From ab7cd8c76cb47f1bda0ad964d309b4efce81b5e9 Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Tue, 15 Dec 2009 07:47:28 -0800 Subject: [PATCH] Revert "USB: Close usb_find_interface race" This reverts commit a2582bd478c13c574d4c16ef1209d333f2a25935. It turned out to be buggy and broke USB printers from working. Cc: Russ Dill Cc: stable Signed-off-by: Greg Kroah-Hartman --- drivers/usb/core/usb.c | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-) diff --git a/drivers/usb/core/usb.c b/drivers/usb/core/usb.c index 4e2c6df8d3cc..932f68e6ad19 100644 --- a/drivers/usb/core/usb.c +++ b/drivers/usb/core/usb.c @@ -167,17 +167,24 @@ struct usb_host_interface *usb_altnum_to_altsetting( } EXPORT_SYMBOL_GPL(usb_altnum_to_altsetting); +struct find_interface_arg { + int minor; + struct usb_interface *interface; +}; + static int __find_interface(struct device *dev, void *data) { - int *minor = data; + struct find_interface_arg *arg = data; struct usb_interface *intf; if (!is_usb_interface(dev)) return 0; intf = to_usb_interface(dev); - if (intf->minor != -1 && intf->minor == *minor) + if (intf->minor != -1 && intf->minor == arg->minor) { + arg->interface = intf; return 1; + } return 0; } @@ -186,20 +193,21 @@ static int __find_interface(struct device *dev, void *data) * @drv: the driver whose current configuration is considered * @minor: the minor number of the desired device * - * This walks the bus device list and returns a pointer to the interface + * This walks the driver device list and returns a pointer to the interface * with the matching minor. Note, this only works for devices that share the * USB major number. */ struct usb_interface *usb_find_interface(struct usb_driver *drv, int minor) { - struct device *dev; - - dev = bus_find_device(&usb_bus_type, NULL, &minor, __find_interface); - - /* Drop reference count from bus_find_device */ - put_device(dev); + struct find_interface_arg argb; + int retval; - return dev ? to_usb_interface(dev) : NULL; + argb.minor = minor; + argb.interface = NULL; + /* eat the error, it will be in argb.interface */ + retval = driver_for_each_device(&drv->drvwrap.driver, NULL, &argb, + __find_interface); + return argb.interface; } EXPORT_SYMBOL_GPL(usb_find_interface); -- 2.20.1