[PATCH v2] usb: core: verify devicetree nodes for disabled interfaces

From: Marek Szyprowski
Date: Wed May 08 2019 - 06:45:47 EST


Commit 01fdf179f4b0 ("usb: core: skip interfaces disabled in devicetree")
add support for disabling given USB device interface by adding nodes to
the USB host controller device. The mentioned commit however identifies
the given USB interface node only by the 'reg' property in the host
controller children nodes and then checks for their the 'status'. The USB
device interface nodes however also has to have a 'compatible' property as
described in Documentation/devicetree/bindings/usb/usb-device.txt. This is
important, because USB host controller might have child-nodes for other
purposes. For example, Exynos EHCI and OHCI drivers already define
child-nodes for each physical root hub port and assigns respective PHY
controller and parameters for them. This conflicts with the proposed
approach and verifying for the presence of the compatible property fixes
this issue without changing the bindings and the way the PHY controllers
are handled by Exynos EHCI/OHCI drivers.

Reported-by: Markus Reichl <m.reichl@xxxxxxxxxxxxx>
Fixes: 01fdf179f4b0 ("usb: core: skip interfaces disabled in devicetree")
Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>
---
drivers/usb/core/message.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/drivers/usb/core/message.c b/drivers/usb/core/message.c
index e844bb7b5676..6f7d047392bd 100644
--- a/drivers/usb/core/message.c
+++ b/drivers/usb/core/message.c
@@ -2009,6 +2009,7 @@ int usb_set_configuration(struct usb_device *dev, int configuration)
struct usb_interface *intf = cp->interface[i];

if (intf->dev.of_node &&
+ of_find_property(intf->dev.of_node, "compatible", NULL) &&
!of_device_is_available(intf->dev.of_node)) {
dev_info(&dev->dev, "skipping disabled interface %d\n",
intf->cur_altsetting->desc.bInterfaceNumber);
--
2.17.1