USB: EHCI: convert singly-linked lists to list_heads

This patch (as1664) converts ehci-hcd's async_unlink, async_iaa, and
intr_unlink from singly-linked lists to standard doubly-linked
list_heads.  Originally it didn't seem necessary to use list_heads,
because items are always added to and removed from these lists in FIFO
order.  But now with more list processing going on, it's easier to use
the standard routines than continue with a roll-your-own approach.

I don't know if the code ends up being notably shorter, but the
patterns will be more familiar to any kernel hacker.

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

1 files changed, 4 insertions, 6 deletions

diff --git a/drivers/usb/host/ehci.h b/drivers/usb/host/ehci.h
index 6815209511aa..13f67041502e 100644
--- a/drivers/usb/host/ehci.h
+++ b/drivers/usb/host/ehci.h
@@ -128,9 +128,8 @@ struct ehci_hcd {			/* one per controller */
         /* async schedule support */
         struct ehci_qh          *async;
         struct ehci_qh          *dummy;         /* For AMD quirk use */
-        struct ehci_qh          *async_unlink;
-        struct ehci_qh          *async_unlink_last;
-        struct ehci_qh          *async_iaa;
+        struct list_head        async_unlink;
+        struct list_head        async_iaa;
         unsigned                async_unlink_cycle;
         unsigned                async_count;    /* async activity count */
 
@@ -143,8 +142,7 @@ struct ehci_hcd {			/* one per controller */
         unsigned                i_thresh;       /* uframes HC might cache */
 
         union ehci_shadow       *pshadow;       /* mirror hw periodic table */
-        struct ehci_qh          *intr_unlink;
-        struct ehci_qh          *intr_unlink_last;
+        struct list_head        intr_unlink;
         unsigned                intr_unlink_cycle;
         unsigned                now_frame;      /* frame from HC hardware */
         unsigned                last_iso_frame; /* last frame scanned for iso */
@@ -380,7 +378,7 @@ struct ehci_qh {
         struct list_head        qtd_list;       /* sw qtd list */
         struct list_head        intr_node;      /* list of intr QHs */
         struct ehci_qtd         *dummy;
-        struct ehci_qh          *unlink_next;   /* next on unlink list */
+        struct list_head        unlink_node;
 
         unsigned                unlink_cycle;