text: /*
   * Renesas USB driver
   *
   * Copyright (C) 2011 Renesas Solutions Corp.
   * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
   *
   * This program is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   * GNU General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
   *
   */
  #include <linux/delay.h>
  #include <linux/io.h>
  #include <linux/scatterlist.h>
  #include "common.h"
  #include "pipe.h"
  
  #define usbhsf_get_cfifo(p)	(&((p)->fifo_info.cfifo))
  #define usbhsf_get_d0fifo(p)	(&((p)->fifo_info.d0fifo))
  #define usbhsf_get_d1fifo(p)	(&((p)->fifo_info.d1fifo))
  #define usbhsf_is_cfifo(p, f)	(usbhsf_get_cfifo(p) == f)
  
  #define usbhsf_fifo_is_busy(f)	((f)->pipe) /* see usbhs_pipe_select_fifo */
  
  /*
   *		packet initialize
   */
  void usbhs_pkt_init(struct usbhs_pkt *pkt)
  {
  	INIT_LIST_HEAD(&pkt->node);
  }
  
  /*
   *		packet control function
   */
  static int usbhsf_null_handle(struct usbhs_pkt *pkt, int *is_done)
  {
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pkt->pipe);
  	struct device *dev = usbhs_priv_to_dev(priv);
  
  	dev_err(dev, "null handler\n");
  
  	return -EINVAL;
  }
  
  static struct usbhs_pkt_handle usbhsf_null_handler = {
  	.prepare = usbhsf_null_handle,
  	.try_run = usbhsf_null_handle,
  };
  
  void usbhs_pkt_push(struct usbhs_pipe *pipe, struct usbhs_pkt *pkt,
  		    void (*done)(struct usbhs_priv *priv,
  				 struct usbhs_pkt *pkt),
  		    void *buf, int len, int zero, int sequence)
  {
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct device *dev = usbhs_priv_to_dev(priv);
  	unsigned long flags;
  
  	if (!done) {
  		dev_err(dev, "no done function\n");
  		return;
  	}
  
  	/********************  spin lock ********************/
  	usbhs_lock(priv, flags);
  
  	if (!pipe->handler) {
  		dev_err(dev, "no handler function\n");
  		pipe->handler = &usbhsf_null_handler;
  	}
  
  	list_move_tail(&pkt->node, &pipe->list);
  
  	/*
  	 * each pkt must hold own handler.
  	 * because handler might be changed by its situation.
  	 * dma handler -> pio handler.
  	 */
  	pkt->pipe	= pipe;
  	pkt->buf	= buf;
  	pkt->handler	= pipe->handler;
  	pkt->length	= len;
  	pkt->zero	= zero;
  	pkt->actual	= 0;
  	pkt->done	= done;
  	pkt->sequence	= sequence;
  
  	usbhs_unlock(priv, flags);
  	/********************  spin unlock ******************/
  }
  
  static void __usbhsf_pkt_del(struct usbhs_pkt *pkt)
  {
  	list_del_init(&pkt->node);
  }
  
  static struct usbhs_pkt *__usbhsf_pkt_get(struct usbhs_pipe *pipe)
  {
  	if (list_empty(&pipe->list))
  		return NULL;
  
  	return list_first_entry(&pipe->list, struct usbhs_pkt, node);
  }
  
  static void usbhsf_fifo_clear(struct usbhs_pipe *pipe,
  			      struct usbhs_fifo *fifo);
  static void usbhsf_fifo_unselect(struct usbhs_pipe *pipe,
  				 struct usbhs_fifo *fifo);
  static struct dma_chan *usbhsf_dma_chan_get(struct usbhs_fifo *fifo,
  					    struct usbhs_pkt *pkt);
  #define usbhsf_dma_map(p)	__usbhsf_dma_map_ctrl(p, 1)
  #define usbhsf_dma_unmap(p)	__usbhsf_dma_map_ctrl(p, 0)
  static int __usbhsf_dma_map_ctrl(struct usbhs_pkt *pkt, int map);
  struct usbhs_pkt *usbhs_pkt_pop(struct usbhs_pipe *pipe, struct usbhs_pkt *pkt)
  {
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct usbhs_fifo *fifo = usbhs_pipe_to_fifo(pipe);
  	unsigned long flags;
  
  	/********************  spin lock ********************/
  	usbhs_lock(priv, flags);
  
  	usbhs_pipe_disable(pipe);
  
  	if (!pkt)
  		pkt = __usbhsf_pkt_get(pipe);
  
  	if (pkt) {
  		struct dma_chan *chan = NULL;
  
  		if (fifo)
  			chan = usbhsf_dma_chan_get(fifo, pkt);
  		if (chan) {
  			dmaengine_terminate_all(chan);
  			usbhsf_fifo_clear(pipe, fifo);
  			usbhsf_dma_unmap(pkt);
  		}
  
  		__usbhsf_pkt_del(pkt);
  	}
  
  	if (fifo)
  		usbhsf_fifo_unselect(pipe, fifo);
  
  	usbhs_unlock(priv, flags);
  	/********************  spin unlock ******************/
  
  	return pkt;
  }
  
  enum {
  	USBHSF_PKT_PREPARE,
  	USBHSF_PKT_TRY_RUN,
  	USBHSF_PKT_DMA_DONE,
  };
  
  static int usbhsf_pkt_handler(struct usbhs_pipe *pipe, int type)
  {
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct usbhs_pkt *pkt;
  	struct device *dev = usbhs_priv_to_dev(priv);
  	int (*func)(struct usbhs_pkt *pkt, int *is_done);
  	unsigned long flags;
  	int ret = 0;
  	int is_done = 0;
  
  	/********************  spin lock ********************/
  	usbhs_lock(priv, flags);
  
  	pkt = __usbhsf_pkt_get(pipe);
  	if (!pkt)
  		goto __usbhs_pkt_handler_end;
  
  	switch (type) {
  	case USBHSF_PKT_PREPARE:
  		func = pkt->handler->prepare;
  		break;
  	case USBHSF_PKT_TRY_RUN:
  		func = pkt->handler->try_run;
  		break;
  	case USBHSF_PKT_DMA_DONE:
  		func = pkt->handler->dma_done;
  		break;
  	default:
  		dev_err(dev, "unknown pkt handler\n");
  		goto __usbhs_pkt_handler_end;
  	}
  
  	if (likely(func))
  		ret = func(pkt, &is_done);
  
  	if (is_done)
  		__usbhsf_pkt_del(pkt);
  
  __usbhs_pkt_handler_end:
  	usbhs_unlock(priv, flags);
  	/********************  spin unlock ******************/
  
  	if (is_done) {
  		pkt->done(priv, pkt);
  		usbhs_pkt_start(pipe);
  	}
  
  	return ret;
  }
  
  void usbhs_pkt_start(struct usbhs_pipe *pipe)
  {
  	usbhsf_pkt_handler(pipe, USBHSF_PKT_PREPARE);
  }
  
  /*
   *		irq enable/disable function
   */
  #define usbhsf_irq_empty_ctrl(p, e) usbhsf_irq_callback_ctrl(p, irq_bempsts, e)
  #define usbhsf_irq_ready_ctrl(p, e) usbhsf_irq_callback_ctrl(p, irq_brdysts, e)
  #define usbhsf_irq_callback_ctrl(pipe, status, enable)			\
  	({								\
  		struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);	\
  		struct usbhs_mod *mod = usbhs_mod_get_current(priv);	\
  		u16 status = (1 << usbhs_pipe_number(pipe));		\
  		if (!mod)						\
  			return;						\
  		if (enable)						\
  			mod->status |= status;				\
  		else							\
  			mod->status &= ~status;				\
  		usbhs_irq_callback_update(priv, mod);			\
  	})
  
  static void usbhsf_tx_irq_ctrl(struct usbhs_pipe *pipe, int enable)
  {
  	/*
  	 * And DCP pipe can NOT use "ready interrupt" for "send"
  	 * it should use "empty" interrupt.
  	 * see
  	 *   "Operation" - "Interrupt Function" - "BRDY Interrupt"
  	 *
  	 * on the other hand, normal pipe can use "ready interrupt" for "send"
  	 * even though it is single/double buffer
  	 */
  	if (usbhs_pipe_is_dcp(pipe))
  		usbhsf_irq_empty_ctrl(pipe, enable);
  	else
  		usbhsf_irq_ready_ctrl(pipe, enable);
  }
  
  static void usbhsf_rx_irq_ctrl(struct usbhs_pipe *pipe, int enable)
  {
  	usbhsf_irq_ready_ctrl(pipe, enable);
  }
  
  /*
   *		FIFO ctrl
   */
  static void usbhsf_send_terminator(struct usbhs_pipe *pipe,
  				   struct usbhs_fifo *fifo)
  {
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  
  	usbhs_bset(priv, fifo->ctr, BVAL, BVAL);
  }
  
  static int usbhsf_fifo_barrier(struct usbhs_priv *priv,
  			       struct usbhs_fifo *fifo)
  {
  	int timeout = 1024;
  
  	do {
  		/* The FIFO port is accessible */
  		if (usbhs_read(priv, fifo->ctr) & FRDY)
  			return 0;
  
  		udelay(10);
  	} while (timeout--);
  
  	return -EBUSY;
  }
  
  static void usbhsf_fifo_clear(struct usbhs_pipe *pipe,
  			      struct usbhs_fifo *fifo)
  {
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	int ret = 0;
  
  	if (!usbhs_pipe_is_dcp(pipe)) {
  		/*
  		 * This driver checks the pipe condition first to avoid -EBUSY
  		 * from usbhsf_fifo_barrier() with about 10 msec delay in
  		 * the interrupt handler if the pipe is RX direction and empty.
  		 */
  		if (usbhs_pipe_is_dir_in(pipe))
  			ret = usbhs_pipe_is_accessible(pipe);
  		if (!ret)
  			ret = usbhsf_fifo_barrier(priv, fifo);
  	}
  
  	/*
  	 * if non-DCP pipe, this driver should set BCLR when
  	 * usbhsf_fifo_barrier() returns 0.
  	 */
  	if (!ret)
  		usbhs_write(priv, fifo->ctr, BCLR);
  }
  
  static int usbhsf_fifo_rcv_len(struct usbhs_priv *priv,
  			       struct usbhs_fifo *fifo)
  {
  	return usbhs_read(priv, fifo->ctr) & DTLN_MASK;
  }
  
  static void usbhsf_fifo_unselect(struct usbhs_pipe *pipe,
  				 struct usbhs_fifo *fifo)
  {
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  
  	usbhs_pipe_select_fifo(pipe, NULL);
  	usbhs_write(priv, fifo->sel, 0);
  }
  
  static int usbhsf_fifo_select(struct usbhs_pipe *pipe,
  			      struct usbhs_fifo *fifo,
  			      int write)
  {
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct device *dev = usbhs_priv_to_dev(priv);
  	int timeout = 1024;
  	u16 mask = ((1 << 5) | 0xF);		/* mask of ISEL | CURPIPE */
  	u16 base = usbhs_pipe_number(pipe);	/* CURPIPE */
  
  	if (usbhs_pipe_is_busy(pipe) ||
  	    usbhsf_fifo_is_busy(fifo))
  		return -EBUSY;
  
  	if (usbhs_pipe_is_dcp(pipe)) {
  		base |= (1 == write) << 5;	/* ISEL */
  
  		if (usbhs_mod_is_host(priv))
  			usbhs_dcp_dir_for_host(pipe, write);
  	}
  
  	/* "base" will be used below  */
  	if (usbhs_get_dparam(priv, has_sudmac) && !usbhsf_is_cfifo(priv, fifo))
  		usbhs_write(priv, fifo->sel, base);
  	else
  		usbhs_write(priv, fifo->sel, base | MBW_32);
  
  	/* check ISEL and CURPIPE value */
  	while (timeout--) {
  		if (base == (mask & usbhs_read(priv, fifo->sel))) {
  			usbhs_pipe_select_fifo(pipe, fifo);
  			return 0;
  		}
  		udelay(10);
  	}
  
  	dev_err(dev, "fifo select error\n");
  
  	return -EIO;
  }
  
  /*
   *		DCP status stage
   */
  static int usbhs_dcp_dir_switch_to_write(struct usbhs_pkt *pkt, int *is_done)
  {
  	struct usbhs_pipe *pipe = pkt->pipe;
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct usbhs_fifo *fifo = usbhsf_get_cfifo(priv); /* CFIFO */
  	struct device *dev = usbhs_priv_to_dev(priv);
  	int ret;
  
  	usbhs_pipe_disable(pipe);
  
  	ret = usbhsf_fifo_select(pipe, fifo, 1);
  	if (ret < 0) {
  		dev_err(dev, "%s() faile\n", __func__);
  		return ret;
  	}
  
  	usbhs_pipe_sequence_data1(pipe); /* DATA1 */
  
  	usbhsf_fifo_clear(pipe, fifo);
  	usbhsf_send_terminator(pipe, fifo);
  
  	usbhsf_fifo_unselect(pipe, fifo);
  
  	usbhsf_tx_irq_ctrl(pipe, 1);
  	usbhs_pipe_enable(pipe);
  
  	return ret;
  }
  
  static int usbhs_dcp_dir_switch_to_read(struct usbhs_pkt *pkt, int *is_done)
  {
  	struct usbhs_pipe *pipe = pkt->pipe;
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct usbhs_fifo *fifo = usbhsf_get_cfifo(priv); /* CFIFO */
  	struct device *dev = usbhs_priv_to_dev(priv);
  	int ret;
  
  	usbhs_pipe_disable(pipe);
  
  	ret = usbhsf_fifo_select(pipe, fifo, 0);
  	if (ret < 0) {
  		dev_err(dev, "%s() fail\n", __func__);
  		return ret;
  	}
  
  	usbhs_pipe_sequence_data1(pipe); /* DATA1 */
  	usbhsf_fifo_clear(pipe, fifo);
  
  	usbhsf_fifo_unselect(pipe, fifo);
  
  	usbhsf_rx_irq_ctrl(pipe, 1);
  	usbhs_pipe_enable(pipe);
  
  	return ret;
  
  }
  
  static int usbhs_dcp_dir_switch_done(struct usbhs_pkt *pkt, int *is_done)
  {
  	struct usbhs_pipe *pipe = pkt->pipe;
  
  	if (pkt->handler == &usbhs_dcp_status_stage_in_handler)
  		usbhsf_tx_irq_ctrl(pipe, 0);
  	else
  		usbhsf_rx_irq_ctrl(pipe, 0);
  
  	pkt->actual = pkt->length;
  	*is_done = 1;
  
  	return 0;
  }
  
  struct usbhs_pkt_handle usbhs_dcp_status_stage_in_handler = {
  	.prepare = usbhs_dcp_dir_switch_to_write,
  	.try_run = usbhs_dcp_dir_switch_done,
  };
  
  struct usbhs_pkt_handle usbhs_dcp_status_stage_out_handler = {
  	.prepare = usbhs_dcp_dir_switch_to_read,
  	.try_run = usbhs_dcp_dir_switch_done,
  };
  
  /*
   *		DCP data stage (push)
   */
  static int usbhsf_dcp_data_stage_try_push(struct usbhs_pkt *pkt, int *is_done)
  {
  	struct usbhs_pipe *pipe = pkt->pipe;
  
  	usbhs_pipe_sequence_data1(pipe); /* DATA1 */
  
  	/*
  	 * change handler to PIO push
  	 */
  	pkt->handler = &usbhs_fifo_pio_push_handler;
  
  	return pkt->handler->prepare(pkt, is_done);
  }
  
  struct usbhs_pkt_handle usbhs_dcp_data_stage_out_handler = {
  	.prepare = usbhsf_dcp_data_stage_try_push,
  };
  
  /*
   *		DCP data stage (pop)
   */
  static int usbhsf_dcp_data_stage_prepare_pop(struct usbhs_pkt *pkt,
  					     int *is_done)
  {
  	struct usbhs_pipe *pipe = pkt->pipe;
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct usbhs_fifo *fifo = usbhsf_get_cfifo(priv);
  
  	if (usbhs_pipe_is_busy(pipe))
  		return 0;
  
  	/*
  	 * prepare pop for DCP should
  	 *  - change DCP direction,
  	 *  - clear fifo
  	 *  - DATA1
  	 */
  	usbhs_pipe_disable(pipe);
  
  	usbhs_pipe_sequence_data1(pipe); /* DATA1 */
  
  	usbhsf_fifo_select(pipe, fifo, 0);
  	usbhsf_fifo_clear(pipe, fifo);
  	usbhsf_fifo_unselect(pipe, fifo);
  
  	/*
  	 * change handler to PIO pop
  	 */
  	pkt->handler = &usbhs_fifo_pio_pop_handler;
  
  	return pkt->handler->prepare(pkt, is_done);
  }
  
  struct usbhs_pkt_handle usbhs_dcp_data_stage_in_handler = {
  	.prepare = usbhsf_dcp_data_stage_prepare_pop,
  };
  
  /*
   *		PIO push handler
   */
  static int usbhsf_pio_try_push(struct usbhs_pkt *pkt, int *is_done)
  {
  	struct usbhs_pipe *pipe = pkt->pipe;
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct device *dev = usbhs_priv_to_dev(priv);
  	struct usbhs_fifo *fifo = usbhsf_get_cfifo(priv); /* CFIFO */
  	void __iomem *addr = priv->base + fifo->port;
  	u8 *buf;
  	int maxp = usbhs_pipe_get_maxpacket(pipe);
  	int total_len;
  	int i, ret, len;
  	int is_short;
  
  	usbhs_pipe_data_sequence(pipe, pkt->sequence);
  	pkt->sequence = -1; /* -1 sequence will be ignored */
  
  	usbhs_pipe_set_trans_count_if_bulk(pipe, pkt->length);
  
  	ret = usbhsf_fifo_select(pipe, fifo, 1);
  	if (ret < 0)
  		return 0;
  
  	ret = usbhs_pipe_is_accessible(pipe);
  	if (ret < 0) {
  		/* inaccessible pipe is not an error */
  		ret = 0;
  		goto usbhs_fifo_write_busy;
  	}
  
  	ret = usbhsf_fifo_barrier(priv, fifo);
  	if (ret < 0)
  		goto usbhs_fifo_write_busy;
  
  	buf		= pkt->buf    + pkt->actual;
  	len		= pkt->length - pkt->actual;
  	len		= min(len, maxp);
  	total_len	= len;
  	is_short	= total_len < maxp;
  
  	/*
  	 * FIXME
  	 *
  	 * 32-bit access only
  	 */
  	if (len >= 4 && !((unsigned long)buf & 0x03)) {
  		iowrite32_rep(addr, buf, len / 4);
  		len %= 4;
  		buf += total_len - len;
  	}
  
  	/* the rest operation */
  	for (i = 0; i < len; i++)
  		iowrite8(buf[i], addr + (0x03 - (i & 0x03)));
  
  	/*
  	 * variable update
  	 */
  	pkt->actual += total_len;
  
  	if (pkt->actual < pkt->length)
  		*is_done = 0;		/* there are remainder data */
  	else if (is_short)
  		*is_done = 1;		/* short packet */
  	else
  		*is_done = !pkt->zero;	/* send zero packet ? */
  
  	/*
  	 * pipe/irq handling
  	 */
  	if (is_short)
  		usbhsf_send_terminator(pipe, fifo);
  
  	usbhsf_tx_irq_ctrl(pipe, !*is_done);
  	usbhs_pipe_running(pipe, !*is_done);
  	usbhs_pipe_enable(pipe);
  
  	dev_dbg(dev, "  send %d (%d/ %d/ %d/ %d)\n",
  		usbhs_pipe_number(pipe),
  		pkt->length, pkt->actual, *is_done, pkt->zero);
  
  	/*
  	 * Transmission end
  	 */
  	if (*is_done) {
  		if (usbhs_pipe_is_dcp(pipe))
  			usbhs_dcp_control_transfer_done(pipe);
  	}
  
  	usbhsf_fifo_unselect(pipe, fifo);
  
  	return 0;
  
  usbhs_fifo_write_busy:
  	usbhsf_fifo_unselect(pipe, fifo);
  
  	/*
  	 * pipe is busy.
  	 * retry in interrupt
  	 */
  	usbhsf_tx_irq_ctrl(pipe, 1);
  	usbhs_pipe_running(pipe, 1);
  
  	return ret;
  }
  
  static int usbhsf_pio_prepare_push(struct usbhs_pkt *pkt, int *is_done)
  {
  	if (usbhs_pipe_is_running(pkt->pipe))
  		return 0;
  
  	return usbhsf_pio_try_push(pkt, is_done);
  }
  
  struct usbhs_pkt_handle usbhs_fifo_pio_push_handler = {
  	.prepare = usbhsf_pio_prepare_push,
  	.try_run = usbhsf_pio_try_push,
  };
  
  /*
   *		PIO pop handler
   */
  static int usbhsf_prepare_pop(struct usbhs_pkt *pkt, int *is_done)
  {
  	struct usbhs_pipe *pipe = pkt->pipe;
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct usbhs_fifo *fifo = usbhsf_get_cfifo(priv);
  
  	if (usbhs_pipe_is_busy(pipe))
  		return 0;
  
  	if (usbhs_pipe_is_running(pipe))
  		return 0;
  
  	/*
  	 * pipe enable to prepare packet receive
  	 */
  	usbhs_pipe_data_sequence(pipe, pkt->sequence);
  	pkt->sequence = -1; /* -1 sequence will be ignored */
  
  	if (usbhs_pipe_is_dcp(pipe))
  		usbhsf_fifo_clear(pipe, fifo);
  
  	usbhs_pipe_set_trans_count_if_bulk(pipe, pkt->length);
  	usbhs_pipe_enable(pipe);
  	usbhs_pipe_running(pipe, 1);
  	usbhsf_rx_irq_ctrl(pipe, 1);
  
  	return 0;
  }
  
  static int usbhsf_pio_try_pop(struct usbhs_pkt *pkt, int *is_done)
  {
  	struct usbhs_pipe *pipe = pkt->pipe;
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct device *dev = usbhs_priv_to_dev(priv);
  	struct usbhs_fifo *fifo = usbhsf_get_cfifo(priv); /* CFIFO */
  	void __iomem *addr = priv->base + fifo->port;
  	u8 *buf;
  	u32 data = 0;
  	int maxp = usbhs_pipe_get_maxpacket(pipe);
  	int rcv_len, len;
  	int i, ret;
  	int total_len = 0;
  
  	ret = usbhsf_fifo_select(pipe, fifo, 0);
  	if (ret < 0)
  		return 0;
  
  	ret = usbhsf_fifo_barrier(priv, fifo);
  	if (ret < 0)
  		goto usbhs_fifo_read_busy;
  
  	rcv_len = usbhsf_fifo_rcv_len(priv, fifo);
  
  	buf		= pkt->buf    + pkt->actual;
  	len		= pkt->length - pkt->actual;
  	len		= min(len, rcv_len);
  	total_len	= len;
  
  	/*
  	 * update actual length first here to decide disable pipe.
  	 * if this pipe keeps BUF status and all data were popped,
  	 * then, next interrupt/token will be issued again
  	 */
  	pkt->actual += total_len;
  
  	if ((pkt->actual == pkt->length) ||	/* receive all data */
  	    (total_len < maxp)) {		/* short packet */
  		*is_done = 1;
  		usbhsf_rx_irq_ctrl(pipe, 0);
  		usbhs_pipe_running(pipe, 0);
  		/*
  		 * If function mode, since this controller is possible to enter
  		 * Control Write status stage at this timing, this driver
  		 * should not disable the pipe. If such a case happens, this
  		 * controller is not able to complete the status stage.
  		 */
  		if (!usbhs_mod_is_host(priv) && !usbhs_pipe_is_dcp(pipe))
  			usbhs_pipe_disable(pipe);	/* disable pipe first */
  	}
  
  	/*
  	 * Buffer clear if Zero-Length packet
  	 *
  	 * see
  	 * "Operation" - "FIFO Buffer Memory" - "FIFO Port Function"
  	 */
  	if (0 == rcv_len) {
  		pkt->zero = 1;
  		usbhsf_fifo_clear(pipe, fifo);
  		goto usbhs_fifo_read_end;
  	}
  
  	/*
  	 * FIXME
  	 *
  	 * 32-bit access only
  	 */
  	if (len >= 4 && !((unsigned long)buf & 0x03)) {
  		ioread32_rep(addr, buf, len / 4);
  		len %= 4;
  		buf += total_len - len;
  	}
  
  	/* the rest operation */
  	for (i = 0; i < len; i++) {
  		if (!(i & 0x03))
  			data = ioread32(addr);
  
  		buf[i] = (data >> ((i & 0x03) * 8)) & 0xff;
  	}
  
  usbhs_fifo_read_end:
  	dev_dbg(dev, "  recv %d (%d/ %d/ %d/ %d)\n",
  		usbhs_pipe_number(pipe),
  		pkt->length, pkt->actual, *is_done, pkt->zero);
  
  	/*
  	 * Transmission end
  	 */
  	if (*is_done) {
  		if (usbhs_pipe_is_dcp(pipe))
  			usbhs_dcp_control_transfer_done(pipe);
  	}
  
  usbhs_fifo_read_busy:
  	usbhsf_fifo_unselect(pipe, fifo);
  
  	return ret;
  }
  
  struct usbhs_pkt_handle usbhs_fifo_pio_pop_handler = {
  	.prepare = usbhsf_prepare_pop,
  	.try_run = usbhsf_pio_try_pop,
  };
  
  /*
   *		DCP ctrol statge handler
   */
  static int usbhsf_ctrl_stage_end(struct usbhs_pkt *pkt, int *is_done)
  {
  	usbhs_dcp_control_transfer_done(pkt->pipe);
  
  	*is_done = 1;
  
  	return 0;
  }
  
  struct usbhs_pkt_handle usbhs_ctrl_stage_end_handler = {
  	.prepare = usbhsf_ctrl_stage_end,
  	.try_run = usbhsf_ctrl_stage_end,
  };
  
  /*
   *		DMA fifo functions
   */
  static struct dma_chan *usbhsf_dma_chan_get(struct usbhs_fifo *fifo,
  					    struct usbhs_pkt *pkt)
  {
  	if (&usbhs_fifo_dma_push_handler == pkt->handler)
  		return fifo->tx_chan;
  
  	if (&usbhs_fifo_dma_pop_handler == pkt->handler)
  		return fifo->rx_chan;
  
  	return NULL;
  }
  
  static struct usbhs_fifo *usbhsf_get_dma_fifo(struct usbhs_priv *priv,
  					      struct usbhs_pkt *pkt)
  {
  	struct usbhs_fifo *fifo;
  
  	/* DMA :: D0FIFO */
  	fifo = usbhsf_get_d0fifo(priv);
  	if (usbhsf_dma_chan_get(fifo, pkt) &&
  	    !usbhsf_fifo_is_busy(fifo))
  		return fifo;
  
  	/* DMA :: D1FIFO */
  	fifo = usbhsf_get_d1fifo(priv);
  	if (usbhsf_dma_chan_get(fifo, pkt) &&
  	    !usbhsf_fifo_is_busy(fifo))
  		return fifo;
  
  	return NULL;
  }
  
  #define usbhsf_dma_start(p, f)	__usbhsf_dma_ctrl(p, f, DREQE)
  #define usbhsf_dma_stop(p, f)	__usbhsf_dma_ctrl(p, f, 0)
  static void __usbhsf_dma_ctrl(struct usbhs_pipe *pipe,
  			      struct usbhs_fifo *fifo,
  			      u16 dreqe)
  {
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  
  	usbhs_bset(priv, fifo->sel, DREQE, dreqe);
  }
  
  static int __usbhsf_dma_map_ctrl(struct usbhs_pkt *pkt, int map)
  {
  	struct usbhs_pipe *pipe = pkt->pipe;
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct usbhs_pipe_info *info = usbhs_priv_to_pipeinfo(priv);
  
  	return info->dma_map_ctrl(pkt, map);
  }
  
  static void usbhsf_dma_complete(void *arg);
  static void xfer_work(struct work_struct *work)
  {
  	struct usbhs_pkt *pkt = container_of(work, struct usbhs_pkt, work);
  	struct usbhs_pipe *pipe = pkt->pipe;
  	struct usbhs_fifo *fifo;
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct dma_async_tx_descriptor *desc;
  	struct dma_chan *chan;
  	struct device *dev = usbhs_priv_to_dev(priv);
  	enum dma_transfer_direction dir;
  	unsigned long flags;
  
  	usbhs_lock(priv, flags);
  	fifo = usbhs_pipe_to_fifo(pipe);
  	if (!fifo)
  		goto xfer_work_end;
  
  	chan = usbhsf_dma_chan_get(fifo, pkt);
  	dir = usbhs_pipe_is_dir_in(pipe) ? DMA_DEV_TO_MEM : DMA_MEM_TO_DEV;
  
  	desc = dmaengine_prep_slave_single(chan, pkt->dma + pkt->actual,
  					pkt->trans, dir,
  					DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
  	if (!desc)
  		goto xfer_work_end;
  
  	desc->callback		= usbhsf_dma_complete;
  	desc->callback_param	= pipe;
  
  	if (dmaengine_submit(desc) < 0) {
  		dev_err(dev, "Failed to submit dma descriptor\n");
  		goto xfer_work_end;
  	}
  
  	dev_dbg(dev, "  %s %d (%d/ %d)\n",
  		fifo->name, usbhs_pipe_number(pipe), pkt->length, pkt->zero);
  
  	usbhs_pipe_running(pipe, 1);
  	usbhs_pipe_set_trans_count_if_bulk(pipe, pkt->trans);
  	dma_async_issue_pending(chan);
  	usbhsf_dma_start(pipe, fifo);
  	usbhs_pipe_enable(pipe);
  
  xfer_work_end:
  	usbhs_unlock(priv, flags);
  }
  
  /*
   *		DMA push handler
   */
  static int usbhsf_dma_prepare_push(struct usbhs_pkt *pkt, int *is_done)
  {
  	struct usbhs_pipe *pipe = pkt->pipe;
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct usbhs_fifo *fifo;
  	int len = pkt->length - pkt->actual;
  	int ret;
  
  	if (usbhs_pipe_is_busy(pipe))
  		return 0;
  
  	/* use PIO if packet is less than pio_dma_border or pipe is DCP */
  	if ((len < usbhs_get_dparam(priv, pio_dma_border)) ||
  	    usbhs_pipe_is_dcp(pipe))
  		goto usbhsf_pio_prepare_push;
  
  	if (len & 0x7) /* 8byte alignment */
  		goto usbhsf_pio_prepare_push;
  
  	if ((uintptr_t)(pkt->buf + pkt->actual) & 0x7) /* 8byte alignment */
  		goto usbhsf_pio_prepare_push;
  
  	/* return at this time if the pipe is running */
  	if (usbhs_pipe_is_running(pipe))
  		return 0;
  
  	/* get enable DMA fifo */
  	fifo = usbhsf_get_dma_fifo(priv, pkt);
  	if (!fifo)
  		goto usbhsf_pio_prepare_push;
  
  	if (usbhsf_dma_map(pkt) < 0)
  		goto usbhsf_pio_prepare_push;
  
  	ret = usbhsf_fifo_select(pipe, fifo, 0);
  	if (ret < 0)
  		goto usbhsf_pio_prepare_push_unmap;
  
  	pkt->trans = len;
  
  	usbhsf_tx_irq_ctrl(pipe, 0);
  	INIT_WORK(&pkt->work, xfer_work);
  	schedule_work(&pkt->work);
  
  	return 0;
  
  usbhsf_pio_prepare_push_unmap:
  	usbhsf_dma_unmap(pkt);
  usbhsf_pio_prepare_push:
  	/*
  	 * change handler to PIO
  	 */
  	pkt->handler = &usbhs_fifo_pio_push_handler;
  
  	return pkt->handler->prepare(pkt, is_done);
  }
  
  static int usbhsf_dma_push_done(struct usbhs_pkt *pkt, int *is_done)
  {
  	struct usbhs_pipe *pipe = pkt->pipe;
  	int is_short = pkt->trans % usbhs_pipe_get_maxpacket(pipe);
  
  	pkt->actual += pkt->trans;
  
  	if (pkt->actual < pkt->length)
  		*is_done = 0;		/* there are remainder data */
  	else if (is_short)
  		*is_done = 1;		/* short packet */
  	else
  		*is_done = !pkt->zero;	/* send zero packet? */
  
  	usbhs_pipe_running(pipe, !*is_done);
  
  	usbhsf_dma_stop(pipe, pipe->fifo);
  	usbhsf_dma_unmap(pkt);
  	usbhsf_fifo_unselect(pipe, pipe->fifo);
  
  	if (!*is_done) {
  		/* change handler to PIO */
  		pkt->handler = &usbhs_fifo_pio_push_handler;
  		return pkt->handler->try_run(pkt, is_done);
  	}
  
  	return 0;
  }
  
  struct usbhs_pkt_handle usbhs_fifo_dma_push_handler = {
  	.prepare	= usbhsf_dma_prepare_push,
  	.dma_done	= usbhsf_dma_push_done,
  };
  
  /*
   *		DMA pop handler
   */
  static int usbhsf_dma_try_pop(struct usbhs_pkt *pkt, int *is_done)
  {
  	struct usbhs_pipe *pipe = pkt->pipe;
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct usbhs_fifo *fifo;
  	int len, ret;
  
  	if (usbhs_pipe_is_busy(pipe))
  		return 0;
  
  	if (usbhs_pipe_is_dcp(pipe))
  		goto usbhsf_pio_prepare_pop;
  
  	/* get enable DMA fifo */
  	fifo = usbhsf_get_dma_fifo(priv, pkt);
  	if (!fifo)
  		goto usbhsf_pio_prepare_pop;
  
  	if ((uintptr_t)(pkt->buf + pkt->actual) & 0x7) /* 8byte alignment */
  		goto usbhsf_pio_prepare_pop;
  
  	ret = usbhsf_fifo_select(pipe, fifo, 0);
  	if (ret < 0)
  		goto usbhsf_pio_prepare_pop;
  
  	/* use PIO if packet is less than pio_dma_border */
  	len = usbhsf_fifo_rcv_len(priv, fifo);
  	len = min(pkt->length - pkt->actual, len);
  	if (len & 0x7) /* 8byte alignment */
  		goto usbhsf_pio_prepare_pop_unselect;
  
  	if (len < usbhs_get_dparam(priv, pio_dma_border))
  		goto usbhsf_pio_prepare_pop_unselect;
  
  	ret = usbhsf_fifo_barrier(priv, fifo);
  	if (ret < 0)
  		goto usbhsf_pio_prepare_pop_unselect;
  
  	if (usbhsf_dma_map(pkt) < 0)
  		goto usbhsf_pio_prepare_pop_unselect;
  
  	/* DMA */
  
  	/*
  	 * usbhs_fifo_dma_pop_handler :: prepare
  	 * enabled irq to come here.
  	 * but it is no longer needed for DMA. disable it.
  	 */
  	usbhsf_rx_irq_ctrl(pipe, 0);
  
  	pkt->trans = len;
  
  	INIT_WORK(&pkt->work, xfer_work);
  	schedule_work(&pkt->work);
  
  	return 0;
  
  usbhsf_pio_prepare_pop_unselect:
  	usbhsf_fifo_unselect(pipe, fifo);
  usbhsf_pio_prepare_pop:
  
  	/*
  	 * change handler to PIO
  	 */
  	pkt->handler = &usbhs_fifo_pio_pop_handler;
  
  	return pkt->handler->try_run(pkt, is_done);
  }
  
  static int usbhsf_dma_pop_done(struct usbhs_pkt *pkt, int *is_done)
  {
  	struct usbhs_pipe *pipe = pkt->pipe;
  	int maxp = usbhs_pipe_get_maxpacket(pipe);
  
  	usbhsf_dma_stop(pipe, pipe->fifo);
  	usbhsf_dma_unmap(pkt);
  	usbhsf_fifo_unselect(pipe, pipe->fifo);
  
  	pkt->actual += pkt->trans;
  
  	if ((pkt->actual == pkt->length) ||	/* receive all data */
  	    (pkt->trans < maxp)) {		/* short packet */
  		*is_done = 1;
  		usbhs_pipe_running(pipe, 0);
  	} else {
  		/* re-enable */
  		usbhs_pipe_running(pipe, 0);
  		usbhsf_prepare_pop(pkt, is_done);
  	}
  
  	return 0;
  }
  
  struct usbhs_pkt_handle usbhs_fifo_dma_pop_handler = {
  	.prepare	= usbhsf_prepare_pop,
  	.try_run	= usbhsf_dma_try_pop,
  	.dma_done	= usbhsf_dma_pop_done
  };
  
  /*
   *		DMA setting
   */
  static bool usbhsf_dma_filter(struct dma_chan *chan, void *param)
  {
  	struct sh_dmae_slave *slave = param;
  
  	/*
  	 * FIXME
  	 *
  	 * usbhs doesn't recognize id = 0 as valid DMA
  	 */
  	if (0 == slave->shdma_slave.slave_id)
  		return false;
  
  	chan->private = slave;
  
  	return true;
  }
  
  static void usbhsf_dma_quit(struct usbhs_priv *priv, struct usbhs_fifo *fifo)
  {
  	if (fifo->tx_chan)
  		dma_release_channel(fifo->tx_chan);
  	if (fifo->rx_chan)
  		dma_release_channel(fifo->rx_chan);
  
  	fifo->tx_chan = NULL;
  	fifo->rx_chan = NULL;
  }
  
  static void usbhsf_dma_init(struct usbhs_priv *priv,
  			    struct usbhs_fifo *fifo)
  {
  	struct device *dev = usbhs_priv_to_dev(priv);
  	dma_cap_mask_t mask;
  
  	dma_cap_zero(mask);
  	dma_cap_set(DMA_SLAVE, mask);
  	fifo->tx_chan = dma_request_channel(mask, usbhsf_dma_filter,
  					    &fifo->tx_slave);
  
  	dma_cap_zero(mask);
  	dma_cap_set(DMA_SLAVE, mask);
  	fifo->rx_chan = dma_request_channel(mask, usbhsf_dma_filter,
  					    &fifo->rx_slave);
  
  	if (fifo->tx_chan || fifo->rx_chan)
  		dev_dbg(dev, "enable DMAEngine (%s%s%s)\n",
  			 fifo->name,
  			 fifo->tx_chan ? "[TX]" : "    ",
  			 fifo->rx_chan ? "[RX]" : "    ");
  }
  
  /*
   *		irq functions
   */
  static int usbhsf_irq_empty(struct usbhs_priv *priv,
  			    struct usbhs_irq_state *irq_state)
  {
  	struct usbhs_pipe *pipe;
  	struct device *dev = usbhs_priv_to_dev(priv);
  	int i, ret;
  
  	if (!irq_state->bempsts) {
  		dev_err(dev, "debug %s !!\n", __func__);
  		return -EIO;
  	}
  
  	dev_dbg(dev, "irq empty [0x%04x]\n", irq_state->bempsts);
  
  	/*
  	 * search interrupted "pipe"
  	 * not "uep".
  	 */
  	usbhs_for_each_pipe_with_dcp(pipe, priv, i) {
  		if (!(irq_state->bempsts & (1 << i)))
  			continue;
  
  		ret = usbhsf_pkt_handler(pipe, USBHSF_PKT_TRY_RUN);
  		if (ret < 0)
  			dev_err(dev, "irq_empty run_error %d : %d\n", i, ret);
  	}
  
  	return 0;
  }
  
  static int usbhsf_irq_ready(struct usbhs_priv *priv,
  			    struct usbhs_irq_state *irq_state)
  {
  	struct usbhs_pipe *pipe;
  	struct device *dev = usbhs_priv_to_dev(priv);
  	int i, ret;
  
  	if (!irq_state->brdysts) {
  		dev_err(dev, "debug %s !!\n", __func__);
  		return -EIO;
  	}
  
  	dev_dbg(dev, "irq ready [0x%04x]\n", irq_state->brdysts);
  
  	/*
  	 * search interrupted "pipe"
  	 * not "uep".
  	 */
  	usbhs_for_each_pipe_with_dcp(pipe, priv, i) {
  		if (!(irq_state->brdysts & (1 << i)))
  			continue;
  
  		ret = usbhsf_pkt_handler(pipe, USBHSF_PKT_TRY_RUN);
  		if (ret < 0)
  			dev_err(dev, "irq_ready run_error %d : %d\n", i, ret);
  	}
  
  	return 0;
  }
  
  static void usbhsf_dma_complete(void *arg)
  {
  	struct usbhs_pipe *pipe = arg;
  	struct usbhs_priv *priv = usbhs_pipe_to_priv(pipe);
  	struct device *dev = usbhs_priv_to_dev(priv);
  	int ret;
  
  	ret = usbhsf_pkt_handler(pipe, USBHSF_PKT_DMA_DONE);
  	if (ret < 0)
  		dev_err(dev, "dma_complete run_error %d : %d\n",
  			usbhs_pipe_number(pipe), ret);
  }
  
  /*
   *		fifo init
   */
  void usbhs_fifo_init(struct usbhs_priv *priv)
  {
  	struct usbhs_mod *mod = usbhs_mod_get_current(priv);
  	struct usbhs_fifo *cfifo = usbhsf_get_cfifo(priv);
  	struct usbhs_fifo *d0fifo = usbhsf_get_d0fifo(priv);
  	struct usbhs_fifo *d1fifo = usbhsf_get_d1fifo(priv);
  
  	mod->irq_empty		= usbhsf_irq_empty;
  	mod->irq_ready		= usbhsf_irq_ready;
  	mod->irq_bempsts	= 0;
  	mod->irq_brdysts	= 0;
  
  	cfifo->pipe	= NULL;
  	d0fifo->pipe	= NULL;
  	d1fifo->pipe	= NULL;
  }
  
  void usbhs_fifo_quit(struct usbhs_priv *priv)
  {
  	struct usbhs_mod *mod = usbhs_mod_get_current(priv);
  
  	mod->irq_empty		= NULL;
  	mod->irq_ready		= NULL;
  	mod->irq_bempsts	= 0;
  	mod->irq_brdysts	= 0;
  }
  
  int usbhs_fifo_probe(struct usbhs_priv *priv)
  {
  	struct usbhs_fifo *fifo;
  
  	/* CFIFO */
  	fifo = usbhsf_get_cfifo(priv);
  	fifo->name	= "CFIFO";
  	fifo->port	= CFIFO;
  	fifo->sel	= CFIFOSEL;
  	fifo->ctr	= CFIFOCTR;
  
  	/* D0FIFO */
  	fifo = usbhsf_get_d0fifo(priv);
  	fifo->name	= "D0FIFO";
  	fifo->port	= D0FIFO;
  	fifo->sel	= D0FIFOSEL;
  	fifo->ctr	= D0FIFOCTR;
  	fifo->tx_slave.shdma_slave.slave_id	= usbhs_get_dparam(priv, d0_tx_id);
  	fifo->rx_slave.shdma_slave.slave_id	= usbhs_get_dparam(priv, d0_rx_id);
  	usbhsf_dma_init(priv, fifo);
  
  	/* D1FIFO */
  	fifo = usbhsf_get_d1fifo(priv);
  	fifo->name	= "D1FIFO";
  	fifo->port	= D1FIFO;
  	fifo->sel	= D1FIFOSEL;
  	fifo->ctr	= D1FIFOCTR;
  	fifo->tx_slave.shdma_slave.slave_id	= usbhs_get_dparam(priv, d1_tx_id);
  	fifo->rx_slave.shdma_slave.slave_id	= usbhs_get_dparam(priv, d1_rx_id);
  	usbhsf_dma_init(priv, fifo);
  
  	return 0;
  }
  
  void usbhs_fifo_remove(struct usbhs_priv *priv)
  {
  	usbhsf_dma_quit(priv, usbhsf_get_d0fifo(priv));
  	usbhsf_dma_quit(priv, usbhsf_get_d1fifo(priv));
  }
  