When a new device with a specialised device driver is plugged in, the
new driver will be modprobe()'d but the driver core will attach the
"generic" driver to the device.
After that, nothing will trigger a reprobe when the modprobe()'d device
driver has finished initialising, as the device has the "generic"
driver attached to it.
Trigger a reprobe ourselves when new specialised drivers get
registered.
Fixes: 88b7381a939d
Signed-off-by: Bastien Nocera <hadess@xxxxxxxxxx>
---
Changes since v1:
- Simplified after Alan Stern's comments and some clarifications from
Benjamin Tissoires.
drivers/usb/core/driver.c | 29 +++++++++++++++++++++++++++--
1 file changed, 27 insertions(+), 2 deletions(-)
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c
index f81606c6a35b..44531910637c 100644
--- a/drivers/usb/core/driver.c
+++ b/drivers/usb/core/driver.c
@@ -905,6 +905,25 @@ static int usb_uevent(struct device *dev, struct
kobj_uevent_env *env)
return 0;
}
+static int __usb_bus_reprobe_drivers(struct device *dev, void *data)
+{
+ struct usb_device_driver *udriver = to_usb_device_driver(dev-
>driver);
+ struct usb_device *udev = to_usb_device(dev);
+
+ if (dev->driver) {
+ struct usb_device_driver *udriver =
to_usb_device_driver(dev->driver);
+
+ if (udriver == NULL || udriver == &usb_generic_driver)
{
+ udev->use_generic_driver = false;
+ device_reprobe(dev);
+ }
+ } else {
+ device_reprobe(dev);
+ }
+
+ return 0;
+}
+
/**
* usb_register_device_driver - register a USB device (not interface)
driver
* @new_udriver: USB operations for the device driver
@@ -934,13 +953,19 @@ int usb_register_device_driver(struct
usb_device_driver *new_udriver,
retval = driver_register(&new_udriver->drvwrap.driver);
- if (!retval)
+ if (!retval) {
+ /* Check whether any device could be better served with
+ * this new driver
+ */
+ bus_for_each_dev(&usb_bus_type, NULL, NULL,
+ __usb_bus_reprobe_drivers);
pr_info("%s: registered new device driver %s\n",
usbcore_name, new_udriver->name);
- else
+ } else {
printk(KERN_ERR "%s: error %d registering device "
" driver %s\n",
usbcore_name, retval, new_udriver->name);
+ }
return retval;
}
