USB: serial: option: add two-endpoints device-id flag

Allow matching on interfaces having two endpoints by adding a new
device-id flag.

This allows for the handling of devices whose interface numbers can
change (e.g. Quectel EP06) to be contained in the device-id table.

Tested-by: Kristian Evensen <kristian.evensen@gmail.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <johan@kernel.org>

1 files changed, 7 insertions, 10 deletions

diff --git a/drivers/usb/serial/option.c b/drivers/usb/serial/option.c
index 382feafbd127..e72ad9f81c73 100644
--- a/drivers/usb/serial/option.c
+++ b/drivers/usb/serial/option.c
@@ -561,6 +561,9 @@ static void option_instat_callback(struct urb *urb);
 /* Interface is reserved */
 #define RSVD(ifnum)     ((BIT(ifnum) & 0xff) << 0)
 
+/* Interface must have two endpoints */
+#define NUMEP2          BIT(16)
+
 
 static const struct usb_device_id option_ids[] = {
         { USB_DEVICE(OPTION_VENDOR_ID, OPTION_PRODUCT_COLT) },
@@ -1082,7 +1085,7 @@ static const struct usb_device_id option_ids[] = {
         { USB_DEVICE(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_BG96),
           .driver_info = RSVD(4) },
         { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EP06, 0xff, 0xff, 0xff),
-          .driver_info = RSVD(1) | RSVD(2) | RSVD(3) | RSVD(4) },
+          .driver_info = RSVD(1) | RSVD(2) | RSVD(3) | RSVD(4) | NUMEP2 },
         { USB_DEVICE_AND_INTERFACE_INFO(QUECTEL_VENDOR_ID, QUECTEL_PRODUCT_EP06, 0xff, 0, 0) },
         { USB_DEVICE(CMOTECH_VENDOR_ID, CMOTECH_PRODUCT_6001) },
         { USB_DEVICE(CMOTECH_VENDOR_ID, CMOTECH_PRODUCT_CMU_300) },
@@ -1986,7 +1989,6 @@ static int option_probe(struct usb_serial *serial,
 {
         struct usb_interface_descriptor *iface_desc =
                                 &serial->interface->cur_altsetting->desc;
-        struct usb_device_descriptor *dev_desc = &serial->dev->descriptor;
         unsigned long device_flags = id->driver_info;
 
         /* Never bind to the CD-Rom emulation interface */
@@ -2002,16 +2004,11 @@ static int option_probe(struct usb_serial *serial,
                 return -ENODEV;
 
         /*
-         * Don't bind to the QMI device of the Quectel EP06/EG06/EM06. Class,
-         * subclass and protocol is 0xff for both the diagnostic port and the
-         * QMI interface, but the diagnostic port only has two endpoints (QMI
-         * has three).
+         * Allow matching on bNumEndpoints for devices whose interface numbers
+         * can change (e.g. Quectel EP06).
          */
-        if (dev_desc->idVendor == cpu_to_le16(QUECTEL_VENDOR_ID) &&
-            dev_desc->idProduct == cpu_to_le16(QUECTEL_PRODUCT_EP06) &&
-            iface_desc->bInterfaceSubClass && iface_desc->bNumEndpoints == 3) {
+        if (device_flags & NUMEP2 && iface_desc->bNumEndpoints != 2)
                 return -ENODEV;
-        }
 
         /* Store the device flags so we can use them during attach. */
         usb_set_serial_data(serial, (void *)device_flags);