1 files changed, 894 insertions, 0 deletions

diff --git a/drivers/usb/host/fhci-sched.c b/drivers/usb/host/fhci-sched.c
new file mode 100644
index 000000000..3d12cdd5f
--- /dev/null
+++ b/drivers/usb/host/fhci-sched.c
@@ -0,0 +1,894 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Freescale QUICC Engine USB Host Controller Driver
+ *
+ * Copyright (c) Freescale Semicondutor, Inc. 2006, 2011.
+ *               Shlomi Gridish <gridish@freescale.com>
+ *               Jerry Huang <Chang-Ming.Huang@freescale.com>
+ * Copyright (c) Logic Product Development, Inc. 2007
+ *               Peter Barada <peterb@logicpd.com>
+ * Copyright (c) MontaVista Software, Inc. 2008.
+ *               Anton Vorontsov <avorontsov@ru.mvista.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/spinlock.h>
+#include <linux/delay.h>
+#include <linux/errno.h>
+#include <linux/list.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/usb.h>
+#include <linux/usb/hcd.h>
+#include <soc/fsl/qe/qe.h>
+#include <asm/fsl_gtm.h>
+#include "fhci.h"
+
+static void recycle_frame(struct fhci_usb *usb, struct packet *pkt)
+{
+	pkt->data = NULL;
+	pkt->len = 0;
+	pkt->status = USB_TD_OK;
+	pkt->info = 0;
+	pkt->priv_data = NULL;
+
+	cq_put(&usb->ep0->empty_frame_Q, pkt);
+}
+
+/* confirm submitted packet */
+void fhci_transaction_confirm(struct fhci_usb *usb, struct packet *pkt)
+{
+	struct td *td;
+	struct packet *td_pkt;
+	struct ed *ed;
+	u32 trans_len;
+	bool td_done = false;
+
+	td = fhci_remove_td_from_frame(usb->actual_frame);
+	td_pkt = td->pkt;
+	trans_len = pkt->len;
+	td->status = pkt->status;
+	if (td->type == FHCI_TA_IN && td_pkt->info & PKT_DUMMY_PACKET) {
+		if ((td->data + td->actual_len) && trans_len)
+			memcpy(td->data + td->actual_len, pkt->data,
+			       trans_len);
+		cq_put(&usb->ep0->dummy_packets_Q, pkt->data);
+	}
+
+	recycle_frame(usb, pkt);
+
+	ed = td->ed;
+	if (ed->mode == FHCI_TF_ISO) {
+		if (ed->td_list.next->next != &ed->td_list) {
+			struct td *td_next =
+			    list_entry(ed->td_list.next->next, struct td,
+				       node);
+
+			td_next->start_frame = usb->actual_frame->frame_num;
+		}
+		td->actual_len = trans_len;
+		td_done = true;
+	} else if ((td->status & USB_TD_ERROR) &&
+			!(td->status & USB_TD_TX_ER_NAK)) {
+		/*
+		 * There was an error on the transaction (but not NAK).
+		 * If it is fatal error (data underrun, stall, bad pid or 3
+		 * errors exceeded), mark this TD as done.
+		 */
+		if ((td->status & USB_TD_RX_DATA_UNDERUN) ||
+				(td->status & USB_TD_TX_ER_STALL) ||
+				(td->status & USB_TD_RX_ER_PID) ||
+				(++td->error_cnt >= 3)) {
+			ed->state = FHCI_ED_HALTED;
+			td_done = true;
+
+			if (td->status & USB_TD_RX_DATA_UNDERUN) {
+				fhci_dbg(usb->fhci, "td err fu\n");
+				td->toggle = !td->toggle;
+				td->actual_len += trans_len;
+			} else {
+				fhci_dbg(usb->fhci, "td err f!u\n");
+			}
+		} else {
+			fhci_dbg(usb->fhci, "td err !f\n");
+			/* it is not a fatal error -retry this transaction */
+			td->nak_cnt = 0;
+			td->error_cnt++;
+			td->status = USB_TD_OK;
+		}
+	} else if (td->status & USB_TD_TX_ER_NAK) {
+		/* there was a NAK response */
+		fhci_vdbg(usb->fhci, "td nack\n");
+		td->nak_cnt++;
+		td->error_cnt = 0;
+		td->status = USB_TD_OK;
+	} else {
+		/* there was no error on transaction */
+		td->error_cnt = 0;
+		td->nak_cnt = 0;
+		td->toggle = !td->toggle;
+		td->actual_len += trans_len;
+
+		if (td->len == td->actual_len)
+			td_done = true;
+	}
+
+	if (td_done)
+		fhci_move_td_from_ed_to_done_list(usb, ed);
+}
+
+/*
+ * Flush all transmitted packets from BDs
+ * This routine is called when disabling the USB port to flush all
+ * transmissions that are already scheduled in the BDs
+ */
+void fhci_flush_all_transmissions(struct fhci_usb *usb)
+{
+	u8 mode;
+	struct td *td;
+
+	mode = in_8(&usb->fhci->regs->usb_usmod);
+	clrbits8(&usb->fhci->regs->usb_usmod, USB_MODE_EN);
+
+	fhci_flush_bds(usb);
+
+	while ((td = fhci_peek_td_from_frame(usb->actual_frame)) != NULL) {
+		struct packet *pkt = td->pkt;
+
+		pkt->status = USB_TD_TX_ER_TIMEOUT;
+		fhci_transaction_confirm(usb, pkt);
+	}
+
+	usb->actual_frame->frame_status = FRAME_END_TRANSMISSION;
+
+	/* reset the event register */
+	out_be16(&usb->fhci->regs->usb_usber, 0xffff);
+	/* enable the USB controller */
+	out_8(&usb->fhci->regs->usb_usmod, mode | USB_MODE_EN);
+}
+
+/*
+ * This function forms the packet and transmit the packet. This function
+ * will handle all endpoint type:ISO,interrupt,control and bulk
+ */
+static int add_packet(struct fhci_usb *usb, struct ed *ed, struct td *td)
+{
+	u32 fw_transaction_time, len = 0;
+	struct packet *pkt;
+	u8 *data = NULL;
+
+	/* calcalate data address,len and toggle and then add the transaction */
+	if (td->toggle == USB_TD_TOGGLE_CARRY)
+		td->toggle = ed->toggle_carry;
+
+	switch (ed->mode) {
+	case FHCI_TF_ISO:
+		len = td->len;
+		if (td->type != FHCI_TA_IN)
+			data = td->data;
+		break;
+	case FHCI_TF_CTRL:
+	case FHCI_TF_BULK:
+		len = min(td->len - td->actual_len, ed->max_pkt_size);
+		if (!((td->type == FHCI_TA_IN) &&
+		      ((len + td->actual_len) == td->len)))
+			data = td->data + td->actual_len;
+		break;
+	case FHCI_TF_INTR:
+		len = min(td->len, ed->max_pkt_size);
+		if (!((td->type == FHCI_TA_IN) &&
+		      ((td->len + CRC_SIZE) >= ed->max_pkt_size)))
+			data = td->data;
+		break;
+	default:
+		break;
+	}
+
+	if (usb->port_status == FHCI_PORT_FULL)
+		fw_transaction_time = (((len + PROTOCOL_OVERHEAD) * 11) >> 4);
+	else
+		fw_transaction_time = ((len + PROTOCOL_OVERHEAD) * 6);
+
+	/* check if there's enough space in this frame to submit this TD */
+	if (usb->actual_frame->total_bytes + len + PROTOCOL_OVERHEAD >=
+			usb->max_bytes_per_frame) {
+		fhci_vdbg(usb->fhci, "not enough space in this frame: "
+			  "%d %d %d\n", usb->actual_frame->total_bytes, len,
+			  usb->max_bytes_per_frame);
+		return -1;
+	}
+
+	/* check if there's enough time in this frame to submit this TD */
+	if (usb->actual_frame->frame_status != FRAME_IS_PREPARED &&
+	    (usb->actual_frame->frame_status & FRAME_END_TRANSMISSION ||
+	     (fw_transaction_time + usb->sw_transaction_time >=
+	      1000 - fhci_get_sof_timer_count(usb)))) {
+		fhci_dbg(usb->fhci, "not enough time in this frame\n");
+		return -1;
+	}
+
+	/* update frame object fields before transmitting */
+	pkt = cq_get(&usb->ep0->empty_frame_Q);
+	if (!pkt) {
+		fhci_dbg(usb->fhci, "there is no empty frame\n");
+		return -1;
+	}
+	td->pkt = pkt;
+
+	pkt->info = 0;
+	if (data == NULL) {
+		data = cq_get(&usb->ep0->dummy_packets_Q);
+		BUG_ON(!data);
+		pkt->info = PKT_DUMMY_PACKET;
+	}
+	pkt->data = data;
+	pkt->len = len;
+	pkt->status = USB_TD_OK;
+	/* update TD status field before transmitting */
+	td->status = USB_TD_INPROGRESS;
+	/* update actual frame time object with the actual transmission */
+	usb->actual_frame->total_bytes += (len + PROTOCOL_OVERHEAD);
+	fhci_add_td_to_frame(usb->actual_frame, td);
+
+	if (usb->port_status != FHCI_PORT_FULL &&
+			usb->port_status != FHCI_PORT_LOW) {
+		pkt->status = USB_TD_TX_ER_TIMEOUT;
+		pkt->len = 0;
+		fhci_transaction_confirm(usb, pkt);
+	} else if (fhci_host_transaction(usb, pkt, td->type, ed->dev_addr,
+			ed->ep_addr, ed->mode, ed->speed, td->toggle)) {
+		/* remove TD from actual frame */
+		list_del_init(&td->frame_lh);
+		td->status = USB_TD_OK;
+		if (pkt->info & PKT_DUMMY_PACKET)
+			cq_put(&usb->ep0->dummy_packets_Q, pkt->data);
+		recycle_frame(usb, pkt);
+		usb->actual_frame->total_bytes -= (len + PROTOCOL_OVERHEAD);
+		fhci_err(usb->fhci, "host transaction failed\n");
+		return -1;
+	}
+
+	return len;
+}
+
+static void move_head_to_tail(struct list_head *list)
+{
+	struct list_head *node = list->next;
+
+	if (!list_empty(list)) {
+		list_move_tail(node, list);
+	}
+}
+
+/*
+ * This function goes through the endpoint list and schedules the
+ * transactions within this list
+ */
+static int scan_ed_list(struct fhci_usb *usb,
+			struct list_head *list, enum fhci_tf_mode list_type)
+{
+	static const int frame_part[4] = {
+		[FHCI_TF_CTRL] = MAX_BYTES_PER_FRAME,
+		[FHCI_TF_ISO] = (MAX_BYTES_PER_FRAME *
+				 MAX_PERIODIC_FRAME_USAGE) / 100,
+		[FHCI_TF_BULK] = MAX_BYTES_PER_FRAME,
+		[FHCI_TF_INTR] = (MAX_BYTES_PER_FRAME *
+				  MAX_PERIODIC_FRAME_USAGE) / 100
+	};
+	struct ed *ed;
+	struct td *td;
+	int ans = 1;
+	u32 save_transaction_time = usb->sw_transaction_time;
+
+	list_for_each_entry(ed, list, node) {
+		td = ed->td_head;
+
+		if (!td || td->status == USB_TD_INPROGRESS)
+			continue;
+
+		if (ed->state != FHCI_ED_OPER) {
+			if (ed->state == FHCI_ED_URB_DEL) {
+				td->status = USB_TD_OK;
+				fhci_move_td_from_ed_to_done_list(usb, ed);
+				ed->state = FHCI_ED_SKIP;
+			}
+			continue;
+		}
+
+		/*
+		 * if it isn't interrupt pipe or it is not iso pipe and the
+		 * interval time passed
+		 */
+		if ((list_type == FHCI_TF_INTR || list_type == FHCI_TF_ISO) &&
+				(((usb->actual_frame->frame_num -
+				   td->start_frame) & 0x7ff) < td->interval))
+			continue;
+
+		if (add_packet(usb, ed, td) < 0)
+			continue;
+
+		/* update time stamps in the TD */
+		td->start_frame = usb->actual_frame->frame_num;
+		usb->sw_transaction_time += save_transaction_time;
+
+		if (usb->actual_frame->total_bytes >=
+					usb->max_bytes_per_frame) {
+			usb->actual_frame->frame_status =
+				FRAME_DATA_END_TRANSMISSION;
+			fhci_push_dummy_bd(usb->ep0);
+			ans = 0;
+			break;
+		}
+
+		if (usb->actual_frame->total_bytes >= frame_part[list_type])
+			break;
+	}
+
+	/* be fair to each ED(move list head around) */
+	move_head_to_tail(list);
+	usb->sw_transaction_time = save_transaction_time;
+
+	return ans;
+}
+
+static u32 rotate_frames(struct fhci_usb *usb)
+{
+	struct fhci_hcd *fhci = usb->fhci;
+
+	if (!list_empty(&usb->actual_frame->tds_list)) {
+		if ((((in_be16(&fhci->pram->frame_num) & 0x07ff) -
+		      usb->actual_frame->frame_num) & 0x7ff) > 5)
+			fhci_flush_actual_frame(usb);
+		else
+			return -EINVAL;
+	}
+
+	usb->actual_frame->frame_status = FRAME_IS_PREPARED;
+	usb->actual_frame->frame_num = in_be16(&fhci->pram->frame_num) & 0x7ff;
+	usb->actual_frame->total_bytes = 0;
+
+	return 0;
+}
+
+/*
+ * This function schedule the USB transaction and will process the
+ * endpoint in the following order: iso, interrupt, control and bulk.
+ */
+void fhci_schedule_transactions(struct fhci_usb *usb)
+{
+	int left = 1;
+
+	if (usb->actual_frame->frame_status & FRAME_END_TRANSMISSION)
+		if (rotate_frames(usb) != 0)
+			return;
+
+	if (usb->actual_frame->frame_status & FRAME_END_TRANSMISSION)
+		return;
+
+	if (usb->actual_frame->total_bytes == 0) {
+		/*
+		 * schedule the next available ISO transfer
+		 *or next stage of the ISO transfer
+		 */
+		scan_ed_list(usb, &usb->hc_list->iso_list, FHCI_TF_ISO);
+
+		/*
+		 * schedule the next available interrupt transfer or
+		 * the next stage of the interrupt transfer
+		 */
+		scan_ed_list(usb, &usb->hc_list->intr_list, FHCI_TF_INTR);
+
+		/*
+		 * schedule the next available control transfer
+		 * or the next stage of the control transfer
+		 */
+		left = scan_ed_list(usb, &usb->hc_list->ctrl_list,
+				    FHCI_TF_CTRL);
+	}
+
+	/*
+	 * schedule the next available bulk transfer or the next stage of the
+	 * bulk transfer
+	 */
+	if (left > 0)
+		scan_ed_list(usb, &usb->hc_list->bulk_list, FHCI_TF_BULK);
+}
+
+/* Handles SOF interrupt */
+static void sof_interrupt(struct fhci_hcd *fhci)
+{
+	struct fhci_usb *usb = fhci->usb_lld;
+
+	if ((usb->port_status == FHCI_PORT_DISABLED) &&
+	    (usb->vroot_hub->port.wPortStatus & USB_PORT_STAT_CONNECTION) &&
+	    !(usb->vroot_hub->port.wPortChange & USB_PORT_STAT_C_CONNECTION)) {
+		if (usb->vroot_hub->port.wPortStatus & USB_PORT_STAT_LOW_SPEED)
+			usb->port_status = FHCI_PORT_LOW;
+		else
+			usb->port_status = FHCI_PORT_FULL;
+		/* Disable IDLE */
+		usb->saved_msk &= ~USB_E_IDLE_MASK;
+		out_be16(&usb->fhci->regs->usb_usbmr, usb->saved_msk);
+	}
+
+	gtm_set_exact_timer16(fhci->timer, usb->max_frame_usage, false);
+
+	fhci_host_transmit_actual_frame(usb);
+	usb->actual_frame->frame_status = FRAME_IS_TRANSMITTED;
+
+	fhci_schedule_transactions(usb);
+}
+
+/* Handles device disconnected interrupt on port */
+void fhci_device_disconnected_interrupt(struct fhci_hcd *fhci)
+{
+	struct fhci_usb *usb = fhci->usb_lld;
+
+	fhci_dbg(fhci, "-> %s\n", __func__);
+
+	fhci_usb_disable_interrupt(usb);
+	clrbits8(&usb->fhci->regs->usb_usmod, USB_MODE_LSS);
+	usb->port_status = FHCI_PORT_DISABLED;
+
+	fhci_stop_sof_timer(fhci);
+
+	/* Enable IDLE since we want to know if something comes along */
+	usb->saved_msk |= USB_E_IDLE_MASK;
+	out_be16(&usb->fhci->regs->usb_usbmr, usb->saved_msk);
+
+	usb->vroot_hub->port.wPortStatus &= ~USB_PORT_STAT_CONNECTION;
+	usb->vroot_hub->port.wPortChange |= USB_PORT_STAT_C_CONNECTION;
+	usb->max_bytes_per_frame = 0;
+	fhci_usb_enable_interrupt(usb);
+
+	fhci_dbg(fhci, "<- %s\n", __func__);
+}
+
+/* detect a new device connected on the USB port */
+void fhci_device_connected_interrupt(struct fhci_hcd *fhci)
+{
+
+	struct fhci_usb *usb = fhci->usb_lld;
+	int state;
+	int ret;
+
+	fhci_dbg(fhci, "-> %s\n", __func__);
+
+	fhci_usb_disable_interrupt(usb);
+	state = fhci_ioports_check_bus_state(fhci);
+
+	/* low-speed device was connected to the USB port */
+	if (state == 1) {
+		ret = qe_usb_clock_set(fhci->lowspeed_clk, USB_CLOCK >> 3);
+		if (ret) {
+			fhci_warn(fhci, "Low-Speed device is not supported, "
+				  "try use BRGx\n");
+			goto out;
+		}
+
+		usb->port_status = FHCI_PORT_LOW;
+		setbits8(&usb->fhci->regs->usb_usmod, USB_MODE_LSS);
+		usb->vroot_hub->port.wPortStatus |=
+		    (USB_PORT_STAT_LOW_SPEED |
+		     USB_PORT_STAT_CONNECTION);
+		usb->vroot_hub->port.wPortChange |=
+		    USB_PORT_STAT_C_CONNECTION;
+		usb->max_bytes_per_frame =
+		    (MAX_BYTES_PER_FRAME >> 3) - 7;
+		fhci_port_enable(usb);
+	} else if (state == 2) {
+		ret = qe_usb_clock_set(fhci->fullspeed_clk, USB_CLOCK);
+		if (ret) {
+			fhci_warn(fhci, "Full-Speed device is not supported, "
+				  "try use CLKx\n");
+			goto out;
+		}
+
+		usb->port_status = FHCI_PORT_FULL;
+		clrbits8(&usb->fhci->regs->usb_usmod, USB_MODE_LSS);
+		usb->vroot_hub->port.wPortStatus &=
+		    ~USB_PORT_STAT_LOW_SPEED;
+		usb->vroot_hub->port.wPortStatus |=
+		    USB_PORT_STAT_CONNECTION;
+		usb->vroot_hub->port.wPortChange |=
+		    USB_PORT_STAT_C_CONNECTION;
+		usb->max_bytes_per_frame = (MAX_BYTES_PER_FRAME - 15);
+		fhci_port_enable(usb);
+	}
+out:
+	fhci_usb_enable_interrupt(usb);
+	fhci_dbg(fhci, "<- %s\n", __func__);
+}
+
+irqreturn_t fhci_frame_limit_timer_irq(int irq, void *_hcd)
+{
+	struct usb_hcd *hcd = _hcd;
+	struct fhci_hcd *fhci = hcd_to_fhci(hcd);
+	struct fhci_usb *usb = fhci->usb_lld;
+
+	spin_lock(&fhci->lock);
+
+	gtm_set_exact_timer16(fhci->timer, 1000, false);
+
+	if (usb->actual_frame->frame_status == FRAME_IS_TRANSMITTED) {
+		usb->actual_frame->frame_status = FRAME_TIMER_END_TRANSMISSION;
+		fhci_push_dummy_bd(usb->ep0);
+	}
+
+	fhci_schedule_transactions(usb);
+
+	spin_unlock(&fhci->lock);
+
+	return IRQ_HANDLED;
+}
+
+/* Cancel transmission on the USB endpoint */
+static void abort_transmission(struct fhci_usb *usb)
+{
+	fhci_dbg(usb->fhci, "-> %s\n", __func__);
+	/* issue stop Tx command */
+	qe_issue_cmd(QE_USB_STOP_TX, QE_CR_SUBBLOCK_USB, EP_ZERO, 0);
+	/* flush Tx FIFOs */
+	out_8(&usb->fhci->regs->usb_uscom, USB_CMD_FLUSH_FIFO | EP_ZERO);
+	udelay(1000);
+	/* reset Tx BDs */
+	fhci_flush_bds(usb);
+	/* issue restart Tx command */
+	qe_issue_cmd(QE_USB_RESTART_TX, QE_CR_SUBBLOCK_USB, EP_ZERO, 0);
+	fhci_dbg(usb->fhci, "<- %s\n", __func__);
+}
+
+irqreturn_t fhci_irq(struct usb_hcd *hcd)
+{
+	struct fhci_hcd *fhci = hcd_to_fhci(hcd);
+	struct fhci_usb *usb;
+	u16 usb_er = 0;
+	unsigned long flags;
+
+	spin_lock_irqsave(&fhci->lock, flags);
+
+	usb = fhci->usb_lld;
+
+	usb_er |= in_be16(&usb->fhci->regs->usb_usber) &
+		  in_be16(&usb->fhci->regs->usb_usbmr);
+
+	/* clear event bits for next time */
+	out_be16(&usb->fhci->regs->usb_usber, usb_er);
+
+	fhci_dbg_isr(fhci, usb_er);
+
+	if (usb_er & USB_E_RESET_MASK) {
+		if ((usb->port_status == FHCI_PORT_FULL) ||
+				(usb->port_status == FHCI_PORT_LOW)) {
+			fhci_device_disconnected_interrupt(fhci);
+			usb_er &= ~USB_E_IDLE_MASK;
+		} else if (usb->port_status == FHCI_PORT_WAITING) {
+			usb->port_status = FHCI_PORT_DISCONNECTING;
+
+			/* Turn on IDLE since we want to disconnect */
+			usb->saved_msk |= USB_E_IDLE_MASK;
+			out_be16(&usb->fhci->regs->usb_usber,
+				 usb->saved_msk);
+		} else if (usb->port_status == FHCI_PORT_DISABLED) {
+			if (fhci_ioports_check_bus_state(fhci) == 1)
+				fhci_device_connected_interrupt(fhci);
+		}
+		usb_er &= ~USB_E_RESET_MASK;
+	}
+
+	if (usb_er & USB_E_MSF_MASK) {
+		abort_transmission(fhci->usb_lld);
+		usb_er &= ~USB_E_MSF_MASK;
+	}
+
+	if (usb_er & (USB_E_SOF_MASK | USB_E_SFT_MASK)) {
+		sof_interrupt(fhci);
+		usb_er &= ~(USB_E_SOF_MASK | USB_E_SFT_MASK);
+	}
+
+	if (usb_er & USB_E_TXB_MASK) {
+		fhci_tx_conf_interrupt(fhci->usb_lld);
+		usb_er &= ~USB_E_TXB_MASK;
+	}
+
+	if (usb_er & USB_E_TXE1_MASK) {
+		fhci_tx_conf_interrupt(fhci->usb_lld);
+		usb_er &= ~USB_E_TXE1_MASK;
+	}
+
+	if (usb_er & USB_E_IDLE_MASK) {
+		if (usb->port_status == FHCI_PORT_DISABLED) {
+			usb_er &= ~USB_E_RESET_MASK;
+			fhci_device_connected_interrupt(fhci);
+		} else if (usb->port_status ==
+				FHCI_PORT_DISCONNECTING) {
+			/* XXX usb->port_status = FHCI_PORT_WAITING; */
+			/* Disable IDLE */
+			usb->saved_msk &= ~USB_E_IDLE_MASK;
+			out_be16(&usb->fhci->regs->usb_usbmr,
+				 usb->saved_msk);
+		} else {
+			fhci_dbg_isr(fhci, -1);
+		}
+
+		usb_er &= ~USB_E_IDLE_MASK;
+	}
+
+	spin_unlock_irqrestore(&fhci->lock, flags);
+
+	return IRQ_HANDLED;
+}
+
+
+/*
+ * Process normal completions(error or success) and clean the schedule.
+ *
+ * This is the main path for handing urbs back to drivers. The only other patth
+ * is process_del_list(),which unlinks URBs by scanning EDs,instead of scanning
+ * the (re-reversed) done list as this does.
+ */
+static void process_done_list(unsigned long data)
+{
+	struct urb *urb;
+	struct ed *ed;
+	struct td *td;
+	struct urb_priv *urb_priv;
+	struct fhci_hcd *fhci = (struct fhci_hcd *)data;
+
+	disable_irq(fhci->timer->irq);
+	disable_irq(fhci_to_hcd(fhci)->irq);
+	spin_lock(&fhci->lock);
+
+	td = fhci_remove_td_from_done_list(fhci->hc_list);
+	while (td != NULL) {
+		urb = td->urb;
+		urb_priv = urb->hcpriv;
+		ed = td->ed;
+
+		/* update URB's length and status from TD */
+		fhci_done_td(urb, td);
+		urb_priv->tds_cnt++;
+
+		/*
+		 * if all this urb's TDs are done, call complete()
+		 * Interrupt transfers are the onley special case:
+		 * they are reissued,until "deleted" by usb_unlink_urb
+		 * (real work done in a SOF intr, by process_del_list)
+		 */
+		if (urb_priv->tds_cnt == urb_priv->num_of_tds) {
+			fhci_urb_complete_free(fhci, urb);
+		} else if (urb_priv->state == URB_DEL &&
+				ed->state == FHCI_ED_SKIP) {
+			fhci_del_ed_list(fhci, ed);
+			ed->state = FHCI_ED_OPER;
+		} else if (ed->state == FHCI_ED_HALTED) {
+			urb_priv->state = URB_DEL;
+			ed->state = FHCI_ED_URB_DEL;
+			fhci_del_ed_list(fhci, ed);
+			ed->state = FHCI_ED_OPER;
+		}
+
+		td = fhci_remove_td_from_done_list(fhci->hc_list);
+	}
+
+	spin_unlock(&fhci->lock);
+	enable_irq(fhci->timer->irq);
+	enable_irq(fhci_to_hcd(fhci)->irq);
+}
+
+DECLARE_TASKLET(fhci_tasklet, process_done_list, 0);
+
+/* transfer complted callback */
+u32 fhci_transfer_confirm_callback(struct fhci_hcd *fhci)
+{
+	if (!fhci->process_done_task->state)
+		tasklet_schedule(fhci->process_done_task);
+	return 0;
+}
+
+/*
+ * adds urb to the endpoint descriptor list
+ * arguments:
+ * fhci		data structure for the Low level host controller
+ * ep		USB Host endpoint data structure
+ * urb		USB request block data structure
+ */
+void fhci_queue_urb(struct fhci_hcd *fhci, struct urb *urb)
+{
+	struct ed *ed = urb->ep->hcpriv;
+	struct urb_priv *urb_priv = urb->hcpriv;
+	u32 data_len = urb->transfer_buffer_length;
+	int urb_state = 0;
+	int toggle = 0;
+	struct td *td;
+	u8 *data;
+	u16 cnt = 0;
+
+	if (ed == NULL) {
+		ed = fhci_get_empty_ed(fhci);
+		ed->dev_addr = usb_pipedevice(urb->pipe);
+		ed->ep_addr = usb_pipeendpoint(urb->pipe);
+		switch (usb_pipetype(urb->pipe)) {
+		case PIPE_CONTROL:
+			ed->mode = FHCI_TF_CTRL;
+			break;
+		case PIPE_BULK:
+			ed->mode = FHCI_TF_BULK;
+			break;
+		case PIPE_INTERRUPT:
+			ed->mode = FHCI_TF_INTR;
+			break;
+		case PIPE_ISOCHRONOUS:
+			ed->mode = FHCI_TF_ISO;
+			break;
+		default:
+			break;
+		}
+		ed->speed = (urb->dev->speed == USB_SPEED_LOW) ?
+			FHCI_LOW_SPEED : FHCI_FULL_SPEED;
+		ed->max_pkt_size = usb_maxpacket(urb->dev,
+			urb->pipe, usb_pipeout(urb->pipe));
+		urb->ep->hcpriv = ed;
+		fhci_dbg(fhci, "new ep speed=%d max_pkt_size=%d\n",
+			 ed->speed, ed->max_pkt_size);
+	}
+
+	/* for ISO transfer calculate start frame index */
+	if (ed->mode == FHCI_TF_ISO) {
+		/* Ignore the possibility of underruns */
+		urb->start_frame = ed->td_head ? ed->next_iso :
+						 get_frame_num(fhci);
+		ed->next_iso = (urb->start_frame + urb->interval *
+				urb->number_of_packets) & 0x07ff;
+	}
+
+	/*
+	 * OHCI handles the DATA toggle itself,we just use the USB
+	 * toggle bits
+	 */
+	if (usb_gettoggle(urb->dev, usb_pipeendpoint(urb->pipe),
+			  usb_pipeout(urb->pipe)))
+		toggle = USB_TD_TOGGLE_CARRY;
+	else {
+		toggle = USB_TD_TOGGLE_DATA0;
+		usb_settoggle(urb->dev, usb_pipeendpoint(urb->pipe),
+			      usb_pipeout(urb->pipe), 1);
+	}
+
+	urb_priv->tds_cnt = 0;
+	urb_priv->ed = ed;
+	if (data_len > 0)
+		data = urb->transfer_buffer;
+	else
+		data = NULL;
+
+	switch (ed->mode) {
+	case FHCI_TF_BULK:
+		if (urb->transfer_flags & URB_ZERO_PACKET &&
+				urb->transfer_buffer_length > 0 &&
+				((urb->transfer_buffer_length %
+				usb_maxpacket(urb->dev, urb->pipe,
+				usb_pipeout(urb->pipe))) == 0))
+			urb_state = US_BULK0;
+		while (data_len > 4096) {
+			td = fhci_td_fill(fhci, urb, urb_priv, ed, cnt,
+				usb_pipeout(urb->pipe) ? FHCI_TA_OUT :
+							 FHCI_TA_IN,
+				cnt ? USB_TD_TOGGLE_CARRY :
+				      toggle,
+				data, 4096, 0, 0, true);
+			data += 4096;
+			data_len -= 4096;
+			cnt++;
+		}
+
+		td = fhci_td_fill(fhci, urb, urb_priv, ed, cnt,
+			usb_pipeout(urb->pipe) ? FHCI_TA_OUT : FHCI_TA_IN,
+			cnt ? USB_TD_TOGGLE_CARRY : toggle,
+			data, data_len, 0, 0, true);
+		cnt++;
+
+		if (urb->transfer_flags & URB_ZERO_PACKET &&
+				cnt < urb_priv->num_of_tds) {
+			td = fhci_td_fill(fhci, urb, urb_priv, ed, cnt,
+				usb_pipeout(urb->pipe) ? FHCI_TA_OUT :
+							 FHCI_TA_IN,
+				USB_TD_TOGGLE_CARRY, NULL, 0, 0, 0, true);
+			cnt++;
+		}
+		break;
+	case FHCI_TF_INTR:
+		urb->start_frame = get_frame_num(fhci) + 1;
+		td = fhci_td_fill(fhci, urb, urb_priv, ed, cnt++,
+			usb_pipeout(urb->pipe) ? FHCI_TA_OUT : FHCI_TA_IN,
+			USB_TD_TOGGLE_DATA0, data, data_len,
+			urb->interval, urb->start_frame, true);
+		break;
+	case FHCI_TF_CTRL:
+		ed->dev_addr = usb_pipedevice(urb->pipe);
+		ed->max_pkt_size = usb_maxpacket(urb->dev, urb->pipe,
+			usb_pipeout(urb->pipe));
+		/* setup stage */
+		td = fhci_td_fill(fhci, urb, urb_priv, ed, cnt++, FHCI_TA_SETUP,
+			USB_TD_TOGGLE_DATA0, urb->setup_packet, 8, 0, 0, true);
+
+		/* data stage */
+		if (data_len > 0) {
+			td = fhci_td_fill(fhci, urb, urb_priv, ed, cnt++,
+				usb_pipeout(urb->pipe) ? FHCI_TA_OUT :
+							 FHCI_TA_IN,
+				USB_TD_TOGGLE_DATA1, data, data_len, 0, 0,
+				true);
+		}
+
+		/* status stage */
+		if (data_len > 0)
+			td = fhci_td_fill(fhci, urb, urb_priv, ed, cnt++,
+				(usb_pipeout(urb->pipe) ? FHCI_TA_IN :
+							  FHCI_TA_OUT),
+				USB_TD_TOGGLE_DATA1, data, 0, 0, 0, true);
+		else
+			 td = fhci_td_fill(fhci, urb, urb_priv, ed, cnt++,
+				FHCI_TA_IN,
+				USB_TD_TOGGLE_DATA1, data, 0, 0, 0, true);
+
+		urb_state = US_CTRL_SETUP;
+		break;
+	case FHCI_TF_ISO:
+		for (cnt = 0; cnt < urb->number_of_packets; cnt++) {
+			u16 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 &= 0x07ff;
+			td = fhci_td_fill(fhci, urb, urb_priv, ed, cnt,
+				usb_pipeout(urb->pipe) ? FHCI_TA_OUT :
+							 FHCI_TA_IN,
+				USB_TD_TOGGLE_DATA0,
+				data + urb->iso_frame_desc[cnt].offset,
+				urb->iso_frame_desc[cnt].length,
+				urb->interval, frame, true);
+		}
+		break;
+	default:
+		break;
+	}
+
+	/*
+	 * set the state of URB
+	 * control pipe:3 states -- setup,data,status
+	 * interrupt and bulk pipe:1 state -- data
+	 */
+	urb->pipe &= ~0x1f;
+	urb->pipe |= urb_state & 0x1f;
+
+	urb_priv->state = URB_INPROGRESS;
+
+	if (!ed->td_head) {
+		ed->state = FHCI_ED_OPER;
+		switch (ed->mode) {
+		case FHCI_TF_CTRL:
+			list_add(&ed->node, &fhci->hc_list->ctrl_list);
+			break;
+		case FHCI_TF_BULK:
+			list_add(&ed->node, &fhci->hc_list->bulk_list);
+			break;
+		case FHCI_TF_INTR:
+			list_add(&ed->node, &fhci->hc_list->intr_list);
+			break;
+		case FHCI_TF_ISO:
+			list_add(&ed->node, &fhci->hc_list->iso_list);
+			break;
+		default:
+			break;
+		}
+	}
+
+	fhci_add_tds_to_ed(ed, urb_priv->tds, urb_priv->num_of_tds);
+	fhci->active_urbs++;
+}