diff options
| author | Alan Stern <stern@rowland.harvard.edu> | 2014-12-04 18:21:56 +0300 |
|---|---|---|
| committer | Luis Henriques <luis.henriques@canonical.com> | 2015-01-22 19:33:19 +0300 |
| commit | cbf7cdd62e2bfcab4d82bf50080a7cee45f4530b (patch) | |
| tree | d35056a8c0882856db2b5bf07612b23e5511fee9 | |
| parent | 4ecfd6af48e0d211a14ef4d5773f8ba83346b631 (diff) | |
| download | linux-cbf7cdd62e2bfcab4d82bf50080a7cee45f4530b.tar.xz | |
USB: EHCI: fix initialization bug in iso_stream_schedule()
commit 6d89252a998a695ecb0348fc2d717dc33d90cae9 upstream.
Commit c3ee9b76aa93 (EHCI: improved logic for isochronous scheduling)
introduced the idea of using ehci->last_iso_frame as the origin (or
base) for the circular calculations involved in modifying the
isochronous schedule. However, the new code it added used
ehci->last_iso_frame before the value was properly initialized. This
patch rectifies the mistake by moving the initialization lines earlier
in iso_stream_schedule().
This fixes Bugzilla #72891.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Fixes: c3ee9b76aa93
Reported-by: Joe Bryant <tenminjoe@yahoo.com>
Tested-by: Joe Bryant <tenminjoe@yahoo.com>
Tested-by: Martin Long <martin@longhome.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
| -rw-r--r-- | drivers/usb/host/ehci-sched.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c index e113fd73aeae..c399606f154e 100644 --- a/drivers/usb/host/ehci-sched.c +++ b/drivers/usb/host/ehci-sched.c @@ -1581,6 +1581,10 @@ iso_stream_schedule ( else next = (now + 2 + 7) & ~0x07; /* full frame cache */ + /* If needed, initialize last_iso_frame so that this URB will be seen */ + if (ehci->isoc_count == 0) + ehci->last_iso_frame = now >> 3; + /* * Use ehci->last_iso_frame as the base. There can't be any * TDs scheduled for earlier than that. @@ -1671,10 +1675,6 @@ iso_stream_schedule ( urb->start_frame = start & (mod - 1); if (!stream->highspeed) urb->start_frame >>= 3; - - /* Make sure scan_isoc() sees these */ - if (ehci->isoc_count == 0) - ehci->last_iso_frame = now >> 3; return status; fail: |