aboutsummaryrefslogtreecommitdiff
path: root/drivers/usb/host/ehci-sched.c
diff options
context:
space:
mode:
authorAlan Stern <stern@rowland.harvard.edu>2012-07-11 11:22:39 -0400
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-07-16 16:54:26 -0700
commit8c5bf7be56f1a8aecc1f802f132d53f556a9bc45 (patch)
treed3b22a284f3f81b804bf9898928f866cfb8a45cd /drivers/usb/host/ehci-sched.c
parent55934eb3b9fa52eb53b9d7342267fc73c38206aa (diff)
downloadlinux-stericsson-8c5bf7be56f1a8aecc1f802f132d53f556a9bc45.tar.gz
USB: EHCI: don't refcount iso_stream structures
This patch (as1580) makes ehci_iso_stream structures behave more like QHs, in that they will remain allocated until their isochronous endpoint is disabled. This will come in useful in the future, when periodic bandwidth gets allocated as an altsetting is installed rather than on-the-fly. For now, the change to the ehci_iso_stream lifetimes means that each structure is always deallocated at exactly one spot in ehci_endpoint_disable() and never used again. As a result, it is no longer necessary to use reference counting on these things, and the patch removes it. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/usb/host/ehci-sched.c')
-rw-r--r--drivers/usb/host/ehci-sched.c53
1 files changed, 6 insertions, 47 deletions
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c
index 1e4f13c11b6a..11b2f21d7ac1 100644
--- a/drivers/usb/host/ehci-sched.c
+++ b/drivers/usb/host/ehci-sched.c
@@ -934,7 +934,6 @@ iso_stream_alloc (gfp_t mem_flags)
INIT_LIST_HEAD(&stream->td_list);
INIT_LIST_HEAD(&stream->free_list);
stream->next_uframe = -1;
- stream->refcount = 1;
}
return stream;
}
@@ -1034,32 +1033,6 @@ iso_stream_init (
stream->maxp = maxp;
}
-static void
-iso_stream_put(struct ehci_hcd *ehci, struct ehci_iso_stream *stream)
-{
- stream->refcount--;
-
- /* free whenever just a dev->ep reference remains.
- * not like a QH -- no persistent state (toggle, halt)
- */
- if (stream->refcount == 1) {
- // BUG_ON (!list_empty(&stream->td_list));
-
- if (stream->ep)
- stream->ep->hcpriv = NULL;
-
- kfree(stream);
- }
-}
-
-static inline struct ehci_iso_stream *
-iso_stream_get (struct ehci_iso_stream *stream)
-{
- if (likely (stream != NULL))
- stream->refcount++;
- return stream;
-}
-
static struct ehci_iso_stream *
iso_stream_find (struct ehci_hcd *ehci, struct urb *urb)
{
@@ -1080,7 +1053,6 @@ iso_stream_find (struct ehci_hcd *ehci, struct urb *urb)
if (unlikely (stream == NULL)) {
stream = iso_stream_alloc(GFP_ATOMIC);
if (likely (stream != NULL)) {
- /* dev->ep owns the initial refcount */
ep->hcpriv = stream;
stream->ep = ep;
iso_stream_init(ehci, stream, urb->dev, urb->pipe,
@@ -1095,9 +1067,6 @@ iso_stream_find (struct ehci_hcd *ehci, struct urb *urb)
stream = NULL;
}
- /* caller guarantees an eventual matching iso_stream_put */
- stream = iso_stream_get (stream);
-
spin_unlock_irqrestore (&ehci->lock, flags);
return stream;
}
@@ -1611,7 +1580,7 @@ static void itd_link_urb(
itd = list_entry (iso_sched->td_list.next,
struct ehci_itd, itd_list);
list_move_tail (&itd->itd_list, &stream->td_list);
- itd->stream = iso_stream_get (stream);
+ itd->stream = stream;
itd->urb = urb;
itd_init (ehci, stream, itd);
}
@@ -1735,7 +1704,6 @@ itd_complete (
dev->devpath, stream->bEndpointAddress & 0x0f,
(stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out");
}
- iso_stream_put (ehci, stream);
done:
itd->urb = NULL;
@@ -1750,7 +1718,6 @@ done:
start_free_itds(ehci);
}
- iso_stream_put(ehci, stream);
return retval;
}
@@ -1807,12 +1774,9 @@ static int itd_submit (struct ehci_hcd *ehci, struct urb *urb,
itd_link_urb (ehci, urb, ehci->periodic_size << 3, stream);
else
usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci), urb);
-done_not_linked:
+ done_not_linked:
spin_unlock_irqrestore (&ehci->lock, flags);
-
-done:
- if (unlikely (status < 0))
- iso_stream_put (ehci, stream);
+ done:
return status;
}
@@ -2028,7 +1992,7 @@ static void sitd_link_urb(
sitd = list_entry (sched->td_list.next,
struct ehci_sitd, sitd_list);
list_move_tail (&sitd->sitd_list, &stream->td_list);
- sitd->stream = iso_stream_get (stream);
+ sitd->stream = stream;
sitd->urb = urb;
sitd_patch(ehci, stream, sitd, sched, packet);
@@ -2126,7 +2090,6 @@ sitd_complete (
dev->devpath, stream->bEndpointAddress & 0x0f,
(stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out");
}
- iso_stream_put (ehci, stream);
done:
sitd->urb = NULL;
@@ -2141,7 +2104,6 @@ done:
start_free_itds(ehci);
}
- iso_stream_put(ehci, stream);
return retval;
}
@@ -2195,12 +2157,9 @@ static int sitd_submit (struct ehci_hcd *ehci, struct urb *urb,
sitd_link_urb (ehci, urb, ehci->periodic_size << 3, stream);
else
usb_hcd_unlink_urb_from_ep(ehci_to_hcd(ehci), urb);
-done_not_linked:
+ done_not_linked:
spin_unlock_irqrestore (&ehci->lock, flags);
-
-done:
- if (status < 0)
- iso_stream_put (ehci, stream);
+ done:
return status;
}