diff options
Diffstat (limited to 'drivers/usb/host/uhci-q.c')
| -rw-r--r-- | drivers/usb/host/uhci-q.c | 1765 |
1 files changed, 1765 insertions, 0 deletions
diff --git a/drivers/usb/host/uhci-q.c b/drivers/usb/host/uhci-q.c new file mode 100644 index 0000000..5631d89 --- /dev/null +++ b/drivers/usb/host/uhci-q.c @@ -0,0 +1,1765 @@ +/* + * Universal Host Controller Interface driver for USB. + * + * Maintainer: Alan Stern <stern@rowland.harvard.edu> + * + * (C) Copyright 1999 Linus Torvalds + * (C) Copyright 1999-2002 Johannes Erdfelt, johannes@erdfelt.com + * (C) Copyright 1999 Randy Dunlap + * (C) Copyright 1999 Georg Acher, acher@in.tum.de + * (C) Copyright 1999 Deti Fliegl, deti@fliegl.de + * (C) Copyright 1999 Thomas Sailer, sailer@ife.ee.ethz.ch + * (C) Copyright 1999 Roman Weissgaerber, weissg@vienna.at + * (C) Copyright 2000 Yggdrasil Computing, Inc. (port of new PCI interface + * support from usb-ohci.c by Adam Richter, adam@yggdrasil.com). + * (C) Copyright 1999 Gregory P. Smith (from usb-ohci.c) + * (C) Copyright 2004-2007 Alan Stern, stern@rowland.harvard.edu + */ + + +/* + * Technically, updating td->status here is a race, but it's not really a + * problem. The worst that can happen is that we set the IOC bit again + * generating a spurious interrupt. We could fix this by creating another + * QH and leaving the IOC bit always set, but then we would have to play + * games with the FSBR code to make sure we get the correct order in all + * the cases. I don't think it's worth the effort + */ +static void uhci_set_next_interrupt(struct uhci_hcd *uhci) +{ + if (uhci->is_stopped) + mod_timer(&uhci_to_hcd(uhci)->rh_timer, jiffies); + uhci->term_td->status |= cpu_to_le32(TD_CTRL_IOC); +} + +static inline void uhci_clear_next_interrupt(struct uhci_hcd *uhci) +{ + uhci->term_td->status &= ~cpu_to_le32(TD_CTRL_IOC); +} + + +/* + * Full-Speed Bandwidth Reclamation (FSBR). + * We turn on FSBR whenever a queue that wants it is advancing, + * and leave it on for a short time thereafter. + */ +static void uhci_fsbr_on(struct uhci_hcd *uhci) +{ + struct uhci_qh *lqh; + + /* The terminating skeleton QH always points back to the first + * FSBR QH. Make the last async QH point to the terminating + * skeleton QH. */ + uhci->fsbr_is_on = 1; + lqh = list_entry(uhci->skel_async_qh->node.prev, + struct uhci_qh, node); + lqh->link = LINK_TO_QH(uhci->skel_term_qh); +} + +static void uhci_fsbr_off(struct uhci_hcd *uhci) +{ + struct uhci_qh *lqh; + + /* Remove the link from the last async QH to the terminating + * skeleton QH. */ + uhci->fsbr_is_on = 0; + lqh = list_entry(uhci->skel_async_qh->node.prev, + struct uhci_qh, node); + lqh->link = UHCI_PTR_TERM; +} + +static void uhci_add_fsbr(struct uhci_hcd *uhci, struct urb *urb) +{ + struct urb_priv *urbp = urb->hcpriv; + + if (!(urb->transfer_flags & URB_NO_FSBR)) + urbp->fsbr = 1; +} + +static void uhci_urbp_wants_fsbr(struct uhci_hcd *uhci, struct urb_priv *urbp) +{ + if (urbp->fsbr) { + uhci->fsbr_is_wanted = 1; + if (!uhci->fsbr_is_on) + uhci_fsbr_on(uhci); + else if (uhci->fsbr_expiring) { + uhci->fsbr_expiring = 0; + del_timer(&uhci->fsbr_timer); + } + } +} + +static void uhci_fsbr_timeout(unsigned long _uhci) +{ + struct uhci_hcd *uhci = (struct uhci_hcd *) _uhci; + unsigned long flags; + + spin_lock_irqsave(&uhci->lock, flags); + if (uhci->fsbr_expiring) { + uhci->fsbr_expiring = 0; + uhci_fsbr_off(uhci); + } + spin_unlock_irqrestore(&uhci->lock, flags); +} + + +static struct uhci_td *uhci_alloc_td(struct uhci_hcd *uhci) +{ + dma_addr_t dma_handle; + struct uhci_td *td; + + td = dma_pool_alloc(uhci->td_pool, GFP_ATOMIC, &dma_handle); + if (!td) + return NULL; + + td->dma_handle = dma_handle; + td->frame = -1; + + INIT_LIST_HEAD(&td->list); + INIT_LIST_HEAD(&td->fl_list); + + return td; +} + +static void uhci_free_td(struct uhci_hcd *uhci, struct uhci_td *td) +{ + if (!list_empty(&td->list)) + dev_WARN(uhci_dev(uhci), "td %p still in list!\n", td); + if (!list_empty(&td->fl_list)) + dev_WARN(uhci_dev(uhci), "td %p still in fl_list!\n", td); + + dma_pool_free(uhci->td_pool, td, td->dma_handle); +} + +static inline void uhci_fill_td(struct uhci_td *td, u32 status, + u32 token, u32 buffer) +{ + td->status = cpu_to_le32(status); + td->token = cpu_to_le32(token); + td->buffer = cpu_to_le32(buffer); +} + +static void uhci_add_td_to_urbp(struct uhci_td *td, struct urb_priv *urbp) +{ + list_add_tail(&td->list, &urbp->td_list); +} + +static void uhci_remove_td_from_urbp(struct uhci_td *td) +{ + list_del_init(&td->list); +} + +/* + * We insert Isochronous URBs directly into the frame list at the beginning + */ +static inline void uhci_insert_td_in_frame_list(struct uhci_hcd *uhci, + struct uhci_td *td, unsigned framenum) +{ + framenum &= (UHCI_NUMFRAMES - 1); + + td->frame = framenum; + + /* Is there a TD already mapped there? */ + if (uhci->frame_cpu[framenum]) { + struct uhci_td *ftd, *ltd; + + ftd = uhci->frame_cpu[framenum]; + ltd = list_entry(ftd->fl_list.prev, struct uhci_td, fl_list); + + list_add_tail(&td->fl_list, &ftd->fl_list); + + td->link = ltd->link; + wmb(); + ltd->link = LINK_TO_TD(td); + } else { + td->link = uhci->frame[framenum]; + wmb(); + uhci->frame[framenum] = LINK_TO_TD(td); + uhci->frame_cpu[framenum] = td; + } +} + +static inline void uhci_remove_td_from_frame_list(struct uhci_hcd *uhci, + struct uhci_td *td) +{ + /* If it's not inserted, don't remove it */ + if (td->frame == -1) { + WARN_ON(!list_empty(&td->fl_list)); + return; + } + + if (uhci->frame_cpu[td->frame] == td) { + if (list_empty(&td->fl_list)) { + uhci->frame[td->frame] = td->link; + uhci->frame_cpu[td->frame] = NULL; + } else { + struct uhci_td *ntd; + + ntd = list_entry(td->fl_list.next, struct uhci_td, fl_list); + uhci->frame[td->frame] = LINK_TO_TD(ntd); + uhci->frame_cpu[td->frame] = ntd; + } + } else { + struct uhci_td *ptd; + + ptd = list_entry(td->fl_list.prev, struct uhci_td, fl_list); + ptd->link = td->link; + } + + list_del_init(&td->fl_list); + td->frame = -1; +} + +static inline void uhci_remove_tds_from_frame(struct uhci_hcd *uhci, + unsigned int framenum) +{ + struct uhci_td *ftd, *ltd; + + framenum &= (UHCI_NUMFRAMES - 1); + + ftd = uhci->frame_cpu[framenum]; + if (ftd) { + ltd = list_entry(ftd->fl_list.prev, struct uhci_td, fl_list); + uhci->frame[framenum] = ltd->link; + uhci->frame_cpu[framenum] = NULL; + + while (!list_empty(&ftd->fl_list)) + list_del_init(ftd->fl_list.prev); + } +} + +/* + * Remove all the TDs for an Isochronous URB from the frame list + */ +static void uhci_unlink_isochronous_tds(struct uhci_hcd *uhci, struct urb *urb) +{ + struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv; + struct uhci_td *td; + + list_for_each_entry(td, &urbp->td_list, list) + uhci_remove_td_from_frame_list(uhci, td); +} + +static struct uhci_qh *uhci_alloc_qh(struct uhci_hcd *uhci, + struct usb_device *udev, struct usb_host_endpoint *hep) +{ + dma_addr_t dma_handle; + struct uhci_qh *qh; + + qh = dma_pool_alloc(uhci->qh_pool, GFP_ATOMIC, &dma_handle); + if (!qh) + return NULL; + + memset(qh, 0, sizeof(*qh)); + qh->dma_handle = dma_handle; + + qh->element = UHCI_PTR_TERM; + qh->link = UHCI_PTR_TERM; + + INIT_LIST_HEAD(&qh->queue); + INIT_LIST_HEAD(&qh->node); + + if (udev) { /* Normal QH */ + qh->type = hep->desc.bmAttributes & USB_ENDPOINT_XFERTYPE_MASK; + if (qh->type != USB_ENDPOINT_XFER_ISOC) { + qh->dummy_td = uhci_alloc_td(uhci); + if (!qh->dummy_td) { + dma_pool_free(uhci->qh_pool, qh, dma_handle); + return NULL; + } + } + qh->state = QH_STATE_IDLE; + qh->hep = hep; + qh->udev = udev; + hep->hcpriv = qh; + + if (qh->type == USB_ENDPOINT_XFER_INT || + qh->type == USB_ENDPOINT_XFER_ISOC) + qh->load = usb_calc_bus_time(udev->speed, + usb_endpoint_dir_in(&hep->desc), + qh->type == USB_ENDPOINT_XFER_ISOC, + le16_to_cpu(hep->desc.wMaxPacketSize)) + / 1000 + 1; + + } else { /* Skeleton QH */ + qh->state = QH_STATE_ACTIVE; + qh->type = -1; + } + return qh; +} + +static void uhci_free_qh(struct uhci_hcd *uhci, struct uhci_qh *qh) +{ + WARN_ON(qh->state != QH_STATE_IDLE && qh->udev); + if (!list_empty(&qh->queue)) + dev_WARN(uhci_dev(uhci), "qh %p list not empty!\n", qh); + + list_del(&qh->node); + if (qh->udev) { + qh->hep->hcpriv = NULL; + if (qh->dummy_td) + uhci_free_td(uhci, qh->dummy_td); + } + dma_pool_free(uhci->qh_pool, qh, qh->dma_handle); +} + +/* + * When a queue is stopped and a dequeued URB is given back, adjust + * the previous TD link (if the URB isn't first on the queue) or + * save its toggle value (if it is first and is currently executing). + * + * Returns 0 if the URB should not yet be given back, 1 otherwise. + */ +static int uhci_cleanup_queue(struct uhci_hcd *uhci, struct uhci_qh *qh, + struct urb *urb) +{ + struct urb_priv *urbp = urb->hcpriv; + struct uhci_td *td; + int ret = 1; + + /* Isochronous pipes don't use toggles and their TD link pointers + * get adjusted during uhci_urb_dequeue(). But since their queues + * cannot truly be stopped, we have to watch out for dequeues + * occurring after the nominal unlink frame. */ + if (qh->type == USB_ENDPOINT_XFER_ISOC) { + ret = (uhci->frame_number + uhci->is_stopped != + qh->unlink_frame); + goto done; + } + + /* If the URB isn't first on its queue, adjust the link pointer + * of the last TD in the previous URB. The toggle doesn't need + * to be saved since this URB can't be executing yet. */ + if (qh->queue.next != &urbp->node) { + struct urb_priv *purbp; + struct uhci_td *ptd; + + purbp = list_entry(urbp->node.prev, struct urb_priv, node); + WARN_ON(list_empty(&purbp->td_list)); + ptd = list_entry(purbp->td_list.prev, struct uhci_td, + list); + td = list_entry(urbp->td_list.prev, struct uhci_td, + list); + ptd->link = td->link; + goto done; + } + + /* If the QH element pointer is UHCI_PTR_TERM then then currently + * executing URB has already been unlinked, so this one isn't it. */ + if (qh_element(qh) == UHCI_PTR_TERM) + goto done; + qh->element = UHCI_PTR_TERM; + + /* Control pipes don't have to worry about toggles */ + if (qh->type == USB_ENDPOINT_XFER_CONTROL) + goto done; + + /* Save the next toggle value */ + WARN_ON(list_empty(&urbp->td_list)); + td = list_entry(urbp->td_list.next, struct uhci_td, list); + qh->needs_fixup = 1; + qh->initial_toggle = uhci_toggle(td_token(td)); + +done: + return ret; +} + +/* + * Fix up the data toggles for URBs in a queue, when one of them + * terminates early (short transfer, error, or dequeued). + */ +static void uhci_fixup_toggles(struct uhci_qh *qh, int skip_first) +{ + struct urb_priv *urbp = NULL; + struct uhci_td *td; + unsigned int toggle = qh->initial_toggle; + unsigned int pipe; + + /* Fixups for a short transfer start with the second URB in the + * queue (the short URB is the first). */ + if (skip_first) + urbp = list_entry(qh->queue.next, struct urb_priv, node); + + /* When starting with the first URB, if the QH element pointer is + * still valid then we know the URB's toggles are okay. */ + else if (qh_element(qh) != UHCI_PTR_TERM) + toggle = 2; + + /* Fix up the toggle for the URBs in the queue. Normally this + * loop won't run more than once: When an error or short transfer + * occurs, the queue usually gets emptied. */ + urbp = list_prepare_entry(urbp, &qh->queue, node); + list_for_each_entry_continue(urbp, &qh->queue, node) { + + /* If the first TD has the right toggle value, we don't + * need to change any toggles in this URB */ + td = list_entry(urbp->td_list.next, struct uhci_td, list); + if (toggle > 1 || uhci_toggle(td_token(td)) == toggle) { + td = list_entry(urbp->td_list.prev, struct uhci_td, + list); + toggle = uhci_toggle(td_token(td)) ^ 1; + + /* Otherwise all the toggles in the URB have to be switched */ + } else { + list_for_each_entry(td, &urbp->td_list, list) { + td->token ^= __constant_cpu_to_le32( + TD_TOKEN_TOGGLE); + toggle ^= 1; + } + } + } + + wmb(); + pipe = list_entry(qh->queue.next, struct urb_priv, node)->urb->pipe; + usb_settoggle(qh->udev, usb_pipeendpoint(pipe), + usb_pipeout(pipe), toggle); + qh->needs_fixup = 0; +} + +/* + * Link an Isochronous QH into its skeleton's list + */ +static inline void link_iso(struct uhci_hcd *uhci, struct uhci_qh *qh) +{ + list_add_tail(&qh->node, &uhci->skel_iso_qh->node); + + /* Isochronous QHs aren't linked by the hardware */ +} + +/* + * Link a high-period interrupt QH into the schedule at the end of its + * skeleton's list + */ +static void link_interrupt(struct uhci_hcd *uhci, struct uhci_qh *qh) +{ + struct uhci_qh *pqh; + + list_add_tail(&qh->node, &uhci->skelqh[qh->skel]->node); + + pqh = list_entry(qh->node.prev, struct uhci_qh, node); + qh->link = pqh->link; + wmb(); + pqh->link = LINK_TO_QH(qh); +} + +/* + * Link a period-1 interrupt or async QH into the schedule at the + * correct spot in the async skeleton's list, and update the FSBR link + */ +static void link_async(struct uhci_hcd *uhci, struct uhci_qh *qh) +{ + struct uhci_qh *pqh; + __le32 link_to_new_qh; + + /* Find the predecessor QH for our new one and insert it in the list. + * The list of QHs is expected to be short, so linear search won't + * take too long. */ + list_for_each_entry_reverse(pqh, &uhci->skel_async_qh->node, node) { + if (pqh->skel <= qh->skel) + break; + } + list_add(&qh->node, &pqh->node); + + /* Link it into the schedule */ + qh->link = pqh->link; + wmb(); + link_to_new_qh = LINK_TO_QH(qh); + pqh->link = link_to_new_qh; + + /* If this is now the first FSBR QH, link the terminating skeleton + * QH to it. */ + if (pqh->skel < SKEL_FSBR && qh->skel >= SKEL_FSBR) + uhci->skel_term_qh->link = link_to_new_qh; +} + +/* + * Put a QH on the schedule in both hardware and software + */ +static void uhci_activate_qh(struct uhci_hcd *uhci, struct uhci_qh *qh) +{ + WARN_ON(list_empty(&qh->queue)); + + /* Set the element pointer if it isn't set already. + * This isn't needed for Isochronous queues, but it doesn't hurt. */ + if (qh_element(qh) == UHCI_PTR_TERM) { + struct urb_priv *urbp = list_entry(qh->queue.next, + struct urb_priv, node); + struct uhci_td *td = list_entry(urbp->td_list.next, + struct uhci_td, list); + + qh->element = LINK_TO_TD(td); + } + + /* Treat the queue as if it has just advanced */ + qh->wait_expired = 0; + qh->advance_jiffies = jiffies; + + if (qh->state == QH_STATE_ACTIVE) + return; + qh->state = QH_STATE_ACTIVE; + + /* Move the QH from its old list to the correct spot in the appropriate + * skeleton's list */ + if (qh == uhci->next_qh) + uhci->next_qh = list_entry(qh->node.next, struct uhci_qh, + node); + list_del(&qh->node); + + if (qh->skel == SKEL_ISO) + link_iso(uhci, qh); + else if (qh->skel < SKEL_ASYNC) + link_interrupt(uhci, qh); + else + link_async(uhci, qh); +} + +/* + * Unlink a high-period interrupt QH from the schedule + */ +static void unlink_interrupt(struct uhci_hcd *uhci, struct uhci_qh *qh) +{ + struct uhci_qh *pqh; + + pqh = list_entry(qh->node.prev, struct uhci_qh, node); + pqh->link = qh->link; + mb(); +} + +/* + * Unlink a period-1 interrupt or async QH from the schedule + */ +static void unlink_async(struct uhci_hcd *uhci, struct uhci_qh *qh) +{ + struct uhci_qh *pqh; + __le32 link_to_next_qh = qh->link; + + pqh = list_entry(qh->node.prev, struct uhci_qh, node); + pqh->link = link_to_next_qh; + + /* If this was the old first FSBR QH, link the terminating skeleton + * QH to the next (new first FSBR) QH. */ + if (pqh->skel < SKEL_FSBR && qh->skel >= SKEL_FSBR) + uhci->skel_term_qh->link = link_to_next_qh; + mb(); +} + +/* + * Take a QH off the hardware schedule + */ +static void uhci_unlink_qh(struct uhci_hcd *uhci, struct uhci_qh *qh) +{ + if (qh->state == QH_STATE_UNLINKING) + return; + WARN_ON(qh->state != QH_STATE_ACTIVE || !qh->udev); + qh->state = QH_STATE_UNLINKING; + + /* Unlink the QH from the schedule and record when we did it */ + if (qh->skel == SKEL_ISO) + ; + else if (qh->skel < SKEL_ASYNC) + unlink_interrupt(uhci, qh); + else + unlink_async(uhci, qh); + + uhci_get_current_frame_number(uhci); + qh->unlink_frame = uhci->frame_number; + + /* Force an interrupt so we know when the QH is fully unlinked */ + if (list_empty(&uhci->skel_unlink_qh->node)) + uhci_set_next_interrupt(uhci); + + /* Move the QH from its old list to the end of the unlinking list */ + if (qh == uhci->next_qh) + uhci->next_qh = list_entry(qh->node.next, struct uhci_qh, + node); + list_move_tail(&qh->node, &uhci->skel_unlink_qh->node); +} + +/* + * When we and the controller are through with a QH, it becomes IDLE. + * This happens when a QH has been off the schedule (on the unlinking + * list) for more than one frame, or when an error occurs while adding + * the first URB onto a new QH. + */ +static void uhci_make_qh_idle(struct uhci_hcd *uhci, struct uhci_qh *qh) +{ + WARN_ON(qh->state == QH_STATE_ACTIVE); + + if (qh == uhci->next_qh) + uhci->next_qh = list_entry(qh->node.next, struct uhci_qh, + node); + list_move(&qh->node, &uhci->idle_qh_list); + qh->state = QH_STATE_IDLE; + + /* Now that the QH is idle, its post_td isn't being used */ + if (qh->post_td) { + uhci_free_td(uhci, qh->post_td); + qh->post_td = NULL; + } + + /* If anyone is waiting for a QH to become idle, wake them up */ + if (uhci->num_waiting) + wake_up_all(&uhci->waitqh); +} + +/* + * Find the highest existing bandwidth load for a given phase and period. + */ +static int uhci_highest_load(struct uhci_hcd *uhci, int phase, int period) +{ + int highest_load = uhci->load[phase]; + + for (phase += period; phase < MAX_PHASE; phase += period) + highest_load = max_t(int, highest_load, uhci->load[phase]); + return highest_load; +} + +/* + * Set qh->phase to the optimal phase for a periodic transfer and + * check whether the bandwidth requirement is acceptable. + */ +static int uhci_check_bandwidth(struct uhci_hcd *uhci, struct uhci_qh *qh) +{ + int minimax_load; + + /* Find the optimal phase (unless it is already set) and get + * its load value. */ + if (qh->phase >= 0) + minimax_load = uhci_highest_load(uhci, qh->phase, qh->period); + else { + int phase, load; + int max_phase = min_t(int, MAX_PHASE, qh->period); + + qh->phase = 0; + minimax_load = uhci_highest_load(uhci, qh->phase, qh->period); + for (phase = 1; phase < max_phase; ++phase) { + load = uhci_highest_load(uhci, phase, qh->period); + if (load < minimax_load) { + minimax_load = load; + qh->phase = phase; + } + } + } + + /* Maximum allowable periodic bandwidth is 90%, or 900 us per frame */ + if (minimax_load + qh->load > 900) { + dev_dbg(uhci_dev(uhci), "bandwidth allocation failed: " + "period %d, phase %d, %d + %d us\n", + qh->period, qh->phase, minimax_load, qh->load); + return -ENOSPC; + } + return 0; +} + +/* + * Reserve a periodic QH's bandwidth in the schedule + */ +static void uhci_reserve_bandwidth(struct uhci_hcd *uhci, struct uhci_qh *qh) +{ + int i; + int load = qh->load; + char *p = "??"; + + for (i = qh->phase; i < MAX_PHASE; i += qh->period) { + uhci->load[i] += load; + uhci->total_load += load; + } + uhci_to_hcd(uhci)->self.bandwidth_allocated = + uhci->total_load / MAX_PHASE; + switch (qh->type) { + case USB_ENDPOINT_XFER_INT: + ++uhci_to_hcd(uhci)->self.bandwidth_int_reqs; + p = "INT"; + break; + case USB_ENDPOINT_XFER_ISOC: + ++uhci_to_hcd(uhci)->self.bandwidth_isoc_reqs; + p = "ISO"; + break; + } + qh->bandwidth_reserved = 1; + dev_dbg(uhci_dev(uhci), + "%s dev %d ep%02x-%s, period %d, phase %d, %d us\n", + "reserve", qh->udev->devnum, + qh->hep->desc.bEndpointAddress, p, + qh->period, qh->phase, load); +} + +/* + * Release a periodic QH's bandwidth reservation + */ +static void uhci_release_bandwidth(struct uhci_hcd *uhci, struct uhci_qh *qh) +{ + int i; + int load = qh->load; + char *p = "??"; + + for (i = qh->phase; i < MAX_PHASE; i += qh->period) { + uhci->load[i] -= load; + uhci->total_load -= load; + } + uhci_to_hcd(uhci)->self.bandwidth_allocated = + uhci->total_load / MAX_PHASE; + switch (qh->type) { + case USB_ENDPOINT_XFER_INT: + --uhci_to_hcd(uhci)->self.bandwidth_int_reqs; + p = "INT"; + break; + case USB_ENDPOINT_XFER_ISOC: + --uhci_to_hcd(uhci)->self.bandwidth_isoc_reqs; + p = "ISO"; + break; + } + qh->bandwidth_reserved = 0; + dev_dbg(uhci_dev(uhci), + "%s dev %d ep%02x-%s, period %d, phase %d, %d us\n", + "release", qh->udev->devnum, + qh->hep->desc.bEndpointAddress, p, + qh->period, qh->phase, load); +} + +static inline struct urb_priv *uhci_alloc_urb_priv(struct uhci_hcd *uhci, + struct urb *urb) +{ + struct urb_priv *urbp; + + urbp = kmem_cache_zalloc(uhci_up_cachep, GFP_ATOMIC); + if (!urbp) + return NULL; + + urbp->urb = urb; + urb->hcpriv = urbp; + + INIT_LIST_HEAD(&urbp->node); + INIT_LIST_HEAD(&urbp->td_list); + + return urbp; +} + +static void uhci_free_urb_priv(struct uhci_hcd *uhci, + struct urb_priv *urbp) +{ + struct uhci_td *td, *tmp; + + if (!list_empty(&urbp->node)) + dev_WARN(uhci_dev(uhci), "urb %p still on QH's list!\n", + urbp->urb); + + list_for_each_entry_safe(td, tmp, &urbp->td_list, list) { + uhci_remove_td_from_urbp(td); + uhci_free_td(uhci, td); + } + + kmem_cache_free(uhci_up_cachep, urbp); +} + +/* + * Map status to standard result codes + * + * <status> is (td_status(td) & 0xF60000), a.k.a. + * uhci_status_bits(td_status(td)). + * Note: <status> does not include the TD_CTRL_NAK bit. + * <dir_out> is True for output TDs and False for input TDs. + */ +static int uhci_map_status(int status, int dir_out) +{ + if (!status) + return 0; + if (status & TD_CTRL_BITSTUFF) /* Bitstuff error */ + return -EPROTO; + if (status & TD_CTRL_CRCTIMEO) { /* CRC/Timeout */ + if (dir_out) + return -EPROTO; + else + return -EILSEQ; + } + if (status & TD_CTRL_BABBLE) /* Babble */ + return -EOVERFLOW; + if (status & TD_CTRL_DBUFERR) /* Buffer error */ + return -ENOSR; + if (status & TD_CTRL_STALLED) /* Stalled */ + return -EPIPE; + return 0; +} + +/* + * Control transfers + */ +static int uhci_submit_control(struct uhci_hcd *uhci, struct urb *urb, + struct uhci_qh *qh) +{ + struct uhci_td *td; + unsigned long destination, status; + int maxsze = le16_to_cpu(qh->hep->desc.wMaxPacketSize); + int len = urb->transfer_buffer_length; + dma_addr_t data = urb->transfer_dma; + __le32 *plink; + struct urb_priv *urbp = urb->hcpriv; + int skel; + + /* The "pipe" thing contains the destination in bits 8--18 */ + destination = (urb->pipe & PIPE_DEVEP_MASK) | USB_PID_SETUP; + + /* 3 errors, dummy TD remains inactive */ + status = uhci_maxerr(3); + if (urb->dev->speed == USB_SPEED_LOW) + status |= TD_CTRL_LS; + + /* + * Build the TD for the control request setup packet + */ + td = qh->dummy_td; + uhci_add_td_to_urbp(td, urbp); + uhci_fill_td(td, status, destination | uhci_explen(8), + urb->setup_dma); + plink = &td->link; + status |= TD_CTRL_ACTIVE; + + /* + * If direction is "send", change the packet ID from SETUP (0x2D) + * to OUT (0xE1). Else change it from SETUP to IN (0x69) and + * set Short Packet Detect (SPD) for all data packets. + * + * 0-length transfers always get treated as "send". + */ + if (usb_pipeout(urb->pipe) || len == 0) + destination ^= (USB_PID_SETUP ^ USB_PID_OUT); + else { + destination ^= (USB_PID_SETUP ^ USB_PID_IN); + status |= TD_CTRL_SPD; + } + + /* + * Build the DATA TDs + */ + while (len > 0) { + int pktsze = maxsze; + + if (len <= pktsze) { /* The last data packet */ + pktsze = len; + status &= ~TD_CTRL_SPD; + } + + td = uhci_alloc_td(uhci); + if (!td) + goto nomem; + *plink = LINK_TO_TD(td); + + /* Alternate Data0/1 (start with Data1) */ + destination ^= TD_TOKEN_TOGGLE; + + uhci_add_td_to_urbp(td, urbp); + uhci_fill_td(td, status, destination | uhci_explen(pktsze), + data); + plink = &td->link; + + data += pktsze; + len -= pktsze; + } + + /* + * Build the final TD for control status + */ + td = uhci_alloc_td(uhci); + if (!td) + goto nomem; + *plink = LINK_TO_TD(td); + + /* Change direction for the status transaction */ + destination ^= (USB_PID_IN ^ USB_PID_OUT); + destination |= TD_TOKEN_TOGGLE; /* End in Data1 */ + + uhci_add_td_to_urbp(td, urbp); + uhci_fill_td(td, status | TD_CTRL_IOC, + destination | uhci_explen(0), 0); + plink = &td->link; + + /* + * Build the new dummy TD and activate the old one + */ + td = uhci_alloc_td(uhci); + if (!td) + goto nomem; + *plink = LINK_TO_TD(td); + + uhci_fill_td(td, 0, USB_PID_OUT | uhci_explen(0), 0); + wmb(); + qh->dummy_td->status |= __constant_cpu_to_le32(TD_CTRL_ACTIVE); + qh->dummy_td = td; + + /* Low-speed transfers get a different queue, and won't hog the bus. + * Also, some devices enumerate better without FSBR; the easiest way + * to do that is to put URBs on the low-speed queue while the device + * isn't in the CONFIGURED state. */ + if (urb->dev->speed == USB_SPEED_LOW || + urb->dev->state != USB_STATE_CONFIGURED) + skel = SKEL_LS_CONTROL; + else { + skel = SKEL_FS_CONTROL; + uhci_add_fsbr(uhci, urb); + } + if (qh->state != QH_STATE_ACTIVE) + qh->skel = skel; + + urb->actual_length = -8; /* Account for the SETUP packet */ + return 0; + +nomem: + /* Remove the dummy TD from the td_list so it doesn't get freed */ + uhci_remove_td_from_urbp(qh->dummy_td); + return -ENOMEM; +} + +/* + * Common submit for bulk and interrupt + */ +static int uhci_submit_common(struct uhci_hcd *uhci, struct urb *urb, + struct uhci_qh *qh) +{ + struct uhci_td *td; + unsigned long destination, status; + int maxsze = le16_to_cpu(qh->hep->desc.wMaxPacketSize); + int len = urb->transfer_buffer_length; + dma_addr_t data = urb->transfer_dma; + __le32 *plink; + struct urb_priv *urbp = urb->hcpriv; + unsigned int toggle; + + if (len < 0) + return -EINVAL; + + /* The "pipe" thing contains the destination in bits 8--18 */ + destination = (urb->pipe & PIPE_DEVEP_MASK) | usb_packetid(urb->pipe); + toggle = usb_gettoggle(urb->dev, usb_pipeendpoint(urb->pipe), + usb_pipeout(urb->pipe)); + + /* 3 errors, dummy TD remains inactive */ + status = uhci_maxerr(3); + if (urb->dev->speed == USB_SPEED_LOW) + status |= TD_CTRL_LS; + if (usb_pipein(urb->pipe)) + status |= TD_CTRL_SPD; + + /* + * Build the DATA TDs + */ + plink = NULL; + td = qh->dummy_td; + do { /* Allow zero length packets */ + int pktsze = maxsze; + + if (len <= pktsze) { /* The last packet */ + pktsze = len; + if (!(urb->transfer_flags & URB_SHORT_NOT_OK)) + status &= ~TD_CTRL_SPD; + } + + if (plink) { + td = uhci_alloc_td(uhci); + if (!td) + goto nomem; + *plink = LINK_TO_TD(td); + } + uhci_add_td_to_urbp(td, urbp); + uhci_fill_td(td, status, + destination | uhci_explen(pktsze) | + (toggle << TD_TOKEN_TOGGLE_SHIFT), + data); + plink = &td->link; + status |= TD_CTRL_ACTIVE; + + data += pktsze; + len -= maxsze; + toggle ^= 1; + } while (len > 0); + + /* + * URB_ZERO_PACKET means adding a 0-length packet, if direction + * is OUT and the transfer_length was an exact multiple of maxsze, + * hence (len = transfer_length - N * maxsze) == 0 + * however, if transfer_length == 0, the zero packet was already + * prepared above. + */ + if ((urb->transfer_flags & URB_ZERO_PACKET) && + usb_pipeout(urb->pipe) && len == 0 && + urb->transfer_buffer_length > 0) { + td = uhci_alloc_td(uhci); + if (!td) + goto nomem; + *plink = LINK_TO_TD(td); + + uhci_add_td_to_urbp(td, urbp); + uhci_fill_td(td, status, + destination | uhci_explen(0) | + (toggle << TD_TOKEN_TOGGLE_SHIFT), + data); + plink = &td->link; + + toggle ^= 1; + } + + /* Set the interrupt-on-completion flag on the last packet. + * A more-or-less typical 4 KB URB (= size of one memory page) + * will require about 3 ms to transfer; that's a little on the + * fast side but not enough to justify delaying an interrupt + * more than 2 or 3 URBs, so we will ignore the URB_NO_INTERRUPT + * flag setting. */ + td->status |= __constant_cpu_to_le32(TD_CTRL_IOC); + + /* + * Build the new dummy TD and activate the old one + */ + td = uhci_alloc_td(uhci); + if (!td) + goto nomem; + *plink = LINK_TO_TD(td); + + uhci_fill_td(td, 0, USB_PID_OUT | uhci_explen(0), 0); + wmb(); + qh->dummy_td->status |= __constant_cpu_to_le32(TD_CTRL_ACTIVE); + qh->dummy_td = td; + + usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe), + usb_pipeout(urb->pipe), toggle); + return 0; + +nomem: + /* Remove the dummy TD from the td_list so it doesn't get freed */ + uhci_remove_td_from_urbp(qh->dummy_td); + return -ENOMEM; +} + +static int uhci_submit_bulk(struct uhci_hcd *uhci, struct urb *urb, + struct uhci_qh *qh) +{ + int ret; + + /* Can't have low-speed bulk transfers */ + if (urb->dev->speed == USB_SPEED_LOW) + return -EINVAL; + + if (qh->state != QH_STATE_ACTIVE) + qh->skel = SKEL_BULK; + ret = uhci_submit_common(uhci, urb, qh); + if (ret == 0) + uhci_add_fsbr(uhci, urb); + return ret; +} + +static int uhci_submit_interrupt(struct uhci_hcd *uhci, struct urb *urb, + struct uhci_qh *qh) +{ + int ret; + + /* USB 1.1 interrupt transfers only involve one packet per interval. + * Drivers can submit URBs of any length, but longer ones will need + * multiple intervals to complete. + */ + + if (!qh->bandwidth_reserved) { + int exponent; + + /* Figure out which power-of-two queue to use */ + for (exponent = 7; exponent >= 0; --exponent) { + if ((1 << exponent) <= urb->interval) + break; + } + if (exponent < 0) + return -EINVAL; + + /* If the slot is full, try a lower period */ + do { + qh->period = 1 << exponent; + qh->skel = SKEL_INDEX(exponent); + + /* For now, interrupt phase is fixed by the layout + * of the QH lists. + */ + qh->phase = (qh->period / 2) & (MAX_PHASE - 1); + ret = uhci_check_bandwidth(uhci, qh); + } while (ret != 0 && --exponent >= 0); + if (ret) + return ret; + } else if (qh->period > urb->interval) + return -EINVAL; /* Can't decrease the period */ + + ret = uhci_submit_common(uhci, urb, qh); + if (ret == 0) { + urb->interval = qh->period; + if (!qh->bandwidth_reserved) + uhci_reserve_bandwidth(uhci, qh); + } + return ret; +} + +/* + * Fix up the data structures following a short transfer + */ +static int uhci_fixup_short_transfer(struct uhci_hcd *uhci, + struct uhci_qh *qh, struct urb_priv *urbp) +{ + struct uhci_td *td; + struct list_head *tmp; + int ret; + + td = list_entry(urbp->td_list.prev, struct uhci_td, list); + if (qh->type == USB_ENDPOINT_XFER_CONTROL) { + + /* When a control transfer is short, we have to restart + * the queue at the status stage transaction, which is + * the last TD. */ + WARN_ON(list_empty(&urbp->td_list)); + qh->element = LINK_TO_TD(td); + tmp = td->list.prev; + ret = -EINPROGRESS; + + } else { + + /* When a bulk/interrupt transfer is short, we have to + * fix up the toggles of the following URBs on the queue + * before restarting the queue at the next URB. */ + qh->initial_toggle = uhci_toggle(td_token(qh->post_td)) ^ 1; + uhci_fixup_toggles(qh, 1); + + if (list_empty(&urbp->td_list)) + td = qh->post_td; + qh->element = td->link; + tmp = urbp->td_list.prev; + ret = 0; + } + + /* Remove all the TDs we skipped over, from tmp back to the start */ + while (tmp != &urbp->td_list) { + td = list_entry(tmp, struct uhci_td, list); + tmp = tmp->prev; + + uhci_remove_td_from_urbp(td); + uhci_free_td(uhci, td); + } + return ret; +} + +/* + * Common result for control, bulk, and interrupt + */ +static int uhci_result_common(struct uhci_hcd *uhci, struct urb *urb) +{ + struct urb_priv *urbp = urb->hcpriv; + struct uhci_qh *qh = urbp->qh; + struct uhci_td *td, *tmp; + unsigned status; + int ret = 0; + + list_for_each_entry_safe(td, tmp, &urbp->td_list, list) { + unsigned int ctrlstat; + int len; + + ctrlstat = td_status(td); + status = uhci_status_bits(ctrlstat); + if (status & TD_CTRL_ACTIVE) + return -EINPROGRESS; + + len = uhci_actual_length(ctrlstat); + urb->actual_length += len; + + if (status) { + ret = uhci_map_status(status, + uhci_packetout(td_token(td))); + if ((debug == 1 && ret != -EPIPE) || debug > 1) { + /* Some debugging code */ + dev_dbg(&urb->dev->dev, + "%s: failed with status %x\n", + __func__, status); + + if (debug > 1 && errbuf) { + /* Print the chain for debugging */ + uhci_show_qh(uhci, urbp->qh, errbuf, + ERRBUF_LEN, 0); + lprintk(errbuf); + } + } + + /* Did we receive a short packet? */ + } else if (len < uhci_expected_length(td_token(td))) { + + /* For control transfers, go to the status TD if + * this isn't already the last data TD */ + if (qh->type == USB_ENDPOINT_XFER_CONTROL) { + if (td->list.next != urbp->td_list.prev) + ret = 1; + } + + /* For bulk and interrupt, this may be an error */ + else if (urb->transfer_flags & URB_SHORT_NOT_OK) + ret = -EREMOTEIO; + + /* Fixup needed only if this isn't the URB's last TD */ + else if (&td->list != urbp->td_list.prev) + ret = 1; + } + + uhci_remove_td_from_urbp(td); + if (qh->post_td) + uhci_free_td(uhci, qh->post_td); + qh->post_td = td; + + if (ret != 0) + goto err; + } + return ret; + +err: + if (ret < 0) { + /* Note that the queue has stopped and save + * the next toggle value */ + qh->element = UHCI_PTR_TERM; + qh->is_stopped = 1; + qh->needs_fixup = (qh->type != USB_ENDPOINT_XFER_CONTROL); + qh->initial_toggle = uhci_toggle(td_token(td)) ^ + (ret == -EREMOTEIO); + + } else /* Short packet received */ + ret = uhci_fixup_short_transfer(uhci, qh, urbp); + return ret; +} + +/* + * Isochronous transfers + */ +static int uhci_submit_isochronous(struct uhci_hcd *uhci, struct urb *urb, + struct uhci_qh *qh) +{ + struct uhci_td *td = NULL; /* Since urb->number_of_packets > 0 */ + int i, frame; + unsigned long destination, status; + struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv; + + /* Values must not be too big (could overflow below) */ + if (urb->interval >= UHCI_NUMFRAMES || + urb->number_of_packets >= UHCI_NUMFRAMES) + return -EFBIG; + + /* Check the period and figure out the starting frame number */ + if (!qh->bandwidth_reserved) { + qh->period = urb->interval; + if (urb->transfer_flags & URB_ISO_ASAP) { + qh->phase = -1; /* Find the best phase */ + i = uhci_check_bandwidth(uhci, qh); + if (i) + return i; + + /* Allow a little time to allocate the TDs */ + uhci_get_current_frame_number(uhci); + frame = uhci->frame_number + 10; + + /* Move forward to the first frame having the + * correct phase */ + urb->start_frame = frame + ((qh->phase - frame) & + (qh->period - 1)); + } else { + i = urb->start_frame - uhci->last_iso_frame; + if (i <= 0 || i >= UHCI_NUMFRAMES) + return -EINVAL; + qh->phase = urb->start_frame & (qh->period - 1); + i = uhci_check_bandwidth(uhci, qh); + if (i) + return i; + } + + } else if (qh->period != urb->interval) { + return -EINVAL; /* Can't change the period */ + + } else { + /* Find the next unused frame */ + if (list_empty(&qh->queue)) { + frame = qh->iso_frame; + } else { + struct urb *lurb; + + lurb = list_entry(qh->queue.prev, + struct urb_priv, node)->urb; + frame = lurb->start_frame + + lurb->number_of_packets * + lurb->interval; + } + if (urb->transfer_flags & URB_ISO_ASAP) { + /* Skip some frames if necessary to insure + * the start frame is in the future. + */ + uhci_get_current_frame_number(uhci); + if (uhci_frame_before_eq(frame, uhci->frame_number)) { + frame = uhci->frame_number + 1; + frame += ((qh->phase - frame) & + (qh->period - 1)); + } + } /* Otherwise pick up where the last URB leaves off */ + urb->start_frame = frame; + } + + /* Make sure we won't have to go too far into the future */ + if (uhci_frame_before_eq(uhci->last_iso_frame + UHCI_NUMFRAMES, + urb->start_frame + urb->number_of_packets * + urb->interval)) + return -EFBIG; + + status = TD_CTRL_ACTIVE | TD_CTRL_IOS; + destination = (urb->pipe & PIPE_DEVEP_MASK) | usb_packetid(urb->pipe); + + for (i = 0; i < urb->number_of_packets; i++) { + td = uhci_alloc_td(uhci); + if (!td) + return -ENOMEM; + + uhci_add_td_to_urbp(td, urbp); + uhci_fill_td(td, status, destination | + uhci_explen(urb->iso_frame_desc[i].length), + urb->transfer_dma + + urb->iso_frame_desc[i].offset); + } + + /* Set the interrupt-on-completion flag on the last packet. */ + td->status |= __constant_cpu_to_le32(TD_CTRL_IOC); + + /* Add the TDs to the frame list */ + frame = urb->start_frame; + list_for_each_entry(td, &urbp->td_list, list) { + uhci_insert_td_in_frame_list(uhci, td, frame); + frame += qh->period; + } + + if (list_empty(&qh->queue)) { + qh->iso_packet_desc = &urb->iso_frame_desc[0]; + qh->iso_frame = urb->start_frame; + } + + qh->skel = SKEL_ISO; + if (!qh->bandwidth_reserved) + uhci_reserve_bandwidth(uhci, qh); + return 0; +} + +static int uhci_result_isochronous(struct uhci_hcd *uhci, struct urb *urb) +{ + struct uhci_td *td, *tmp; + struct urb_priv *urbp = urb->hcpriv; + struct uhci_qh *qh = urbp->qh; + + list_for_each_entry_safe(td, tmp, &urbp->td_list, list) { + unsigned int ctrlstat; + int status; + int actlength; + + if (uhci_frame_before_eq(uhci->cur_iso_frame, qh->iso_frame)) + return -EINPROGRESS; + + uhci_remove_tds_from_frame(uhci, qh->iso_frame); + + ctrlstat = td_status(td); + if (ctrlstat & TD_CTRL_ACTIVE) { + status = -EXDEV; /* TD was added too late? */ + } else { + status = uhci_map_status(uhci_status_bits(ctrlstat), + usb_pipeout(urb->pipe)); + actlength = uhci_actual_length(ctrlstat); + + urb->actual_length += actlength; + qh->iso_packet_desc->actual_length = actlength; + qh->iso_packet_desc->status = status; + } + if (status) + urb->error_count++; + + uhci_remove_td_from_urbp(td); + uhci_free_td(uhci, td); + qh->iso_frame += qh->period; + ++qh->iso_packet_desc; + } + return 0; +} + +static int uhci_urb_enqueue(struct usb_hcd *hcd, + struct urb *urb, gfp_t mem_flags) +{ + int ret; + struct uhci_hcd *uhci = hcd_to_uhci(hcd); + unsigned long flags; + struct urb_priv *urbp; + struct uhci_qh *qh; + + spin_lock_irqsave(&uhci->lock, flags); + + ret = usb_hcd_link_urb_to_ep(hcd, urb); + if (ret) + goto done_not_linked; + + ret = -ENOMEM; + urbp = uhci_alloc_urb_priv(uhci, urb); + if (!urbp) + goto done; + + if (urb->ep->hcpriv) + qh = urb->ep->hcpriv; + else { + qh = uhci_alloc_qh(uhci, urb->dev, urb->ep); + if (!qh) + goto err_no_qh; + } + urbp->qh = qh; + + switch (qh->type) { + case USB_ENDPOINT_XFER_CONTROL: + ret = uhci_submit_control(uhci, urb, qh); + break; + case USB_ENDPOINT_XFER_BULK: + ret = uhci_submit_bulk(uhci, urb, qh); + break; + case USB_ENDPOINT_XFER_INT: + ret = uhci_submit_interrupt(uhci, urb, qh); + break; + case USB_ENDPOINT_XFER_ISOC: + urb->error_count = 0; + ret = uhci_submit_isochronous(uhci, urb, qh); + break; + } + if (ret != 0) + goto err_submit_failed; + + /* Add this URB to the QH */ + urbp->qh = qh; + list_add_tail(&urbp->node, &qh->queue); + + /* If the new URB is the first and only one on this QH then either + * the QH is new and idle or else it's unlinked and waiting to + * become idle, so we can activate it right away. But only if the + * queue isn't stopped. */ + if (qh->queue.next == &urbp->node && !qh->is_stopped) { + uhci_activate_qh(uhci, qh); + uhci_urbp_wants_fsbr(uhci, urbp); + } + goto done; + +err_submit_failed: + if (qh->state == QH_STATE_IDLE) + uhci_make_qh_idle(uhci, qh); /* Reclaim unused QH */ +err_no_qh: + uhci_free_urb_priv(uhci, urbp); +done: + if (ret) + usb_hcd_unlink_urb_from_ep(hcd, urb); +done_not_linked: + spin_unlock_irqrestore(&uhci->lock, flags); + return ret; +} + +static int uhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status) +{ + struct uhci_hcd *uhci = hcd_to_uhci(hcd); + unsigned long flags; + struct uhci_qh *qh; + int rc; + + spin_lock_irqsave(&uhci->lock, flags); + rc = usb_hcd_check_unlink_urb(hcd, urb, status); + if (rc) + goto done; + + qh = ((struct urb_priv *) urb->hcpriv)->qh; + + /* Remove Isochronous TDs from the frame list ASAP */ + if (qh->type == USB_ENDPOINT_XFER_ISOC) { + uhci_unlink_isochronous_tds(uhci, urb); + mb(); + + /* If the URB has already started, update the QH unlink time */ + uhci_get_current_frame_number(uhci); + if (uhci_frame_before_eq(urb->start_frame, uhci->frame_number)) + qh->unlink_frame = uhci->frame_number; + } + + uhci_unlink_qh(uhci, qh); + +done: + spin_unlock_irqrestore(&uhci->lock, flags); + return rc; +} + +/* + * Finish unlinking an URB and give it back + */ +static void uhci_giveback_urb(struct uhci_hcd *uhci, struct uhci_qh *qh, + struct urb *urb, int status) +__releases(uhci->lock) +__acquires(uhci->lock) +{ + struct urb_priv *urbp = (struct urb_priv *) urb->hcpriv; + + if (qh->type == USB_ENDPOINT_XFER_CONTROL) { + + /* urb->actual_length < 0 means the setup transaction didn't + * complete successfully. Either it failed or the URB was + * unlinked first. Regardless, don't confuse people with a + * negative length. */ + urb->actual_length = max(urb->actual_length, 0); + } + + /* When giving back the first URB in an Isochronous queue, + * reinitialize the QH's iso-related members for the next URB. */ + else if (qh->type == USB_ENDPOINT_XFER_ISOC && + urbp->node.prev == &qh->queue && + urbp->node.next != &qh->queue) { + struct urb *nurb = list_entry(urbp->node.next, + struct urb_priv, node)->urb; + + qh->iso_packet_desc = &nurb->iso_frame_desc[0]; + qh->iso_frame = nurb->start_frame; + } + + /* Take the URB off the QH's queue. If the queue is now empty, + * this is a perfect time for a toggle fixup. */ + list_del_init(&urbp->node); + if (list_empty(&qh->queue) && qh->needs_fixup) { + usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe), + usb_pipeout(urb->pipe), qh->initial_toggle); + qh->needs_fixup = 0; + } + + uhci_free_urb_priv(uhci, urbp); + usb_hcd_unlink_urb_from_ep(uhci_to_hcd(uhci), urb); + + spin_unlock(&uhci->lock); + usb_hcd_giveback_urb(uhci_to_hcd(uhci), urb, status); + spin_lock(&uhci->lock); + + /* If the queue is now empty, we can unlink the QH and give up its + * reserved bandwidth. */ + if (list_empty(&qh->queue)) { + uhci_unlink_qh(uhci, qh); + if (qh->bandwidth_reserved) + uhci_release_bandwidth(uhci, qh); + } +} + +/* + * Scan the URBs in a QH's queue + */ +#define QH_FINISHED_UNLINKING(qh) \ + (qh->state == QH_STATE_UNLINKING && \ + uhci->frame_number + uhci->is_stopped != qh->unlink_frame) + +static void uhci_scan_qh(struct uhci_hcd *uhci, struct uhci_qh *qh) +{ + struct urb_priv *urbp; + struct urb *urb; + int status; + + while (!list_empty(&qh->queue)) { + urbp = list_entry(qh->queue.next, struct urb_priv, node); + urb = urbp->urb; + + if (qh->type == USB_ENDPOINT_XFER_ISOC) + status = uhci_result_isochronous(uhci, urb); + else + status = uhci_result_common(uhci, urb); + if (status == -EINPROGRESS) + break; + + /* Dequeued but completed URBs can't be given back unless + * the QH is stopped or has finished unlinking. */ + if (urb->unlinked) { + if (QH_FINISHED_UNLINKING(qh)) + qh->is_stopped = 1; + else if (!qh->is_stopped) + return; + } + + uhci_giveback_urb(uhci, qh, urb, status); + if (status < 0) + break; + } + + /* If the QH is neither stopped nor finished unlinking (normal case), + * our work here is done. */ + if (QH_FINISHED_UNLINKING(qh)) + qh->is_stopped = 1; + else if (!qh->is_stopped) + return; + + /* Otherwise give back each of the dequeued URBs */ +restart: + list_for_each_entry(urbp, &qh->queue, node) { + urb = urbp->urb; + if (urb->unlinked) { + + /* Fix up the TD links and save the toggles for + * non-Isochronous queues. For Isochronous queues, + * test for too-recent dequeues. */ + if (!uhci_cleanup_queue(uhci, qh, urb)) { + qh->is_stopped = 0; + return; + } + uhci_giveback_urb(uhci, qh, urb, 0); + goto restart; + } + } + qh->is_stopped = 0; + + /* There are no more dequeued URBs. If there are still URBs on the + * queue, the QH can now be re-activated. */ + if (!list_empty(&qh->queue)) { + if (qh->needs_fixup) + uhci_fixup_toggles(qh, 0); + + /* If the first URB on the queue wants FSBR but its time + * limit has expired, set the next TD to interrupt on + * completion before reactivating the QH. */ + urbp = list_entry(qh->queue.next, struct urb_priv, node); + if (urbp->fsbr && qh->wait_expired) { + struct uhci_td *td = list_entry(urbp->td_list.next, + struct uhci_td, list); + + td->status |= __cpu_to_le32(TD_CTRL_IOC); + } + + uhci_activate_qh(uhci, qh); + } + + /* The queue is empty. The QH can become idle if it is fully + * unlinked. */ + else if (QH_FINISHED_UNLINKING(qh)) + uhci_make_qh_idle(uhci, qh); +} + +/* + * Check for queues that have made some forward progress. + * Returns 0 if the queue is not Isochronous, is ACTIVE, and + * has not advanced since last examined; 1 otherwise. + * + * Early Intel controllers have a bug which causes qh->element sometimes + * not to advance when a TD completes successfully. The queue remains + * stuck on the inactive completed TD. We detect such cases and advance + * the element pointer by hand. + */ +static int uhci_advance_check(struct uhci_hcd *uhci, struct uhci_qh *qh) +{ + struct urb_priv *urbp = NULL; + struct uhci_td *td; + int ret = 1; + unsigned status; + + if (qh->type == USB_ENDPOINT_XFER_ISOC) + goto done; + + /* Treat an UNLINKING queue as though it hasn't advanced. + * This is okay because reactivation will treat it as though + * it has advanced, and if it is going to become IDLE then + * this doesn't matter anyway. Furthermore it's possible + * for an UNLINKING queue not to have any URBs at all, or + * for its first URB not to have any TDs (if it was dequeued + * just as it completed). So it's not easy in any case to + * test whether such queues have advanced. */ + if (qh->state != QH_STATE_ACTIVE) { + urbp = NULL; + status = 0; + + } else { + urbp = list_entry(qh->queue.next, struct urb_priv, node); + td = list_entry(urbp->td_list.next, struct uhci_td, list); + status = td_status(td); + if (!(status & TD_CTRL_ACTIVE)) { + + /* We're okay, the queue has advanced */ + qh->wait_expired = 0; + qh->advance_jiffies = jiffies; + goto done; + } + ret = 0; + } + + /* The queue hasn't advanced; check for timeout */ + if (qh->wait_expired) + goto done; + + if (time_after(jiffies, qh->advance_jiffies + QH_WAIT_TIMEOUT)) { + + /* Detect the Intel bug and work around it */ + if (qh->post_td && qh_element(qh) == LINK_TO_TD(qh->post_td)) { + qh->element = qh->post_td->link; + qh->advance_jiffies = jiffies; + ret = 1; + goto done; + } + + qh->wait_expired = 1; + + /* If the current URB wants FSBR, unlink it temporarily + * so that we can safely set the next TD to interrupt on + * completion. That way we'll know as soon as the queue + * starts moving again. */ + if (urbp && urbp->fsbr && !(status & TD_CTRL_IOC)) + uhci_unlink_qh(uhci, qh); + + } else { + /* Unmoving but not-yet-expired queues keep FSBR alive */ + if (urbp) + uhci_urbp_wants_fsbr(uhci, urbp); + } + +done: + return ret; +} + +/* + * Process events in the schedule, but only in one thread at a time + */ +static void uhci_scan_schedule(struct uhci_hcd *uhci) +{ + int i; + struct uhci_qh *qh; + + /* Don't allow re-entrant calls */ + if (uhci->scan_in_progress) { + uhci->need_rescan = 1; + return; + } + uhci->scan_in_progress = 1; +rescan: + uhci->need_rescan = 0; + uhci->fsbr_is_wanted = 0; + + uhci_clear_next_interrupt(uhci); + uhci_get_current_frame_number(uhci); + uhci->cur_iso_frame = uhci->frame_number; + + /* Go through all the QH queues and process the URBs in each one */ + for (i = 0; i < UHCI_NUM_SKELQH - 1; ++i) { + uhci->next_qh = list_entry(uhci->skelqh[i]->node.next, + struct uhci_qh, node); + while ((qh = uhci->next_qh) != uhci->skelqh[i]) { + uhci->next_qh = list_entry(qh->node.next, + struct uhci_qh, node); + + if (uhci_advance_check(uhci, qh)) { + uhci_scan_qh(uhci, qh); + if (qh->state == QH_STATE_ACTIVE) { + uhci_urbp_wants_fsbr(uhci, + list_entry(qh->queue.next, struct urb_priv, node)); + } + } + } + } + + uhci->last_iso_frame = uhci->cur_iso_frame; + if (uhci->need_rescan) + goto rescan; + uhci->scan_in_progress = 0; + + if (uhci->fsbr_is_on && !uhci->fsbr_is_wanted && + !uhci->fsbr_expiring) { + uhci->fsbr_expiring = 1; + mod_timer(&uhci->fsbr_timer, jiffies + FSBR_OFF_DELAY); + } + + if (list_empty(&uhci->skel_unlink_qh->node)) + uhci_clear_next_interrupt(uhci); + else + uhci_set_next_interrupt(uhci); +} |
