_node, "vdd", NULL))
+		return ERR_PTR(-ENODEV);
+
 	/*
 	 * The presence of drvdata ('hub') indicates that the platform driver
 	 * finished probing. This handles the case where (conceivably) we could
-- 
2.39.0.314.g84b9a713c41-goog