/*
 * Freescale QUICC Engine USB Host Controller Driver
 *
 * Copyright (c) Freescale Semicondutor, Inc. 2006.
 *               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>
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 */

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/list.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include "fhci.h"

/* maps the hardware error code to the USB error code */
static int status_to_error(u32 status)
{
        if (status == USB_TD_OK)
                return 0;
        else if (status & USB_TD_RX_ER_CRC)
                return -EILSEQ;
        else if (status & USB_TD_RX_ER_NONOCT)
                return -EPROTO;
        else if (status & USB_TD_RX_ER_OVERUN)
                return -ECOMM;
        else if (status & USB_TD_RX_ER_BITSTUFF)
                return -EPROTO;
        else if (status & USB_TD_RX_ER_PID)
                return -EILSEQ;
        else if (status & (USB_TD_TX_ER_NAK | USB_TD_TX_ER_TIMEOUT))
                return -ETIMEDOUT;
        else if (status & USB_TD_TX_ER_STALL)
                return -EPIPE;
        else if (status & USB_TD_TX_ER_UNDERUN)
                return -ENOSR;
        else if (status & USB_TD_RX_DATA_UNDERUN)
                return -EREMOTEIO;
        else if (status & USB_TD_RX_DATA_OVERUN)
                return -EOVERFLOW;
        else
                return -EINVAL;
}

void fhci_add_td_to_frame(struct fhci_time_frame *frame, struct td *td)
{
        list_add_tail(&td->frame_lh, &frame->tds_list);
}

void fhci_add_tds_to_ed(struct ed *ed, struct td **td_list, int number)
{
        int i;

        for (i = 0; i < number; i++) {
                struct td *td = td_list[i];
                list_add_tail(&td->node, &ed->td_list);
        }
        if (ed->td_head == NULL)
                ed->td_head = td_list[0];
}

static struct td *peek_td_from_ed(struct ed *ed)
{
        struct td *td;

        if (!list_empty(&ed->td_list))
                td = list_entry(ed->td_list.next, struct td, node);
        else
                td = NULL;

        return td;
}

struct td *fhci_remove_td_from_frame(struct fhci_time_frame *frame)
{
        struct td *td;

        if (!list_empty(&frame->tds_list)) {
                td = list_entry(frame->tds_list.next, struct td, frame_lh);
                list_del_init(frame->tds_list.next);
        } else
                td = NULL;

        return td;
}

struct td *fhci_peek_td_from_frame(struct fhci_time_frame *frame)
{
        struct td *td;

        if (!list_empty(&frame->tds_list))
                td = list_entry(frame->tds_list.next, struct td, frame_lh);
        else
                td = NULL;

        return td;
}

struct td *fhci_remove_td_from_ed(struct ed *ed)
{
        struct td *td;

        if (!list_empty(&ed->td_list)) {
                td = list_entry(ed->td_list.next, struct td, node);
                list_del_init(ed->td_list.next);

                /* if this TD was the ED's head, find next TD */
                if (!list_empty(&ed->td_list))
                        ed->td_head = list_entry(ed->td_list.next, struct td,
                                                 node);
                else
                        ed->td_head = NULL;
        } else
                td = NULL;

        return td;
}

struct td *fhci_remove_td_from_done_list(struct fhci_controller_list *p_list)
{
        struct td *td;

        if (!list_empty(&p_list->done_list)) {
                td = list_entry(p_list->done_list.next, struct td, node);
                list_del_init(p_list->done_list.next);
        } else
                td = NULL;

        return td;
}

void fhci_move_td_from_ed_to_done_list(struct fhci_usb *usb, struct ed *ed)
{
        struct td *td;

        td = ed->td_head;
        list_del_init(&td->node);

        /* If this TD was the ED's head,find next TD */
        if (!list_empty(&ed->td_list))
                ed->td_head = list_entry(ed->td_list.next, struct td, node);
        else {
                ed->td_head = NULL;
                ed->state = FHCI_ED_SKIP;
        }
        ed->toggle_carry = td->toggle;
        list_add_tail(&td->node, &usb->hc_list->done_list);
        if (td->ioc)
                usb->transfer_confirm(usb->fhci);
}

/* free done FHCI URB resource such as ED and TD */
static void free_urb_priv(struct fhci_hcd *fhci, struct urb *urb)
{
        int i;
        struct urb_priv *urb_priv = urb->hcpriv;
        struct ed *ed = urb_priv->ed;

        for (i = 0; i < urb_priv->num_of_tds; i++) {
                list_del_init(&urb_priv->tds[i]->node);
                fhci_recycle_empty_td(fhci, urb_priv->tds[i]);
        }

        /* if this TD was the ED's head,find the next TD */
        if (!list_empty(&ed->td_list))
                ed->td_head = list_entry(ed->td_list.next, struct td, node);
        else
                ed->td_head = NULL;

        kfree(urb_priv->tds);
        kfree(urb_priv);
        urb->hcpriv = NULL;

        /* if this TD was the ED's head,find next TD */
        if (ed->td_head == NULL)
                list_del_init(&ed->node);
        fhci->active_urbs--;
}

/* this routine called to complete and free done URB */
void fhci_urb_complete_free(struct fhci_hcd *fhci, struct urb *urb)
{
        free_urb_priv(fhci, urb);

        if (urb->status == -EINPROGRESS) {
                if (urb->actual_length != urb->transfer_buffer_length &&
                                urb->transfer_flags & URB_SHORT_NOT_OK)
                        urb->status = -EREMOTEIO;
                else
                        urb->status = 0;
        }

        usb_hcd_unlink_urb_from_ep(fhci_to_hcd(fhci), urb);

        spin_unlock(&fhci->lock);

        usb_hcd_giveback_urb(fhci_to_hcd(fhci), urb, urb->status);

        spin_lock(&fhci->lock);
}

/*
 * caculate transfer length/stats and update the urb
 * Precondition: irqsafe(only for urb-?status locking)
 */
void fhci_done_td(struct urb *urb, struct td *td)
{
        struct ed *ed = td->ed;
        u32 cc = td->status;

        /* ISO...drivers see per-TD length/status */
        if (ed->mode == FHCI_TF_ISO) {
                u32 len;
                if (!(urb->transfer_flags & URB_SHORT_NOT_OK &&
                                cc == USB_TD_RX_DATA_UNDERUN))
                        cc = USB_TD_OK;

                if (usb_pipeout(urb->pipe))
                        len = urb->iso_frame_desc[td->iso_index].length;
                else
                        len = td->actual_len;

                urb->actual_length += len;
                urb->iso_frame_desc[td->iso_index].actual_length = len;
                urb->iso_frame_desc[td->iso_index].status =
                        status_to_error(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 {
                if (td->error_cnt >= 3)
                        urb->error_count = 3;

                /* control endpoint only have soft stalls */

                /* update packet status if needed(short may be ok) */
                if (!(urb->transfer_flags & URB_SHORT_NOT_OK) &&
                                cc == USB_TD_RX_DATA_UNDERUN) {
                        ed->state = FHCI_ED_OPER;
                        cc = USB_TD_OK;
                }
                if (cc != USB_TD_OK) {
                        if (urb->status == -EINPROGRESS)
                                urb->status = status_to_error(cc);
                }

                /* count all non-empty packets except control SETUP packet */
                if (td->type != FHCI_TA_SETUP || td->iso_index != 0)
                        urb->actual_length += td->actual_len;
        }
}

/* there are some pedning request to unlink */
void fhci_del_ed_list(struct fhci_hcd *fhci, struct ed *ed)
{
        struct td *td = peek_td_from_ed(ed);
        struct urb *urb = td->urb;
        struct urb_priv *urb_priv = urb->hcpriv;

        if (urb_priv->state == URB_DEL) {
                td = fhci_remove_td_from_ed(ed);
                /* HC may have partly processed this TD */
                if (td->status != USB_TD_INPROGRESS)
                        fhci_done_td(urb, td);

                /* URB is done;clean up */
                if (++(urb_priv->tds_cnt) == urb_priv->num_of_tds)
                        fhci_urb_complete_free(fhci, urb);
        }
}