bf5xx-sport.c

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/*
 * File:         bf5xx_sport.c
 * Based on:
 * Author:       Roy Huang <[email protected]>
 *
 * 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\n", __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\nx_count=%x,y_count=%x,addr=0x%lx,cfs=0x%x\n",
        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\n", __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\n", __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\n", __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\n", __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)\n", __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\n");
        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\n",
            __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\n", __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\n");
        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\n", __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\n");
        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\n", __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\n");
        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\n"
            "rx dma %d sts: 0x%04x tx dma %d sts: 0x%04x\n",
            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\n"
            "dma_rx_desc:0x%p, dma_tx_desc:0x%p\n"
            "dummy_rx_desc:0x%p, dummy_tx_desc:0x%p\n",
            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\n", __func__);
    sport_check_status(sport, NULL, &rx_stat, NULL);
    if (!(rx_stat & DMA_DONE))
        pr_err("rx dma is already stopped\n");

    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\n", __func__);
    sport_check_status(sport, NULL, NULL, &tx_stat);
    if (!(tx_stat & DMA_DONE)) {
        pr_err("tx dma is already stopped\n");
        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\n", __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\n",
                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\n");
        return -ENODEV;
    }
    param->pin_req = pdata->pin_req;

    res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    if (!res) {
        dev_err(dev, "no MEM resource\n");
        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\n");
        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\n");
        return -ENODEV;
    }
    param->dma_tx_chan = res->start;

    res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
    if (!res) {
        dev_err(dev, "no irq resource\n");
        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\n", __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\n");
        return NULL;
    }

    sport = kzalloc(sizeof(*sport), GFP_KERNEL);
    if (!sport) {
        dev_err(dev, "failed to allocate for sport device\n");
        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\n", 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\n", 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\n", 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\n", 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\n", sport->err_irq);
        goto __init_err3;
    }

    dev_info(dev, "dma rx:%d tx:%d, err irq:%d, regs:%p\n",
            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\n", 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\n");
        goto __error1;
    }

    ret = sport_config_rx_dummy(sport);
    if (ret) {
        dev_err(dev, "failed to config rx dummy ring\n");
        goto __error2;
    }
    ret = sport_config_tx_dummy(sport);
    if (ret) {
        dev_err(dev, "failed to config tx dummy ring\n");
        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\n", \
            __func__, out_data, in_data, len);
    pr_debug("tcr1:0x%04x, tcr2:0x%04x, tclkdiv:0x%04x, tfsdiv:0x%04x\n"
            "mcmc1:0x%04x, mcmc2:0x%04x\n",
            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\n", status);
        if (wait++ > 100)
            goto __over;
    }
    status = sport->regs->stat;
    wait = 0;

    while (!(status & TXHRE)) {
        pr_debug("sport status:0x%04x\n", 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\n", 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");