USB: cleanup for previous patches

This patch (as951) cleans up a few loose ends from earlier patches.
Redundant checks for non-NULL urb->dev are removed, as are checks of
urb->dev->bus (which can never be NULL).  Conversely, a check for
non-NULL urb->ep is added to the unlink paths.

A homegrown round-down-to-power-of-2 loop is simplified by using the
ilog2 routine.  The comparison in usb_urb_dir_in() is made more
transparent.

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

1 files changed, 7 insertions, 6 deletions

diff --git a/drivers/usb/core/urb.c b/drivers/usb/core/urb.c
index 1acca8696bcd..19f5f66c2733 100644
--- a/drivers/usb/core/urb.c
+++ b/drivers/usb/core/urb.c
@@ -3,6 +3,7 @@
 #include <linux/bitops.h>
 #include <linux/slab.h>
 #include <linux/init.h>
+#include <linux/log2.h>
 #include <linux/usb.h>
 #include <linux/wait.h>
 #include "hcd.h"
@@ -441,10 +442,8 @@ int usb_submit_urb(struct urb *urb, gfp_t mem_flags)
                 default:
                         return -EINVAL;
                 }
-                /* power of two? */
-                while (max > urb->interval)
-                        max >>= 1;
-                urb->interval = max;
+                /* Round down to a power of 2, no more than max */
+                urb->interval = min(max, 1 << ilog2(urb->interval));
         }
 
         return usb_hcd_submit_urb(urb, mem_flags);
@@ -513,8 +512,10 @@ int usb_unlink_urb(struct urb *urb)
 {
         if (!urb)
                 return -EINVAL;
-        if (!(urb->dev && urb->dev->bus))
+        if (!urb->dev)
                 return -ENODEV;
+        if (!urb->ep)
+                return -EIDRM;
         return usb_hcd_unlink_urb(urb, -ECONNRESET);
 }
 
@@ -541,7 +542,7 @@ int usb_unlink_urb(struct urb *urb)
 void usb_kill_urb(struct urb *urb)
 {
         might_sleep();
-        if (!(urb && urb->dev && urb->dev->bus))
+        if (!(urb && urb->dev && urb->ep))
                 return;
         spin_lock_irq(&urb->lock);
         ++urb->reject;