diff options
Diffstat (limited to 'drivers/usb/host/ehci-q.c')
| -rw-r--r-- | drivers/usb/host/ehci-q.c | 104 |
1 files changed, 80 insertions, 24 deletions
diff --git a/drivers/usb/host/ehci-q.c b/drivers/usb/host/ehci-q.c index aad0777240d3..eca3710d8fc4 100644 --- a/drivers/usb/host/ehci-q.c +++ b/drivers/usb/host/ehci-q.c @@ -394,6 +394,7 @@ qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh) goto retry_xacterr; } stopped = 1; + qh->unlink_reason |= QH_UNLINK_HALTED; /* magic dummy for some short reads; qh won't advance. * that silicon quirk can kick in with this dummy too. @@ -408,6 +409,7 @@ qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh) && !(qtd->hw_alt_next & EHCI_LIST_END(ehci))) { stopped = 1; + qh->unlink_reason |= QH_UNLINK_SHORT_READ; } /* stop scanning when we reach qtds the hc is using */ @@ -420,8 +422,10 @@ qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh) stopped = 1; /* cancel everything if we halt, suspend, etc */ - if (ehci->rh_state < EHCI_RH_RUNNING) + if (ehci->rh_state < EHCI_RH_RUNNING) { last_status = -ESHUTDOWN; + qh->unlink_reason |= QH_UNLINK_SHUTDOWN; + } /* this qtd is active; skip it unless a previous qtd * for its urb faulted, or its urb was canceled. @@ -538,10 +542,10 @@ qh_completions (struct ehci_hcd *ehci, struct ehci_qh *qh) * except maybe high bandwidth ... */ if (stopped != 0 || hw->hw_qtd_next == EHCI_LIST_END(ehci)) - qh->exception = 1; + qh->unlink_reason |= QH_UNLINK_DUMMY_OVERLAY; /* Let the caller know if the QH needs to be unlinked. */ - return qh->exception; + return qh->unlink_reason; } /*-------------------------------------------------------------------------*/ @@ -1003,7 +1007,7 @@ static void qh_link_async (struct ehci_hcd *ehci, struct ehci_qh *qh) qh->qh_state = QH_STATE_LINKED; qh->xacterrs = 0; - qh->exception = 0; + qh->unlink_reason = 0; /* qtd completions reported later by interrupt */ enable_async(ehci); @@ -1279,17 +1283,13 @@ static void single_unlink_async(struct ehci_hcd *ehci, struct ehci_qh *qh) static void start_iaa_cycle(struct ehci_hcd *ehci) { - /* Do nothing if an IAA cycle is already running */ - if (ehci->iaa_in_progress) - return; - ehci->iaa_in_progress = true; - /* If the controller isn't running, we don't have to wait for it */ if (unlikely(ehci->rh_state < EHCI_RH_RUNNING)) { end_unlink_async(ehci); - /* Otherwise start a new IAA cycle */ - } else if (likely(ehci->rh_state == EHCI_RH_RUNNING)) { + /* Otherwise start a new IAA cycle if one isn't already running */ + } else if (ehci->rh_state == EHCI_RH_RUNNING && + !ehci->iaa_in_progress) { /* Make sure the unlinks are all visible to the hardware */ wmb(); @@ -1297,17 +1297,13 @@ static void start_iaa_cycle(struct ehci_hcd *ehci) ehci_writel(ehci, ehci->command | CMD_IAAD, &ehci->regs->command); ehci_readl(ehci, &ehci->regs->command); + ehci->iaa_in_progress = true; ehci_enable_event(ehci, EHCI_HRTIMER_IAA_WATCHDOG, true); } } -/* the async qh for the qtds being unlinked are now gone from the HC */ - -static void end_unlink_async(struct ehci_hcd *ehci) +static void end_iaa_cycle(struct ehci_hcd *ehci) { - struct ehci_qh *qh; - bool early_exit; - if (ehci->has_synopsys_hc_bug) ehci_writel(ehci, (u32) ehci->async->qh_dma, &ehci->regs->async_next); @@ -1315,6 +1311,16 @@ static void end_unlink_async(struct ehci_hcd *ehci) /* The current IAA cycle has ended */ ehci->iaa_in_progress = false; + end_unlink_async(ehci); +} + +/* See if the async qh for the qtds being unlinked are now gone from the HC */ + +static void end_unlink_async(struct ehci_hcd *ehci) +{ + struct ehci_qh *qh; + bool early_exit; + if (list_empty(&ehci->async_unlink)) return; qh = list_first_entry(&ehci->async_unlink, struct ehci_qh, @@ -1335,14 +1341,60 @@ static void end_unlink_async(struct ehci_hcd *ehci) * after the IAA interrupt occurs. In self-defense, always go * through two IAA cycles for each QH. */ - else if (qh->qh_state == QH_STATE_UNLINK_WAIT) { + else if (qh->qh_state == QH_STATE_UNLINK) { + /* + * Second IAA cycle has finished. Process only the first + * waiting QH (NVIDIA (?) bug). + */ + list_move_tail(&qh->unlink_node, &ehci->async_idle); + } + + /* + * AMD/ATI (?) bug: The HC can continue to use an active QH long + * after the IAA interrupt occurs. To prevent problems, QHs that + * may still be active will wait until 2 ms have passed with no + * change to the hw_current and hw_token fields (this delay occurs + * between the two IAA cycles). + * + * The EHCI spec (4.8.2) says that active QHs must not be removed + * from the async schedule and recommends waiting until the QH + * goes inactive. This is ridiculous because the QH will _never_ + * become inactive if the endpoint NAKs indefinitely. + */ + + /* Some reasons for unlinking guarantee the QH can't be active */ + else if (qh->unlink_reason & (QH_UNLINK_HALTED | + QH_UNLINK_SHORT_READ | QH_UNLINK_DUMMY_OVERLAY)) + goto DelayDone; + + /* The QH can't be active if the queue was and still is empty... */ + else if ((qh->unlink_reason & QH_UNLINK_QUEUE_EMPTY) && + list_empty(&qh->qtd_list)) + goto DelayDone; + + /* ... or if the QH has halted */ + else if (qh->hw->hw_token & cpu_to_hc32(ehci, QTD_STS_HALT)) + goto DelayDone; + + /* Otherwise we have to wait until the QH stops changing */ + else { + __hc32 qh_current, qh_token; + + qh_current = qh->hw->hw_current; + qh_token = qh->hw->hw_token; + if (qh_current != ehci->old_current || + qh_token != ehci->old_token) { + ehci->old_current = qh_current; + ehci->old_token = qh_token; + ehci_enable_event(ehci, + EHCI_HRTIMER_ACTIVE_UNLINK, true); + return; + } + DelayDone: qh->qh_state = QH_STATE_UNLINK; early_exit = true; } - - /* Otherwise process only the first waiting QH (NVIDIA bug?) */ - else - list_move_tail(&qh->unlink_node, &ehci->async_idle); + ehci->old_current = ~0; /* Prepare for next QH */ /* Start a new IAA cycle if any QHs are waiting for it */ if (!list_empty(&ehci->async_unlink)) @@ -1395,6 +1447,7 @@ static void unlink_empty_async(struct ehci_hcd *ehci) /* If nothing else is being unlinked, unlink the last empty QH */ if (list_empty(&ehci->async_unlink) && qh_to_unlink) { + qh_to_unlink->unlink_reason |= QH_UNLINK_QUEUE_EMPTY; start_unlink_async(ehci, qh_to_unlink); --count; } @@ -1406,8 +1459,10 @@ static void unlink_empty_async(struct ehci_hcd *ehci) } } +#ifdef CONFIG_PM + /* The root hub is suspended; unlink all the async QHs */ -static void __maybe_unused unlink_empty_async_suspended(struct ehci_hcd *ehci) +static void unlink_empty_async_suspended(struct ehci_hcd *ehci) { struct ehci_qh *qh; @@ -1416,9 +1471,10 @@ static void __maybe_unused unlink_empty_async_suspended(struct ehci_hcd *ehci) WARN_ON(!list_empty(&qh->qtd_list)); single_unlink_async(ehci, qh); } - start_iaa_cycle(ehci); } +#endif + /* makes sure the async qh will become idle */ /* caller must own ehci->lock */ |