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firewire: ohci: flush AT contexts after bus reset - addendum

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  - on why bus_reset_tasklet flushes AT queues,
  - that commit 76f73ca1b2 can possibly be reverted now.

Signed-off-by: Stefan Richter <stefanr@s5r6.in-berlin.de>
Acked-by: Jarod Wilson <jarod@redhat.com>
This commit is contained in:
Stefan Richter
2011-01-01 15:15:40 +01:00
parent 82b662dc41
commit 78dec56d6a
1 changed files with 7 additions and 0 deletions
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7
drivers/firewire/ohci.c
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@@ -1336,6 +1336,8 @@ static int at_context_queue_packet(struct context *ctx,
* some controllers (like a JMicron JMB381 PCI-e) misbehave and wind * some controllers (like a JMicron JMB381 PCI-e) misbehave and wind
* up stalling out. So we just bail out in software and try again * up stalling out. So we just bail out in software and try again
* later, and everyone is happy. * later, and everyone is happy.
* FIXME: Test of IntEvent.busReset may no longer be necessary since we
* flush AT queues in bus_reset_tasklet.
* FIXME: Document how the locking works. * FIXME: Document how the locking works.
*/ */
if (ohci->generation != packet->generation || if (ohci->generation != packet->generation ||
@@ -1750,6 +1752,11 @@ static void bus_reset_tasklet(unsigned long data)
spin_unlock_irqrestore(&ohci->lock, flags); spin_unlock_irqrestore(&ohci->lock, flags);
/*
* Per OHCI 1.2 draft, clause 7.2.3.3, hardware may leave unsent
* packets in the AT queues and software needs to drain them.
* Some OHCI 1.1 controllers (JMicron) apparently require this too.
*/
at_context_flush(&ohci->at_request_ctx); at_context_flush(&ohci->at_request_ctx);
at_context_flush(&ohci->at_response_ctx); at_context_flush(&ohci->at_response_ctx);