drivers/usb/host/fhci-sched.c

root/drivers/usb/host/fhci-sched.c
// 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;

        /* calculate 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_OLD(fhci_tasklet, process_done_list);

/* transfer completed 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;
        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_endpoint_maxp(&urb->ep->desc);
                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_endpoint_maxp(&urb->ep->desc)) == 0))
                        urb_state = US_BULK0;
                while (data_len > 4096) {
                        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++;
                }

                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) {
                        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;
                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_endpoint_maxp(&urb->ep->desc);

                /* setup stage */
                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) {
                        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)
                        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
                         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;
                        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++;
}
Linux
