4 files changed, 27 insertions, 6 deletions

diff --git a/Documentation/ABI/testing/sysfs-bus-usb b/Documentation/ABI/testing/sysfs-bus-usb
index 1430f584b266..614d451cee41 100644
--- a/Documentation/ABI/testing/sysfs-bus-usb
+++ b/Documentation/ABI/testing/sysfs-bus-usb
@@ -50,13 +50,19 @@ Description:
                 This may allow the driver to support more hardware than
                 was included in the driver's static device ID support
                 table at compile time. The format for the device ID is:
-                idVendor idProduct bInterfaceClass.
+                idVendor idProduct bInterfaceClass RefIdVendor RefIdProduct
                 The vendor ID and device ID fields are required, the
-                interface class is optional.
+                rest is optional. The Ref* tuple can be used to tell the
+                driver to use the same driver_data for the new device as
+                it is used for the reference device.
                 Upon successfully adding an ID, the driver will probe
                 for the device and attempt to bind to it.  For example:
                 # echo "8086 10f5" > /sys/bus/usb/drivers/foo/new_id
 
+                Here add a new device (0458:7045) using driver_data from
+                an already supported device (0458:704c):
+                # echo "0458 7045 0 0458 704c" > /sys/bus/usb/drivers/foo/new_id
+
                 Reading from this file will list all dynamically added
                 device IDs in the same format, with one entry per
                 line. For example:
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index 574f5a04c92d..9b29e5c94be7 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -37,6 +37,7 @@
  * and cause the driver to probe for all devices again.
  */
 ssize_t usb_store_new_id(struct usb_dynids *dynids,
+                         const struct usb_device_id *id_table,
                          struct device_driver *driver,
                          const char *buf, size_t count)
 {
@@ -44,11 +45,12 @@ ssize_t usb_store_new_id(struct usb_dynids *dynids,
         u32 idVendor = 0;
         u32 idProduct = 0;
         unsigned int bInterfaceClass = 0;
+        u32 refVendor, refProduct;
         int fields = 0;
         int retval = 0;
 
-        fields = sscanf(buf, "%x %x %x", &idVendor, &idProduct,
-                                        &bInterfaceClass);
+        fields = sscanf(buf, "%x %x %x %x %x", &idVendor, &idProduct,
+                        &bInterfaceClass, &refVendor, &refProduct);
         if (fields < 2)
                 return -EINVAL;
 
@@ -68,6 +70,16 @@ ssize_t usb_store_new_id(struct usb_dynids *dynids,
                 dynid->id.match_flags |= USB_DEVICE_ID_MATCH_INT_CLASS;
         }
 
+        if (fields > 4) {
+                const struct usb_device_id *id = id_table;
+
+                for (; id->match_flags; id++)
+                        if (id->idVendor == refVendor && id->idProduct == refProduct) {
+                                dynid->id.driver_info = id->driver_info;
+                                break;
+                        }
+        }
+
         spin_lock(&dynids->lock);
         list_add_tail(&dynid->node, &dynids->list);
         spin_unlock(&dynids->lock);
@@ -109,7 +121,7 @@ static ssize_t new_id_store(struct device_driver *driver,
 {
         struct usb_driver *usb_drv = to_usb_driver(driver);
 
-        return usb_store_new_id(&usb_drv->dynids, driver, buf, count);
+        return usb_store_new_id(&usb_drv->dynids, usb_drv->id_table, driver, buf, count);
 }
 static DRIVER_ATTR_RW(new_id);
 
diff --git a/drivers/usb/serial/bus.c b/drivers/usb/serial/bus.c
index 6335490d5760..35a2373cde67 100644
--- a/drivers/usb/serial/bus.c
+++ b/drivers/usb/serial/bus.c
@@ -125,10 +125,12 @@ static ssize_t new_id_store(struct device_driver *driver,
                             const char *buf, size_t count)
 {
         struct usb_serial_driver *usb_drv = to_usb_serial_driver(driver);
-        ssize_t retval = usb_store_new_id(&usb_drv->dynids, driver, buf, count);
+        ssize_t retval = usb_store_new_id(&usb_drv->dynids, usb_drv->id_table,
+                                         driver, buf, count);
 
         if (retval >= 0 && usb_drv->usb_driver != NULL)
                 retval = usb_store_new_id(&usb_drv->usb_driver->dynids,
+                                          usb_drv->usb_driver->id_table,
                                           &usb_drv->usb_driver->drvwrap.driver,
                                           buf, count);
         return retval;
diff --git a/include/linux/usb.h b/include/linux/usb.h
index 512ab162832c..c716da18c668 100644
--- a/include/linux/usb.h
+++ b/include/linux/usb.h
@@ -965,6 +965,7 @@ struct usb_dynid {
 };
 
 extern ssize_t usb_store_new_id(struct usb_dynids *dynids,
+                                const struct usb_device_id *id_table,
                                 struct device_driver *driver,
                                 const char *buf, size_t count);