diff options
author | Bastien Nocera | 2020-08-18 13:04:45 +0200 |
---|---|---|
committer | Greg Kroah-Hartman | 2020-08-18 13:09:31 +0200 |
commit | d5643d2249b279077427b2c2b2ffae9b70c95b0b (patch) | |
tree | c46c848efde4943fe5629a6ca3bd5aad6ab8908d /drivers/usb/core | |
parent | adb6e6ac20eedcf1dce19dc75b224e63c0828ea1 (diff) |
USB: Fix device driver race
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 ("USB: Select better matching USB drivers when available")
Signed-off-by: Bastien Nocera <hadess@hadess.net>
Cc: stable <stable@vger.kernel.org>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20200818110445.509668-3-hadess@hadess.net
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/core')
-rw-r--r-- | drivers/usb/core/driver.c | 40 |
1 files changed, 38 insertions, 2 deletions
diff --git a/drivers/usb/core/driver.c b/drivers/usb/core/driver.c index f81606c6a35b..7e73e989645b 100644 --- a/drivers/usb/core/driver.c +++ b/drivers/usb/core/driver.c @@ -905,6 +905,35 @@ static int usb_uevent(struct device *dev, struct kobj_uevent_env *env) return 0; } +static bool is_dev_usb_generic_driver(struct device *dev) +{ + struct usb_device_driver *udd = dev->driver ? + to_usb_device_driver(dev->driver) : NULL; + + return udd == &usb_generic_driver; +} + +static int __usb_bus_reprobe_drivers(struct device *dev, void *data) +{ + struct usb_device_driver *new_udriver = data; + struct usb_device *udev; + int ret; + + if (!is_dev_usb_generic_driver(dev)) + return 0; + + udev = to_usb_device(dev); + if (usb_device_match_id(udev, new_udriver->id_table) == NULL && + (!new_udriver->match || new_udriver->match(udev) != 0)) + return 0; + + ret = device_reprobe(dev); + if (ret && ret != -EPROBE_DEFER) + dev_err(dev, "Failed to reprobe device (error %d)\n", ret); + + return 0; +} + /** * usb_register_device_driver - register a USB device (not interface) driver * @new_udriver: USB operations for the device driver @@ -934,13 +963,20 @@ int usb_register_device_driver(struct usb_device_driver *new_udriver, retval = driver_register(&new_udriver->drvwrap.driver); - if (!retval) + if (!retval) { pr_info("%s: registered new device driver %s\n", usbcore_name, new_udriver->name); - else + /* + * Check whether any device could be better served with + * this new driver + */ + bus_for_each_dev(&usb_bus_type, NULL, new_udriver, + __usb_bus_reprobe_drivers); + } else { printk(KERN_ERR "%s: error %d registering device " " driver %s\n", usbcore_name, retval, new_udriver->name); + } return retval; } |