// SPDX-License-Identifier: GPL-1.0+ /* * OHCI HCD (Host Controller Driver) for USB. * * (C) Copyright 1999 Roman Weissgaerber * (C) Copyright 2000-2002 David Brownell * * This file is licenced under the GPL. */ #include #include 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, int status) __releases(ohci->lock) __acquires(ohci->lock) { struct device *dev = ohci_to_hcd(ohci)->self.controller; struct usb_host_endpoint *ep = urb->ep; struct urb_priv *urb_priv; // ASSERT (urb->hcpriv != 0); restart: urb_free_priv (ohci, urb->hcpriv); urb->hcpriv = NULL; if (likely(status == -EINPROGRESS)) status = 0; switch (usb_pipetype (urb->pipe)) { case PIPE_ISOCHRONOUS: ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs--; if (ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs == 0) { if (quirk_amdiso(ohci)) usb_amd_quirk_pll_enable(); if (quirk_amdprefetch(ohci)) sb800_prefetch(dev, 0); } break; case PIPE_INTERRUPT: ohci_to_hcd(ohci)->self.bandwidth_int_reqs--; break; } /* urb->complete() can reenter this HCD */ usb_hcd_unlink_urb_from_ep(ohci_to_hcd(ohci), urb); spin_unlock (&ohci->lock); usb_hcd_giveback_urb(ohci_to_hcd(ohci), urb, status); 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); } /* * An isochronous URB that is sumitted too late won't have any TDs * (marked by the fact that the td_cnt value is larger than the * actual number of TDs). If the next URB on this endpoint is like * that, give it back now. */ if (!list_empty(&ep->urb_list)) { urb = list_first_entry(&ep->urb_list, struct urb, urb_list); urb_priv = urb->hcpriv; if (urb_priv->td_cnt > urb_priv->length) { status = 0; goto restart; } } } /*-------------------------------------------------------------------------* * 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]) { 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; 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_dbg(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; 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. */ ed->state = ED_OPER; 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_dbg(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 or the HC isn't running. * * 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); ed = ep->hcpriv; if (!ed) { 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 * succeeds ... otherwise we wouldn't need "pipe". */ info = usb_pipedevice (pipe); ed->type = usb_pipetype(pipe); info |= (ep->desc.bEndpointAddress & ~USB_DIR_IN) << 7; info |= usb_endpoint_maxp(&ep->desc) << 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, usb_endpoint_maxp(&ep->desc)) / 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); } 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; struct device *dev = ohci_to_hcd(ohci)->self.controller; 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; int i, this_sg_len, n; struct scatterlist *sg; /* 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); } list_add (&urb_priv->pending, &ohci->pending); i = urb->num_mapped_sgs; if (data_len > 0 && i > 0) { sg = urb->sg; data = sg_dma_address(sg); /* * urb->transfer_buffer_length may be smaller than the * size of the scatterlist (or vice versa) */ this_sg_len = min_t(int, sg_dma_len(sg), data_len); } else { sg = NULL; if (data_len) data = urb->transfer_dma; else data = 0; this_sg_len = data_len; } /* 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 */ for (;;) { n = min(this_sg_len, 4096); /* maybe avoid ED halt on final TD short read */ if (n >= data_len || (i == 1 && n >= this_sg_len)) { if (!(urb->transfer_flags & URB_SHORT_NOT_OK)) info |= TD_R; } td_fill(ohci, info, data, n, urb, cnt); this_sg_len -= n; data_len -= n; data += n; cnt++; if (this_sg_len <= 0) { if (--i <= 0 || data_len <= 0) break; sg = sg_next(sg); data = sg_dma_address(sg); this_sg_len = min_t(int, sg_dma_len(sg), data_len); } } 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 = urb_priv->td_cnt; 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); } if (ohci_to_hcd(ohci)->self.bandwidth_isoc_reqs == 0) { if (quirk_amdiso(ohci)) usb_amd_quirk_pll_disable(); if (quirk_amdprefetch(ohci)) sb800_prefetch(dev, 1); } 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 */ static int td_done(struct ohci_hcd *ohci, struct urb *urb, struct td *td) { u32 tdINFO = hc32_to_cpup (ohci, &td->hwINFO); int cc = 0; int status = -EINPROGRESS; 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 status; 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_dbg(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) status = cc_to_error[cc]; /* 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_dbg(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); } return status; } /*-------------------------------------------------------------------------*/ static void ed_halted(struct ohci_hcd *ohci, struct td *td, int cc) { struct urb *urb = td->urb; urb_priv_t *urb_priv = urb->hcpriv; 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); /* Get rid of all later tds from this urb. We don't have * to be careful: 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; 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. */ list_del(&next->td_list); urb_priv->td_cnt++; 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]); } } /* Add a TD to the done list */ static void add_to_done_list(struct ohci_hcd *ohci, struct td *td) { struct td *td2, *td_prev; struct ed *ed; if (td->next_dl_td) return; /* Already on the list */ /* Add all the TDs going back until we reach one that's on the list */ ed = td->ed; td2 = td_prev = td; list_for_each_entry_continue_reverse(td2, &ed->td_list, td_list) { if (td2->next_dl_td) break; td2->next_dl_td = td_prev; td_prev = td2; } if (ohci->dl_end) ohci->dl_end->next_dl_td = td_prev; else ohci->dl_start = td_prev; /* * Make td->next_dl_td point to td itself, to mark the fact * that td is on the done list. */ ohci->dl_end = td->next_dl_td = td; /* Did we just add the latest pending TD? */ td2 = ed->pending_td; if (td2 && td2->next_dl_td) ed->pending_td = NULL; } /* Get the entries on the hardware done queue and put them on our list */ static void update_done_list(struct ohci_hcd *ohci) { u32 td_dma; 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 * add 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))) ed_halted(ohci, td, cc); td_dma = hc32_to_cpup (ohci, &td->hwNextTD); add_to_done_list(ohci, td); } } /*-------------------------------------------------------------------------*/ /* there are some urbs/eds to unlink; called in_irq(), with HCD locked */ static void finish_unlinks(struct ohci_hcd *ohci) { unsigned tick = ohci_frame_no(ohci); 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(ohci->rh_state == OHCI_RH_RUNNING) && 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_first_entry(&ed->td_list, struct td, td_list); /* INTR_WDH may need to clean up first */ head = hc32_to_cpu(ohci, ed->hwHeadP) & TD_MASK; if (td->td_dma != head && ohci->rh_state == OHCI_RH_RUNNING) goto skip_ed; /* Don't mess up anything already on the done list */ if (td->next_dl_td) goto skip_ed; } /* ED's now officially unlinked, hc doesn't see */ ed->hwHeadP &= ~cpu_to_hc32(ohci, ED_H); ed->hwNextED = 0; wmb(); ed->hwINFO &= ~cpu_to_hc32(ohci, ED_SKIP | ED_DEQUEUE); /* 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; u32 tdINFO; td = list_entry (entry, struct td, td_list); urb = td->urb; urb_priv = td->urb->hcpriv; if (!urb->unlinked) { prev = &td->hwNextTD; continue; } /* patch pointer hc uses */ savebits = *prev & ~cpu_to_hc32 (ohci, TD_MASK); *prev = td->hwNextTD | savebits; /* If this was unlinked, the TD may not have been * retired ... so manually save the data toggle. * The controller ignores the value we save for * control and ISO endpoints. */ tdINFO = hc32_to_cpup(ohci, &td->hwINFO); if ((tdINFO & TD_T) == TD_T_DATA0) ed->hwHeadP &= ~cpu_to_hc32(ohci, ED_C); else if ((tdINFO & TD_T) == TD_T_DATA1) ed->hwHeadP |= cpu_to_hc32(ohci, ED_C); /* 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, 0); } } if (completed && !list_empty (&ed->td_list)) goto rescan_this; /* * If no TDs are queued, ED is now idle. * Otherwise, if the HC is running, reschedule. * If the HC isn't running, add ED back to the * start of the list for later processing. */ if (list_empty(&ed->td_list)) { ed->state = ED_IDLE; list_del(&ed->in_use_list); } else if (ohci->rh_state == OHCI_RH_RUNNING) { ed_schedule(ohci, ed); } else { ed->ed_next = ohci->ed_rm_list; ohci->ed_rm_list = ed; /* Don't loop on the same ED */ if (last == &ohci->ed_rm_list) last = &ed->ed_next; } if (modified) goto rescan_all; } /* maybe reenable control and bulk lists */ if (ohci->rh_state == OHCI_RH_RUNNING && !ohci->ed_rm_list) { u32 command = 0, control = 0; if (ohci->ed_controltail) { command |= OHCI_CLF; if (quirk_zfmicro(ohci)) mdelay(1); 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 (quirk_zfmicro(ohci)) mdelay(1); 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; if (quirk_zfmicro(ohci)) mdelay(1); ohci_writel (ohci, ohci->hc_control, &ohci->regs->control); } if (command) { if (quirk_zfmicro(ohci)) mdelay(1); ohci_writel (ohci, command, &ohci->regs->cmdstatus); } } } /*-------------------------------------------------------------------------*/ /* Take back a TD from the host controller */ static void takeback_td(struct ohci_hcd *ohci, struct td *td) { struct urb *urb = td->urb; urb_priv_t *urb_priv = urb->hcpriv; struct ed *ed = td->ed; int status; /* update URB's length and status from TD */ status = 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, status); /* 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; } } } } /* * Process normal completions (error or success) and clean the schedules. * * This is the main path for handing urbs back to drivers. The only other * normal path is finish_unlinks(), which unlinks URBs using ed_rm_list, * instead of scanning the (re-reversed) donelist as this does. */ static void process_done_list(struct ohci_hcd *ohci) { struct td *td; while (ohci->dl_start) { td = ohci->dl_start; if (td == ohci->dl_end) ohci->dl_start = ohci->dl_end = NULL; else ohci->dl_start = td->next_dl_td; takeback_td(ohci, td); } } /* * TD takeback and URB giveback must be single-threaded. * This routine takes care of it all. */ static void ohci_work(struct ohci_hcd *ohci) { if (ohci->working) { ohci->restart_work = 1; return; } ohci->working = 1; restart: process_done_list(ohci); if (ohci->ed_rm_list) finish_unlinks(ohci); if (ohci->restart_work) { ohci->restart_work = 0; goto restart; } ohci->working = 0; }