/*
   * 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);
  	}
  }