tools, slub: Fix off-by-one buffer corruption after readlink() call

[linux-2.6/linux-mips.git] / arch / arm / mach-davinci / dma.c

/*
 * EDMA3 support for DaVinci
 *
 * Copyright (C) 2006-2009 Texas Instruments.
 *
 * 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, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/io.h>
#include <linux/slab.h>

#include <mach/edma.h>

/* Offsets matching "struct edmacc_param" */
#define PARM_OPT                0x00
#define PARM_SRC                0x04
#define PARM_A_B_CNT            0x08
#define PARM_DST                0x0c
#define PARM_SRC_DST_BIDX       0x10
#define PARM_LINK_BCNTRLD       0x14
#define PARM_SRC_DST_CIDX       0x18
#define PARM_CCNT               0x1c

#define PARM_SIZE               0x20

/* Offsets for EDMA CC global channel registers and their shadows */
#define SH_ER           0x00    /* 64 bits */
#define SH_ECR          0x08    /* 64 bits */
#define SH_ESR          0x10    /* 64 bits */
#define SH_CER          0x18    /* 64 bits */
#define SH_EER          0x20    /* 64 bits */
#define SH_EECR         0x28    /* 64 bits */
#define SH_EESR         0x30    /* 64 bits */
#define SH_SER          0x38    /* 64 bits */
#define SH_SECR         0x40    /* 64 bits */
#define SH_IER          0x50    /* 64 bits */
#define SH_IECR         0x58    /* 64 bits */
#define SH_IESR         0x60    /* 64 bits */
#define SH_IPR          0x68    /* 64 bits */
#define SH_ICR          0x70    /* 64 bits */
#define SH_IEVAL        0x78
#define SH_QER          0x80
#define SH_QEER         0x84
#define SH_QEECR        0x88
#define SH_QEESR        0x8c
#define SH_QSER         0x90
#define SH_QSECR        0x94
#define SH_SIZE         0x200

/* Offsets for EDMA CC global registers */
#define EDMA_REV        0x0000
#define EDMA_CCCFG      0x0004
#define EDMA_QCHMAP     0x0200  /* 8 registers */
#define EDMA_DMAQNUM    0x0240  /* 8 registers (4 on OMAP-L1xx) */
#define EDMA_QDMAQNUM   0x0260
#define EDMA_QUETCMAP   0x0280
#define EDMA_QUEPRI     0x0284
#define EDMA_EMR        0x0300  /* 64 bits */
#define EDMA_EMCR       0x0308  /* 64 bits */
#define EDMA_QEMR       0x0310
#define EDMA_QEMCR      0x0314
#define EDMA_CCERR      0x0318
#define EDMA_CCERRCLR   0x031c
#define EDMA_EEVAL      0x0320
#define EDMA_DRAE       0x0340  /* 4 x 64 bits*/
#define EDMA_QRAE       0x0380  /* 4 registers */
#define EDMA_QUEEVTENTRY        0x0400  /* 2 x 16 registers */
#define EDMA_QSTAT      0x0600  /* 2 registers */
#define EDMA_QWMTHRA    0x0620
#define EDMA_QWMTHRB    0x0624
#define EDMA_CCSTAT     0x0640

#define EDMA_M          0x1000  /* global channel registers */
#define EDMA_ECR        0x1008
#define EDMA_ECRH       0x100C
#define EDMA_SHADOW0    0x2000  /* 4 regions shadowing global channels */
#define EDMA_PARM       0x4000  /* 128 param entries */

#define PARM_OFFSET(param_no)   (EDMA_PARM + ((param_no) << 5))

#define EDMA_DCHMAP     0x0100  /* 64 registers */
#define CHMAP_EXIST     BIT(24)

#define EDMA_MAX_DMACH           64
#define EDMA_MAX_PARAMENTRY     512

/*****************************************************************************/

static void __iomem *edmacc_regs_base[EDMA_MAX_CC];

static inline unsigned int edma_read(unsigned ctlr, int offset)
{
        return (unsigned int)__raw_readl(edmacc_regs_base[ctlr] + offset);
}

static inline void edma_write(unsigned ctlr, int offset, int val)
{
        __raw_writel(val, edmacc_regs_base[ctlr] + offset);
}
static inline void edma_modify(unsigned ctlr, int offset, unsigned and,
                unsigned or)
{
        unsigned val = edma_read(ctlr, offset);
        val &= and;
        val |= or;
        edma_write(ctlr, offset, val);
}
static inline void edma_and(unsigned ctlr, int offset, unsigned and)
{
        unsigned val = edma_read(ctlr, offset);
        val &= and;
        edma_write(ctlr, offset, val);
}
static inline void edma_or(unsigned ctlr, int offset, unsigned or)
{
        unsigned val = edma_read(ctlr, offset);
        val |= or;
        edma_write(ctlr, offset, val);
}
static inline unsigned int edma_read_array(unsigned ctlr, int offset, int i)
{
        return edma_read(ctlr, offset + (i << 2));
}
static inline void edma_write_array(unsigned ctlr, int offset, int i,
                unsigned val)
{
        edma_write(ctlr, offset + (i << 2), val);
}
static inline void edma_modify_array(unsigned ctlr, int offset, int i,
                unsigned and, unsigned or)
{
        edma_modify(ctlr, offset + (i << 2), and, or);
}
static inline void edma_or_array(unsigned ctlr, int offset, int i, unsigned or)
{
        edma_or(ctlr, offset + (i << 2), or);
}
static inline void edma_or_array2(unsigned ctlr, int offset, int i, int j,
                unsigned or)
{
        edma_or(ctlr, offset + ((i*2 + j) << 2), or);
}
static inline void edma_write_array2(unsigned ctlr, int offset, int i, int j,
                unsigned val)
{
        edma_write(ctlr, offset + ((i*2 + j) << 2), val);
}
static inline unsigned int edma_shadow0_read(unsigned ctlr, int offset)
{
        return edma_read(ctlr, EDMA_SHADOW0 + offset);
}
static inline unsigned int edma_shadow0_read_array(unsigned ctlr, int offset,
                int i)
{
        return edma_read(ctlr, EDMA_SHADOW0 + offset + (i << 2));
}
static inline void edma_shadow0_write(unsigned ctlr, int offset, unsigned val)
{
        edma_write(ctlr, EDMA_SHADOW0 + offset, val);
}
static inline void edma_shadow0_write_array(unsigned ctlr, int offset, int i,
                unsigned val)
{
        edma_write(ctlr, EDMA_SHADOW0 + offset + (i << 2), val);
}
static inline unsigned int edma_parm_read(unsigned ctlr, int offset,
                int param_no)
{
        return edma_read(ctlr, EDMA_PARM + offset + (param_no << 5));
}
static inline void edma_parm_write(unsigned ctlr, int offset, int param_no,
                unsigned val)
{
        edma_write(ctlr, EDMA_PARM + offset + (param_no << 5), val);
}
static inline void edma_parm_modify(unsigned ctlr, int offset, int param_no,
                unsigned and, unsigned or)
{
        edma_modify(ctlr, EDMA_PARM + offset + (param_no << 5), and, or);
}
static inline void edma_parm_and(unsigned ctlr, int offset, int param_no,
                unsigned and)
{
        edma_and(ctlr, EDMA_PARM + offset + (param_no << 5), and);
}
static inline void edma_parm_or(unsigned ctlr, int offset, int param_no,
                unsigned or)
{
        edma_or(ctlr, EDMA_PARM + offset + (param_no << 5), or);
}

static inline void set_bits(int offset, int len, unsigned long *p)
{
        for (; len > 0; len--)
                set_bit(offset + (len - 1), p);
}

static inline void clear_bits(int offset, int len, unsigned long *p)
{
        for (; len > 0; len--)
                clear_bit(offset + (len - 1), p);
}

/*****************************************************************************/

/* actual number of DMA channels and slots on this silicon */
struct edma {
        /* how many dma resources of each type */
        unsigned        num_channels;
        unsigned        num_region;
        unsigned        num_slots;
        unsigned        num_tc;
        unsigned        num_cc;
        enum dma_event_q        default_queue;

        /* list of channels with no even trigger; terminated by "-1" */
        const s8        *noevent;

        /* The edma_inuse bit for each PaRAM slot is clear unless the
         * channel is in use ... by ARM or DSP, for QDMA, or whatever.
         */
        DECLARE_BITMAP(edma_inuse, EDMA_MAX_PARAMENTRY);

        /* The edma_unused bit for each channel is clear unless
         * it is not being used on this platform. It uses a bit
         * of SOC-specific initialization code.
         */
        DECLARE_BITMAP(edma_unused, EDMA_MAX_DMACH);

        unsigned        irq_res_start;
        unsigned        irq_res_end;

        struct dma_interrupt_data {
                void (*callback)(unsigned channel, unsigned short ch_status,
                                void *data);
                void *data;
        } intr_data[EDMA_MAX_DMACH];
};

static struct edma *edma_cc[EDMA_MAX_CC];
static int arch_num_cc;

/* dummy param set used to (re)initialize parameter RAM slots */
static const struct edmacc_param dummy_paramset = {
        .link_bcntrld = 0xffff,
        .ccnt = 1,
};

/*****************************************************************************/

static void map_dmach_queue(unsigned ctlr, unsigned ch_no,
                enum dma_event_q queue_no)
{
        int bit = (ch_no & 0x7) * 4;

        /* default to low priority queue */
        if (queue_no == EVENTQ_DEFAULT)
                queue_no = edma_cc[ctlr]->default_queue;

        queue_no &= 7;
        edma_modify_array(ctlr, EDMA_DMAQNUM, (ch_no >> 3),
                        ~(0x7 << bit), queue_no << bit);
}

static void __init map_queue_tc(unsigned ctlr, int queue_no, int tc_no)
{
        int bit = queue_no * 4;
        edma_modify(ctlr, EDMA_QUETCMAP, ~(0x7 << bit), ((tc_no & 0x7) << bit));
}

static void __init assign_priority_to_queue(unsigned ctlr, int queue_no,
                int priority)
{
        int bit = queue_no * 4;
        edma_modify(ctlr, EDMA_QUEPRI, ~(0x7 << bit),
                        ((priority & 0x7) << bit));
}

/**
 * map_dmach_param - Maps channel number to param entry number
 *
 * This maps the dma channel number to param entry numberter. In
 * other words using the DMA channel mapping registers a param entry
 * can be mapped to any channel
 *
 * Callers are responsible for ensuring the channel mapping logic is
 * included in that particular EDMA variant (Eg : dm646x)
 *
 */
static void __init map_dmach_param(unsigned ctlr)
{
        int i;
        for (i = 0; i < EDMA_MAX_DMACH; i++)
                edma_write_array(ctlr, EDMA_DCHMAP , i , (i << 5));
}

static inline void
setup_dma_interrupt(unsigned lch,
        void (*callback)(unsigned channel, u16 ch_status, void *data),
        void *data)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(lch);
        lch = EDMA_CHAN_SLOT(lch);

        if (!callback)
                edma_shadow0_write_array(ctlr, SH_IECR, lch >> 5,
                                BIT(lch & 0x1f));

        edma_cc[ctlr]->intr_data[lch].callback = callback;
        edma_cc[ctlr]->intr_data[lch].data = data;

        if (callback) {
                edma_shadow0_write_array(ctlr, SH_ICR, lch >> 5,
                                BIT(lch & 0x1f));
                edma_shadow0_write_array(ctlr, SH_IESR, lch >> 5,
                                BIT(lch & 0x1f));
        }
}

static int irq2ctlr(int irq)
{
        if (irq >= edma_cc[0]->irq_res_start && irq <= edma_cc[0]->irq_res_end)
                return 0;
        else if (irq >= edma_cc[1]->irq_res_start &&
                irq <= edma_cc[1]->irq_res_end)
                return 1;

        return -1;
}

/******************************************************************************
 *
 * DMA interrupt handler
 *
 *****************************************************************************/
static irqreturn_t dma_irq_handler(int irq, void *data)
{
        int i;
        int ctlr;
        unsigned int cnt = 0;

        ctlr = irq2ctlr(irq);
        if (ctlr < 0)
                return IRQ_NONE;

        dev_dbg(data, "dma_irq_handler\n");

        if ((edma_shadow0_read_array(ctlr, SH_IPR, 0) == 0) &&
            (edma_shadow0_read_array(ctlr, SH_IPR, 1) == 0))
                return IRQ_NONE;

        while (1) {
                int j;
                if (edma_shadow0_read_array(ctlr, SH_IPR, 0) &
                                edma_shadow0_read_array(ctlr, SH_IER, 0))
                        j = 0;
                else if (edma_shadow0_read_array(ctlr, SH_IPR, 1) &
                                edma_shadow0_read_array(ctlr, SH_IER, 1))
                        j = 1;
                else
                        break;
                dev_dbg(data, "IPR%d %08x\n", j,
                                edma_shadow0_read_array(ctlr, SH_IPR, j));
                for (i = 0; i < 32; i++) {
                        int k = (j << 5) + i;
                        if ((edma_shadow0_read_array(ctlr, SH_IPR, j) & BIT(i))
                                        && (edma_shadow0_read_array(ctlr,
                                                        SH_IER, j) & BIT(i))) {
                                /* Clear the corresponding IPR bits */
                                edma_shadow0_write_array(ctlr, SH_ICR, j,
                                                        BIT(i));
                                if (edma_cc[ctlr]->intr_data[k].callback)
                                        edma_cc[ctlr]->intr_data[k].callback(
                                                k, DMA_COMPLETE,
                                                edma_cc[ctlr]->intr_data[k].
                                                data);
                        }
                }
                cnt++;
                if (cnt > 10)
                        break;
        }
        edma_shadow0_write(ctlr, SH_IEVAL, 1);
        return IRQ_HANDLED;
}

/******************************************************************************
 *
 * DMA error interrupt handler
 *
 *****************************************************************************/
static irqreturn_t dma_ccerr_handler(int irq, void *data)
{
        int i;
        int ctlr;
        unsigned int cnt = 0;

        ctlr = irq2ctlr(irq);
        if (ctlr < 0)
                return IRQ_NONE;

        dev_dbg(data, "dma_ccerr_handler\n");

        if ((edma_read_array(ctlr, EDMA_EMR, 0) == 0) &&
            (edma_read_array(ctlr, EDMA_EMR, 1) == 0) &&
            (edma_read(ctlr, EDMA_QEMR) == 0) &&
            (edma_read(ctlr, EDMA_CCERR) == 0))
                return IRQ_NONE;

        while (1) {
                int j = -1;
                if (edma_read_array(ctlr, EDMA_EMR, 0))
                        j = 0;
                else if (edma_read_array(ctlr, EDMA_EMR, 1))
                        j = 1;
                if (j >= 0) {
                        dev_dbg(data, "EMR%d %08x\n", j,
                                        edma_read_array(ctlr, EDMA_EMR, j));
                        for (i = 0; i < 32; i++) {
                                int k = (j << 5) + i;
                                if (edma_read_array(ctlr, EDMA_EMR, j) &
                                                        BIT(i)) {
                                        /* Clear the corresponding EMR bits */
                                        edma_write_array(ctlr, EDMA_EMCR, j,
                                                        BIT(i));
                                        /* Clear any SER */
                                        edma_shadow0_write_array(ctlr, SH_SECR,
                                                                j, BIT(i));
                                        if (edma_cc[ctlr]->intr_data[k].
                                                                callback) {
                                                edma_cc[ctlr]->intr_data[k].
                                                callback(k,
                                                DMA_CC_ERROR,
                                                edma_cc[ctlr]->intr_data
                                                [k].data);
                                        }
                                }
                        }
                } else if (edma_read(ctlr, EDMA_QEMR)) {
                        dev_dbg(data, "QEMR %02x\n",
                                edma_read(ctlr, EDMA_QEMR));
                        for (i = 0; i < 8; i++) {
                                if (edma_read(ctlr, EDMA_QEMR) & BIT(i)) {
                                        /* Clear the corresponding IPR bits */
                                        edma_write(ctlr, EDMA_QEMCR, BIT(i));
                                        edma_shadow0_write(ctlr, SH_QSECR,
                                                                BIT(i));

                                        /* NOTE:  not reported!! */
                                }
                        }
                } else if (edma_read(ctlr, EDMA_CCERR)) {
                        dev_dbg(data, "CCERR %08x\n",
                                edma_read(ctlr, EDMA_CCERR));
                        /* FIXME:  CCERR.BIT(16) ignored!  much better
                         * to just write CCERRCLR with CCERR value...
                         */
                        for (i = 0; i < 8; i++) {
                                if (edma_read(ctlr, EDMA_CCERR) & BIT(i)) {
                                        /* Clear the corresponding IPR bits */
                                        edma_write(ctlr, EDMA_CCERRCLR, BIT(i));

                                        /* NOTE:  not reported!! */
                                }
                        }
                }
                if ((edma_read_array(ctlr, EDMA_EMR, 0) == 0) &&
                    (edma_read_array(ctlr, EDMA_EMR, 1) == 0) &&
                    (edma_read(ctlr, EDMA_QEMR) == 0) &&
                    (edma_read(ctlr, EDMA_CCERR) == 0))
                        break;
                cnt++;
                if (cnt > 10)
                        break;
        }
        edma_write(ctlr, EDMA_EEVAL, 1);
        return IRQ_HANDLED;
}

/******************************************************************************
 *
 * Transfer controller error interrupt handlers
 *
 *****************************************************************************/

#define tc_errs_handled false   /* disabled as long as they're NOPs */

static irqreturn_t dma_tc0err_handler(int irq, void *data)
{
        dev_dbg(data, "dma_tc0err_handler\n");
        return IRQ_HANDLED;
}

static irqreturn_t dma_tc1err_handler(int irq, void *data)
{
        dev_dbg(data, "dma_tc1err_handler\n");
        return IRQ_HANDLED;
}

static int reserve_contiguous_slots(int ctlr, unsigned int id,
                                     unsigned int num_slots,
                                     unsigned int start_slot)
{
        int i, j;
        unsigned int count = num_slots;
        int stop_slot = start_slot;
        DECLARE_BITMAP(tmp_inuse, EDMA_MAX_PARAMENTRY);

        for (i = start_slot; i < edma_cc[ctlr]->num_slots; ++i) {
                j = EDMA_CHAN_SLOT(i);
                if (!test_and_set_bit(j, edma_cc[ctlr]->edma_inuse)) {
                        /* Record our current beginning slot */
                        if (count == num_slots)
                                stop_slot = i;

                        count--;
                        set_bit(j, tmp_inuse);

                        if (count == 0)
                                break;
                } else {
                        clear_bit(j, tmp_inuse);

                        if (id == EDMA_CONT_PARAMS_FIXED_EXACT) {
                                stop_slot = i;
                                break;
                        } else {
                                count = num_slots;
                        }
                }
        }

        /*
         * We have to clear any bits that we set
         * if we run out parameter RAM slots, i.e we do find a set
         * of contiguous parameter RAM slots but do not find the exact number
         * requested as we may reach the total number of parameter RAM slots
         */
        if (i == edma_cc[ctlr]->num_slots)
                stop_slot = i;

        for (j = start_slot; j < stop_slot; j++)
                if (test_bit(j, tmp_inuse))
                        clear_bit(j, edma_cc[ctlr]->edma_inuse);

        if (count)
                return -EBUSY;

        for (j = i - num_slots + 1; j <= i; ++j)
                memcpy_toio(edmacc_regs_base[ctlr] + PARM_OFFSET(j),
                        &dummy_paramset, PARM_SIZE);

        return EDMA_CTLR_CHAN(ctlr, i - num_slots + 1);
}

static int prepare_unused_channel_list(struct device *dev, void *data)
{
        struct platform_device *pdev = to_platform_device(dev);
        int i, ctlr;

        for (i = 0; i < pdev->num_resources; i++) {
                if ((pdev->resource[i].flags & IORESOURCE_DMA) &&
                                (int)pdev->resource[i].start >= 0) {
                        ctlr = EDMA_CTLR(pdev->resource[i].start);
                        clear_bit(EDMA_CHAN_SLOT(pdev->resource[i].start),
                                        edma_cc[ctlr]->edma_unused);
                }
        }

        return 0;
}

/*-----------------------------------------------------------------------*/

static bool unused_chan_list_done;

/* Resource alloc/free:  dma channels, parameter RAM slots */

/**
 * edma_alloc_channel - allocate DMA channel and paired parameter RAM
 * @channel: specific channel to allocate; negative for "any unmapped channel"
 * @callback: optional; to be issued on DMA completion or errors
 * @data: passed to callback
 * @eventq_no: an EVENTQ_* constant, used to choose which Transfer
 *      Controller (TC) executes requests using this channel.  Use
 *      EVENTQ_DEFAULT unless you really need a high priority queue.
 *
 * This allocates a DMA channel and its associated parameter RAM slot.
 * The parameter RAM is initialized to hold a dummy transfer.
 *
 * Normal use is to pass a specific channel number as @channel, to make
 * use of hardware events mapped to that channel.  When the channel will
 * be used only for software triggering or event chaining, channels not
 * mapped to hardware events (or mapped to unused events) are preferable.
 *
 * DMA transfers start from a channel using edma_start(), or by
 * chaining.  When the transfer described in that channel's parameter RAM
 * slot completes, that slot's data may be reloaded through a link.
 *
 * DMA errors are only reported to the @callback associated with the
 * channel driving that transfer, but transfer completion callbacks can
 * be sent to another channel under control of the TCC field in
 * the option word of the transfer's parameter RAM set.  Drivers must not
 * use DMA transfer completion callbacks for channels they did not allocate.
 * (The same applies to TCC codes used in transfer chaining.)
 *
 * Returns the number of the channel, else negative errno.
 */
int edma_alloc_channel(int channel,
                void (*callback)(unsigned channel, u16 ch_status, void *data),
                void *data,
                enum dma_event_q eventq_no)
{
        unsigned i, done = 0, ctlr = 0;
        int ret = 0;

        if (!unused_chan_list_done) {
                /*
                 * Scan all the platform devices to find out the EDMA channels
                 * used and clear them in the unused list, making the rest
                 * available for ARM usage.
                 */
                ret = bus_for_each_dev(&platform_bus_type, NULL, NULL,
                                prepare_unused_channel_list);
                if (ret < 0)
                        return ret;

                unused_chan_list_done = true;
        }

        if (channel >= 0) {
                ctlr = EDMA_CTLR(channel);
                channel = EDMA_CHAN_SLOT(channel);
        }

        if (channel < 0) {
                for (i = 0; i < arch_num_cc; i++) {
                        channel = 0;
                        for (;;) {
                                channel = find_next_bit(edma_cc[i]->edma_unused,
                                                edma_cc[i]->num_channels,
                                                channel);
                                if (channel == edma_cc[i]->num_channels)
                                        break;
                                if (!test_and_set_bit(channel,
                                                edma_cc[i]->edma_inuse)) {
                                        done = 1;
                                        ctlr = i;
                                        break;
                                }
                                channel++;
                        }
                        if (done)
                                break;
                }
                if (!done)
                        return -ENOMEM;
        } else if (channel >= edma_cc[ctlr]->num_channels) {
                return -EINVAL;
        } else if (test_and_set_bit(channel, edma_cc[ctlr]->edma_inuse)) {
                return -EBUSY;
        }

        /* ensure access through shadow region 0 */
        edma_or_array2(ctlr, EDMA_DRAE, 0, channel >> 5, BIT(channel & 0x1f));

        /* ensure no events are pending */
        edma_stop(EDMA_CTLR_CHAN(ctlr, channel));
        memcpy_toio(edmacc_regs_base[ctlr] + PARM_OFFSET(channel),
                        &dummy_paramset, PARM_SIZE);

        if (callback)
                setup_dma_interrupt(EDMA_CTLR_CHAN(ctlr, channel),
                                        callback, data);

        map_dmach_queue(ctlr, channel, eventq_no);

        return EDMA_CTLR_CHAN(ctlr, channel);
}
EXPORT_SYMBOL(edma_alloc_channel);


/**
 * edma_free_channel - deallocate DMA channel
 * @channel: dma channel returned from edma_alloc_channel()
 *
 * This deallocates the DMA channel and associated parameter RAM slot
 * allocated by edma_alloc_channel().
 *
 * Callers are responsible for ensuring the channel is inactive, and
 * will not be reactivated by linking, chaining, or software calls to
 * edma_start().
 */
void edma_free_channel(unsigned channel)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(channel);
        channel = EDMA_CHAN_SLOT(channel);

        if (channel >= edma_cc[ctlr]->num_channels)
                return;

        setup_dma_interrupt(channel, NULL, NULL);
        /* REVISIT should probably take out of shadow region 0 */

        memcpy_toio(edmacc_regs_base[ctlr] + PARM_OFFSET(channel),
                        &dummy_paramset, PARM_SIZE);
        clear_bit(channel, edma_cc[ctlr]->edma_inuse);
}
EXPORT_SYMBOL(edma_free_channel);

/**
 * edma_alloc_slot - allocate DMA parameter RAM
 * @slot: specific slot to allocate; negative for "any unused slot"
 *
 * This allocates a parameter RAM slot, initializing it to hold a
 * dummy transfer.  Slots allocated using this routine have not been
 * mapped to a hardware DMA channel, and will normally be used by
 * linking to them from a slot associated with a DMA channel.
 *
 * Normal use is to pass EDMA_SLOT_ANY as the @slot, but specific
 * slots may be allocated on behalf of DSP firmware.
 *
 * Returns the number of the slot, else negative errno.
 */
int edma_alloc_slot(unsigned ctlr, int slot)
{
        if (slot >= 0)
                slot = EDMA_CHAN_SLOT(slot);

        if (slot < 0) {
                slot = edma_cc[ctlr]->num_channels;
                for (;;) {
                        slot = find_next_zero_bit(edma_cc[ctlr]->edma_inuse,
                                        edma_cc[ctlr]->num_slots, slot);
                        if (slot == edma_cc[ctlr]->num_slots)
                                return -ENOMEM;
                        if (!test_and_set_bit(slot, edma_cc[ctlr]->edma_inuse))
                                break;
                }
        } else if (slot < edma_cc[ctlr]->num_channels ||
                        slot >= edma_cc[ctlr]->num_slots) {
                return -EINVAL;
        } else if (test_and_set_bit(slot, edma_cc[ctlr]->edma_inuse)) {
                return -EBUSY;
        }

        memcpy_toio(edmacc_regs_base[ctlr] + PARM_OFFSET(slot),
                        &dummy_paramset, PARM_SIZE);

        return EDMA_CTLR_CHAN(ctlr, slot);
}
EXPORT_SYMBOL(edma_alloc_slot);

/**
 * edma_free_slot - deallocate DMA parameter RAM
 * @slot: parameter RAM slot returned from edma_alloc_slot()
 *
 * This deallocates the parameter RAM slot allocated by edma_alloc_slot().
 * Callers are responsible for ensuring the slot is inactive, and will
 * not be activated.
 */
void edma_free_slot(unsigned slot)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(slot);
        slot = EDMA_CHAN_SLOT(slot);

        if (slot < edma_cc[ctlr]->num_channels ||
                slot >= edma_cc[ctlr]->num_slots)
                return;

        memcpy_toio(edmacc_regs_base[ctlr] + PARM_OFFSET(slot),
                        &dummy_paramset, PARM_SIZE);
        clear_bit(slot, edma_cc[ctlr]->edma_inuse);
}
EXPORT_SYMBOL(edma_free_slot);


/**
 * edma_alloc_cont_slots- alloc contiguous parameter RAM slots
 * The API will return the starting point of a set of
 * contiguous parameter RAM slots that have been requested
 *
 * @id: can only be EDMA_CONT_PARAMS_ANY or EDMA_CONT_PARAMS_FIXED_EXACT
 * or EDMA_CONT_PARAMS_FIXED_NOT_EXACT
 * @count: number of contiguous Paramter RAM slots
 * @slot  - the start value of Parameter RAM slot that should be passed if id
 * is EDMA_CONT_PARAMS_FIXED_EXACT or EDMA_CONT_PARAMS_FIXED_NOT_EXACT
 *
 * If id is EDMA_CONT_PARAMS_ANY then the API starts looking for a set of
 * contiguous Parameter RAM slots from parameter RAM 64 in the case of
 * DaVinci SOCs and 32 in the case of DA8xx SOCs.
 *
 * If id is EDMA_CONT_PARAMS_FIXED_EXACT then the API starts looking for a
 * set of contiguous parameter RAM slots from the "slot" that is passed as an
 * argument to the API.
 *
 * If id is EDMA_CONT_PARAMS_FIXED_NOT_EXACT then the API initially tries
 * starts looking for a set of contiguous parameter RAMs from the "slot"
 * that is passed as an argument to the API. On failure the API will try to
 * find a set of contiguous Parameter RAM slots from the remaining Parameter
 * RAM slots
 */
int edma_alloc_cont_slots(unsigned ctlr, unsigned int id, int slot, int count)
{
        /*
         * The start slot requested should be greater than
         * the number of channels and lesser than the total number
         * of slots
         */
        if ((id != EDMA_CONT_PARAMS_ANY) &&
                (slot < edma_cc[ctlr]->num_channels ||
                slot >= edma_cc[ctlr]->num_slots))
                return -EINVAL;

        /*
         * The number of parameter RAM slots requested cannot be less than 1
         * and cannot be more than the number of slots minus the number of
         * channels
         */
        if (count < 1 || count >
                (edma_cc[ctlr]->num_slots - edma_cc[ctlr]->num_channels))
                return -EINVAL;

        switch (id) {
        case EDMA_CONT_PARAMS_ANY:
                return reserve_contiguous_slots(ctlr, id, count,
                                                 edma_cc[ctlr]->num_channels);
        case EDMA_CONT_PARAMS_FIXED_EXACT:
        case EDMA_CONT_PARAMS_FIXED_NOT_EXACT:
                return reserve_contiguous_slots(ctlr, id, count, slot);
        default:
                return -EINVAL;
        }

}
EXPORT_SYMBOL(edma_alloc_cont_slots);

/**
 * edma_free_cont_slots - deallocate DMA parameter RAM slots
 * @slot: first parameter RAM of a set of parameter RAM slots to be freed
 * @count: the number of contiguous parameter RAM slots to be freed
 *
 * This deallocates the parameter RAM slots allocated by
 * edma_alloc_cont_slots.
 * Callers/applications need to keep track of sets of contiguous
 * parameter RAM slots that have been allocated using the edma_alloc_cont_slots
 * API.
 * Callers are responsible for ensuring the slots are inactive, and will
 * not be activated.
 */
int edma_free_cont_slots(unsigned slot, int count)
{
        unsigned ctlr, slot_to_free;
        int i;

        ctlr = EDMA_CTLR(slot);
        slot = EDMA_CHAN_SLOT(slot);

        if (slot < edma_cc[ctlr]->num_channels ||
                slot >= edma_cc[ctlr]->num_slots ||
                count < 1)
                return -EINVAL;

        for (i = slot; i < slot + count; ++i) {
                ctlr = EDMA_CTLR(i);
                slot_to_free = EDMA_CHAN_SLOT(i);

                memcpy_toio(edmacc_regs_base[ctlr] + PARM_OFFSET(slot_to_free),
                        &dummy_paramset, PARM_SIZE);
                clear_bit(slot_to_free, edma_cc[ctlr]->edma_inuse);
        }

        return 0;
}
EXPORT_SYMBOL(edma_free_cont_slots);

/*-----------------------------------------------------------------------*/

/* Parameter RAM operations (i) -- read/write partial slots */

/**
 * edma_set_src - set initial DMA source address in parameter RAM slot
 * @slot: parameter RAM slot being configured
 * @src_port: physical address of source (memory, controller FIFO, etc)
 * @addressMode: INCR, except in very rare cases
 * @fifoWidth: ignored unless @addressMode is FIFO, else specifies the
 *      width to use when addressing the fifo (e.g. W8BIT, W32BIT)
 *
 * Note that the source address is modified during the DMA transfer
 * according to edma_set_src_index().
 */
void edma_set_src(unsigned slot, dma_addr_t src_port,
                                enum address_mode mode, enum fifo_width width)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(slot);
        slot = EDMA_CHAN_SLOT(slot);

        if (slot < edma_cc[ctlr]->num_slots) {
                unsigned int i = edma_parm_read(ctlr, PARM_OPT, slot);

                if (mode) {
                        /* set SAM and program FWID */
                        i = (i & ~(EDMA_FWID)) | (SAM | ((width & 0x7) << 8));
                } else {
                        /* clear SAM */
                        i &= ~SAM;
                }
                edma_parm_write(ctlr, PARM_OPT, slot, i);

                /* set the source port address
                   in source register of param structure */
                edma_parm_write(ctlr, PARM_SRC, slot, src_port);
        }
}
EXPORT_SYMBOL(edma_set_src);

/**
 * edma_set_dest - set initial DMA destination address in parameter RAM slot
 * @slot: parameter RAM slot being configured
 * @dest_port: physical address of destination (memory, controller FIFO, etc)
 * @addressMode: INCR, except in very rare cases
 * @fifoWidth: ignored unless @addressMode is FIFO, else specifies the
 *      width to use when addressing the fifo (e.g. W8BIT, W32BIT)
 *
 * Note that the destination address is modified during the DMA transfer
 * according to edma_set_dest_index().
 */
void edma_set_dest(unsigned slot, dma_addr_t dest_port,
                                 enum address_mode mode, enum fifo_width width)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(slot);
        slot = EDMA_CHAN_SLOT(slot);

        if (slot < edma_cc[ctlr]->num_slots) {
                unsigned int i = edma_parm_read(ctlr, PARM_OPT, slot);

                if (mode) {
                        /* set DAM and program FWID */
                        i = (i & ~(EDMA_FWID)) | (DAM | ((width & 0x7) << 8));
                } else {
                        /* clear DAM */
                        i &= ~DAM;
                }
                edma_parm_write(ctlr, PARM_OPT, slot, i);
                /* set the destination port address
                   in dest register of param structure */
                edma_parm_write(ctlr, PARM_DST, slot, dest_port);
        }
}
EXPORT_SYMBOL(edma_set_dest);

/**
 * edma_get_position - returns the current transfer points
 * @slot: parameter RAM slot being examined
 * @src: pointer to source port position
 * @dst: pointer to destination port position
 *
 * Returns current source and destination addresses for a particular
 * parameter RAM slot.  Its channel should not be active when this is called.
 */
void edma_get_position(unsigned slot, dma_addr_t *src, dma_addr_t *dst)
{
        struct edmacc_param temp;
        unsigned ctlr;

        ctlr = EDMA_CTLR(slot);
        slot = EDMA_CHAN_SLOT(slot);

        edma_read_slot(EDMA_CTLR_CHAN(ctlr, slot), &temp);
        if (src != NULL)
                *src = temp.src;
        if (dst != NULL)
                *dst = temp.dst;
}
EXPORT_SYMBOL(edma_get_position);

/**
 * edma_set_src_index - configure DMA source address indexing
 * @slot: parameter RAM slot being configured
 * @src_bidx: byte offset between source arrays in a frame
 * @src_cidx: byte offset between source frames in a block
 *
 * Offsets are specified to support either contiguous or discontiguous
 * memory transfers, or repeated access to a hardware register, as needed.
 * When accessing hardware registers, both offsets are normally zero.
 */
void edma_set_src_index(unsigned slot, s16 src_bidx, s16 src_cidx)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(slot);
        slot = EDMA_CHAN_SLOT(slot);

        if (slot < edma_cc[ctlr]->num_slots) {
                edma_parm_modify(ctlr, PARM_SRC_DST_BIDX, slot,
                                0xffff0000, src_bidx);
                edma_parm_modify(ctlr, PARM_SRC_DST_CIDX, slot,
                                0xffff0000, src_cidx);
        }
}
EXPORT_SYMBOL(edma_set_src_index);

/**
 * edma_set_dest_index - configure DMA destination address indexing
 * @slot: parameter RAM slot being configured
 * @dest_bidx: byte offset between destination arrays in a frame
 * @dest_cidx: byte offset between destination frames in a block
 *
 * Offsets are specified to support either contiguous or discontiguous
 * memory transfers, or repeated access to a hardware register, as needed.
 * When accessing hardware registers, both offsets are normally zero.
 */
void edma_set_dest_index(unsigned slot, s16 dest_bidx, s16 dest_cidx)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(slot);
        slot = EDMA_CHAN_SLOT(slot);

        if (slot < edma_cc[ctlr]->num_slots) {
                edma_parm_modify(ctlr, PARM_SRC_DST_BIDX, slot,
                                0x0000ffff, dest_bidx << 16);
                edma_parm_modify(ctlr, PARM_SRC_DST_CIDX, slot,
                                0x0000ffff, dest_cidx << 16);
        }
}
EXPORT_SYMBOL(edma_set_dest_index);

/**
 * edma_set_transfer_params - configure DMA transfer parameters
 * @slot: parameter RAM slot being configured
 * @acnt: how many bytes per array (at least one)
 * @bcnt: how many arrays per frame (at least one)
 * @ccnt: how many frames per block (at least one)
 * @bcnt_rld: used only for A-Synchronized transfers; this specifies
 *      the value to reload into bcnt when it decrements to zero
 * @sync_mode: ASYNC or ABSYNC
 *
 * See the EDMA3 documentation to understand how to configure and link
 * transfers using the fields in PaRAM slots.  If you are not doing it
 * all at once with edma_write_slot(), you will use this routine
 * plus two calls each for source and destination, setting the initial
 * address and saying how to index that address.
 *
 * An example of an A-Synchronized transfer is a serial link using a
 * single word shift register.  In that case, @acnt would be equal to
 * that word size; the serial controller issues a DMA synchronization
 * event to transfer each word, and memory access by the DMA transfer
 * controller will be word-at-a-time.
 *
 * An example of an AB-Synchronized transfer is a device using a FIFO.
 * In that case, @acnt equals the FIFO width and @bcnt equals its depth.
 * The controller with the FIFO issues DMA synchronization events when
 * the FIFO threshold is reached, and the DMA transfer controller will
 * transfer one frame to (or from) the FIFO.  It will probably use
 * efficient burst modes to access memory.
 */
void edma_set_transfer_params(unsigned slot,
                u16 acnt, u16 bcnt, u16 ccnt,
                u16 bcnt_rld, enum sync_dimension sync_mode)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(slot);
        slot = EDMA_CHAN_SLOT(slot);

        if (slot < edma_cc[ctlr]->num_slots) {
                edma_parm_modify(ctlr, PARM_LINK_BCNTRLD, slot,
                                0x0000ffff, bcnt_rld << 16);
                if (sync_mode == ASYNC)
                        edma_parm_and(ctlr, PARM_OPT, slot, ~SYNCDIM);
                else
                        edma_parm_or(ctlr, PARM_OPT, slot, SYNCDIM);
                /* Set the acount, bcount, ccount registers */
                edma_parm_write(ctlr, PARM_A_B_CNT, slot, (bcnt << 16) | acnt);
                edma_parm_write(ctlr, PARM_CCNT, slot, ccnt);
        }
}
EXPORT_SYMBOL(edma_set_transfer_params);

/**
 * edma_link - link one parameter RAM slot to another
 * @from: parameter RAM slot originating the link
 * @to: parameter RAM slot which is the link target
 *
 * The originating slot should not be part of any active DMA transfer.
 */
void edma_link(unsigned from, unsigned to)
{
        unsigned ctlr_from, ctlr_to;

        ctlr_from = EDMA_CTLR(from);
        from = EDMA_CHAN_SLOT(from);
        ctlr_to = EDMA_CTLR(to);
        to = EDMA_CHAN_SLOT(to);

        if (from >= edma_cc[ctlr_from]->num_slots)
                return;
        if (to >= edma_cc[ctlr_to]->num_slots)
                return;
        edma_parm_modify(ctlr_from, PARM_LINK_BCNTRLD, from, 0xffff0000,
                                PARM_OFFSET(to));
}
EXPORT_SYMBOL(edma_link);

/**
 * edma_unlink - cut link from one parameter RAM slot
 * @from: parameter RAM slot originating the link
 *
 * The originating slot should not be part of any active DMA transfer.
 * Its link is set to 0xffff.
 */
void edma_unlink(unsigned from)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(from);
        from = EDMA_CHAN_SLOT(from);

        if (from >= edma_cc[ctlr]->num_slots)
                return;
        edma_parm_or(ctlr, PARM_LINK_BCNTRLD, from, 0xffff);
}
EXPORT_SYMBOL(edma_unlink);

/*-----------------------------------------------------------------------*/

/* Parameter RAM operations (ii) -- read/write whole parameter sets */

/**
 * edma_write_slot - write parameter RAM data for slot
 * @slot: number of parameter RAM slot being modified
 * @param: data to be written into parameter RAM slot
 *
 * Use this to assign all parameters of a transfer at once.  This
 * allows more efficient setup of transfers than issuing multiple
 * calls to set up those parameters in small pieces, and provides
 * complete control over all transfer options.
 */
void edma_write_slot(unsigned slot, const struct edmacc_param *param)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(slot);
        slot = EDMA_CHAN_SLOT(slot);

        if (slot >= edma_cc[ctlr]->num_slots)
                return;
        memcpy_toio(edmacc_regs_base[ctlr] + PARM_OFFSET(slot), param,
                        PARM_SIZE);
}
EXPORT_SYMBOL(edma_write_slot);

/**
 * edma_read_slot - read parameter RAM data from slot
 * @slot: number of parameter RAM slot being copied
 * @param: where to store copy of parameter RAM data
 *
 * Use this to read data from a parameter RAM slot, perhaps to
 * save them as a template for later reuse.
 */
void edma_read_slot(unsigned slot, struct edmacc_param *param)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(slot);
        slot = EDMA_CHAN_SLOT(slot);

        if (slot >= edma_cc[ctlr]->num_slots)
                return;
        memcpy_fromio(param, edmacc_regs_base[ctlr] + PARM_OFFSET(slot),
                        PARM_SIZE);
}
EXPORT_SYMBOL(edma_read_slot);

/*-----------------------------------------------------------------------*/

/* Various EDMA channel control operations */

/**
 * edma_pause - pause dma on a channel
 * @channel: on which edma_start() has been called
 *
 * This temporarily disables EDMA hardware events on the specified channel,
 * preventing them from triggering new transfers on its behalf
 */
void edma_pause(unsigned channel)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(channel);
        channel = EDMA_CHAN_SLOT(channel);

        if (channel < edma_cc[ctlr]->num_channels) {
                unsigned int mask = BIT(channel & 0x1f);

                edma_shadow0_write_array(ctlr, SH_EECR, channel >> 5, mask);
        }
}
EXPORT_SYMBOL(edma_pause);

/**
 * edma_resume - resumes dma on a paused channel
 * @channel: on which edma_pause() has been called
 *
 * This re-enables EDMA hardware events on the specified channel.
 */
void edma_resume(unsigned channel)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(channel);
        channel = EDMA_CHAN_SLOT(channel);

        if (channel < edma_cc[ctlr]->num_channels) {
                unsigned int mask = BIT(channel & 0x1f);

                edma_shadow0_write_array(ctlr, SH_EESR, channel >> 5, mask);
        }
}
EXPORT_SYMBOL(edma_resume);

/**
 * edma_start - start dma on a channel
 * @channel: channel being activated
 *
 * Channels with event associations will be triggered by their hardware
 * events, and channels without such associations will be triggered by
 * software.  (At this writing there is no interface for using software
 * triggers except with channels that don't support hardware triggers.)
 *
 * Returns zero on success, else negative errno.
 */
int edma_start(unsigned channel)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(channel);
        channel = EDMA_CHAN_SLOT(channel);

        if (channel < edma_cc[ctlr]->num_channels) {
                int j = channel >> 5;
                unsigned int mask = BIT(channel & 0x1f);

                /* EDMA channels without event association */
                if (test_bit(channel, edma_cc[ctlr]->edma_unused)) {
                        pr_debug("EDMA: ESR%d %08x\n", j,
                                edma_shadow0_read_array(ctlr, SH_ESR, j));
                        edma_shadow0_write_array(ctlr, SH_ESR, j, mask);
                        return 0;
                }

                /* EDMA channel with event association */
                pr_debug("EDMA: ER%d %08x\n", j,
                        edma_shadow0_read_array(ctlr, SH_ER, j));
                /* Clear any pending event or error */
                edma_write_array(ctlr, EDMA_ECR, j, mask);
                edma_write_array(ctlr, EDMA_EMCR, j, mask);
                /* Clear any SER */
                edma_shadow0_write_array(ctlr, SH_SECR, j, mask);
                edma_shadow0_write_array(ctlr, SH_EESR, j, mask);
                pr_debug("EDMA: EER%d %08x\n", j,
                        edma_shadow0_read_array(ctlr, SH_EER, j));
                return 0;
        }

        return -EINVAL;
}
EXPORT_SYMBOL(edma_start);

/**
 * edma_stop - stops dma on the channel passed
 * @channel: channel being deactivated
 *
 * When @lch is a channel, any active transfer is paused and
 * all pending hardware events are cleared.  The current transfer
 * may not be resumed, and the channel's Parameter RAM should be
 * reinitialized before being reused.
 */
void edma_stop(unsigned channel)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(channel);
        channel = EDMA_CHAN_SLOT(channel);

        if (channel < edma_cc[ctlr]->num_channels) {
                int j = channel >> 5;
                unsigned int mask = BIT(channel & 0x1f);

                edma_shadow0_write_array(ctlr, SH_EECR, j, mask);
                edma_shadow0_write_array(ctlr, SH_ECR, j, mask);
                edma_shadow0_write_array(ctlr, SH_SECR, j, mask);
                edma_write_array(ctlr, EDMA_EMCR, j, mask);

                pr_debug("EDMA: EER%d %08x\n", j,
                                edma_shadow0_read_array(ctlr, SH_EER, j));

                /* REVISIT:  consider guarding against inappropriate event
                 * chaining by overwriting with dummy_paramset.
                 */
        }
}
EXPORT_SYMBOL(edma_stop);

/******************************************************************************
 *
 * It cleans ParamEntry qand bring back EDMA to initial state if media has
 * been removed before EDMA has finished.It is usedful for removable media.
 * Arguments:
 *      ch_no     - channel no
 *
 * Return: zero on success, or corresponding error no on failure
 *
 * FIXME this should not be needed ... edma_stop() should suffice.
 *
 *****************************************************************************/

void edma_clean_channel(unsigned channel)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(channel);
        channel = EDMA_CHAN_SLOT(channel);

        if (channel < edma_cc[ctlr]->num_channels) {
                int j = (channel >> 5);
                unsigned int mask = BIT(channel & 0x1f);

                pr_debug("EDMA: EMR%d %08x\n", j,
                                edma_read_array(ctlr, EDMA_EMR, j));
                edma_shadow0_write_array(ctlr, SH_ECR, j, mask);
                /* Clear the corresponding EMR bits */
                edma_write_array(ctlr, EDMA_EMCR, j, mask);
                /* Clear any SER */
                edma_shadow0_write_array(ctlr, SH_SECR, j, mask);
                edma_write(ctlr, EDMA_CCERRCLR, BIT(16) | BIT(1) | BIT(0));
        }
}
EXPORT_SYMBOL(edma_clean_channel);

/*
 * edma_clear_event - clear an outstanding event on the DMA channel
 * Arguments:
 *      channel - channel number
 */
void edma_clear_event(unsigned channel)
{
        unsigned ctlr;

        ctlr = EDMA_CTLR(channel);
        channel = EDMA_CHAN_SLOT(channel);

        if (channel >= edma_cc[ctlr]->num_channels)
                return;
        if (channel < 32)
                edma_write(ctlr, EDMA_ECR, BIT(channel));
        else
                edma_write(ctlr, EDMA_ECRH, BIT(channel - 32));
}
EXPORT_SYMBOL(edma_clear_event);

/*-----------------------------------------------------------------------*/

static int __init edma_probe(struct platform_device *pdev)
{
        struct edma_soc_info    **info = pdev->dev.platform_data;
        const s8                (*queue_priority_mapping)[2];
        const s8                (*queue_tc_mapping)[2];
        int                     i, j, off, ln, found = 0;
        int                     status = -1;
        const s16               (*rsv_chans)[2];
        const s16               (*rsv_slots)[2];
        int                     irq[EDMA_MAX_CC] = {0, 0};
        int                     err_irq[EDMA_MAX_CC] = {0, 0};
        struct resource         *r[EDMA_MAX_CC] = {NULL};
        resource_size_t         len[EDMA_MAX_CC];
        char                    res_name[10];
        char                    irq_name[10];

        if (!info)
                return -ENODEV;

        for (j = 0; j < EDMA_MAX_CC; j++) {
                sprintf(res_name, "edma_cc%d", j);
                r[j] = platform_get_resource_byname(pdev, IORESOURCE_MEM,
                                                res_name);
                if (!r[j] || !info[j]) {
                        if (found)
                                break;
                        else
                                return -ENODEV;
                } else {
                        found = 1;
                }

                len[j] = resource_size(r[j]);

                r[j] = request_mem_region(r[j]->start, len[j],
                        dev_name(&pdev->dev));
                if (!r[j]) {
                        status = -EBUSY;
                        goto fail1;
                }

                edmacc_regs_base[j] = ioremap(r[j]->start, len[j]);
                if (!edmacc_regs_base[j]) {
                        status = -EBUSY;
                        goto fail1;
                }

                edma_cc[j] = kmalloc(sizeof(struct edma), GFP_KERNEL);
                if (!edma_cc[j]) {
                        status = -ENOMEM;
                        goto fail1;
                }
                memset(edma_cc[j], 0, sizeof(struct edma));

                edma_cc[j]->num_channels = min_t(unsigned, info[j]->n_channel,
                                                        EDMA_MAX_DMACH);
                edma_cc[j]->num_slots = min_t(unsigned, info[j]->n_slot,
                                                        EDMA_MAX_PARAMENTRY);
                edma_cc[j]->num_cc = min_t(unsigned, info[j]->n_cc,
                                                        EDMA_MAX_CC);

                edma_cc[j]->default_queue = info[j]->default_queue;
                if (!edma_cc[j]->default_queue)
                        edma_cc[j]->default_queue = EVENTQ_1;

                dev_dbg(&pdev->dev, "DMA REG BASE ADDR=%p\n",
                        edmacc_regs_base[j]);

                for (i = 0; i < edma_cc[j]->num_slots; i++)
                        memcpy_toio(edmacc_regs_base[j] + PARM_OFFSET(i),
                                        &dummy_paramset, PARM_SIZE);

                /* Mark all channels as unused */
                memset(edma_cc[j]->edma_unused, 0xff,
                        sizeof(edma_cc[j]->edma_unused));

                if (info[j]->rsv) {

                        /* Clear the reserved channels in unused list */
                        rsv_chans = info[j]->rsv->rsv_chans;
                        if (rsv_chans) {
                                for (i = 0; rsv_chans[i][0] != -1; i++) {
                                        off = rsv_chans[i][0];
                                        ln = rsv_chans[i][1];
                                        clear_bits(off, ln,
                                                edma_cc[j]->edma_unused);
                                }
                        }

                        /* Set the reserved slots in inuse list */
                        rsv_slots = info[j]->rsv->rsv_slots;
                        if (rsv_slots) {
                                for (i = 0; rsv_slots[i][0] != -1; i++) {
                                        off = rsv_slots[i][0];
                                        ln = rsv_slots[i][1];
                                        set_bits(off, ln,
                                                edma_cc[j]->edma_inuse);
                                }
                        }
                }

                sprintf(irq_name, "edma%d", j);
                irq[j] = platform_get_irq_byname(pdev, irq_name);
                edma_cc[j]->irq_res_start = irq[j];
                status = request_irq(irq[j], dma_irq_handler, 0, "edma",
                                        &pdev->dev);
                if (status < 0) {
                        dev_dbg(&pdev->dev, "request_irq %d failed --> %d\n",
                                irq[j], status);
                        goto fail;
                }

                sprintf(irq_name, "edma%d_err", j);
                err_irq[j] = platform_get_irq_byname(pdev, irq_name);
                edma_cc[j]->irq_res_end = err_irq[j];
                status = request_irq(err_irq[j], dma_ccerr_handler, 0,
                                        "edma_error", &pdev->dev);
                if (status < 0) {
                        dev_dbg(&pdev->dev, "request_irq %d failed --> %d\n",
                                err_irq[j], status);
                        goto fail;
                }

                /* Everything lives on transfer controller 1 until otherwise
                 * specified. This way, long transfers on the low priority queue
                 * started by the codec engine will not cause audio defects.
                 */
                for (i = 0; i < edma_cc[j]->num_channels; i++)
                        map_dmach_queue(j, i, EVENTQ_1);

                queue_tc_mapping = info[j]->queue_tc_mapping;
                queue_priority_mapping = info[j]->queue_priority_mapping;

                /* Event queue to TC mapping */
                for (i = 0; queue_tc_mapping[i][0] != -1; i++)
                        map_queue_tc(j, queue_tc_mapping[i][0],
                                        queue_tc_mapping[i][1]);

                /* Event queue priority mapping */
                for (i = 0; queue_priority_mapping[i][0] != -1; i++)
                        assign_priority_to_queue(j,
                                                queue_priority_mapping[i][0],
                                                queue_priority_mapping[i][1]);

                /* Map the channel to param entry if channel mapping logic
                 * exist
                 */
                if (edma_read(j, EDMA_CCCFG) & CHMAP_EXIST)
                        map_dmach_param(j);

                for (i = 0; i < info[j]->n_region; i++) {
                        edma_write_array2(j, EDMA_DRAE, i, 0, 0x0);
                        edma_write_array2(j, EDMA_DRAE, i, 1, 0x0);
                        edma_write_array(j, EDMA_QRAE, i, 0x0);
                }
                arch_num_cc++;
        }

        if (tc_errs_handled) {
                status = request_irq(IRQ_TCERRINT0, dma_tc0err_handler, 0,
                                        "edma_tc0", &pdev->dev);
                if (status < 0) {
                        dev_dbg(&pdev->dev, "request_irq %d failed --> %d\n",
                                IRQ_TCERRINT0, status);
                        return status;
                }
                status = request_irq(IRQ_TCERRINT, dma_tc1err_handler, 0,
                                        "edma_tc1", &pdev->dev);
                if (status < 0) {
                        dev_dbg(&pdev->dev, "request_irq %d --> %d\n",
                                IRQ_TCERRINT, status);
                        return status;
                }
        }

        return 0;

fail:
        for (i = 0; i < EDMA_MAX_CC; i++) {
                if (err_irq[i])
                        free_irq(err_irq[i], &pdev->dev);
                if (irq[i])
                        free_irq(irq[i], &pdev->dev);
        }
fail1:
        for (i = 0; i < EDMA_MAX_CC; i++) {
                if (r[i])
                        release_mem_region(r[i]->start, len[i]);
                if (edmacc_regs_base[i])
                        iounmap(edmacc_regs_base[i]);
                kfree(edma_cc[i]);
        }
        return status;
}


static struct platform_driver edma_driver = {
        .driver.name    = "edma",
};

static int __init edma_init(void)
{
        return platform_driver_probe(&edma_driver, edma_probe);
}
arch_initcall(edma_init);