Commit 0e5f231b authored by Alan Stern's avatar Alan Stern Committed by Greg Kroah-Hartman
Browse files

USB: EHCI: defer reclamation of siTDs 



This patch (as1369) fixes a problem in ehci-hcd.  Some controllers
occasionally run into trouble when the driver reclaims siTDs too
quickly.  This can happen while streaming audio; it causes the
controller to crash.

The patch changes siTD reclamation to work the same way as iTD
reclamation: Completed siTDs are stored on a list and not reused until
at least one frame has passed.

Signed-off-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Tested-by: default avatarNate Case <ncase@xes-inc.com>
CC: <stable@kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@suse.de>
parent 5f677f1d

drivers/usb/host/ehci-hcd.c

+1 −0
Original line number Diff line number Diff line
@@ -543,6 +543,7 @@ static int ehci_init(struct usb_hcd *hcd) 
	 */

	ehci->periodic_size = DEFAULT_I_TDPS;

	INIT_LIST_HEAD(&ehci->cached_itd_list);

	INIT_LIST_HEAD(&ehci->cached_sitd_list);

	if ((retval = ehci_mem_init(ehci, GFP_KERNEL)) < 0)

		return retval;

drivers/usb/host/ehci-mem.c

+1 −1
Original line number Diff line number Diff line
@@ -136,7 +136,7 @@ static inline void qh_put (struct ehci_qh *qh) 


static void ehci_mem_cleanup (struct ehci_hcd *ehci)

{

	free_cached_itd_list(ehci);

	free_cached_lists(ehci);

	if (ehci->async)

		qh_put (ehci->async);

	ehci->async = NULL;

drivers/usb/host/ehci-sched.c

+31 −9
Original line number Diff line number Diff line
@@ -510,7 +510,7 @@ static int disable_periodic (struct ehci_hcd *ehci) 
	ehci_writel(ehci, cmd, &ehci->regs->command);

	/* posted write ... */



	free_cached_itd_list(ehci);

	free_cached_lists(ehci);



	ehci->next_uframe = -1;

	return 0;
@@ -2139,13 +2139,27 @@ sitd_complete ( 
			(stream->bEndpointAddress & USB_DIR_IN) ? "in" : "out");

	}

	iso_stream_put (ehci, stream);

	/* OK to recycle this SITD now that its completion callback ran. */



done:

	sitd->urb = NULL;

	if (ehci->clock_frame != sitd->frame) {

		/* OK to recycle this SITD now. */

		sitd->stream = NULL;

		list_move(&sitd->sitd_list, &stream->free_list);

		iso_stream_put(ehci, stream);



	} else {

		/* HW might remember this SITD, so we can't recycle it yet.

		 * Move it to a safe place until a new frame starts.

		 */

		list_move(&sitd->sitd_list, &ehci->cached_sitd_list);

		if (stream->refcount == 2) {

			/* If iso_stream_put() were called here, stream

			 * would be freed.  Instead, just prevent reuse.

			 */

			stream->ep->hcpriv = NULL;

			stream->ep = NULL;

		}

	}

	return retval;

}
@@ -2211,9 +2225,10 @@ done: 


/*-------------------------------------------------------------------------*/



static void free_cached_itd_list(struct ehci_hcd *ehci)

static void free_cached_lists(struct ehci_hcd *ehci)

{

	struct ehci_itd *itd, *n;

	struct ehci_sitd *sitd, *sn;



	list_for_each_entry_safe(itd, n, &ehci->cached_itd_list, itd_list) {

		struct ehci_iso_stream	*stream = itd->stream;
@@ -2221,6 +2236,13 @@ static void free_cached_itd_list(struct ehci_hcd *ehci) 
		list_move(&itd->itd_list, &stream->free_list);

		iso_stream_put(ehci, stream);

	}



	list_for_each_entry_safe(sitd, sn, &ehci->cached_sitd_list, sitd_list) {

		struct ehci_iso_stream	*stream = sitd->stream;

		sitd->stream = NULL;

		list_move(&sitd->sitd_list, &stream->free_list);

		iso_stream_put(ehci, stream);

	}

}



/*-------------------------------------------------------------------------*/
@@ -2247,7 +2269,7 @@ scan_periodic (struct ehci_hcd *ehci) 
		clock_frame = -1;

	}

	if (ehci->clock_frame != clock_frame) {

		free_cached_itd_list(ehci);

		free_cached_lists(ehci);

		ehci->clock_frame = clock_frame;

	}

	clock %= mod;
@@ -2414,7 +2436,7 @@ restart: 
			clock = now;

			clock_frame = clock >> 3;

			if (ehci->clock_frame != clock_frame) {

				free_cached_itd_list(ehci);

				free_cached_lists(ehci);

				ehci->clock_frame = clock_frame;

			}

		} else {

drivers/usb/host/ehci.h

+3 −2
Original line number Diff line number Diff line
@@ -87,8 +87,9 @@ struct ehci_hcd { /* one per controller */ 
	int			next_uframe;	/* scan periodic, start here */

	unsigned		periodic_sched;	/* periodic activity count */



	/* list of itds completed while clock_frame was still active */

	/* list of itds & sitds completed while clock_frame was still active */

	struct list_head	cached_itd_list;

	struct list_head	cached_sitd_list;

	unsigned		clock_frame;



	/* per root hub port */
@@ -195,7 +196,7 @@ timer_action_done (struct ehci_hcd *ehci, enum ehci_timer_action action) 
	clear_bit (action, &ehci->actions);

}



static void free_cached_itd_list(struct ehci_hcd *ehci);

static void free_cached_lists(struct ehci_hcd *ehci);



/*-------------------------------------------------------------------------*/

CRA Git | Maintained and supported by SUSTech CRA and CCSE