diff options
| author | Clemens Ladisch <clemens@ladisch.de> | 2010-03-01 11:12:50 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-03-19 17:24:05 +0300 |
| commit | 92bc3648e6027384479852b770a542722fadee7c (patch) | |
| tree | 9803348ef9fd9186ad375abf89a4e7862e9badc4 /drivers/usb/host/ehci-sched.c | |
| parent | bf162019b7f5bda9eb3241ae22de831df2126132 (diff) | |
| download | linux-92bc3648e6027384479852b770a542722fadee7c.tar.xz | |
USB: EHCI: fix ITD list order
When isochronous URBs are shorter than one frame and when more than one
ITD in a frame has been completed before the interrupt can be handled,
scan_periodic() completes the URBs in the order in which they are found
in the descriptor list. Therefore, the descriptor list must contain the
ITDs in the correct order, i.e., a new ITD must be linked in after any
previous ITDs of the same endpoint.
This should fix garbled capture data in the USB audio drivers.
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Reported-by: Colin Fletcher <colin.m.fletcher@googlemail.com>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/usb/host/ehci-sched.c')
| -rw-r--r-- | drivers/usb/host/ehci-sched.c | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/drivers/usb/host/ehci-sched.c b/drivers/usb/host/ehci-sched.c index 39340ae00ac4..cd1e8bf5327e 100644 --- a/drivers/usb/host/ehci-sched.c +++ b/drivers/usb/host/ehci-sched.c @@ -1565,13 +1565,27 @@ itd_patch( static inline void itd_link (struct ehci_hcd *ehci, unsigned frame, struct ehci_itd *itd) { - /* always prepend ITD/SITD ... only QH tree is order-sensitive */ - itd->itd_next = ehci->pshadow [frame]; - itd->hw_next = ehci->periodic [frame]; - ehci->pshadow [frame].itd = itd; + union ehci_shadow *prev = &ehci->pshadow[frame]; + __hc32 *hw_p = &ehci->periodic[frame]; + union ehci_shadow here = *prev; + __hc32 type = 0; + + /* skip any iso nodes which might belong to previous microframes */ + while (here.ptr) { + type = Q_NEXT_TYPE(ehci, *hw_p); + if (type == cpu_to_hc32(ehci, Q_TYPE_QH)) + break; + prev = periodic_next_shadow(ehci, prev, type); + hw_p = shadow_next_periodic(ehci, &here, type); + here = *prev; + } + + itd->itd_next = here; + itd->hw_next = *hw_p; + prev->itd = itd; itd->frame = frame; wmb (); - ehci->periodic[frame] = cpu_to_hc32(ehci, itd->itd_dma | Q_TYPE_ITD); + *hw_p = cpu_to_hc32(ehci, itd->itd_dma | Q_TYPE_ITD); } /* fit urb's itds into the selected schedule slot; activate as needed */ |