From david-b@pacbell.net Fri Jan 20 17:25:17 2006 From: David Brownell To: Greg KH Subject: USB: EHCI unlink tweaks Date: Fri, 20 Jan 2006 14:35:55 -0800 Message-Id: <200601201435.56129.david-b@pacbell.net> This patch modifies the behavior of the EHCI driver in an unlink path that seems to be causing various issues on some systems. Those problems have included issues with disconnection, driver unbinding, and similar cases where urb unlinking would just not work right. This patch should help avoid those problems by not turning off the async (control/bulk) schedule until it's not expecting an "async advance" IRQ, which comes from the processing passing the schedule head. Whether the driver attempts to do such things is dependent on system timings, so many folk would never have seen these problems. Signed-off-by: David Brownell Signed-off-by: Greg Kroah-Hartman --- drivers/usb/host/ehci-q.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) --- gregkh-2.6.orig/drivers/usb/host/ehci-q.c +++ gregkh-2.6/drivers/usb/host/ehci-q.c @@ -1022,12 +1022,14 @@ static void start_unlink_async (struct e /* stop async schedule right now? */ if (unlikely (qh == ehci->async)) { /* can't get here without STS_ASS set */ - if (ehci_to_hcd(ehci)->state != HC_STATE_HALT) { + if (ehci_to_hcd(ehci)->state != HC_STATE_HALT + && !ehci->reclaim) { + /* ... and CMD_IAAD clear */ writel (cmd & ~CMD_ASE, &ehci->regs->command); wmb (); // handshake later, if we need to + timer_action_done (ehci, TIMER_ASYNC_OFF); } - timer_action_done (ehci, TIMER_ASYNC_OFF); return; }