aboutsummaryrefslogtreecommitdiff
path: root/drivers/usb/host/ohci-q.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /drivers/usb/host/ohci-q.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'drivers/usb/host/ohci-q.c')
-rw-r--r--drivers/usb/host/ohci-q.c1107
1 files changed, 1107 insertions, 0 deletions
diff --git a/drivers/usb/host/ohci-q.c b/drivers/usb/host/ohci-q.c
new file mode 100644
index 00000000000..c90114a7727
--- /dev/null
+++ b/drivers/usb/host/ohci-q.c
@@ -0,0 +1,1107 @@
+/*
+ * OHCI HCD (Host Controller Driver) for USB.
+ *
+ * (C) Copyright 1999 Roman Weissgaerber <weissg@vienna.at>
+ * (C) Copyright 2000-2002 David Brownell <dbrownell@users.sourceforge.net>
+ *
+ * This file is licenced under the GPL.
+ */
+
+static void urb_free_priv (struct ohci_hcd *hc, urb_priv_t *urb_priv)
+{
+ int last = urb_priv->length - 1;
+
+ if (last >= 0) {
+ int i;
+ struct td *td;
+
+ for (i = 0; i <= last; i++) {
+ td = urb_priv->td [i];
+ if (td)
+ td_free (hc, td);
+ }
+ }
+
+ list_del (&urb_priv->pending);
+ kfree (urb_priv);
+}
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * URB goes back to driver, and isn't reissued.
+ * It's completely gone from HC data structures.
+ * PRECONDITION: ohci lock held, irqs blocked.
+ */
+static void
+finish_urb (struct ohci_hcd *ohci, struct urb *urb, struct pt_regs *regs)
+__releases(ohci->lock)
+__acquires(ohci->lock)
+{
+ // ASSERT (urb->hcpriv != 0);
+
+ urb_free_priv (ohci, urb->hcpriv);
+ urb->hcpriv = NULL;
+
+ spin_lock (&urb->lock);
+ if (likely (urb->status == -EINPROGRESS))
+ urb->status = 0;
+ /* report short control reads right even though the data TD always
+ * has TD_R set. (much simpler, but creates the 1-td limit.)
+ */
+ if (unlikely (urb->transfer_flags & URB_SHORT_NOT_OK)
+ && unlikely (usb_pipecontrol (urb->pipe))
+ && urb->actual_length < urb->transfer_buffer_length
+ && usb_pipein (urb->pipe)
+ && urb->status == 0) {
+ urb->status = -EREMOTEIO;
+ }
+ spin_unlock (&urb->lock);
+
+ switch (usb_pipetype (urb->pipe)) {
+ case PIPE_ISOCHRONOUS:
+ ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs--;
+ break;
+ case PIPE_INTERRUPT:
+ ohci_to_hcd(ohci)->self.bandwidth_int_reqs--;
+ break;
+ }
+
+#ifdef OHCI_VERBOSE_DEBUG
+ urb_print (urb, "RET", usb_pipeout (urb->pipe));
+#endif
+
+ /* urb->complete() can reenter this HCD */
+ spin_unlock (&ohci->lock);
+ usb_hcd_giveback_urb (ohci_to_hcd(ohci), urb, regs);
+ spin_lock (&ohci->lock);
+
+ /* stop periodic dma if it's not needed */
+ if (ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs == 0
+ && ohci_to_hcd(ohci)->self.bandwidth_int_reqs == 0) {
+ ohci->hc_control &= ~(OHCI_CTRL_PLE|OHCI_CTRL_IE);
+ ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
+ }
+}
+
+
+/*-------------------------------------------------------------------------*
+ * ED handling functions
+ *-------------------------------------------------------------------------*/
+
+/* search for the right schedule branch to use for a periodic ed.
+ * does some load balancing; returns the branch, or negative errno.
+ */
+static int balance (struct ohci_hcd *ohci, int interval, int load)
+{
+ int i, branch = -ENOSPC;
+
+ /* iso periods can be huge; iso tds specify frame numbers */
+ if (interval > NUM_INTS)
+ interval = NUM_INTS;
+
+ /* search for the least loaded schedule branch of that period
+ * that has enough bandwidth left unreserved.
+ */
+ for (i = 0; i < interval ; i++) {
+ if (branch < 0 || ohci->load [branch] > ohci->load [i]) {
+#if 1 /* CONFIG_USB_BANDWIDTH */
+ int j;
+
+ /* usb 1.1 says 90% of one frame */
+ for (j = i; j < NUM_INTS; j += interval) {
+ if ((ohci->load [j] + load) > 900)
+ break;
+ }
+ if (j < NUM_INTS)
+ continue;
+#endif
+ branch = i;
+ }
+ }
+ return branch;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* both iso and interrupt requests have periods; this routine puts them
+ * into the schedule tree in the apppropriate place. most iso devices use
+ * 1msec periods, but that's not required.
+ */
+static void periodic_link (struct ohci_hcd *ohci, struct ed *ed)
+{
+ unsigned i;
+
+ ohci_vdbg (ohci, "link %sed %p branch %d [%dus.], interval %d\n",
+ (ed->hwINFO & cpu_to_hc32 (ohci, ED_ISO)) ? "iso " : "",
+ ed, ed->branch, ed->load, ed->interval);
+
+ for (i = ed->branch; i < NUM_INTS; i += ed->interval) {
+ struct ed **prev = &ohci->periodic [i];
+ __hc32 *prev_p = &ohci->hcca->int_table [i];
+ struct ed *here = *prev;
+
+ /* sorting each branch by period (slow before fast)
+ * lets us share the faster parts of the tree.
+ * (plus maybe: put interrupt eds before iso)
+ */
+ while (here && ed != here) {
+ if (ed->interval > here->interval)
+ break;
+ prev = &here->ed_next;
+ prev_p = &here->hwNextED;
+ here = *prev;
+ }
+ if (ed != here) {
+ ed->ed_next = here;
+ if (here)
+ ed->hwNextED = *prev_p;
+ wmb ();
+ *prev = ed;
+ *prev_p = cpu_to_hc32(ohci, ed->dma);
+ wmb();
+ }
+ ohci->load [i] += ed->load;
+ }
+ ohci_to_hcd(ohci)->self.bandwidth_allocated += ed->load / ed->interval;
+}
+
+/* link an ed into one of the HC chains */
+
+static int ed_schedule (struct ohci_hcd *ohci, struct ed *ed)
+{
+ int branch;
+
+ if (ohci_to_hcd(ohci)->state == HC_STATE_QUIESCING)
+ return -EAGAIN;
+
+ ed->state = ED_OPER;
+ ed->ed_prev = NULL;
+ ed->ed_next = NULL;
+ ed->hwNextED = 0;
+ wmb ();
+
+ /* we care about rm_list when setting CLE/BLE in case the HC was at
+ * work on some TD when CLE/BLE was turned off, and isn't quiesced
+ * yet. finish_unlinks() restarts as needed, some upcoming INTR_SF.
+ *
+ * control and bulk EDs are doubly linked (ed_next, ed_prev), but
+ * periodic ones are singly linked (ed_next). that's because the
+ * periodic schedule encodes a tree like figure 3-5 in the ohci
+ * spec: each qh can have several "previous" nodes, and the tree
+ * doesn't have unused/idle descriptors.
+ */
+ switch (ed->type) {
+ case PIPE_CONTROL:
+ if (ohci->ed_controltail == NULL) {
+ WARN_ON (ohci->hc_control & OHCI_CTRL_CLE);
+ ohci_writel (ohci, ed->dma,
+ &ohci->regs->ed_controlhead);
+ } else {
+ ohci->ed_controltail->ed_next = ed;
+ ohci->ed_controltail->hwNextED = cpu_to_hc32 (ohci,
+ ed->dma);
+ }
+ ed->ed_prev = ohci->ed_controltail;
+ if (!ohci->ed_controltail && !ohci->ed_rm_list) {
+ wmb();
+ ohci->hc_control |= OHCI_CTRL_CLE;
+ ohci_writel (ohci, 0, &ohci->regs->ed_controlcurrent);
+ ohci_writel (ohci, ohci->hc_control,
+ &ohci->regs->control);
+ }
+ ohci->ed_controltail = ed;
+ break;
+
+ case PIPE_BULK:
+ if (ohci->ed_bulktail == NULL) {
+ WARN_ON (ohci->hc_control & OHCI_CTRL_BLE);
+ ohci_writel (ohci, ed->dma, &ohci->regs->ed_bulkhead);
+ } else {
+ ohci->ed_bulktail->ed_next = ed;
+ ohci->ed_bulktail->hwNextED = cpu_to_hc32 (ohci,
+ ed->dma);
+ }
+ ed->ed_prev = ohci->ed_bulktail;
+ if (!ohci->ed_bulktail && !ohci->ed_rm_list) {
+ wmb();
+ ohci->hc_control |= OHCI_CTRL_BLE;
+ ohci_writel (ohci, 0, &ohci->regs->ed_bulkcurrent);
+ ohci_writel (ohci, ohci->hc_control,
+ &ohci->regs->control);
+ }
+ ohci->ed_bulktail = ed;
+ break;
+
+ // case PIPE_INTERRUPT:
+ // case PIPE_ISOCHRONOUS:
+ default:
+ branch = balance (ohci, ed->interval, ed->load);
+ if (branch < 0) {
+ ohci_dbg (ohci,
+ "ERR %d, interval %d msecs, load %d\n",
+ branch, ed->interval, ed->load);
+ // FIXME if there are TDs queued, fail them!
+ return branch;
+ }
+ ed->branch = branch;
+ periodic_link (ohci, ed);
+ }
+
+ /* the HC may not see the schedule updates yet, but if it does
+ * then they'll be properly ordered.
+ */
+ return 0;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* scan the periodic table to find and unlink this ED */
+static void periodic_unlink (struct ohci_hcd *ohci, struct ed *ed)
+{
+ int i;
+
+ for (i = ed->branch; i < NUM_INTS; i += ed->interval) {
+ struct ed *temp;
+ struct ed **prev = &ohci->periodic [i];
+ __hc32 *prev_p = &ohci->hcca->int_table [i];
+
+ while (*prev && (temp = *prev) != ed) {
+ prev_p = &temp->hwNextED;
+ prev = &temp->ed_next;
+ }
+ if (*prev) {
+ *prev_p = ed->hwNextED;
+ *prev = ed->ed_next;
+ }
+ ohci->load [i] -= ed->load;
+ }
+ ohci_to_hcd(ohci)->self.bandwidth_allocated -= ed->load / ed->interval;
+
+ ohci_vdbg (ohci, "unlink %sed %p branch %d [%dus.], interval %d\n",
+ (ed->hwINFO & cpu_to_hc32 (ohci, ED_ISO)) ? "iso " : "",
+ ed, ed->branch, ed->load, ed->interval);
+}
+
+/* unlink an ed from one of the HC chains.
+ * just the link to the ed is unlinked.
+ * the link from the ed still points to another operational ed or 0
+ * so the HC can eventually finish the processing of the unlinked ed
+ * (assuming it already started that, which needn't be true).
+ *
+ * ED_UNLINK is a transient state: the HC may still see this ED, but soon
+ * it won't. ED_SKIP means the HC will finish its current transaction,
+ * but won't start anything new. The TD queue may still grow; device
+ * drivers don't know about this HCD-internal state.
+ *
+ * When the HC can't see the ED, something changes ED_UNLINK to one of:
+ *
+ * - ED_OPER: when there's any request queued, the ED gets rescheduled
+ * immediately. HC should be working on them.
+ *
+ * - ED_IDLE: when there's no TD queue. there's no reason for the HC
+ * to care about this ED; safe to disable the endpoint.
+ *
+ * When finish_unlinks() runs later, after SOF interrupt, it will often
+ * complete one or more URB unlinks before making that state change.
+ */
+static void ed_deschedule (struct ohci_hcd *ohci, struct ed *ed)
+{
+ ed->hwINFO |= cpu_to_hc32 (ohci, ED_SKIP);
+ wmb ();
+ ed->state = ED_UNLINK;
+
+ /* To deschedule something from the control or bulk list, just
+ * clear CLE/BLE and wait. There's no safe way to scrub out list
+ * head/current registers until later, and "later" isn't very
+ * tightly specified. Figure 6-5 and Section 6.4.2.2 show how
+ * the HC is reading the ED queues (while we modify them).
+ *
+ * For now, ed_schedule() is "later". It might be good paranoia
+ * to scrub those registers in finish_unlinks(), in case of bugs
+ * that make the HC try to use them.
+ */
+ switch (ed->type) {
+ case PIPE_CONTROL:
+ /* remove ED from the HC's list: */
+ if (ed->ed_prev == NULL) {
+ if (!ed->hwNextED) {
+ ohci->hc_control &= ~OHCI_CTRL_CLE;
+ ohci_writel (ohci, ohci->hc_control,
+ &ohci->regs->control);
+ // a ohci_readl() later syncs CLE with the HC
+ } else
+ ohci_writel (ohci,
+ hc32_to_cpup (ohci, &ed->hwNextED),
+ &ohci->regs->ed_controlhead);
+ } else {
+ ed->ed_prev->ed_next = ed->ed_next;
+ ed->ed_prev->hwNextED = ed->hwNextED;
+ }
+ /* remove ED from the HCD's list: */
+ if (ohci->ed_controltail == ed) {
+ ohci->ed_controltail = ed->ed_prev;
+ if (ohci->ed_controltail)
+ ohci->ed_controltail->ed_next = NULL;
+ } else if (ed->ed_next) {
+ ed->ed_next->ed_prev = ed->ed_prev;
+ }
+ break;
+
+ case PIPE_BULK:
+ /* remove ED from the HC's list: */
+ if (ed->ed_prev == NULL) {
+ if (!ed->hwNextED) {
+ ohci->hc_control &= ~OHCI_CTRL_BLE;
+ ohci_writel (ohci, ohci->hc_control,
+ &ohci->regs->control);
+ // a ohci_readl() later syncs BLE with the HC
+ } else
+ ohci_writel (ohci,
+ hc32_to_cpup (ohci, &ed->hwNextED),
+ &ohci->regs->ed_bulkhead);
+ } else {
+ ed->ed_prev->ed_next = ed->ed_next;
+ ed->ed_prev->hwNextED = ed->hwNextED;
+ }
+ /* remove ED from the HCD's list: */
+ if (ohci->ed_bulktail == ed) {
+ ohci->ed_bulktail = ed->ed_prev;
+ if (ohci->ed_bulktail)
+ ohci->ed_bulktail->ed_next = NULL;
+ } else if (ed->ed_next) {
+ ed->ed_next->ed_prev = ed->ed_prev;
+ }
+ break;
+
+ // case PIPE_INTERRUPT:
+ // case PIPE_ISOCHRONOUS:
+ default:
+ periodic_unlink (ohci, ed);
+ break;
+ }
+}
+
+
+/*-------------------------------------------------------------------------*/
+
+/* get and maybe (re)init an endpoint. init _should_ be done only as part
+ * of enumeration, usb_set_configuration() or usb_set_interface().
+ */
+static struct ed *ed_get (
+ struct ohci_hcd *ohci,
+ struct usb_host_endpoint *ep,
+ struct usb_device *udev,
+ unsigned int pipe,
+ int interval
+) {
+ struct ed *ed;
+ unsigned long flags;
+
+ spin_lock_irqsave (&ohci->lock, flags);
+
+ if (!(ed = ep->hcpriv)) {
+ struct td *td;
+ int is_out;
+ u32 info;
+
+ ed = ed_alloc (ohci, GFP_ATOMIC);
+ if (!ed) {
+ /* out of memory */
+ goto done;
+ }
+
+ /* dummy td; end of td list for ed */
+ td = td_alloc (ohci, GFP_ATOMIC);
+ if (!td) {
+ /* out of memory */
+ ed_free (ohci, ed);
+ ed = NULL;
+ goto done;
+ }
+ ed->dummy = td;
+ ed->hwTailP = cpu_to_hc32 (ohci, td->td_dma);
+ ed->hwHeadP = ed->hwTailP; /* ED_C, ED_H zeroed */
+ ed->state = ED_IDLE;
+
+ is_out = !(ep->desc.bEndpointAddress & USB_DIR_IN);
+
+ /* FIXME usbcore changes dev->devnum before SET_ADDRESS
+ * suceeds ... otherwise we wouldn't need "pipe".
+ */
+ info = usb_pipedevice (pipe);
+ ed->type = usb_pipetype(pipe);
+
+ info |= (ep->desc.bEndpointAddress & ~USB_DIR_IN) << 7;
+ info |= le16_to_cpu(ep->desc.wMaxPacketSize) << 16;
+ if (udev->speed == USB_SPEED_LOW)
+ info |= ED_LOWSPEED;
+ /* only control transfers store pids in tds */
+ if (ed->type != PIPE_CONTROL) {
+ info |= is_out ? ED_OUT : ED_IN;
+ if (ed->type != PIPE_BULK) {
+ /* periodic transfers... */
+ if (ed->type == PIPE_ISOCHRONOUS)
+ info |= ED_ISO;
+ else if (interval > 32) /* iso can be bigger */
+ interval = 32;
+ ed->interval = interval;
+ ed->load = usb_calc_bus_time (
+ udev->speed, !is_out,
+ ed->type == PIPE_ISOCHRONOUS,
+ le16_to_cpu(ep->desc.wMaxPacketSize))
+ / 1000;
+ }
+ }
+ ed->hwINFO = cpu_to_hc32(ohci, info);
+
+ ep->hcpriv = ed;
+ }
+
+done:
+ spin_unlock_irqrestore (&ohci->lock, flags);
+ return ed;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* request unlinking of an endpoint from an operational HC.
+ * put the ep on the rm_list
+ * real work is done at the next start frame (SF) hardware interrupt
+ * caller guarantees HCD is running, so hardware access is safe,
+ * and that ed->state is ED_OPER
+ */
+static void start_ed_unlink (struct ohci_hcd *ohci, struct ed *ed)
+{
+ ed->hwINFO |= cpu_to_hc32 (ohci, ED_DEQUEUE);
+ ed_deschedule (ohci, ed);
+
+ /* rm_list is just singly linked, for simplicity */
+ ed->ed_next = ohci->ed_rm_list;
+ ed->ed_prev = NULL;
+ ohci->ed_rm_list = ed;
+
+ /* enable SOF interrupt */
+ ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrstatus);
+ ohci_writel (ohci, OHCI_INTR_SF, &ohci->regs->intrenable);
+ // flush those writes, and get latest HCCA contents
+ (void) ohci_readl (ohci, &ohci->regs->control);
+
+ /* SF interrupt might get delayed; record the frame counter value that
+ * indicates when the HC isn't looking at it, so concurrent unlinks
+ * behave. frame_no wraps every 2^16 msec, and changes right before
+ * SF is triggered.
+ */
+ ed->tick = ohci_frame_no(ohci) + 1;
+
+}
+
+/*-------------------------------------------------------------------------*
+ * TD handling functions
+ *-------------------------------------------------------------------------*/
+
+/* enqueue next TD for this URB (OHCI spec 5.2.8.2) */
+
+static void
+td_fill (struct ohci_hcd *ohci, u32 info,
+ dma_addr_t data, int len,
+ struct urb *urb, int index)
+{
+ struct td *td, *td_pt;
+ struct urb_priv *urb_priv = urb->hcpriv;
+ int is_iso = info & TD_ISO;
+ int hash;
+
+ // ASSERT (index < urb_priv->length);
+
+ /* aim for only one interrupt per urb. mostly applies to control
+ * and iso; other urbs rarely need more than one TD per urb.
+ * this way, only final tds (or ones with an error) cause IRQs.
+ * at least immediately; use DI=6 in case any control request is
+ * tempted to die part way through. (and to force the hc to flush
+ * its donelist soonish, even on unlink paths.)
+ *
+ * NOTE: could delay interrupts even for the last TD, and get fewer
+ * interrupts ... increasing per-urb latency by sharing interrupts.
+ * Drivers that queue bulk urbs may request that behavior.
+ */
+ if (index != (urb_priv->length - 1)
+ || (urb->transfer_flags & URB_NO_INTERRUPT))
+ info |= TD_DI_SET (6);
+
+ /* use this td as the next dummy */
+ td_pt = urb_priv->td [index];
+
+ /* fill the old dummy TD */
+ td = urb_priv->td [index] = urb_priv->ed->dummy;
+ urb_priv->ed->dummy = td_pt;
+
+ td->ed = urb_priv->ed;
+ td->next_dl_td = NULL;
+ td->index = index;
+ td->urb = urb;
+ td->data_dma = data;
+ if (!len)
+ data = 0;
+
+ td->hwINFO = cpu_to_hc32 (ohci, info);
+ if (is_iso) {
+ td->hwCBP = cpu_to_hc32 (ohci, data & 0xFFFFF000);
+ *ohci_hwPSWp(ohci, td, 0) = cpu_to_hc16 (ohci,
+ (data & 0x0FFF) | 0xE000);
+ td->ed->last_iso = info & 0xffff;
+ } else {
+ td->hwCBP = cpu_to_hc32 (ohci, data);
+ }
+ if (data)
+ td->hwBE = cpu_to_hc32 (ohci, data + len - 1);
+ else
+ td->hwBE = 0;
+ td->hwNextTD = cpu_to_hc32 (ohci, td_pt->td_dma);
+
+ /* append to queue */
+ list_add_tail (&td->td_list, &td->ed->td_list);
+
+ /* hash it for later reverse mapping */
+ hash = TD_HASH_FUNC (td->td_dma);
+ td->td_hash = ohci->td_hash [hash];
+ ohci->td_hash [hash] = td;
+
+ /* HC might read the TD (or cachelines) right away ... */
+ wmb ();
+ td->ed->hwTailP = td->hwNextTD;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* Prepare all TDs of a transfer, and queue them onto the ED.
+ * Caller guarantees HC is active.
+ * Usually the ED is already on the schedule, so TDs might be
+ * processed as soon as they're queued.
+ */
+static void td_submit_urb (
+ struct ohci_hcd *ohci,
+ struct urb *urb
+) {
+ struct urb_priv *urb_priv = urb->hcpriv;
+ dma_addr_t data;
+ int data_len = urb->transfer_buffer_length;
+ int cnt = 0;
+ u32 info = 0;
+ int is_out = usb_pipeout (urb->pipe);
+ int periodic = 0;
+
+ /* OHCI handles the bulk/interrupt data toggles itself. We just
+ * use the device toggle bits for resetting, and rely on the fact
+ * that resetting toggle is meaningless if the endpoint is active.
+ */
+ if (!usb_gettoggle (urb->dev, usb_pipeendpoint (urb->pipe), is_out)) {
+ usb_settoggle (urb->dev, usb_pipeendpoint (urb->pipe),
+ is_out, 1);
+ urb_priv->ed->hwHeadP &= ~cpu_to_hc32 (ohci, ED_C);
+ }
+
+ urb_priv->td_cnt = 0;
+ list_add (&urb_priv->pending, &ohci->pending);
+
+ if (data_len)
+ data = urb->transfer_dma;
+ else
+ data = 0;
+
+ /* NOTE: TD_CC is set so we can tell which TDs the HC processed by
+ * using TD_CC_GET, as well as by seeing them on the done list.
+ * (CC = NotAccessed ... 0x0F, or 0x0E in PSWs for ISO.)
+ */
+ switch (urb_priv->ed->type) {
+
+ /* Bulk and interrupt are identical except for where in the schedule
+ * their EDs live.
+ */
+ case PIPE_INTERRUPT:
+ /* ... and periodic urbs have extra accounting */
+ periodic = ohci_to_hcd(ohci)->self.bandwidth_int_reqs++ == 0
+ && ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs == 0;
+ /* FALLTHROUGH */
+ case PIPE_BULK:
+ info = is_out
+ ? TD_T_TOGGLE | TD_CC | TD_DP_OUT
+ : TD_T_TOGGLE | TD_CC | TD_DP_IN;
+ /* TDs _could_ transfer up to 8K each */
+ while (data_len > 4096) {
+ td_fill (ohci, info, data, 4096, urb, cnt);
+ data += 4096;
+ data_len -= 4096;
+ cnt++;
+ }
+ /* maybe avoid ED halt on final TD short read */
+ if (!(urb->transfer_flags & URB_SHORT_NOT_OK))
+ info |= TD_R;
+ td_fill (ohci, info, data, data_len, urb, cnt);
+ cnt++;
+ if ((urb->transfer_flags & URB_ZERO_PACKET)
+ && cnt < urb_priv->length) {
+ td_fill (ohci, info, 0, 0, urb, cnt);
+ cnt++;
+ }
+ /* maybe kickstart bulk list */
+ if (urb_priv->ed->type == PIPE_BULK) {
+ wmb ();
+ ohci_writel (ohci, OHCI_BLF, &ohci->regs->cmdstatus);
+ }
+ break;
+
+ /* control manages DATA0/DATA1 toggle per-request; SETUP resets it,
+ * any DATA phase works normally, and the STATUS ack is special.
+ */
+ case PIPE_CONTROL:
+ info = TD_CC | TD_DP_SETUP | TD_T_DATA0;
+ td_fill (ohci, info, urb->setup_dma, 8, urb, cnt++);
+ if (data_len > 0) {
+ info = TD_CC | TD_R | TD_T_DATA1;
+ info |= is_out ? TD_DP_OUT : TD_DP_IN;
+ /* NOTE: mishandles transfers >8K, some >4K */
+ td_fill (ohci, info, data, data_len, urb, cnt++);
+ }
+ info = (is_out || data_len == 0)
+ ? TD_CC | TD_DP_IN | TD_T_DATA1
+ : TD_CC | TD_DP_OUT | TD_T_DATA1;
+ td_fill (ohci, info, data, 0, urb, cnt++);
+ /* maybe kickstart control list */
+ wmb ();
+ ohci_writel (ohci, OHCI_CLF, &ohci->regs->cmdstatus);
+ break;
+
+ /* ISO has no retransmit, so no toggle; and it uses special TDs.
+ * Each TD could handle multiple consecutive frames (interval 1);
+ * we could often reduce the number of TDs here.
+ */
+ case PIPE_ISOCHRONOUS:
+ for (cnt = 0; cnt < urb->number_of_packets; cnt++) {
+ int frame = urb->start_frame;
+
+ // FIXME scheduling should handle frame counter
+ // roll-around ... exotic case (and OHCI has
+ // a 2^16 iso range, vs other HCs max of 2^10)
+ frame += cnt * urb->interval;
+ frame &= 0xffff;
+ td_fill (ohci, TD_CC | TD_ISO | frame,
+ data + urb->iso_frame_desc [cnt].offset,
+ urb->iso_frame_desc [cnt].length, urb, cnt);
+ }
+ periodic = ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs++ == 0
+ && ohci_to_hcd(ohci)->self.bandwidth_int_reqs == 0;
+ break;
+ }
+
+ /* start periodic dma if needed */
+ if (periodic) {
+ wmb ();
+ ohci->hc_control |= OHCI_CTRL_PLE|OHCI_CTRL_IE;
+ ohci_writel (ohci, ohci->hc_control, &ohci->regs->control);
+ }
+
+ // ASSERT (urb_priv->length == cnt);
+}
+
+/*-------------------------------------------------------------------------*
+ * Done List handling functions
+ *-------------------------------------------------------------------------*/
+
+/* calculate transfer length/status and update the urb
+ * PRECONDITION: irqsafe (only for urb->status locking)
+ */
+static void td_done (struct ohci_hcd *ohci, struct urb *urb, struct td *td)
+{
+ u32 tdINFO = hc32_to_cpup (ohci, &td->hwINFO);
+ int cc = 0;
+
+ list_del (&td->td_list);
+
+ /* ISO ... drivers see per-TD length/status */
+ if (tdINFO & TD_ISO) {
+ u16 tdPSW = ohci_hwPSW (ohci, td, 0);
+ int dlen = 0;
+
+ /* NOTE: assumes FC in tdINFO == 0, and that
+ * only the first of 0..MAXPSW psws is used.
+ */
+
+ cc = (tdPSW >> 12) & 0xF;
+ if (tdINFO & TD_CC) /* hc didn't touch? */
+ return;
+
+ if (usb_pipeout (urb->pipe))
+ dlen = urb->iso_frame_desc [td->index].length;
+ else {
+ /* short reads are always OK for ISO */
+ if (cc == TD_DATAUNDERRUN)
+ cc = TD_CC_NOERROR;
+ dlen = tdPSW & 0x3ff;
+ }
+ urb->actual_length += dlen;
+ urb->iso_frame_desc [td->index].actual_length = dlen;
+ urb->iso_frame_desc [td->index].status = cc_to_error [cc];
+
+ if (cc != TD_CC_NOERROR)
+ ohci_vdbg (ohci,
+ "urb %p iso td %p (%d) len %d cc %d\n",
+ urb, td, 1 + td->index, dlen, cc);
+
+ /* BULK, INT, CONTROL ... drivers see aggregate length/status,
+ * except that "setup" bytes aren't counted and "short" transfers
+ * might not be reported as errors.
+ */
+ } else {
+ int type = usb_pipetype (urb->pipe);
+ u32 tdBE = hc32_to_cpup (ohci, &td->hwBE);
+
+ cc = TD_CC_GET (tdINFO);
+
+ /* update packet status if needed (short is normally ok) */
+ if (cc == TD_DATAUNDERRUN
+ && !(urb->transfer_flags & URB_SHORT_NOT_OK))
+ cc = TD_CC_NOERROR;
+ if (cc != TD_CC_NOERROR && cc < 0x0E) {
+ spin_lock (&urb->lock);
+ if (urb->status == -EINPROGRESS)
+ urb->status = cc_to_error [cc];
+ spin_unlock (&urb->lock);
+ }
+
+ /* count all non-empty packets except control SETUP packet */
+ if ((type != PIPE_CONTROL || td->index != 0) && tdBE != 0) {
+ if (td->hwCBP == 0)
+ urb->actual_length += tdBE - td->data_dma + 1;
+ else
+ urb->actual_length +=
+ hc32_to_cpup (ohci, &td->hwCBP)
+ - td->data_dma;
+ }
+
+ if (cc != TD_CC_NOERROR && cc < 0x0E)
+ ohci_vdbg (ohci,
+ "urb %p td %p (%d) cc %d, len=%d/%d\n",
+ urb, td, 1 + td->index, cc,
+ urb->actual_length,
+ urb->transfer_buffer_length);
+ }
+}
+
+/*-------------------------------------------------------------------------*/
+
+static inline struct td *
+ed_halted (struct ohci_hcd *ohci, struct td *td, int cc, struct td *rev)
+{
+ struct urb *urb = td->urb;
+ struct ed *ed = td->ed;
+ struct list_head *tmp = td->td_list.next;
+ __hc32 toggle = ed->hwHeadP & cpu_to_hc32 (ohci, ED_C);
+
+ /* clear ed halt; this is the td that caused it, but keep it inactive
+ * until its urb->complete() has a chance to clean up.
+ */
+ ed->hwINFO |= cpu_to_hc32 (ohci, ED_SKIP);
+ wmb ();
+ ed->hwHeadP &= ~cpu_to_hc32 (ohci, ED_H);
+
+ /* put any later tds from this urb onto the donelist, after 'td',
+ * order won't matter here: no errors, and nothing was transferred.
+ * also patch the ed so it looks as if those tds completed normally.
+ */
+ while (tmp != &ed->td_list) {
+ struct td *next;
+ __hc32 info;
+
+ next = list_entry (tmp, struct td, td_list);
+ tmp = next->td_list.next;
+
+ if (next->urb != urb)
+ break;
+
+ /* NOTE: if multi-td control DATA segments get supported,
+ * this urb had one of them, this td wasn't the last td
+ * in that segment (TD_R clear), this ed halted because
+ * of a short read, _and_ URB_SHORT_NOT_OK is clear ...
+ * then we need to leave the control STATUS packet queued
+ * and clear ED_SKIP.
+ */
+ info = next->hwINFO;
+ info |= cpu_to_hc32 (ohci, TD_DONE);
+ info &= ~cpu_to_hc32 (ohci, TD_CC);
+ next->hwINFO = info;
+
+ next->next_dl_td = rev;
+ rev = next;
+
+ ed->hwHeadP = next->hwNextTD | toggle;
+ }
+
+ /* help for troubleshooting: report anything that
+ * looks odd ... that doesn't include protocol stalls
+ * (or maybe some other things)
+ */
+ switch (cc) {
+ case TD_DATAUNDERRUN:
+ if ((urb->transfer_flags & URB_SHORT_NOT_OK) == 0)
+ break;
+ /* fallthrough */
+ case TD_CC_STALL:
+ if (usb_pipecontrol (urb->pipe))
+ break;
+ /* fallthrough */
+ default:
+ ohci_dbg (ohci,
+ "urb %p path %s ep%d%s %08x cc %d --> status %d\n",
+ urb, urb->dev->devpath,
+ usb_pipeendpoint (urb->pipe),
+ usb_pipein (urb->pipe) ? "in" : "out",
+ hc32_to_cpu (ohci, td->hwINFO),
+ cc, cc_to_error [cc]);
+ }
+
+ return rev;
+}
+
+/* replies to the request have to be on a FIFO basis so
+ * we unreverse the hc-reversed done-list
+ */
+static struct td *dl_reverse_done_list (struct ohci_hcd *ohci)
+{
+ u32 td_dma;
+ struct td *td_rev = NULL;
+ struct td *td = NULL;
+
+ td_dma = hc32_to_cpup (ohci, &ohci->hcca->done_head);
+ ohci->hcca->done_head = 0;
+ wmb();
+
+ /* get TD from hc's singly linked list, and
+ * prepend to ours. ed->td_list changes later.
+ */
+ while (td_dma) {
+ int cc;
+
+ td = dma_to_td (ohci, td_dma);
+ if (!td) {
+ ohci_err (ohci, "bad entry %8x\n", td_dma);
+ break;
+ }
+
+ td->hwINFO |= cpu_to_hc32 (ohci, TD_DONE);
+ cc = TD_CC_GET (hc32_to_cpup (ohci, &td->hwINFO));
+
+ /* Non-iso endpoints can halt on error; un-halt,
+ * and dequeue any other TDs from this urb.
+ * No other TD could have caused the halt.
+ */
+ if (cc != TD_CC_NOERROR
+ && (td->ed->hwHeadP & cpu_to_hc32 (ohci, ED_H)))
+ td_rev = ed_halted (ohci, td, cc, td_rev);
+
+ td->next_dl_td = td_rev;
+ td_rev = td;
+ td_dma = hc32_to_cpup (ohci, &td->hwNextTD);
+ }
+ return td_rev;
+}
+
+/*-------------------------------------------------------------------------*/
+
+/* there are some urbs/eds to unlink; called in_irq(), with HCD locked */
+static void
+finish_unlinks (struct ohci_hcd *ohci, u16 tick, struct pt_regs *regs)
+{
+ struct ed *ed, **last;
+
+rescan_all:
+ for (last = &ohci->ed_rm_list, ed = *last; ed != NULL; ed = *last) {
+ struct list_head *entry, *tmp;
+ int completed, modified;
+ __hc32 *prev;
+
+ /* only take off EDs that the HC isn't using, accounting for
+ * frame counter wraps and EDs with partially retired TDs
+ */
+ if (likely (regs && HC_IS_RUNNING(ohci_to_hcd(ohci)->state))) {
+ if (tick_before (tick, ed->tick)) {
+skip_ed:
+ last = &ed->ed_next;
+ continue;
+ }
+
+ if (!list_empty (&ed->td_list)) {
+ struct td *td;
+ u32 head;
+
+ td = list_entry (ed->td_list.next, struct td,
+ td_list);
+ head = hc32_to_cpu (ohci, ed->hwHeadP) &
+ TD_MASK;
+
+ /* INTR_WDH may need to clean up first */
+ if (td->td_dma != head)
+ goto skip_ed;
+ }
+ }
+
+ /* reentrancy: if we drop the schedule lock, someone might
+ * have modified this list. normally it's just prepending
+ * entries (which we'd ignore), but paranoia won't hurt.
+ */
+ *last = ed->ed_next;
+ ed->ed_next = NULL;
+ modified = 0;
+
+ /* unlink urbs as requested, but rescan the list after
+ * we call a completion since it might have unlinked
+ * another (earlier) urb
+ *
+ * When we get here, the HC doesn't see this ed. But it
+ * must not be rescheduled until all completed URBs have
+ * been given back to the driver.
+ */
+rescan_this:
+ completed = 0;
+ prev = &ed->hwHeadP;
+ list_for_each_safe (entry, tmp, &ed->td_list) {
+ struct td *td;
+ struct urb *urb;
+ urb_priv_t *urb_priv;
+ __hc32 savebits;
+
+ td = list_entry (entry, struct td, td_list);
+ urb = td->urb;
+ urb_priv = td->urb->hcpriv;
+
+ if (urb->status == -EINPROGRESS) {
+ prev = &td->hwNextTD;
+ continue;
+ }
+
+ /* patch pointer hc uses */
+ savebits = *prev & ~cpu_to_hc32 (ohci, TD_MASK);
+ *prev = td->hwNextTD | savebits;
+
+ /* HC may have partly processed this TD */
+ td_done (ohci, urb, td);
+ urb_priv->td_cnt++;
+
+ /* if URB is done, clean up */
+ if (urb_priv->td_cnt == urb_priv->length) {
+ modified = completed = 1;
+ finish_urb (ohci, urb, regs);
+ }
+ }
+ if (completed && !list_empty (&ed->td_list))
+ goto rescan_this;
+
+ /* ED's now officially unlinked, hc doesn't see */
+ ed->state = ED_IDLE;
+ ed->hwHeadP &= ~cpu_to_hc32(ohci, ED_H);
+ ed->hwNextED = 0;
+ wmb ();
+ ed->hwINFO &= ~cpu_to_hc32 (ohci, ED_SKIP | ED_DEQUEUE);
+
+ /* but if there's work queued, reschedule */
+ if (!list_empty (&ed->td_list)) {
+ if (HC_IS_RUNNING(ohci_to_hcd(ohci)->state))
+ ed_schedule (ohci, ed);
+ }
+
+ if (modified)
+ goto rescan_all;
+ }
+
+ /* maybe reenable control and bulk lists */
+ if (HC_IS_RUNNING(ohci_to_hcd(ohci)->state)
+ && ohci_to_hcd(ohci)->state != HC_STATE_QUIESCING
+ && !ohci->ed_rm_list) {
+ u32 command = 0, control = 0;
+
+ if (ohci->ed_controltail) {
+ command |= OHCI_CLF;
+ if (!(ohci->hc_control & OHCI_CTRL_CLE)) {
+ control |= OHCI_CTRL_CLE;
+ ohci_writel (ohci, 0,
+ &ohci->regs->ed_controlcurrent);
+ }
+ }
+ if (ohci->ed_bulktail) {
+ command |= OHCI_BLF;
+ if (!(ohci->hc_control & OHCI_CTRL_BLE)) {
+ control |= OHCI_CTRL_BLE;
+ ohci_writel (ohci, 0,
+ &ohci->regs->ed_bulkcurrent);
+ }
+ }
+
+ /* CLE/BLE to enable, CLF/BLF to (maybe) kickstart */
+ if (control) {
+ ohci->hc_control |= control;
+ ohci_writel (ohci, ohci->hc_control,
+ &ohci->regs->control);
+ }
+ if (command)
+ ohci_writel (ohci, command, &ohci->regs->cmdstatus);
+ }
+}
+
+
+
+/*-------------------------------------------------------------------------*/
+
+/*
+ * Process normal completions (error or success) and clean the schedules.
+ *
+ * This is the main path for handing urbs back to drivers. The only other
+ * path is finish_unlinks(), which unlinks URBs using ed_rm_list, instead of
+ * scanning the (re-reversed) donelist as this does.
+ */
+static void
+dl_done_list (struct ohci_hcd *ohci, struct pt_regs *regs)
+{
+ struct td *td = dl_reverse_done_list (ohci);
+
+ while (td) {
+ struct td *td_next = td->next_dl_td;
+ struct urb *urb = td->urb;
+ urb_priv_t *urb_priv = urb->hcpriv;
+ struct ed *ed = td->ed;
+
+ /* update URB's length and status from TD */
+ td_done (ohci, urb, td);
+ urb_priv->td_cnt++;
+
+ /* If all this urb's TDs are done, call complete() */
+ if (urb_priv->td_cnt == urb_priv->length)
+ finish_urb (ohci, urb, regs);
+
+ /* clean schedule: unlink EDs that are no longer busy */
+ if (list_empty (&ed->td_list)) {
+ if (ed->state == ED_OPER)
+ start_ed_unlink (ohci, ed);
+
+ /* ... reenabling halted EDs only after fault cleanup */
+ } else if ((ed->hwINFO & cpu_to_hc32 (ohci, ED_SKIP | ED_DEQUEUE))
+ == cpu_to_hc32 (ohci, ED_SKIP)) {
+ td = list_entry (ed->td_list.next, struct td, td_list);
+ if (!(td->hwINFO & cpu_to_hc32 (ohci, TD_DONE))) {
+ ed->hwINFO &= ~cpu_to_hc32 (ohci, ED_SKIP);
+ /* ... hc may need waking-up */
+ switch (ed->type) {
+ case PIPE_CONTROL:
+ ohci_writel (ohci, OHCI_CLF,
+ &ohci->regs->cmdstatus);
+ break;
+ case PIPE_BULK:
+ ohci_writel (ohci, OHCI_BLF,
+ &ohci->regs->cmdstatus);
+ break;
+ }
+ }
+ }
+
+ td = td_next;
+ }
+}