[PATCH] USB Storage: port reset on transport error

[linux-2.6-block.git] / drivers / usb / storage / transport.c

diff --git a/drivers/usb/storage/transport.c b/drivers/usb/storage/transport.c
index 419afb2216b94edb42f3efc6019742986926e4ce..e6b1c6cf07f24a66eea868df9730e0baac53f15b 100644 (file)
--- a/drivers/usb/storage/transport.c
+++ b/drivers/usb/storage/transport.c
@@ -541,15 +541,15 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
         */
        if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
                US_DEBUGP("-- command was aborted\n");
-               goto Handle_Abort;
+               srb->result = DID_ABORT << 16;
+               goto Handle_Errors;
        }
 
        /* if there is a transport error, reset and don't auto-sense */
        if (result == USB_STOR_TRANSPORT_ERROR) {
                US_DEBUGP("-- transport indicates error, resetting\n");
-               us->transport_reset(us);
                srb->result = DID_ERROR << 16;
-               return;
+               goto Handle_Errors;
        }
 
        /* if the transport provided its own sense data, don't auto-sense */
@@ -669,7 +669,8 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
 
                if (test_bit(US_FLIDX_TIMED_OUT, &us->flags)) {
                        US_DEBUGP("-- auto-sense aborted\n");
-                       goto Handle_Abort;
+                       srb->result = DID_ABORT << 16;
+                       goto Handle_Errors;
                }
                if (temp_result != USB_STOR_TRANSPORT_GOOD) {
                        US_DEBUGP("-- auto-sense failure\n");
@@ -678,9 +679,9 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
                         * multi-target device, since failure of an
                         * auto-sense is perfectly valid
                         */
-                       if (!(us->flags & US_FL_SCM_MULT_TARG))
-                               us->transport_reset(us);
                        srb->result = DID_ERROR << 16;
+                       if (!(us->flags & US_FL_SCM_MULT_TARG))
+                               goto Handle_Errors;
                        return;
                }
 
@@ -721,12 +722,28 @@ void usb_stor_invoke_transport(struct scsi_cmnd *srb, struct us_data *us)
 
        return;
 
-       /* abort processing: the bulk-only transport requires a reset
-        * following an abort */
-  Handle_Abort:
-       srb->result = DID_ABORT << 16;
-       if (us->protocol == US_PR_BULK)
+       /* Error and abort processing: try to resynchronize with the device
+        * by issuing a port reset.  If that fails, try a class-specific
+        * 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. */
+       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));
+
+       result = usb_stor_port_reset(us);
+       if (result < 0) {
+               scsi_lock(us_to_host(us));
+               usb_stor_report_device_reset(us);
+               scsi_unlock(us_to_host(us));
                us->transport_reset(us);
+       }
+       clear_bit(US_FLIDX_RESETTING, &us->flags);
 }
 
 /* Stop the current URB transfer */
@@ -1134,24 +1151,18 @@ static int usb_stor_reset_common(struct us_data *us,
 {
        int result;
        int result2;
-       int rc = FAILED;
 
-       /* 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.
-        */
-       scsi_lock(us_to_host(us));
-       usb_stor_report_device_reset(us);
-       set_bit(US_FLIDX_RESETTING, &us->flags);
-       clear_bit(US_FLIDX_ABORTING, &us->flags);
-       scsi_unlock(us_to_host(us));
+       if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
+               US_DEBUGP("No reset during disconnect\n");
+               return -EIO;
+       }
 
        result = usb_stor_control_msg(us, us->send_ctrl_pipe,
                        request, requesttype, value, index, data, size,
                        5*HZ);
        if (result < 0) {
                US_DEBUGP("Soft reset failed: %d\n", result);
-               goto Done;
+               return result;
        }
 
        /* Give the device some time to recover from the reset,
@@ -1161,7 +1172,7 @@ static int usb_stor_reset_common(struct us_data *us,
                        HZ*6);
        if (test_bit(US_FLIDX_DISCONNECTING, &us->flags)) {
                US_DEBUGP("Reset interrupted by disconnect\n");
-               goto Done;
+               return -EIO;
        }
 
        US_DEBUGP("Soft reset: clearing bulk-in endpoint halt\n");
@@ -1173,16 +1184,11 @@ static int usb_stor_reset_common(struct us_data *us,
        /* return a result code based on the result of the clear-halts */
        if (result >= 0)
                result = result2;
-       if (result < 0) {
+       if (result < 0)
                US_DEBUGP("Soft reset failed\n");
-               goto Done;
-       }
-       US_DEBUGP("Soft reset done\n");
-       rc = SUCCESS;
-
-  Done:
-       clear_bit(US_FLIDX_RESETTING, &us->flags);
-       return rc;
+       else
+               US_DEBUGP("Soft reset done\n");
+       return result;
 }
 
 /* This issues a CB[I] Reset to the device in question
@@ -1212,3 +1218,32 @@ int usb_stor_Bulk_reset(struct us_data *us)
                                 USB_TYPE_CLASS | USB_RECIP_INTERFACE,
                                 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. */
+int usb_stor_port_reset(struct us_data *us)
+{
+       int result, rc;
+
+       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);
+               } 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);
+               }
+       }
+       return result;
+}