[PATCH] usb-storage: use usb_reset_composite_device
This patch (as701) modifies usb-storage to take advantage of the new
usb_reset_composite_device() API. Now we will be able to safely request
port resets even if other drivers are bound to a mass-storage device.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/usb/storage/transport.c b/drivers/usb/storage/transport.c
index 038f458..19b25c5 100644
--- a/drivers/usb/storage/transport.c
+++ b/drivers/usb/storage/transport.c
@@ -703,16 +703,19 @@
* device reset. */
Handle_Errors:
- /* Let the SCSI layer know we are doing a reset, set the
- * RESETTING bit, and clear the ABORTING bit so that the reset
- * may proceed. */
+ /* Set the RESETTING bit, and clear the ABORTING bit so that
+ * the reset may proceed. */
scsi_lock(us_to_host(us));
- usb_stor_report_bus_reset(us);
set_bit(US_FLIDX_RESETTING, &us->flags);
clear_bit(US_FLIDX_ABORTING, &us->flags);
scsi_unlock(us_to_host(us));
+ /* We must release the device lock because the pre_reset routine
+ * will want to acquire it. */
+ mutex_unlock(&us->dev_mutex);
result = usb_stor_port_reset(us);
+ mutex_lock(&us->dev_mutex);
+
if (result < 0) {
scsi_lock(us_to_host(us));
usb_stor_report_device_reset(us);
@@ -1196,31 +1199,30 @@
0, us->ifnum, NULL, 0);
}
-/* Issue a USB port reset to the device. But don't do anything if
- * there's more than one interface in the device, so that other users
- * are not affected. */
+/* Issue a USB port reset to the device. The caller must not hold
+ * us->dev_mutex.
+ */
int usb_stor_port_reset(struct us_data *us)
{
- int result, rc;
+ int result, rc_lock;
- if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
- result = -EIO;
- US_DEBUGP("No reset during disconnect\n");
- } else if (us->pusb_dev->actconfig->desc.bNumInterfaces != 1) {
- result = -EBUSY;
- US_DEBUGP("Refusing to reset a multi-interface device\n");
- } else {
- result = rc =
- usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf);
- if (result < 0) {
- US_DEBUGP("unable to lock device for reset: %d\n",
- result);
+ result = rc_lock =
+ usb_lock_device_for_reset(us->pusb_dev, us->pusb_intf);
+ if (result < 0)
+ US_DEBUGP("unable to lock device for reset: %d\n", result);
+ else {
+ /* Were we disconnected while waiting for the lock? */
+ if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
+ result = -EIO;
+ US_DEBUGP("No reset during disconnect\n");
} else {
- result = usb_reset_device(us->pusb_dev);
- if (rc)
- usb_unlock_device(us->pusb_dev);
- US_DEBUGP("usb_reset_device returns %d\n", result);
+ result = usb_reset_composite_device(
+ us->pusb_dev, us->pusb_intf);
+ US_DEBUGP("usb_reset_composite_device returns %d\n",
+ result);
}
+ if (rc_lock)
+ usb_unlock_device(us->pusb_dev);
}
return result;
}