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WSL2-Linux-Kernel
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WSL2-Linux-Kernel/drivers/usb/host/uhci-q.c

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46 KiB
C
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/*
* 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);
}
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