From 5697db4a696c41601a1d15c1922150b4dbf5726c Mon Sep 17 00:00:00 2001 From: =?utf8?q?Bj=C3=B8rn=20Mork?= Date: Wed, 2 May 2018 22:22:54 +0200 Subject: [PATCH] qmi_wwan: do not steal interfaces from class drivers MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The USB_DEVICE_INTERFACE_NUMBER matching macro assumes that the { vendorid, productid, interfacenumber } set uniquely identifies one specific function. This has proven to fail for some configurable devices. One example is the Quectel EM06/EP06 where the same interface number can be either QMI or MBIM, without the device ID changing either. Fix by requiring the vendor-specific class for interface number based matching. Functions of other classes can and should use class based matching instead. Fixes: 03304bcb5ec4 ("net: qmi_wwan: use fixed interface number matching") Signed-off-by: Bjørn Mork Signed-off-by: David S. Miller --- drivers/net/usb/qmi_wwan.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/drivers/net/usb/qmi_wwan.c b/drivers/net/usb/qmi_wwan.c index 51c68fc416fa..42565dd33aa6 100644 --- a/drivers/net/usb/qmi_wwan.c +++ b/drivers/net/usb/qmi_wwan.c @@ -1344,6 +1344,18 @@ static int qmi_wwan_probe(struct usb_interface *intf, id->driver_info = (unsigned long)&qmi_wwan_info; } + /* There are devices where the same interface number can be + * configured as different functions. We should only bind to + * vendor specific functions when matching on interface number + */ + if (id->match_flags & USB_DEVICE_ID_MATCH_INT_NUMBER && + desc->bInterfaceClass != USB_CLASS_VENDOR_SPEC) { + dev_dbg(&intf->dev, + "Rejecting interface number match for class %02x\n", + desc->bInterfaceClass); + return -ENODEV; + } + /* Quectel EC20 quirk where we've QMI on interface 4 instead of 0 */ if (quectel_ec20_detected(intf) && desc->bInterfaceNumber == 0) { dev_dbg(&intf->dev, "Quectel EC20 quirk, skipping interface 0\n"); -- 2.30.2