USB: Fix pointer/int cast in USB devio code
David Howells [Wed, 2 Jul 2008 11:28:55 +0000 (12:28 +0100)]
Fix pointer/int cast in USB devio code, and thus avoid a compiler warning.

A void* data argument passed to bus_find_device() and thence to match_devt()
is used to carry a 32-bit datum.  However, casting directly between a u32 and
a pointer is not permitted - there must be an intermediate cast via (unsigned)
long.

This was introduced by the following patch:

commit 94b1c9fa060ece2c8f080583beb6cc6008e41413
Author: Alan Stern <stern@rowland.harvard.edu>
Date:   Tue Jun 24 14:47:12 2008 -0400

    usbfs: simplify the lookup-by-minor routines

    This patch (as1105) simplifies the lookup-by-minor-number code in
    usbfs.  Instead of passing the minor number to the callback, which
    must then reconstruct the entire dev_t value, the patch passes the
    dev_t value directly.

    Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
    Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/core/devio.c

index 5580c6e..54a350c 100644 (file)
@@ -552,14 +552,15 @@ static int check_ctrlrecip(struct dev_state *ps, unsigned int requesttype,
 
 static int match_devt(struct device *dev, void *data)
 {
-       return (dev->devt == (dev_t) data);
+       return dev->devt == (dev_t) (unsigned long) data;
 }
 
 static struct usb_device *usbdev_lookup_by_devt(dev_t devt)
 {
        struct device *dev;
 
-       dev = bus_find_device(&usb_bus_type, NULL, (void *) devt, match_devt);
+       dev = bus_find_device(&usb_bus_type, NULL,
+                             (void *) (unsigned long) devt, match_devt);
        if (!dev)
                return NULL;
        return container_of(dev, struct usb_device, dev);