Commit 77419aa4 authored by Bastien Nocera's avatar Bastien Nocera Committed by Greg Kroah-Hartman
Browse files

USB: Fallback to generic driver when specific driver fails 



If ->probe fails for a device specific driver, ask the driver core to
reprobe us, after having flagged the device for the generic driver to be
forced.

Signed-off-by: default avatarBastien Nocera <hadess@hadess.net>
Acked-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/20191016093933.693-6-hadess@hadess.net


Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 88b7381a

drivers/usb/core/driver.c

+4 −1
Original line number Diff line number Diff line
@@ -270,7 +270,10 @@ static int usb_probe_device(struct device *dev) 
		return error;



	error = udriver->probe(udev);

	/* TODO: fallback to generic driver in case of error */

	if (error == -ENODEV && udriver != &usb_generic_driver) {

		udev->use_generic_driver = 1;

		return -EPROBE_DEFER;

	}

	return error;

}

drivers/usb/core/generic.c

+3 −0
Original line number Diff line number Diff line
@@ -213,6 +213,9 @@ static int __check_usb_generic(struct device_driver *drv, void *data) 


static bool usb_generic_driver_match(struct usb_device *udev)

{

	if (udev->use_generic_driver)

		return true;



	/*

	 * If any other driver wants the device, leave the device to this other

	 * driver.

include/linux/usb.h

+1 −0
Original line number Diff line number Diff line
@@ -708,6 +708,7 @@ struct usb_device { 
	unsigned lpm_disable_count;



	u16 hub_delay;

	unsigned use_generic_driver:1;

};

#define	to_usb_device(d) container_of(d, struct usb_device, dev)

CRA Git | Maintained and supported by SUSTech CRA and CCSE