/*
   * File:         bf5xx_sport.c
   * Based on:
   * Author:       Roy Huang <roy.huang@analog.com>
   *
   * Created:      Tue Sep 21 10:52:42 CEST 2004
   * Description:
   *               Blackfin SPORT Driver
   *
   *               Copyright 2004-2007 Analog Devices Inc.
   *
   * Bugs:         Enter bugs at http://blackfin.uclinux.org/
   *
   * 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.
   *
   * 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, see the file COPYING, or write
   * to the Free Software Foundation, Inc.,
   * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
   */
  
  #include <linux/kernel.h>
  #include <linux/slab.h>
  #include <linux/delay.h>
  #include <linux/dma-mapping.h>
  #include <linux/gpio.h>
  #include <linux/bug.h>

  #include <linux/module.h>

  #include <asm/portmux.h>
  #include <asm/dma.h>
  #include <asm/blackfin.h>
  #include <asm/cacheflush.h>
  
  #include "bf5xx-sport.h"
  /* delay between frame sync pulse and first data bit in multichannel mode */
  #define FRAME_DELAY (1<<12)

  /* note: multichannel is in units of 8 channels,
   * tdm_count is # channels NOT / 8 ! */
  int sport_set_multichannel(struct sport_device *sport,
  		int tdm_count, u32 mask, int packed)
  {
  	pr_debug("%s tdm_count=%d mask:0x%08x packed=%d
  ", __func__,
  			tdm_count, mask, packed);
  
  	if ((sport->regs->tcr1 & TSPEN) || (sport->regs->rcr1 & RSPEN))
  		return -EBUSY;
  
  	if (tdm_count & 0x7)
  		return -EINVAL;
  
  	if (tdm_count > 32)
  		return -EINVAL; /* Only support less than 32 channels now */
  
  	if (tdm_count) {
  		sport->regs->mcmc1 = ((tdm_count>>3)-1) << 12;
  		sport->regs->mcmc2 = FRAME_DELAY | MCMEN | \
  				(packed ? (MCDTXPE|MCDRXPE) : 0);
  
  		sport->regs->mtcs0 = mask;
  		sport->regs->mrcs0 = mask;
  		sport->regs->mtcs1 = 0;
  		sport->regs->mrcs1 = 0;
  		sport->regs->mtcs2 = 0;
  		sport->regs->mrcs2 = 0;
  		sport->regs->mtcs3 = 0;
  		sport->regs->mrcs3 = 0;
  	} else {
  		sport->regs->mcmc1 = 0;
  		sport->regs->mcmc2 = 0;
  
  		sport->regs->mtcs0 = 0;
  		sport->regs->mrcs0 = 0;
  	}
  
  	sport->regs->mtcs1 = 0; sport->regs->mtcs2 = 0; sport->regs->mtcs3 = 0;
  	sport->regs->mrcs1 = 0; sport->regs->mrcs2 = 0; sport->regs->mrcs3 = 0;
  
  	SSYNC();
  
  	return 0;
  }
  EXPORT_SYMBOL(sport_set_multichannel);
  
  int sport_config_rx(struct sport_device *sport, unsigned int rcr1,
  		unsigned int rcr2, unsigned int clkdiv, unsigned int fsdiv)
  {
  	if ((sport->regs->tcr1 & TSPEN) || (sport->regs->rcr1 & RSPEN))
  		return -EBUSY;
  
  	sport->regs->rcr1 = rcr1;
  	sport->regs->rcr2 = rcr2;
  	sport->regs->rclkdiv = clkdiv;
  	sport->regs->rfsdiv = fsdiv;
  
  	SSYNC();
  
  	return 0;
  }
  EXPORT_SYMBOL(sport_config_rx);
  
  int sport_config_tx(struct sport_device *sport, unsigned int tcr1,
  		unsigned int tcr2, unsigned int clkdiv, unsigned int fsdiv)
  {
  	if ((sport->regs->tcr1 & TSPEN) || (sport->regs->rcr1 & RSPEN))
  		return -EBUSY;
  
  	sport->regs->tcr1 = tcr1;
  	sport->regs->tcr2 = tcr2;
  	sport->regs->tclkdiv = clkdiv;
  	sport->regs->tfsdiv = fsdiv;
  
  	SSYNC();
  
  	return 0;
  }
  EXPORT_SYMBOL(sport_config_tx);
  
  static void setup_desc(struct dmasg *desc, void *buf, int fragcount,
  		size_t fragsize, unsigned int cfg,
  		unsigned int x_count, unsigned int ycount, size_t wdsize)
  {
  
  	int i;
  
  	for (i = 0; i < fragcount; ++i) {

  		desc[i].next_desc_addr  = &(desc[i + 1]);

  		desc[i].start_addr = (unsigned long)buf + i*fragsize;
  		desc[i].cfg = cfg;
  		desc[i].x_count = x_count;
  		desc[i].x_modify = wdsize;
  		desc[i].y_count = ycount;
  		desc[i].y_modify = wdsize;
  	}
  
  	/* make circular */

  	desc[fragcount-1].next_desc_addr = desc;

  	pr_debug("setup desc: desc0=%p, next0=%p, desc1=%p,"
  		"next1=%p
  x_count=%x,y_count=%x,addr=0x%lx,cfs=0x%x
  ",
  		desc, desc[0].next_desc_addr,
  		desc+1, desc[1].next_desc_addr,

  		desc[0].x_count, desc[0].y_count,
  		desc[0].start_addr, desc[0].cfg);
  }
  
  static int sport_start(struct sport_device *sport)
  {
  	enable_dma(sport->dma_rx_chan);
  	enable_dma(sport->dma_tx_chan);
  	sport->regs->rcr1 |= RSPEN;
  	sport->regs->tcr1 |= TSPEN;
  	SSYNC();
  
  	return 0;
  }
  
  static int sport_stop(struct sport_device *sport)
  {
  	sport->regs->tcr1 &= ~TSPEN;
  	sport->regs->rcr1 &= ~RSPEN;
  	SSYNC();
  
  	disable_dma(sport->dma_rx_chan);
  	disable_dma(sport->dma_tx_chan);
  	return 0;
  }
  
  static inline int sport_hook_rx_dummy(struct sport_device *sport)
  {
  	struct dmasg *desc, temp_desc;
  	unsigned long flags;
  
  	BUG_ON(sport->dummy_rx_desc == NULL);
  	BUG_ON(sport->curr_rx_desc == sport->dummy_rx_desc);
  
  	/* Maybe the dummy buffer descriptor ring is damaged */

  	sport->dummy_rx_desc->next_desc_addr = sport->dummy_rx_desc + 1;

  
  	local_irq_save(flags);

  	desc = get_dma_next_desc_ptr(sport->dma_rx_chan);

  	/* Copy the descriptor which will be damaged to backup */
  	temp_desc = *desc;

  	desc->x_count = sport->dummy_count / 2;

  	desc->y_count = 0;

  	desc->next_desc_addr = sport->dummy_rx_desc;

  	local_irq_restore(flags);
  	/* Waiting for dummy buffer descriptor is already hooked*/
  	while ((get_dma_curr_desc_ptr(sport->dma_rx_chan) -

  			sizeof(struct dmasg)) != sport->dummy_rx_desc)
  		continue;

  	sport->curr_rx_desc = sport->dummy_rx_desc;
  	/* Restore the damaged descriptor */
  	*desc = temp_desc;
  
  	return 0;
  }
  
  static inline int sport_rx_dma_start(struct sport_device *sport, int dummy)
  {
  	if (dummy) {

  		sport->dummy_rx_desc->next_desc_addr = sport->dummy_rx_desc;

  		sport->curr_rx_desc = sport->dummy_rx_desc;
  	} else
  		sport->curr_rx_desc = sport->dma_rx_desc;

  	set_dma_next_desc_addr(sport->dma_rx_chan, sport->curr_rx_desc);

  	set_dma_x_count(sport->dma_rx_chan, 0);
  	set_dma_x_modify(sport->dma_rx_chan, 0);
  	set_dma_config(sport->dma_rx_chan, (DMAFLOW_LARGE | NDSIZE_9 | \
  				WDSIZE_32 | WNR));
  	set_dma_curr_addr(sport->dma_rx_chan, sport->curr_rx_desc->start_addr);
  	SSYNC();
  
  	return 0;
  }
  
  static inline int sport_tx_dma_start(struct sport_device *sport, int dummy)
  {
  	if (dummy) {

  		sport->dummy_tx_desc->next_desc_addr = sport->dummy_tx_desc;

  		sport->curr_tx_desc = sport->dummy_tx_desc;
  	} else
  		sport->curr_tx_desc = sport->dma_tx_desc;

  	set_dma_next_desc_addr(sport->dma_tx_chan, sport->curr_tx_desc);

  	set_dma_x_count(sport->dma_tx_chan, 0);
  	set_dma_x_modify(sport->dma_tx_chan, 0);
  	set_dma_config(sport->dma_tx_chan,
  			(DMAFLOW_LARGE | NDSIZE_9 | WDSIZE_32));
  	set_dma_curr_addr(sport->dma_tx_chan, sport->curr_tx_desc->start_addr);
  	SSYNC();
  
  	return 0;
  }
  
  int sport_rx_start(struct sport_device *sport)
  {
  	unsigned long flags;
  	pr_debug("%s enter
  ", __func__);
  	if (sport->rx_run)
  		return -EBUSY;
  	if (sport->tx_run) {
  		/* tx is running, rx is not running */
  		BUG_ON(sport->dma_rx_desc == NULL);
  		BUG_ON(sport->curr_rx_desc != sport->dummy_rx_desc);
  		local_irq_save(flags);
  		while ((get_dma_curr_desc_ptr(sport->dma_rx_chan) -

  			sizeof(struct dmasg)) != sport->dummy_rx_desc)
  			continue;
  		sport->dummy_rx_desc->next_desc_addr = sport->dma_rx_desc;

  		local_irq_restore(flags);
  		sport->curr_rx_desc = sport->dma_rx_desc;
  	} else {
  		sport_tx_dma_start(sport, 1);
  		sport_rx_dma_start(sport, 0);
  		sport_start(sport);
  	}
  
  	sport->rx_run = 1;
  
  	return 0;
  }
  EXPORT_SYMBOL(sport_rx_start);
  
  int sport_rx_stop(struct sport_device *sport)
  {
  	pr_debug("%s enter
  ", __func__);
  
  	if (!sport->rx_run)
  		return 0;
  	if (sport->tx_run) {
  		/* TX dma is still running, hook the dummy buffer */
  		sport_hook_rx_dummy(sport);
  	} else {
  		/* Both rx and tx dma will be stopped */
  		sport_stop(sport);
  		sport->curr_rx_desc = NULL;
  		sport->curr_tx_desc = NULL;
  	}
  
  	sport->rx_run = 0;
  
  	return 0;
  }
  EXPORT_SYMBOL(sport_rx_stop);
  
  static inline int sport_hook_tx_dummy(struct sport_device *sport)
  {
  	struct dmasg *desc, temp_desc;
  	unsigned long flags;
  
  	BUG_ON(sport->dummy_tx_desc == NULL);
  	BUG_ON(sport->curr_tx_desc == sport->dummy_tx_desc);

  	sport->dummy_tx_desc->next_desc_addr = sport->dummy_tx_desc + 1;

  
  	/* Shorten the time on last normal descriptor */
  	local_irq_save(flags);

  	desc = get_dma_next_desc_ptr(sport->dma_tx_chan);

  	/* Store the descriptor which will be damaged */
  	temp_desc = *desc;

  	desc->x_count = sport->dummy_count / 2;

  	desc->y_count = 0;

  	desc->next_desc_addr = sport->dummy_tx_desc;

  	local_irq_restore(flags);
  	/* Waiting for dummy buffer descriptor is already hooked*/
  	while ((get_dma_curr_desc_ptr(sport->dma_tx_chan) - \

  			sizeof(struct dmasg)) != sport->dummy_tx_desc)
  		continue;

  	sport->curr_tx_desc = sport->dummy_tx_desc;
  	/* Restore the damaged descriptor */
  	*desc = temp_desc;
  
  	return 0;
  }
  
  int sport_tx_start(struct sport_device *sport)
  {

  	unsigned long flags;

  	pr_debug("%s: tx_run:%d, rx_run:%d
  ", __func__,
  			sport->tx_run, sport->rx_run);
  	if (sport->tx_run)
  		return -EBUSY;
  	if (sport->rx_run) {
  		BUG_ON(sport->dma_tx_desc == NULL);
  		BUG_ON(sport->curr_tx_desc != sport->dummy_tx_desc);
  		/* Hook the normal buffer descriptor */
  		local_irq_save(flags);
  		while ((get_dma_curr_desc_ptr(sport->dma_tx_chan) -

  			sizeof(struct dmasg)) != sport->dummy_tx_desc)
  			continue;
  		sport->dummy_tx_desc->next_desc_addr = sport->dma_tx_desc;

  		local_irq_restore(flags);
  		sport->curr_tx_desc = sport->dma_tx_desc;
  	} else {
  
  		sport_tx_dma_start(sport, 0);
  		/* Let rx dma run the dummy buffer */
  		sport_rx_dma_start(sport, 1);
  		sport_start(sport);
  	}
  	sport->tx_run = 1;
  	return 0;
  }
  EXPORT_SYMBOL(sport_tx_start);
  
  int sport_tx_stop(struct sport_device *sport)
  {
  	if (!sport->tx_run)
  		return 0;
  	if (sport->rx_run) {
  		/* RX is still running, hook the dummy buffer */
  		sport_hook_tx_dummy(sport);
  	} else {
  		/* Both rx and tx dma stopped */
  		sport_stop(sport);
  		sport->curr_rx_desc = NULL;
  		sport->curr_tx_desc = NULL;
  	}
  
  	sport->tx_run = 0;
  
  	return 0;
  }
  EXPORT_SYMBOL(sport_tx_stop);
  
  static inline int compute_wdsize(size_t wdsize)
  {
  	switch (wdsize) {
  	case 1:
  		return WDSIZE_8;
  	case 2:
  		return WDSIZE_16;
  	case 4:
  	default:
  		return WDSIZE_32;
  	}
  }
  
  int sport_config_rx_dma(struct sport_device *sport, void *buf,
  		int fragcount, size_t fragsize)
  {
  	unsigned int x_count;
  	unsigned int y_count;
  	unsigned int cfg;
  	dma_addr_t addr;
  
  	pr_debug("%s buf:%p, frag:%d, fragsize:0x%lx
  ", __func__, \
  			buf, fragcount, fragsize);
  
  	x_count = fragsize / sport->wdsize;
  	y_count = 0;
  
  	/* for fragments larger than 64k words we use 2d dma,
  	 * denote fragecount as two numbers' mutliply and both of them
  	 * are less than 64k.*/
  	if (x_count >= 0x10000) {
  		int i, count = x_count;
  
  		for (i = 16; i > 0; i--) {
  			x_count = 1 << i;
  			if ((count & (x_count - 1)) == 0) {
  				y_count = count >> i;
  				if (y_count < 0x10000)
  					break;
  			}
  		}
  		if (i == 0)
  			return -EINVAL;
  	}
  	pr_debug("%s(x_count:0x%x, y_count:0x%x)
  ", __func__,
  			x_count, y_count);
  
  	if (sport->dma_rx_desc)
  		dma_free_coherent(NULL, sport->rx_desc_bytes,
  					sport->dma_rx_desc, 0);
  
  	/* Allocate a new descritor ring as current one. */
  	sport->dma_rx_desc = dma_alloc_coherent(NULL, \
  			fragcount * sizeof(struct dmasg), &addr, 0);
  	sport->rx_desc_bytes = fragcount * sizeof(struct dmasg);
  
  	if (!sport->dma_rx_desc) {
  		pr_err("Failed to allocate memory for rx desc
  ");
  		return -ENOMEM;
  	}
  
  	sport->rx_buf = buf;
  	sport->rx_fragsize = fragsize;
  	sport->rx_frags = fragcount;
  
  	cfg     = 0x7000 | DI_EN | compute_wdsize(sport->wdsize) | WNR | \
  		  (DESC_ELEMENT_COUNT << 8); /* large descriptor mode */
  
  	if (y_count != 0)
  		cfg |= DMA2D;
  
  	setup_desc(sport->dma_rx_desc, buf, fragcount, fragsize,
  			cfg|DMAEN, x_count, y_count, sport->wdsize);
  
  	return 0;
  }
  EXPORT_SYMBOL(sport_config_rx_dma);
  
  int sport_config_tx_dma(struct sport_device *sport, void *buf, \
  		int fragcount, size_t fragsize)
  {
  	unsigned int x_count;
  	unsigned int y_count;
  	unsigned int cfg;
  	dma_addr_t addr;
  
  	pr_debug("%s buf:%p, fragcount:%d, fragsize:0x%lx
  ",
  			__func__, buf, fragcount, fragsize);
  
  	x_count = fragsize/sport->wdsize;
  	y_count = 0;
  
  	/* for fragments larger than 64k words we use 2d dma,
  	 * denote fragecount as two numbers' mutliply and both of them
  	 * are less than 64k.*/
  	if (x_count >= 0x10000) {
  		int i, count = x_count;
  
  		for (i = 16; i > 0; i--) {
  			x_count = 1 << i;
  			if ((count & (x_count - 1)) == 0) {
  				y_count = count >> i;
  				if (y_count < 0x10000)
  					break;
  			}
  		}
  		if (i == 0)
  			return -EINVAL;
  	}
  	pr_debug("%s x_count:0x%x, y_count:0x%x
  ", __func__,
  			x_count, y_count);
  
  
  	if (sport->dma_tx_desc) {
  		dma_free_coherent(NULL, sport->tx_desc_bytes, \
  				sport->dma_tx_desc, 0);
  	}
  
  	sport->dma_tx_desc = dma_alloc_coherent(NULL, \
  			fragcount * sizeof(struct dmasg), &addr, 0);
  	sport->tx_desc_bytes = fragcount * sizeof(struct dmasg);
  	if (!sport->dma_tx_desc) {
  		pr_err("Failed to allocate memory for tx desc
  ");
  		return -ENOMEM;
  	}
  
  	sport->tx_buf = buf;
  	sport->tx_fragsize = fragsize;
  	sport->tx_frags = fragcount;
  	cfg     = 0x7000 | DI_EN | compute_wdsize(sport->wdsize) | \
  		  (DESC_ELEMENT_COUNT << 8); /* large descriptor mode */
  
  	if (y_count != 0)
  		cfg |= DMA2D;
  
  	setup_desc(sport->dma_tx_desc, buf, fragcount, fragsize,
  			cfg|DMAEN, x_count, y_count, sport->wdsize);
  
  	return 0;
  }
  EXPORT_SYMBOL(sport_config_tx_dma);
  
  /* setup dummy dma descriptor ring, which don't generate interrupts,
   * the x_modify is set to 0 */
  static int sport_config_rx_dummy(struct sport_device *sport)
  {
  	struct dmasg *desc;
  	unsigned config;
  
  	pr_debug("%s entered
  ", __func__);

  	if (L1_DATA_A_LENGTH)
  		desc = l1_data_sram_zalloc(2 * sizeof(*desc));
  	else {

  		dma_addr_t addr;
  		desc = dma_alloc_coherent(NULL, 2 * sizeof(*desc), &addr, 0);

  		memset(desc, 0, 2 * sizeof(*desc));

  	}

  	if (desc == NULL) {
  		pr_err("Failed to allocate memory for dummy rx desc
  ");
  		return -ENOMEM;
  	}

  	sport->dummy_rx_desc = desc;
  	desc->start_addr = (unsigned long)sport->dummy_buf;
  	config = DMAFLOW_LARGE | NDSIZE_9 | compute_wdsize(sport->wdsize)
  		 | WNR | DMAEN;
  	desc->cfg = config;
  	desc->x_count = sport->dummy_count/sport->wdsize;
  	desc->x_modify = sport->wdsize;
  	desc->y_count = 0;
  	desc->y_modify = 0;
  	memcpy(desc+1, desc, sizeof(*desc));

  	desc->next_desc_addr = desc + 1;
  	desc[1].next_desc_addr = desc;

  	return 0;
  }
  
  static int sport_config_tx_dummy(struct sport_device *sport)
  {
  	struct dmasg *desc;
  	unsigned int config;
  
  	pr_debug("%s entered
  ", __func__);

  	if (L1_DATA_A_LENGTH)
  		desc = l1_data_sram_zalloc(2 * sizeof(*desc));
  	else {

  		dma_addr_t addr;
  		desc = dma_alloc_coherent(NULL, 2 * sizeof(*desc), &addr, 0);

  		memset(desc, 0, 2 * sizeof(*desc));

  	}

  	if (!desc) {
  		pr_err("Failed to allocate memory for dummy tx desc
  ");
  		return -ENOMEM;
  	}

  	sport->dummy_tx_desc = desc;
  	desc->start_addr = (unsigned long)sport->dummy_buf + \
  		sport->dummy_count;
  	config = DMAFLOW_LARGE | NDSIZE_9 |
  		 compute_wdsize(sport->wdsize) | DMAEN;
  	desc->cfg = config;
  	desc->x_count = sport->dummy_count/sport->wdsize;
  	desc->x_modify = sport->wdsize;
  	desc->y_count = 0;
  	desc->y_modify = 0;
  	memcpy(desc+1, desc, sizeof(*desc));

  	desc->next_desc_addr = desc + 1;
  	desc[1].next_desc_addr = desc;

  	return 0;
  }
  
  unsigned long sport_curr_offset_rx(struct sport_device *sport)
  {
  	unsigned long curr = get_dma_curr_addr(sport->dma_rx_chan);
  
  	return (unsigned char *)curr - sport->rx_buf;
  }
  EXPORT_SYMBOL(sport_curr_offset_rx);
  
  unsigned long sport_curr_offset_tx(struct sport_device *sport)
  {
  	unsigned long curr = get_dma_curr_addr(sport->dma_tx_chan);
  
  	return (unsigned char *)curr - sport->tx_buf;
  }
  EXPORT_SYMBOL(sport_curr_offset_tx);
  
  void sport_incfrag(struct sport_device *sport, int *frag, int tx)
  {
  	++(*frag);
  	if (tx == 1 && *frag == sport->tx_frags)
  		*frag = 0;
  
  	if (tx == 0 && *frag == sport->rx_frags)
  		*frag = 0;
  }
  EXPORT_SYMBOL(sport_incfrag);
  
  void sport_decfrag(struct sport_device *sport, int *frag, int tx)
  {
  	--(*frag);
  	if (tx == 1 && *frag == 0)
  		*frag = sport->tx_frags;
  
  	if (tx == 0 && *frag == 0)
  		*frag = sport->rx_frags;
  }
  EXPORT_SYMBOL(sport_decfrag);
  
  static int sport_check_status(struct sport_device *sport,
  		unsigned int *sport_stat,
  		unsigned int *rx_stat,
  		unsigned int *tx_stat)
  {
  	int status = 0;
  
  	if (sport_stat) {
  		SSYNC();
  		status = sport->regs->stat;
  		if (status & (TOVF|TUVF|ROVF|RUVF))
  			sport->regs->stat = (status & (TOVF|TUVF|ROVF|RUVF));
  		SSYNC();
  		*sport_stat = status;
  	}
  
  	if (rx_stat) {
  		SSYNC();
  		status = get_dma_curr_irqstat(sport->dma_rx_chan);
  		if (status & (DMA_DONE|DMA_ERR))
  			clear_dma_irqstat(sport->dma_rx_chan);
  		SSYNC();
  		*rx_stat = status;
  	}
  
  	if (tx_stat) {
  		SSYNC();
  		status = get_dma_curr_irqstat(sport->dma_tx_chan);
  		if (status & (DMA_DONE|DMA_ERR))
  			clear_dma_irqstat(sport->dma_tx_chan);
  		SSYNC();
  		*tx_stat = status;
  	}
  
  	return 0;
  }
  
  int  sport_dump_stat(struct sport_device *sport, char *buf, size_t len)
  {
  	int ret;
  
  	ret = snprintf(buf, len,
  			"sts: 0x%04x
  "
  			"rx dma %d sts: 0x%04x tx dma %d sts: 0x%04x
  ",
  			sport->regs->stat,
  			sport->dma_rx_chan,
  			get_dma_curr_irqstat(sport->dma_rx_chan),
  			sport->dma_tx_chan,
  			get_dma_curr_irqstat(sport->dma_tx_chan));
  	buf += ret;
  	len -= ret;
  
  	ret += snprintf(buf, len,
  			"curr_rx_desc:0x%p, curr_tx_desc:0x%p
  "
  			"dma_rx_desc:0x%p, dma_tx_desc:0x%p
  "
  			"dummy_rx_desc:0x%p, dummy_tx_desc:0x%p
  ",
  			sport->curr_rx_desc, sport->curr_tx_desc,
  			sport->dma_rx_desc, sport->dma_tx_desc,
  			sport->dummy_rx_desc, sport->dummy_tx_desc);
  
  	return ret;
  }
  
  static irqreturn_t rx_handler(int irq, void *dev_id)
  {
  	unsigned int rx_stat;
  	struct sport_device *sport = dev_id;
  
  	pr_debug("%s enter
  ", __func__);
  	sport_check_status(sport, NULL, &rx_stat, NULL);
  	if (!(rx_stat & DMA_DONE))
  		pr_err("rx dma is already stopped
  ");
  
  	if (sport->rx_callback) {
  		sport->rx_callback(sport->rx_data);
  		return IRQ_HANDLED;
  	}
  
  	return IRQ_NONE;
  }
  
  static irqreturn_t tx_handler(int irq, void *dev_id)
  {
  	unsigned int tx_stat;
  	struct sport_device *sport = dev_id;
  	pr_debug("%s enter
  ", __func__);
  	sport_check_status(sport, NULL, NULL, &tx_stat);
  	if (!(tx_stat & DMA_DONE)) {
  		pr_err("tx dma is already stopped
  ");
  		return IRQ_HANDLED;
  	}
  	if (sport->tx_callback) {
  		sport->tx_callback(sport->tx_data);
  		return IRQ_HANDLED;
  	}
  
  	return IRQ_NONE;
  }
  
  static irqreturn_t err_handler(int irq, void *dev_id)
  {
  	unsigned int status = 0;
  	struct sport_device *sport = dev_id;
  
  	pr_debug("%s
  ", __func__);
  	if (sport_check_status(sport, &status, NULL, NULL)) {
  		pr_err("error checking status ??");
  		return IRQ_NONE;
  	}
  
  	if (status & (TOVF|TUVF|ROVF|RUVF)) {
  		pr_info("sport status error:%s%s%s%s
  ",
  				status & TOVF ? " TOVF" : "",
  				status & TUVF ? " TUVF" : "",
  				status & ROVF ? " ROVF" : "",
  				status & RUVF ? " RUVF" : "");
  		if (status & TOVF || status & TUVF) {
  			disable_dma(sport->dma_tx_chan);
  			if (sport->tx_run)
  				sport_tx_dma_start(sport, 0);
  			else
  				sport_tx_dma_start(sport, 1);
  			enable_dma(sport->dma_tx_chan);
  		} else {
  			disable_dma(sport->dma_rx_chan);
  			if (sport->rx_run)
  				sport_rx_dma_start(sport, 0);
  			else
  				sport_rx_dma_start(sport, 1);
  			enable_dma(sport->dma_rx_chan);
  		}
  	}
  	status = sport->regs->stat;
  	if (status & (TOVF|TUVF|ROVF|RUVF))
  		sport->regs->stat = (status & (TOVF|TUVF|ROVF|RUVF));
  	SSYNC();
  
  	if (sport->err_callback)
  		sport->err_callback(sport->err_data);
  
  	return IRQ_HANDLED;
  }
  
  int sport_set_rx_callback(struct sport_device *sport,
  		       void (*rx_callback)(void *), void *rx_data)
  {
  	BUG_ON(rx_callback == NULL);
  	sport->rx_callback = rx_callback;
  	sport->rx_data = rx_data;
  
  	return 0;
  }
  EXPORT_SYMBOL(sport_set_rx_callback);
  
  int sport_set_tx_callback(struct sport_device *sport,
  		void (*tx_callback)(void *), void *tx_data)
  {
  	BUG_ON(tx_callback == NULL);
  	sport->tx_callback = tx_callback;
  	sport->tx_data = tx_data;
  
  	return 0;
  }
  EXPORT_SYMBOL(sport_set_tx_callback);
  
  int sport_set_err_callback(struct sport_device *sport,
  		void (*err_callback)(void *), void *err_data)
  {
  	BUG_ON(err_callback == NULL);
  	sport->err_callback = err_callback;
  	sport->err_data = err_data;
  
  	return 0;
  }
  EXPORT_SYMBOL(sport_set_err_callback);

  static int sport_config_pdev(struct platform_device *pdev, struct sport_param *param)

  {

  	/* Extract settings from platform data */
  	struct device *dev = &pdev->dev;
  	struct bfin_snd_platform_data *pdata = dev->platform_data;
  	struct resource *res;
  
  	param->num = pdev->id;
  
  	if (!pdata) {
  		dev_err(dev, "no platform_data
  ");
  		return -ENODEV;
  	}
  	param->pin_req = pdata->pin_req;
  
  	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  	if (!res) {
  		dev_err(dev, "no MEM resource
  ");
  		return -ENODEV;
  	}
  	param->regs = (struct sport_register *)res->start;
  
  	/* first RX, then TX */
  	res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
  	if (!res) {
  		dev_err(dev, "no rx DMA resource
  ");
  		return -ENODEV;
  	}
  	param->dma_rx_chan = res->start;
  
  	res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
  	if (!res) {
  		dev_err(dev, "no tx DMA resource
  ");
  		return -ENODEV;
  	}
  	param->dma_tx_chan = res->start;
  
  	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
  	if (!res) {
  		dev_err(dev, "no irq resource
  ");
  		return -ENODEV;
  	}
  	param->err_irq = res->start;
  
  	return 0;
  }
  
  struct sport_device *sport_init(struct platform_device *pdev,
  	unsigned int wdsize, unsigned int dummy_count, size_t priv_size)
  {
  	struct device *dev = &pdev->dev;
  	struct sport_param param;

  	struct sport_device *sport;

  	int ret;
  
  	dev_dbg(dev, "%s enter
  ", __func__);
  
  	param.wdsize = wdsize;
  	param.dummy_count = dummy_count;
  	BUG_ON(param.wdsize == 0 || param.dummy_count == 0);
  
  	ret = sport_config_pdev(pdev, &param);
  	if (ret)
  		return NULL;
  
  	if (peripheral_request_list(param.pin_req, "soc-audio")) {
  		dev_err(dev, "requesting Peripherals failed
  ");

  		return NULL;
  	}

  	sport = kzalloc(sizeof(*sport), GFP_KERNEL);
  	if (!sport) {
  		dev_err(dev, "failed to allocate for sport device
  ");
  		goto __init_err0;
  	}
  
  	sport->num = param.num;
  	sport->dma_rx_chan = param.dma_rx_chan;
  	sport->dma_tx_chan = param.dma_tx_chan;
  	sport->err_irq = param.err_irq;
  	sport->regs = param.regs;
  	sport->pin_req = param.pin_req;

  
  	if (request_dma(sport->dma_rx_chan, "SPORT RX Data") == -EBUSY) {

  		dev_err(dev, "failed to request RX dma %d
  ", sport->dma_rx_chan);

  		goto __init_err1;
  	}
  	if (set_dma_callback(sport->dma_rx_chan, rx_handler, sport) != 0) {

  		dev_err(dev, "failed to request RX irq %d
  ", sport->dma_rx_chan);

  		goto __init_err2;
  	}
  
  	if (request_dma(sport->dma_tx_chan, "SPORT TX Data") == -EBUSY) {

  		dev_err(dev, "failed to request TX dma %d
  ", sport->dma_tx_chan);

  		goto __init_err2;
  	}
  
  	if (set_dma_callback(sport->dma_tx_chan, tx_handler, sport) != 0) {

  		dev_err(dev, "failed to request TX irq %d
  ", sport->dma_tx_chan);

  		goto __init_err3;
  	}
  
  	if (request_irq(sport->err_irq, err_handler, IRQF_SHARED, "SPORT err",
  			sport) < 0) {

  		dev_err(dev, "failed to request err irq %d
  ", sport->err_irq);

  		goto __init_err3;
  	}

  	dev_info(dev, "dma rx:%d tx:%d, err irq:%d, regs:%p
  ",

  			sport->dma_rx_chan, sport->dma_tx_chan,
  			sport->err_irq, sport->regs);

  	sport->wdsize = param.wdsize;
  	sport->dummy_count = param.dummy_count;
  
  	sport->private_data = kzalloc(priv_size, GFP_KERNEL);
  	if (!sport->private_data) {
  		dev_err(dev, "could not alloc priv data %zu bytes
  ", priv_size);
  		goto __init_err4;
  	}

  	if (L1_DATA_A_LENGTH)

  		sport->dummy_buf = l1_data_sram_zalloc(param.dummy_count * 2);

  	else

  		sport->dummy_buf = kzalloc(param.dummy_count * 2, GFP_KERNEL);

  	if (sport->dummy_buf == NULL) {

  		dev_err(dev, "failed to allocate dummy buffer
  ");
  		goto __error1;

  	}

  	ret = sport_config_rx_dummy(sport);
  	if (ret) {

  		dev_err(dev, "failed to config rx dummy ring
  ");
  		goto __error2;

  	}
  	ret = sport_config_tx_dummy(sport);
  	if (ret) {

  		dev_err(dev, "failed to config tx dummy ring
  ");
  		goto __error3;

  	}

  	platform_set_drvdata(pdev, sport);

  	return sport;

  __error3:
  	if (L1_DATA_A_LENGTH)
  		l1_data_sram_free(sport->dummy_rx_desc);
  	else
  		dma_free_coherent(NULL, 2*sizeof(struct dmasg),
  				sport->dummy_rx_desc, 0);
  __error2:
  	if (L1_DATA_A_LENGTH)
  		l1_data_sram_free(sport->dummy_buf);
  	else
  		kfree(sport->dummy_buf);
  __error1:
  	kfree(sport->private_data);
  __init_err4:

  	free_irq(sport->err_irq, sport);
  __init_err3:
  	free_dma(sport->dma_tx_chan);
  __init_err2:
  	free_dma(sport->dma_rx_chan);
  __init_err1:
  	kfree(sport);

  __init_err0:
  	peripheral_free_list(param.pin_req);

  	return NULL;
  }
  EXPORT_SYMBOL(sport_init);
  
  void sport_done(struct sport_device *sport)
  {
  	if (sport == NULL)
  		return;
  
  	sport_stop(sport);
  	if (sport->dma_rx_desc)
  		dma_free_coherent(NULL, sport->rx_desc_bytes,
  			sport->dma_rx_desc, 0);
  	if (sport->dma_tx_desc)
  		dma_free_coherent(NULL, sport->tx_desc_bytes,
  			sport->dma_tx_desc, 0);
  
  #if L1_DATA_A_LENGTH != 0
  	l1_data_sram_free(sport->dummy_rx_desc);
  	l1_data_sram_free(sport->dummy_tx_desc);
  	l1_data_sram_free(sport->dummy_buf);
  #else
  	dma_free_coherent(NULL, 2*sizeof(struct dmasg),
  		sport->dummy_rx_desc, 0);
  	dma_free_coherent(NULL, 2*sizeof(struct dmasg),
  		sport->dummy_tx_desc, 0);
  	kfree(sport->dummy_buf);
  #endif
  	free_dma(sport->dma_rx_chan);
  	free_dma(sport->dma_tx_chan);
  	free_irq(sport->err_irq, sport);

  	kfree(sport->private_data);
  	peripheral_free_list(sport->pin_req);

  	kfree(sport);

  }
  EXPORT_SYMBOL(sport_done);

  /*
  * It is only used to send several bytes when dma is not enabled
   * sport controller is configured but not enabled.
   * Multichannel cannot works with pio mode */
  /* Used by ac97 to write and read codec register */
  int sport_send_and_recv(struct sport_device *sport, u8 *out_data, \
  		u8 *in_data, int len)
  {
  	unsigned short dma_config;
  	unsigned short status;
  	unsigned long flags;
  	unsigned long wait = 0;
  
  	pr_debug("%s enter, out_data:%p, in_data:%p len:%d
  ", \
  			__func__, out_data, in_data, len);
  	pr_debug("tcr1:0x%04x, tcr2:0x%04x, tclkdiv:0x%04x, tfsdiv:0x%04x
  "
  			"mcmc1:0x%04x, mcmc2:0x%04x
  ",
  			sport->regs->tcr1, sport->regs->tcr2,
  			sport->regs->tclkdiv, sport->regs->tfsdiv,
  			sport->regs->mcmc1, sport->regs->mcmc2);
  	flush_dcache_range((unsigned)out_data, (unsigned)(out_data + len));
  
  	/* Enable tx dma */
  	dma_config = (RESTART | WDSIZE_16 | DI_EN);
  	set_dma_start_addr(sport->dma_tx_chan, (unsigned long)out_data);
  	set_dma_x_count(sport->dma_tx_chan, len/2);
  	set_dma_x_modify(sport->dma_tx_chan, 2);
  	set_dma_config(sport->dma_tx_chan, dma_config);
  	enable_dma(sport->dma_tx_chan);
  
  	if (in_data != NULL) {
  		invalidate_dcache_range((unsigned)in_data, \
  				(unsigned)(in_data + len));
  		/* Enable rx dma */
  		dma_config = (RESTART | WDSIZE_16 | WNR | DI_EN);
  		set_dma_start_addr(sport->dma_rx_chan, (unsigned long)in_data);
  		set_dma_x_count(sport->dma_rx_chan, len/2);
  		set_dma_x_modify(sport->dma_rx_chan, 2);
  		set_dma_config(sport->dma_rx_chan, dma_config);
  		enable_dma(sport->dma_rx_chan);
  	}
  
  	local_irq_save(flags);
  	sport->regs->tcr1 |= TSPEN;
  	sport->regs->rcr1 |= RSPEN;
  	SSYNC();
  
  	status = get_dma_curr_irqstat(sport->dma_tx_chan);
  	while (status & DMA_RUN) {
  		udelay(1);
  		status = get_dma_curr_irqstat(sport->dma_tx_chan);
  		pr_debug("DMA status:0x%04x
  ", status);
  		if (wait++ > 100)
  			goto __over;
  	}
  	status = sport->regs->stat;
  	wait = 0;
  
  	while (!(status & TXHRE)) {
  		pr_debug("sport status:0x%04x
  ", status);
  		udelay(1);
  		status = *(unsigned short *)&sport->regs->stat;
  		if (wait++ > 1000)
  			goto __over;
  	}
  	/* Wait for the last byte sent out */
  	udelay(20);
  	pr_debug("sport status:0x%04x
  ", status);
  
  __over:
  	sport->regs->tcr1 &= ~TSPEN;
  	sport->regs->rcr1 &= ~RSPEN;
  	SSYNC();
  	disable_dma(sport->dma_tx_chan);
  	/* Clear the status */
  	clear_dma_irqstat(sport->dma_tx_chan);
  	if (in_data != NULL) {
  		disable_dma(sport->dma_rx_chan);
  		clear_dma_irqstat(sport->dma_rx_chan);
  	}
  	SSYNC();
  	local_irq_restore(flags);
  
  	return 0;
  }
  EXPORT_SYMBOL(sport_send_and_recv);
  
  MODULE_AUTHOR("Roy Huang");
  MODULE_DESCRIPTION("SPORT driver for ADI Blackfin");
  MODULE_LICENSE("GPL");