/*
 *
 *   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

/*
 * 2002-07 Benny Sjostrand benny@hostmobility.com
 */


#include <linux/io.h>
#include <linux/delay.h>
#include <linux/pm.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/mutex.h>

#include <sound/core.h>
#include <sound/control.h>
#include <sound/info.h>
#include "cs46xx.h"

#include "cs46xx_lib.h"
#include "dsp_spos.h"

struct proc_scb_info {
        struct dsp_scb_descriptor * scb_desc;
        struct snd_cs46xx *chip;
};

static void remove_symbol (struct snd_cs46xx * chip, struct dsp_symbol_entry * symbol)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;
        int symbol_index = (int)(symbol - ins->symbol_table.symbols);

        if (snd_BUG_ON(ins->symbol_table.nsymbols <= 0))
                return;
        if (snd_BUG_ON(symbol_index < 0 ||
                       symbol_index >= ins->symbol_table.nsymbols))
                return;

        ins->symbol_table.symbols[symbol_index].deleted = 1;

        if (symbol_index < ins->symbol_table.highest_frag_index) {
                ins->symbol_table.highest_frag_index = symbol_index;
        }
  
        if (symbol_index == ins->symbol_table.nsymbols - 1)
                ins->symbol_table.nsymbols --;

        if (ins->symbol_table.highest_frag_index > ins->symbol_table.nsymbols) {
                ins->symbol_table.highest_frag_index = ins->symbol_table.nsymbols;
        }

}

#ifdef CONFIG_SND_PROC_FS
static void cs46xx_dsp_proc_scb_info_read (struct snd_info_entry *entry,
                                           struct snd_info_buffer *buffer)
{
        struct proc_scb_info * scb_info  = entry->private_data;
        struct dsp_scb_descriptor * scb = scb_info->scb_desc;
        struct dsp_spos_instance * ins;
        struct snd_cs46xx *chip = scb_info->chip;
        int j,col;
        void __iomem *dst = chip->region.idx[1].remap_addr + DSP_PARAMETER_BYTE_OFFSET;

        ins = chip->dsp_spos_instance;

        mutex_lock(&chip->spos_mutex);
        snd_iprintf(buffer,"%04x %s:\n",scb->address,scb->scb_name);

        for (col = 0,j = 0;j < 0x10; j++,col++) {
                if (col == 4) {
                        snd_iprintf(buffer,"\n");
                        col = 0;
                }
                snd_iprintf(buffer,"%08x ",readl(dst + (scb->address + j) * sizeof(u32)));
        }
  
        snd_iprintf(buffer,"\n");

        if (scb->parent_scb_ptr != NULL) {
                snd_iprintf(buffer,"parent [%s:%04x] ", 
                            scb->parent_scb_ptr->scb_name,
                            scb->parent_scb_ptr->address);
        } else snd_iprintf(buffer,"parent [none] ");
  
        snd_iprintf(buffer,"sub_list_ptr [%s:%04x]\nnext_scb_ptr [%s:%04x]  task_entry [%s:%04x]\n",
                    scb->sub_list_ptr->scb_name,
                    scb->sub_list_ptr->address,
                    scb->next_scb_ptr->scb_name,
                    scb->next_scb_ptr->address,
                    scb->task_entry->symbol_name,
                    scb->task_entry->address);

        snd_iprintf(buffer,"index [%d] ref_count [%d]\n",scb->index,scb->ref_count);  
        mutex_unlock(&chip->spos_mutex);
}
#endif

static void _dsp_unlink_scb (struct snd_cs46xx *chip, struct dsp_scb_descriptor * scb)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;

        if ( scb->parent_scb_ptr ) {
                /* unlink parent SCB */
                if (snd_BUG_ON(scb->parent_scb_ptr->sub_list_ptr != scb &&
                               scb->parent_scb_ptr->next_scb_ptr != scb))
                        return;
  
                if (scb->parent_scb_ptr->sub_list_ptr == scb) {

                        if (scb->next_scb_ptr == ins->the_null_scb) {
                                /* last and only node in parent sublist */
                                scb->parent_scb_ptr->sub_list_ptr = scb->sub_list_ptr;

                                if (scb->sub_list_ptr != ins->the_null_scb) {
                                        scb->sub_list_ptr->parent_scb_ptr = scb->parent_scb_ptr;
                                }
                                scb->sub_list_ptr = ins->the_null_scb;
                        } else {
                                /* first node in parent sublist */
                                scb->parent_scb_ptr->sub_list_ptr = scb->next_scb_ptr;

                                if (scb->next_scb_ptr != ins->the_null_scb) {
                                        /* update next node parent ptr. */
                                        scb->next_scb_ptr->parent_scb_ptr = scb->parent_scb_ptr;
                                }
                                scb->next_scb_ptr = ins->the_null_scb;
                        }
                } else {
                        scb->parent_scb_ptr->next_scb_ptr = scb->next_scb_ptr;

                        if (scb->next_scb_ptr != ins->the_null_scb) {
                                /* update next node parent ptr. */
                                scb->next_scb_ptr->parent_scb_ptr = scb->parent_scb_ptr;
                        }
                        scb->next_scb_ptr = ins->the_null_scb;
                }

                /* update parent first entry in DSP RAM */
                cs46xx_dsp_spos_update_scb(chip,scb->parent_scb_ptr);

                /* then update entry in DSP RAM */
                cs46xx_dsp_spos_update_scb(chip,scb);

                scb->parent_scb_ptr = NULL;
        }
}

static void _dsp_clear_sample_buffer (struct snd_cs46xx *chip, u32 sample_buffer_addr,
                                      int dword_count) 
{
        void __iomem *dst = chip->region.idx[2].remap_addr + sample_buffer_addr;
        int i;
  
        for (i = 0; i < dword_count ; ++i ) {
                writel(0, dst);
                dst += 4;
        }  
}

void cs46xx_dsp_remove_scb (struct snd_cs46xx *chip, struct dsp_scb_descriptor * scb)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;
        unsigned long flags;

        /* check integrety */
        if (snd_BUG_ON(scb->index < 0 ||
                       scb->index >= ins->nscb ||
                       (ins->scbs + scb->index) != scb))
                return;

#if 0
        /* can't remove a SCB with childs before 
           removing childs first  */
        if (snd_BUG_ON(scb->sub_list_ptr != ins->the_null_scb ||
                       scb->next_scb_ptr != ins->the_null_scb))
                goto _end;
#endif

        spin_lock_irqsave(&chip->reg_lock, flags);    
        _dsp_unlink_scb (chip,scb);
        spin_unlock_irqrestore(&chip->reg_lock, flags);

        cs46xx_dsp_proc_free_scb_desc(scb);
        if (snd_BUG_ON(!scb->scb_symbol))
                return;
        remove_symbol (chip,scb->scb_symbol);

        ins->scbs[scb->index].deleted = 1;
#ifdef CONFIG_PM_SLEEP
        kfree(ins->scbs[scb->index].data);
        ins->scbs[scb->index].data = NULL;
#endif

        if (scb->index < ins->scb_highest_frag_index)
                ins->scb_highest_frag_index = scb->index;

        if (scb->index == ins->nscb - 1) {
                ins->nscb --;
        }

        if (ins->scb_highest_frag_index > ins->nscb) {
                ins->scb_highest_frag_index = ins->nscb;
        }

#if 0
        /* !!!! THIS IS A PIECE OF SHIT MADE BY ME !!! */
        for(i = scb->index + 1;i < ins->nscb; ++i) {
                ins->scbs[i - 1].index = i - 1;
        }
#endif
}


#ifdef CONFIG_SND_PROC_FS
void cs46xx_dsp_proc_free_scb_desc (struct dsp_scb_descriptor * scb)
{
        if (scb->proc_info) {
                struct proc_scb_info * scb_info = scb->proc_info->private_data;
                struct snd_cs46xx *chip = scb_info->chip;

                dev_dbg(chip->card->dev,
                        "cs46xx_dsp_proc_free_scb_desc: freeing %s\n",
                        scb->scb_name);

                snd_info_free_entry(scb->proc_info);
                scb->proc_info = NULL;

                kfree (scb_info);
        }
}

void cs46xx_dsp_proc_register_scb_desc (struct snd_cs46xx *chip,
                                        struct dsp_scb_descriptor * scb)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;
        struct snd_info_entry * entry;
        struct proc_scb_info * scb_info;

        /* register to proc */
        if (ins->snd_card != NULL && ins->proc_dsp_dir != NULL &&
            scb->proc_info == NULL) {
  
                if ((entry = snd_info_create_card_entry(ins->snd_card, scb->scb_name, 
                                                        ins->proc_dsp_dir)) != NULL) {
                        scb_info = kmalloc(sizeof(struct proc_scb_info), GFP_KERNEL);
                        if (!scb_info) {
                                snd_info_free_entry(entry);
                                entry = NULL;
                                goto out;
                        }

                        scb_info->chip = chip;
                        scb_info->scb_desc = scb;
      
                        entry->content = SNDRV_INFO_CONTENT_TEXT;
                        entry->private_data = scb_info;
                        entry->mode = S_IFREG | S_IRUGO | S_IWUSR;
      
                        entry->c.text.read = cs46xx_dsp_proc_scb_info_read;
      
                        if (snd_info_register(entry) < 0) {
                                snd_info_free_entry(entry);
                                kfree (scb_info);
                                entry = NULL;
                        }
                }
out:
                scb->proc_info = entry;
        }
}
#endif /* CONFIG_SND_PROC_FS */

static struct dsp_scb_descriptor * 
_dsp_create_generic_scb (struct snd_cs46xx *chip, char * name, u32 * scb_data, u32 dest,
                         struct dsp_symbol_entry * task_entry,
                         struct dsp_scb_descriptor * parent_scb,
                         int scb_child_type)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;
        struct dsp_scb_descriptor * scb;
  
        unsigned long flags;

        if (snd_BUG_ON(!ins->the_null_scb))
                return NULL;

        /* fill the data that will be wroten to DSP */
        scb_data[SCBsubListPtr] = 
                (ins->the_null_scb->address << 0x10) | ins->the_null_scb->address;

        scb_data[SCBfuncEntryPtr] &= 0xFFFF0000;
        scb_data[SCBfuncEntryPtr] |= task_entry->address;

        dev_dbg(chip->card->dev, "dsp_spos: creating SCB <%s>\n", name);

        scb = cs46xx_dsp_create_scb(chip,name,scb_data,dest);


        scb->sub_list_ptr = ins->the_null_scb;
        scb->next_scb_ptr = ins->the_null_scb;

        scb->parent_scb_ptr = parent_scb;
        scb->task_entry = task_entry;

  
        /* update parent SCB */
        if (scb->parent_scb_ptr) {
#if 0
                dev_dbg(chip->card->dev,
                        "scb->parent_scb_ptr = %s\n",
                        scb->parent_scb_ptr->scb_name);
                dev_dbg(chip->card->dev,
                        "scb->parent_scb_ptr->next_scb_ptr = %s\n",
                        scb->parent_scb_ptr->next_scb_ptr->scb_name);
                dev_dbg(chip->card->dev,
                        "scb->parent_scb_ptr->sub_list_ptr = %s\n",
                        scb->parent_scb_ptr->sub_list_ptr->scb_name);
#endif
                /* link to  parent SCB */
                if (scb_child_type == SCB_ON_PARENT_NEXT_SCB) {
                        if (snd_BUG_ON(scb->parent_scb_ptr->next_scb_ptr !=
                                       ins->the_null_scb))
                                return NULL;

                        scb->parent_scb_ptr->next_scb_ptr = scb;

                } else if (scb_child_type == SCB_ON_PARENT_SUBLIST_SCB) {
                        if (snd_BUG_ON(scb->parent_scb_ptr->sub_list_ptr !=
                                       ins->the_null_scb))
                                return NULL;

                        scb->parent_scb_ptr->sub_list_ptr = scb;
                } else {
                        snd_BUG();
                }

                spin_lock_irqsave(&chip->reg_lock, flags);

                /* update entry in DSP RAM */
                cs46xx_dsp_spos_update_scb(chip,scb->parent_scb_ptr);

                spin_unlock_irqrestore(&chip->reg_lock, flags);
        }


        cs46xx_dsp_proc_register_scb_desc (chip,scb);

        return scb;
}

static struct dsp_scb_descriptor * 
cs46xx_dsp_create_generic_scb (struct snd_cs46xx *chip, char * name, u32 * scb_data,
                               u32 dest, char * task_entry_name,
                               struct dsp_scb_descriptor * parent_scb,
                               int scb_child_type)
{
        struct dsp_symbol_entry * task_entry;

        task_entry = cs46xx_dsp_lookup_symbol (chip,task_entry_name,
                                               SYMBOL_CODE);
  
        if (task_entry == NULL) {
                dev_err(chip->card->dev,
                        "dsp_spos: symbol %s not found\n", task_entry_name);
                return NULL;
        }
  
        return _dsp_create_generic_scb (chip,name,scb_data,dest,task_entry,
                                        parent_scb,scb_child_type);
}

struct dsp_scb_descriptor * 
cs46xx_dsp_create_timing_master_scb (struct snd_cs46xx *chip)
{
        struct dsp_scb_descriptor * scb;
  
        struct dsp_timing_master_scb timing_master_scb = {
                { 0,
                  0,
                  0,
                  0
                },
                { 0,
                  0,
                  0,
                  0,
                  0
                },
                0,0,
                0,NULL_SCB_ADDR,
                0,0,             /* extraSampleAccum:TMreserved */
                0,0,             /* codecFIFOptr:codecFIFOsyncd */
                0x0001,0x8000,   /* fracSampAccumQm1:TMfrmsLeftInGroup */
                0x0001,0x0000,   /* fracSampCorrectionQm1:TMfrmGroupLength */
                0x00060000       /* nSampPerFrmQ15 */
        };    
  
        scb = cs46xx_dsp_create_generic_scb(chip,"TimingMasterSCBInst",(u32 *)&timing_master_scb,
                                            TIMINGMASTER_SCB_ADDR,
                                            "TIMINGMASTER",NULL,SCB_NO_PARENT);

        return scb;
}


struct dsp_scb_descriptor * 
cs46xx_dsp_create_codec_out_scb(struct snd_cs46xx * chip, char * codec_name,
                                u16 channel_disp, u16 fifo_addr, u16 child_scb_addr,
                                u32 dest, struct dsp_scb_descriptor * parent_scb,
                                int scb_child_type)
{
        struct dsp_scb_descriptor * scb;
  
        struct dsp_codec_output_scb codec_out_scb = {
                { 0,
                  0,
                  0,
                  0
                },
                {
                        0,
                        0,
                        0,
                        0,
                        0
                },
                0,0,
                0,NULL_SCB_ADDR,
                0,                      /* COstrmRsConfig */
                0,                      /* COstrmBufPtr */
                channel_disp,fifo_addr, /* leftChanBaseIOaddr:rightChanIOdisp */
                0x0000,0x0080,          /* (!AC97!) COexpVolChangeRate:COscaleShiftCount */
                0,child_scb_addr        /* COreserved - need child scb to work with rom code */
        };
  
  
        scb = cs46xx_dsp_create_generic_scb(chip,codec_name,(u32 *)&codec_out_scb,
                                            dest,"S16_CODECOUTPUTTASK",parent_scb,
                                            scb_child_type);
  
        return scb;
}

struct dsp_scb_descriptor * 
cs46xx_dsp_create_codec_in_scb(struct snd_cs46xx * chip, char * codec_name,
                               u16 channel_disp, u16 fifo_addr, u16 sample_buffer_addr,
                               u32 dest, struct dsp_scb_descriptor * parent_scb,
                               int scb_child_type)
{

        struct dsp_scb_descriptor * scb;
        struct dsp_codec_input_scb codec_input_scb = {
                { 0,
                  0,
                  0,
                  0
                },
                {
                        0,
                        0,
                        0,
                        0,
                        0
                },
    
#if 0  /* cs4620 */
                SyncIOSCB,NULL_SCB_ADDR
#else
                0 , 0,
#endif
                0,0,

                RSCONFIG_SAMPLE_16STEREO + RSCONFIG_MODULO_64,  /* strmRsConfig */
                sample_buffer_addr << 0x10,       /* strmBufPtr; defined as a dword ptr, used as a byte ptr */
                channel_disp,fifo_addr,           /* (!AC97!) leftChanBaseINaddr=AC97primary 
                                                     link input slot 3 :rightChanINdisp=""slot 4 */
                0x0000,0x0000,                    /* (!AC97!) ????:scaleShiftCount; no shift needed 
                                                     because AC97 is already 20 bits */
                0x80008000                        /* ??clw cwcgame.scb has 0 */
        };
  
        scb = cs46xx_dsp_create_generic_scb(chip,codec_name,(u32 *)&codec_input_scb,
                                            dest,"S16_CODECINPUTTASK",parent_scb,
                                            scb_child_type);
        return scb;
}


static struct dsp_scb_descriptor * 
cs46xx_dsp_create_pcm_reader_scb(struct snd_cs46xx * chip, char * scb_name,
                                 u16 sample_buffer_addr, u32 dest,
                                 int virtual_channel, u32 playback_hw_addr,
                                 struct dsp_scb_descriptor * parent_scb,
                                 int scb_child_type)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;
        struct dsp_scb_descriptor * scb;
  
        struct dsp_generic_scb pcm_reader_scb = {
    
                /*
                  Play DMA Task xfers data from host buffer to SP buffer
                  init/runtime variables:
                  PlayAC: Play Audio Data Conversion - SCB loc: 2nd dword, mask: 0x0000F000L
                  DATA_FMT_16BIT_ST_LTLEND(0x00000000L)   from 16-bit stereo, little-endian
                  DATA_FMT_8_BIT_ST_SIGNED(0x00001000L)   from 8-bit stereo, signed
                  DATA_FMT_16BIT_MN_LTLEND(0x00002000L)   from 16-bit mono, little-endian
                  DATA_FMT_8_BIT_MN_SIGNED(0x00003000L)   from 8-bit mono, signed
                  DATA_FMT_16BIT_ST_BIGEND(0x00004000L)   from 16-bit stereo, big-endian
                  DATA_FMT_16BIT_MN_BIGEND(0x00006000L)   from 16-bit mono, big-endian
                  DATA_FMT_8_BIT_ST_UNSIGNED(0x00009000L) from 8-bit stereo, unsigned
                  DATA_FMT_8_BIT_MN_UNSIGNED(0x0000b000L) from 8-bit mono, unsigned
                  ? Other combinations possible from:
                  DMA_RQ_C2_AUDIO_CONVERT_MASK    0x0000F000L
                  DMA_RQ_C2_AC_NONE               0x00000000L
                  DMA_RQ_C2_AC_8_TO_16_BIT        0x00001000L
                  DMA_RQ_C2_AC_MONO_TO_STEREO     0x00002000L
                  DMA_RQ_C2_AC_ENDIAN_CONVERT     0x00004000L
                  DMA_RQ_C2_AC_SIGNED_CONVERT     0x00008000L
        
                  HostBuffAddr: Host Buffer Physical Byte Address - SCB loc:3rd dword, Mask: 0xFFFFFFFFL
                  aligned to dword boundary
                */
                /* Basic (non scatter/gather) DMA requestor (4 ints) */
                { DMA_RQ_C1_SOURCE_ON_HOST +        /* source buffer is on the host */
                  DMA_RQ_C1_SOURCE_MOD1024 +        /* source buffer is 1024 dwords (4096 bytes) */
                  DMA_RQ_C1_DEST_MOD32 +            /* dest buffer(PCMreaderBuf) is 32 dwords*/
                  DMA_RQ_C1_WRITEBACK_SRC_FLAG +    /* ?? */
                  DMA_RQ_C1_WRITEBACK_DEST_FLAG +   /* ?? */
                  15,                             /* DwordCount-1: picked 16 for DwordCount because Jim */
                  /*        Barnette said that is what we should use since */
                  /*        we are not running in optimized mode? */
                  DMA_RQ_C2_AC_NONE +
                  DMA_RQ_C2_SIGNAL_SOURCE_PINGPONG + /* set play interrupt (bit0) in HISR when source */
                  /*   buffer (on host) crosses half-way point */
                  virtual_channel,                   /* Play DMA channel arbitrarily set to 0 */
                  playback_hw_addr,                  /* HostBuffAddr (source) */
                  DMA_RQ_SD_SP_SAMPLE_ADDR +         /* destination buffer is in SP Sample Memory */
                  sample_buffer_addr                 /* SP Buffer Address (destination) */
                },
                /* Scatter/gather DMA requestor extension   (5 ints) */
                {
                        0,
                        0,
                        0,
                        0,
                        0 
                },
                /* Sublist pointer & next stream control block (SCB) link. */
                NULL_SCB_ADDR,NULL_SCB_ADDR,
                /* Pointer to this tasks parameter block & stream function pointer */
                0,NULL_SCB_ADDR,
                /* rsConfig register for stream buffer (rsDMA reg. is loaded from basicReq.daw */
                /*   for incoming streams, or basicReq.saw, for outgoing streams) */
                RSCONFIG_DMA_ENABLE +                 /* enable DMA */
                (19 << RSCONFIG_MAX_DMA_SIZE_SHIFT) + /* MAX_DMA_SIZE picked to be 19 since SPUD  */
                /*  uses it for some reason */
                ((dest >> 4) << RSCONFIG_STREAM_NUM_SHIFT) + /* stream number = SCBaddr/16 */
                RSCONFIG_SAMPLE_16STEREO +
                RSCONFIG_MODULO_32,             /* dest buffer(PCMreaderBuf) is 32 dwords (256 bytes) */
                /* Stream sample pointer & MAC-unit mode for this stream */
                (sample_buffer_addr << 0x10),
                /* Fractional increment per output sample in the input sample buffer */
                0, 
                {
                        /* Standard stereo volume control
                           default muted */
                        0xffff,0xffff,
                        0xffff,0xffff
                }
        };

        if (ins->null_algorithm == NULL) {
                ins->null_algorithm =  cs46xx_dsp_lookup_symbol (chip,"NULLALGORITHM",
                                                                 SYMBOL_CODE);
    
                if (ins->null_algorithm == NULL) {
                        dev_err(chip->card->dev,
                                "dsp_spos: symbol NULLALGORITHM not found\n");
                        return NULL;
                }    
        }

        scb = _dsp_create_generic_scb(chip,scb_name,(u32 *)&pcm_reader_scb,
                                      dest,ins->null_algorithm,parent_scb,
                                      scb_child_type);
  
        return scb;
}

#define GOF_PER_SEC 200

struct dsp_scb_descriptor * 
cs46xx_dsp_create_src_task_scb(struct snd_cs46xx * chip, char * scb_name,
                               int rate,
                               u16 src_buffer_addr,
                               u16 src_delay_buffer_addr, u32 dest,
                               struct dsp_scb_descriptor * parent_scb,
                               int scb_child_type,
                               int pass_through)
{

        struct dsp_spos_instance * ins = chip->dsp_spos_instance;
        struct dsp_scb_descriptor * scb;
        unsigned int tmp1, tmp2;
        unsigned int phiIncr;
        unsigned int correctionPerGOF, correctionPerSec;

        dev_dbg(chip->card->dev, "dsp_spos: setting %s rate to %u\n",
                scb_name, rate);

        /*
         *  Compute the values used to drive the actual sample rate conversion.
         *  The following formulas are being computed, using inline assembly
         *  since we need to use 64 bit arithmetic to compute the values:
         *
         *  phiIncr = floor((Fs,in * 2^26) / Fs,out)
         *  correctionPerGOF = floor((Fs,in * 2^26 - Fs,out * phiIncr) /
         *                                   GOF_PER_SEC)
         *  ulCorrectionPerSec = Fs,in * 2^26 - Fs,out * phiIncr -M
         *                       GOF_PER_SEC * correctionPerGOF
         *
         *  i.e.
         *
         *  phiIncr:other = dividend:remainder((Fs,in * 2^26) / Fs,out)
         *  correctionPerGOF:correctionPerSec =
         *      dividend:remainder(ulOther / GOF_PER_SEC)
         */
        tmp1 = rate << 16;
        phiIncr = tmp1 / 48000;
        tmp1 -= phiIncr * 48000;
        tmp1 <<= 10;
        phiIncr <<= 10;
        tmp2 = tmp1 / 48000;
        phiIncr += tmp2;
        tmp1 -= tmp2 * 48000;
        correctionPerGOF = tmp1 / GOF_PER_SEC;
        tmp1 -= correctionPerGOF * GOF_PER_SEC;
        correctionPerSec = tmp1;

        {
                struct dsp_src_task_scb src_task_scb = {
                        0x0028,0x00c8,
                        0x5555,0x0000,
                        0x0000,0x0000,
                        src_buffer_addr,1,
                        correctionPerGOF,correctionPerSec,
                        RSCONFIG_SAMPLE_16STEREO + RSCONFIG_MODULO_32,  
                        0x0000,src_delay_buffer_addr,                  
                        0x0,                                            
                        0x080,(src_delay_buffer_addr + (24 * 4)),
                        0,0, /* next_scb, sub_list_ptr */
                        0,0, /* entry, this_spb */
                        RSCONFIG_SAMPLE_16STEREO + RSCONFIG_MODULO_8,
                        src_buffer_addr << 0x10,
                        phiIncr,
                        { 
                                0xffff - ins->dac_volume_right,0xffff - ins->dac_volume_left,
                                0xffff - ins->dac_volume_right,0xffff - ins->dac_volume_left
                        }
                };
                
                if (ins->s16_up == NULL) {
                        ins->s16_up =  cs46xx_dsp_lookup_symbol (chip,"S16_UPSRC",
                                                                 SYMBOL_CODE);
                        
                        if (ins->s16_up == NULL) {
                                dev_err(chip->card->dev,
                                        "dsp_spos: symbol S16_UPSRC not found\n");
                                return NULL;
                        }    
                }
                
                /* clear buffers */
                _dsp_clear_sample_buffer (chip,src_buffer_addr,8);
                _dsp_clear_sample_buffer (chip,src_delay_buffer_addr,32);
                                
                if (pass_through) {
                        /* wont work with any other rate than
                           the native DSP rate */
                        snd_BUG_ON(rate != 48000);

                        scb = cs46xx_dsp_create_generic_scb(chip,scb_name,(u32 *)&src_task_scb,
                                                            dest,"DMAREADER",parent_scb,
                                                            scb_child_type);
                } else {
                        scb = _dsp_create_generic_scb(chip,scb_name,(u32 *)&src_task_scb,
                                                      dest,ins->s16_up,parent_scb,
                                                      scb_child_type);
                }


        }

        return scb;
}

#if 0 /* not used */
struct dsp_scb_descriptor * 
cs46xx_dsp_create_filter_scb(struct snd_cs46xx * chip, char * scb_name,
                             u16 buffer_addr, u32 dest,
                             struct dsp_scb_descriptor * parent_scb,
                             int scb_child_type) {
        struct dsp_scb_descriptor * scb;
        
        struct dsp_filter_scb filter_scb = {
                .a0_right            = 0x41a9,
                .a0_left             = 0x41a9,
                .a1_right            = 0xb8e4,
                .a1_left             = 0xb8e4,
                .a2_right            = 0x3e55,
                .a2_left             = 0x3e55,
                
                .filter_unused3      = 0x0000,
                .filter_unused2      = 0x0000,

                .output_buf_ptr      = buffer_addr,
                .init                = 0x000,

                .prev_sample_output1 = 0x00000000,
                .prev_sample_output2 = 0x00000000,

                .prev_sample_input1  = 0x00000000,
                .prev_sample_input2  = 0x00000000,

                .next_scb_ptr        = 0x0000,
                .sub_list_ptr        = 0x0000,

                .entry_point         = 0x0000,
                .spb_ptr             = 0x0000,

                .b0_right            = 0x0e38,
                .b0_left             = 0x0e38,
                .b1_right            = 0x1c71,
                .b1_left             = 0x1c71,
                .b2_right            = 0x0e38,
                .b2_left             = 0x0e38,
        };


        scb = cs46xx_dsp_create_generic_scb(chip,scb_name,(u32 *)&filter_scb,
                                            dest,"FILTERTASK",parent_scb,
                                            scb_child_type);

        return scb;
}
#endif /* not used */

struct dsp_scb_descriptor * 
cs46xx_dsp_create_mix_only_scb(struct snd_cs46xx * chip, char * scb_name,
                               u16 mix_buffer_addr, u32 dest,
                               struct dsp_scb_descriptor * parent_scb,
                               int scb_child_type)
{
        struct dsp_scb_descriptor * scb;
  
        struct dsp_mix_only_scb master_mix_scb = {
                /* 0 */ { 0,
                          /* 1 */   0,
                          /* 2 */  mix_buffer_addr,
                          /* 3 */  0
                          /*   */ },
                {
                        /* 4 */  0,
                        /* 5 */  0,
                        /* 6 */  0,
                        /* 7 */  0,
                        /* 8 */  0x00000080
                },
                /* 9 */ 0,0,
                /* A */ 0,0,
                /* B */ RSCONFIG_SAMPLE_16STEREO + RSCONFIG_MODULO_32,
                /* C */ (mix_buffer_addr  + (16 * 4)) << 0x10, 
                /* D */ 0,
                {
                        /* E */ 0x8000,0x8000,
                        /* F */ 0x8000,0x8000
                }
        };


        scb = cs46xx_dsp_create_generic_scb(chip,scb_name,(u32 *)&master_mix_scb,
                                            dest,"S16_MIX",parent_scb,
                                            scb_child_type);
        return scb;
}


struct dsp_scb_descriptor * 
cs46xx_dsp_create_mix_to_ostream_scb(struct snd_cs46xx * chip, char * scb_name,
                                     u16 mix_buffer_addr, u16 writeback_spb, u32 dest,
                                     struct dsp_scb_descriptor * parent_scb,
                                     int scb_child_type)
{
        struct dsp_scb_descriptor * scb;

        struct dsp_mix2_ostream_scb mix2_ostream_scb = {
                /* Basic (non scatter/gather) DMA requestor (4 ints) */
                { 
                        DMA_RQ_C1_SOURCE_MOD64 +
                        DMA_RQ_C1_DEST_ON_HOST +
                        DMA_RQ_C1_DEST_MOD1024 +
                        DMA_RQ_C1_WRITEBACK_SRC_FLAG + 
                        DMA_RQ_C1_WRITEBACK_DEST_FLAG +
                        15,                            
      
                        DMA_RQ_C2_AC_NONE +
                        DMA_RQ_C2_SIGNAL_DEST_PINGPONG + 
      
                        CS46XX_DSP_CAPTURE_CHANNEL,                                 
                        DMA_RQ_SD_SP_SAMPLE_ADDR + 
                        mix_buffer_addr, 
                        0x0                   
                },
    
                { 0, 0, 0, 0, 0, },
                0,0,
                0,writeback_spb,
    
                RSCONFIG_DMA_ENABLE + 
                (19 << RSCONFIG_MAX_DMA_SIZE_SHIFT) + 
    
                ((dest >> 4) << RSCONFIG_STREAM_NUM_SHIFT) +
                RSCONFIG_DMA_TO_HOST + 
                RSCONFIG_SAMPLE_16STEREO +
                RSCONFIG_MODULO_64,    
                (mix_buffer_addr + (32 * 4)) << 0x10,
                1,0,            
                0x0001,0x0080,
                0xFFFF,0
        };


        scb = cs46xx_dsp_create_generic_scb(chip,scb_name,(u32 *)&mix2_ostream_scb,
                                
            dest,"S16_MIX_TO_OSTREAM",parent_scb,
                                            scb_child_type);
  
        return scb;
}


struct dsp_scb_descriptor * 
cs46xx_dsp_create_vari_decimate_scb(struct snd_cs46xx * chip,char * scb_name,
                                    u16 vari_buffer_addr0,
                                    u16 vari_buffer_addr1,
                                    u32 dest,
                                    struct dsp_scb_descriptor * parent_scb,
                                    int scb_child_type)
{

        struct dsp_scb_descriptor * scb;
  
        struct dsp_vari_decimate_scb vari_decimate_scb = {
                0x0028,0x00c8,
                0x5555,0x0000,
                0x0000,0x0000,
                vari_buffer_addr0,vari_buffer_addr1,
    
                0x0028,0x00c8,
                RSCONFIG_SAMPLE_16STEREO + RSCONFIG_MODULO_256, 
    
                0xFF800000,   
                0,
                0x0080,vari_buffer_addr1 + (25 * 4), 
    
                0,0, 
                0,0,

                RSCONFIG_SAMPLE_16STEREO + RSCONFIG_MODULO_8,
                vari_buffer_addr0 << 0x10,   
                0x04000000,                   
                {
                        0x8000,0x8000, 
                        0xFFFF,0xFFFF
                }
        };

        scb = cs46xx_dsp_create_generic_scb(chip,scb_name,(u32 *)&vari_decimate_scb,
                                            dest,"VARIDECIMATE",parent_scb,
                                            scb_child_type);
  
        return scb;
}


static struct dsp_scb_descriptor * 
cs46xx_dsp_create_pcm_serial_input_scb(struct snd_cs46xx * chip, char * scb_name, u32 dest,
                                       struct dsp_scb_descriptor * input_scb,
                                       struct dsp_scb_descriptor * parent_scb,
                                       int scb_child_type)
{

        struct dsp_scb_descriptor * scb;


        struct dsp_pcm_serial_input_scb pcm_serial_input_scb = {
                { 0,
                  0,
                  0,
                  0
                },
                {
                        0,
                        0,
                        0,
                        0,
                        0
                },

                0,0,
                0,0,

                RSCONFIG_SAMPLE_16STEREO + RSCONFIG_MODULO_16,
                0,
      /* 0xD */ 0,input_scb->address,
                {
      /* 0xE */   0x8000,0x8000,
      /* 0xF */   0x8000,0x8000
                }
        };

        scb = cs46xx_dsp_create_generic_scb(chip,scb_name,(u32 *)&pcm_serial_input_scb,
                                            dest,"PCMSERIALINPUTTASK",parent_scb,
                                            scb_child_type);
        return scb;
}


static struct dsp_scb_descriptor * 
cs46xx_dsp_create_asynch_fg_tx_scb(struct snd_cs46xx * chip, char * scb_name, u32 dest,
                                   u16 hfg_scb_address,
                                   u16 asynch_buffer_address,
                                   struct dsp_scb_descriptor * parent_scb,
                                   int scb_child_type)
{

        struct dsp_scb_descriptor * scb;

        struct dsp_asynch_fg_tx_scb asynch_fg_tx_scb = {
                0xfc00,0x03ff,      /*  Prototype sample buffer size of 256 dwords */
                0x0058,0x0028,      /* Min Delta 7 dwords == 28 bytes */
                /* : Max delta 25 dwords == 100 bytes */
                0,hfg_scb_address,  /* Point to HFG task SCB */
                0,0,                /* Initialize current Delta and Consumer ptr adjustment count */
                0,                  /* Initialize accumulated Phi to 0 */
                0,0x2aab,           /* Const 1/3 */
    
                {
                        0,         /* Define the unused elements */
                        0,
                        0
                },
    
                0,0,
                0,dest + AFGTxAccumPhi,
    
                RSCONFIG_SAMPLE_16STEREO + RSCONFIG_MODULO_256, /* Stereo, 256 dword */
                (asynch_buffer_address) << 0x10,  /* This should be automagically synchronized
                                                     to the producer pointer */
    
                /* There is no correct initial value, it will depend upon the detected
                   rate etc  */
                0x18000000,                     /* Phi increment for approx 32k operation */
                0x8000,0x8000,                  /* Volume controls are unused at this time */
                0x8000,0x8000
        };
  
        scb = cs46xx_dsp_create_generic_scb(chip,scb_name,(u32 *)&asynch_fg_tx_scb,
                                            dest,"ASYNCHFGTXCODE",parent_scb,
                                            scb_child_type);

        return scb;
}


struct dsp_scb_descriptor * 
cs46xx_dsp_create_asynch_fg_rx_scb(struct snd_cs46xx * chip, char * scb_name, u32 dest,
                                   u16 hfg_scb_address,
                                   u16 asynch_buffer_address,
                                   struct dsp_scb_descriptor * parent_scb,
                                   int scb_child_type)
{

        struct dsp_spos_instance * ins = chip->dsp_spos_instance;
        struct dsp_scb_descriptor * scb;

        struct dsp_asynch_fg_rx_scb asynch_fg_rx_scb = {
                0xfe00,0x01ff,      /*  Prototype sample buffer size of 128 dwords */
                0x0064,0x001c,      /* Min Delta 7 dwords == 28 bytes */
                                    /* : Max delta 25 dwords == 100 bytes */
                0,hfg_scb_address,  /* Point to HFG task SCB */
                0,0,                            /* Initialize current Delta and Consumer ptr adjustment count */
                {
                        0,                /* Define the unused elements */
                        0,
                        0,
                        0,
                        0
                },
      
                0,0,
                0,dest,
    
                RSCONFIG_MODULO_128 |
        RSCONFIG_SAMPLE_16STEREO,                         /* Stereo, 128 dword */
                ( (asynch_buffer_address + (16 * 4))  << 0x10),   /* This should be automagically 
                                                                                          synchrinized to the producer pointer */
    
                /* There is no correct initial value, it will depend upon the detected
                   rate etc  */
                0x18000000,         

                /* Set IEC958 input volume */
                0xffff - ins->spdif_input_volume_right,0xffff - ins->spdif_input_volume_left,
                0xffff - ins->spdif_input_volume_right,0xffff - ins->spdif_input_volume_left,
        };

        scb = cs46xx_dsp_create_generic_scb(chip,scb_name,(u32 *)&asynch_fg_rx_scb,
                                            dest,"ASYNCHFGRXCODE",parent_scb,
                                            scb_child_type);

        return scb;
}


#if 0 /* not used */
struct dsp_scb_descriptor * 
cs46xx_dsp_create_output_snoop_scb(struct snd_cs46xx * chip, char * scb_name, u32 dest,
                                   u16 snoop_buffer_address,
                                   struct dsp_scb_descriptor * snoop_scb,
                                   struct dsp_scb_descriptor * parent_scb,
                                   int scb_child_type)
{

        struct dsp_scb_descriptor * scb;
  
        struct dsp_output_snoop_scb output_snoop_scb = {
                { 0,    /*  not used.  Zero */
                  0,
                  0,
                  0,
                },
                {
                        0, /* not used.  Zero */
                        0,
                        0,
                        0,
                        0
                },
    
                0,0,
                0,0,
    
                RSCONFIG_SAMPLE_16STEREO + RSCONFIG_MODULO_64,
                snoop_buffer_address << 0x10,  
                0,0,
                0,
                0,snoop_scb->address
        };
  
        scb = cs46xx_dsp_create_generic_scb(chip,scb_name,(u32 *)&output_snoop_scb,
                                            dest,"OUTPUTSNOOP",parent_scb,
                                            scb_child_type);
        return scb;
}
#endif /* not used */


struct dsp_scb_descriptor * 
cs46xx_dsp_create_spio_write_scb(struct snd_cs46xx * chip, char * scb_name, u32 dest,
                                 struct dsp_scb_descriptor * parent_scb,
                                 int scb_child_type)
{
        struct dsp_scb_descriptor * scb;
  
        struct dsp_spio_write_scb spio_write_scb = {
                0,0,         /*   SPIOWAddress2:SPIOWAddress1; */
                0,           /*   SPIOWData1; */
                0,           /*   SPIOWData2; */
                0,0,         /*   SPIOWAddress4:SPIOWAddress3; */
                0,           /*   SPIOWData3; */
                0,           /*   SPIOWData4; */
                0,0,         /*   SPIOWDataPtr:Unused1; */
                { 0,0 },     /*   Unused2[2]; */
    
                0,0,         /*   SPIOWChildPtr:SPIOWSiblingPtr; */
                0,0,         /*   SPIOWThisPtr:SPIOWEntryPoint; */
    
                { 
                        0,
                        0,
                        0,
                        0,
                        0          /*   Unused3[5];  */
                }
        };

        scb = cs46xx_dsp_create_generic_scb(chip,scb_name,(u32 *)&spio_write_scb,
                                            dest,"SPIOWRITE",parent_scb,
                                            scb_child_type);

        return scb;
}

struct dsp_scb_descriptor *
cs46xx_dsp_create_magic_snoop_scb(struct snd_cs46xx * chip, char * scb_name, u32 dest,
                                  u16 snoop_buffer_address,
                                  struct dsp_scb_descriptor * snoop_scb,
                                  struct dsp_scb_descriptor * parent_scb,
                                  int scb_child_type)
{
        struct dsp_scb_descriptor * scb;
  
        struct dsp_magic_snoop_task magic_snoop_scb = {
                /* 0 */ 0, /* i0 */
                /* 1 */ 0, /* i1 */
                /* 2 */ snoop_buffer_address << 0x10,
                /* 3 */ 0,snoop_scb->address,
                /* 4 */ 0, /* i3 */
                /* 5 */ 0, /* i4 */
                /* 6 */ 0, /* i5 */
                /* 7 */ 0, /* i6 */
                /* 8 */ 0, /* i7 */
                /* 9 */ 0,0, /* next_scb, sub_list_ptr */
                /* A */ 0,0, /* entry_point, this_ptr */
                /* B */ RSCONFIG_SAMPLE_16STEREO + RSCONFIG_MODULO_64,
                /* C */ snoop_buffer_address  << 0x10,
                /* D */ 0,
                /* E */ { 0x8000,0x8000,
                /* F */   0xffff,0xffff
                }
        };

        scb = cs46xx_dsp_create_generic_scb(chip,scb_name,(u32 *)&magic_snoop_scb,
                                            dest,"MAGICSNOOPTASK",parent_scb,
                                            scb_child_type);

        return scb;
}

static struct dsp_scb_descriptor *
find_next_free_scb (struct snd_cs46xx * chip, struct dsp_scb_descriptor * from)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;
        struct dsp_scb_descriptor * scb = from;

        while (scb->next_scb_ptr != ins->the_null_scb) {
                if (snd_BUG_ON(!scb->next_scb_ptr))
                        return NULL;

                scb = scb->next_scb_ptr;
        }

        return scb;
}

static u32 pcm_reader_buffer_addr[DSP_MAX_PCM_CHANNELS] = {
        0x0600, /* 1 */
        0x1500, /* 2 */
        0x1580, /* 3 */
        0x1600, /* 4 */
        0x1680, /* 5 */
        0x1700, /* 6 */
        0x1780, /* 7 */
        0x1800, /* 8 */
        0x1880, /* 9 */
        0x1900, /* 10 */
        0x1980, /* 11 */
        0x1A00, /* 12 */
        0x1A80, /* 13 */
        0x1B00, /* 14 */
        0x1B80, /* 15 */
        0x1C00, /* 16 */
        0x1C80, /* 17 */
        0x1D00, /* 18 */
        0x1D80, /* 19 */
        0x1E00, /* 20 */
        0x1E80, /* 21 */
        0x1F00, /* 22 */
        0x1F80, /* 23 */
        0x2000, /* 24 */
        0x2080, /* 25 */
        0x2100, /* 26 */
        0x2180, /* 27 */
        0x2200, /* 28 */
        0x2280, /* 29 */
        0x2300, /* 30 */
        0x2380, /* 31 */
        0x2400, /* 32 */
};

static u32 src_output_buffer_addr[DSP_MAX_SRC_NR] = {
        0x2B80,
        0x2BA0,
        0x2BC0,
        0x2BE0,
        0x2D00,  
        0x2D20,  
        0x2D40,  
        0x2D60,
        0x2D80,
        0x2DA0,
        0x2DC0,
        0x2DE0,
        0x2E00,
        0x2E20
};

static u32 src_delay_buffer_addr[DSP_MAX_SRC_NR] = {
        0x2480,
        0x2500,
        0x2580,
        0x2600,
        0x2680,
        0x2700,
        0x2780,
        0x2800,
        0x2880,
        0x2900,
        0x2980,
        0x2A00,
        0x2A80,
        0x2B00
};

struct dsp_pcm_channel_descriptor *
cs46xx_dsp_create_pcm_channel (struct snd_cs46xx * chip,
                               u32 sample_rate, void * private_data, 
                               u32 hw_dma_addr,
                               int pcm_channel_id)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;
        struct dsp_scb_descriptor * src_scb = NULL, * pcm_scb, * mixer_scb = NULL;
        struct dsp_scb_descriptor * src_parent_scb = NULL;

        /* struct dsp_scb_descriptor * pcm_parent_scb; */
        char scb_name[DSP_MAX_SCB_NAME];
        int i, pcm_index = -1, insert_point, src_index = -1, pass_through = 0;
        unsigned long flags;

        switch (pcm_channel_id) {
        case DSP_PCM_MAIN_CHANNEL:
                mixer_scb = ins->master_mix_scb;
                break;
        case DSP_PCM_REAR_CHANNEL:
                mixer_scb = ins->rear_mix_scb;
                break;
        case DSP_PCM_CENTER_LFE_CHANNEL:
                mixer_scb = ins->center_lfe_mix_scb;
                break;
        case DSP_PCM_S71_CHANNEL:
                /* TODO */
                snd_BUG();
                break;
        case DSP_IEC958_CHANNEL:
                if (snd_BUG_ON(!ins->asynch_tx_scb))
                        return NULL;
                mixer_scb = ins->asynch_tx_scb;

                /* if sample rate is set to 48khz we pass
                   the Sample Rate Converted (which could
                   alter the raw data stream ...) */
                if (sample_rate == 48000) {
                        dev_dbg(chip->card->dev, "IEC958 pass through\n");
                        /* Hack to bypass creating a new SRC */
                        pass_through = 1;
                }
                break;
        default:
                snd_BUG();
                return NULL;
        }
        /* default sample rate is 44100 */
        if (!sample_rate) sample_rate = 44100;

        /* search for a already created SRC SCB with the same sample rate */
        for (i = 0; i < DSP_MAX_PCM_CHANNELS && 
                     (pcm_index == -1 || src_scb == NULL); ++i) {

                /* virtual channel reserved 
                   for capture */
                if (i == CS46XX_DSP_CAPTURE_CHANNEL) continue;

                if (ins->pcm_channels[i].active) {
                        if (!src_scb && 
                            ins->pcm_channels[i].sample_rate == sample_rate &&
                            ins->pcm_channels[i].mixer_scb == mixer_scb) {
                                src_scb = ins->pcm_channels[i].src_scb;
                                ins->pcm_channels[i].src_scb->ref_count ++;
                                src_index = ins->pcm_channels[i].src_slot;
                        }
                } else if (pcm_index == -1) {
                        pcm_index = i;
                }
        }

        if (pcm_index == -1) {
                dev_err(chip->card->dev, "dsp_spos: no free PCM channel\n");
                return NULL;
        }

        if (src_scb == NULL) {
                if (ins->nsrc_scb >= DSP_MAX_SRC_NR) {
                        dev_err(chip->card->dev,
                                "dsp_spos: to many SRC instances\n!");
                        return NULL;
                }

                /* find a free slot */
                for (i = 0; i < DSP_MAX_SRC_NR; ++i) {
                        if (ins->src_scb_slots[i] == 0) {
                                src_index = i;
                                ins->src_scb_slots[i] = 1;
                                break;
                        }
                }
                if (snd_BUG_ON(src_index == -1))
                        return NULL;

                /* we need to create a new SRC SCB */
                if (mixer_scb->sub_list_ptr == ins->the_null_scb) {
                        src_parent_scb = mixer_scb;
                        insert_point = SCB_ON_PARENT_SUBLIST_SCB;
                } else {
                        src_parent_scb = find_next_free_scb(chip,mixer_scb->sub_list_ptr);
                        insert_point = SCB_ON_PARENT_NEXT_SCB;
                }

                snprintf (scb_name,DSP_MAX_SCB_NAME,"SrcTask_SCB%d",src_index);
                
                dev_dbg(chip->card->dev,
                        "dsp_spos: creating SRC \"%s\"\n", scb_name);
                src_scb = cs46xx_dsp_create_src_task_scb(chip,scb_name,
                                                         sample_rate,
                                                         src_output_buffer_addr[src_index],
                                                         src_delay_buffer_addr[src_index],
                                                         /* 0x400 - 0x600 source SCBs */
                                                         0x400 + (src_index * 0x10) ,
                                                         src_parent_scb,
                                                         insert_point,
                                                         pass_through);

                if (!src_scb) {
                        dev_err(chip->card->dev,
                                "dsp_spos: failed to create SRCtaskSCB\n");
                        return NULL;
                }

                /* cs46xx_dsp_set_src_sample_rate(chip,src_scb,sample_rate); */

                ins->nsrc_scb ++;
        } 
  
  
        snprintf (scb_name,DSP_MAX_SCB_NAME,"PCMReader_SCB%d",pcm_index);

        dev_dbg(chip->card->dev, "dsp_spos: creating PCM \"%s\" (%d)\n",
                scb_name, pcm_channel_id);

        pcm_scb = cs46xx_dsp_create_pcm_reader_scb(chip,scb_name,
                                                   pcm_reader_buffer_addr[pcm_index],
                                                   /* 0x200 - 400 PCMreader SCBs */
                                                   (pcm_index * 0x10) + 0x200,
                                                   pcm_index,    /* virtual channel 0-31 */
                                                   hw_dma_addr,  /* pcm hw addr */
                           NULL,         /* parent SCB ptr */
                           0             /* insert point */ 
                           );

        if (!pcm_scb) {
                dev_err(chip->card->dev,
                        "dsp_spos: failed to create PCMreaderSCB\n");
                return NULL;
        }
        
        spin_lock_irqsave(&chip->reg_lock, flags);
        ins->pcm_channels[pcm_index].sample_rate = sample_rate;
        ins->pcm_channels[pcm_index].pcm_reader_scb = pcm_scb;
        ins->pcm_channels[pcm_index].src_scb = src_scb;
        ins->pcm_channels[pcm_index].unlinked = 1;
        ins->pcm_channels[pcm_index].private_data = private_data;
        ins->pcm_channels[pcm_index].src_slot = src_index;
        ins->pcm_channels[pcm_index].active = 1;
        ins->pcm_channels[pcm_index].pcm_slot = pcm_index;
        ins->pcm_channels[pcm_index].mixer_scb = mixer_scb;
        ins->npcm_channels ++;
        spin_unlock_irqrestore(&chip->reg_lock, flags);

        return (ins->pcm_channels + pcm_index);
}

int cs46xx_dsp_pcm_channel_set_period (struct snd_cs46xx * chip,
                                       struct dsp_pcm_channel_descriptor * pcm_channel,
                                       int period_size)
{
        u32 temp = snd_cs46xx_peek (chip,pcm_channel->pcm_reader_scb->address << 2);
        temp &= ~DMA_RQ_C1_SOURCE_SIZE_MASK;

        switch (period_size) {
        case 2048:
                temp |= DMA_RQ_C1_SOURCE_MOD1024;
                break;
        case 1024:
                temp |= DMA_RQ_C1_SOURCE_MOD512;
                break;
        case 512:
                temp |= DMA_RQ_C1_SOURCE_MOD256;
                break;
        case 256:
                temp |= DMA_RQ_C1_SOURCE_MOD128;
                break;
        case 128:
                temp |= DMA_RQ_C1_SOURCE_MOD64;
                break;
        case 64:
                temp |= DMA_RQ_C1_SOURCE_MOD32;
                break;                
        case 32:
                temp |= DMA_RQ_C1_SOURCE_MOD16;
                break; 
        default:
                dev_dbg(chip->card->dev,
                        "period size (%d) not supported by HW\n", period_size);
                return -EINVAL;
        }

        snd_cs46xx_poke (chip,pcm_channel->pcm_reader_scb->address << 2,temp);

        return 0;
}

int cs46xx_dsp_pcm_ostream_set_period (struct snd_cs46xx * chip,
                                       int period_size)
{
        u32 temp = snd_cs46xx_peek (chip,WRITEBACK_SCB_ADDR << 2);
        temp &= ~DMA_RQ_C1_DEST_SIZE_MASK;

        switch (period_size) {
        case 2048:
                temp |= DMA_RQ_C1_DEST_MOD1024;
                break;
        case 1024:
                temp |= DMA_RQ_C1_DEST_MOD512;
                break;
        case 512:
                temp |= DMA_RQ_C1_DEST_MOD256;
                break;
        case 256:
                temp |= DMA_RQ_C1_DEST_MOD128;
                break;
        case 128:
                temp |= DMA_RQ_C1_DEST_MOD64;
                break;
        case 64:
                temp |= DMA_RQ_C1_DEST_MOD32;
                break;                
        case 32:
                temp |= DMA_RQ_C1_DEST_MOD16;
                break; 
        default:
                dev_dbg(chip->card->dev,
                        "period size (%d) not supported by HW\n", period_size);
                return -EINVAL;
        }

        snd_cs46xx_poke (chip,WRITEBACK_SCB_ADDR << 2,temp);

        return 0;
}

void cs46xx_dsp_destroy_pcm_channel (struct snd_cs46xx * chip,
                                     struct dsp_pcm_channel_descriptor * pcm_channel)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;
        unsigned long flags;

        if (snd_BUG_ON(!pcm_channel->active ||
                       ins->npcm_channels <= 0 ||
                       pcm_channel->src_scb->ref_count <= 0))
                return;

        spin_lock_irqsave(&chip->reg_lock, flags);
        pcm_channel->unlinked = 1;
        pcm_channel->active = 0;
        pcm_channel->private_data = NULL;
        pcm_channel->src_scb->ref_count --;
        ins->npcm_channels --;
        spin_unlock_irqrestore(&chip->reg_lock, flags);

        cs46xx_dsp_remove_scb(chip,pcm_channel->pcm_reader_scb);

        if (!pcm_channel->src_scb->ref_count) {
                cs46xx_dsp_remove_scb(chip,pcm_channel->src_scb);

                if (snd_BUG_ON(pcm_channel->src_slot < 0 ||
                               pcm_channel->src_slot >= DSP_MAX_SRC_NR))
                        return;

                ins->src_scb_slots[pcm_channel->src_slot] = 0;
                ins->nsrc_scb --;
        }
}

int cs46xx_dsp_pcm_unlink (struct snd_cs46xx * chip,
                           struct dsp_pcm_channel_descriptor * pcm_channel)
{
        unsigned long flags;

        if (snd_BUG_ON(!pcm_channel->active ||
                       chip->dsp_spos_instance->npcm_channels <= 0))
                return -EIO;

        spin_lock_irqsave(&chip->reg_lock, flags);
        if (pcm_channel->unlinked) {
                spin_unlock_irqrestore(&chip->reg_lock, flags);
                return -EIO;
        }

        pcm_channel->unlinked = 1;

        _dsp_unlink_scb (chip,pcm_channel->pcm_reader_scb);
        spin_unlock_irqrestore(&chip->reg_lock, flags);

        return 0;
}

int cs46xx_dsp_pcm_link (struct snd_cs46xx * chip,
                         struct dsp_pcm_channel_descriptor * pcm_channel)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;
        struct dsp_scb_descriptor * parent_scb;
        struct dsp_scb_descriptor * src_scb = pcm_channel->src_scb;
        unsigned long flags;

        spin_lock_irqsave(&chip->reg_lock, flags);

        if (pcm_channel->unlinked == 0) {
                spin_unlock_irqrestore(&chip->reg_lock, flags);
                return -EIO;
        }

        parent_scb = src_scb;

        if (src_scb->sub_list_ptr != ins->the_null_scb) {
                src_scb->sub_list_ptr->parent_scb_ptr = pcm_channel->pcm_reader_scb;
                pcm_channel->pcm_reader_scb->next_scb_ptr = src_scb->sub_list_ptr;
        }

        src_scb->sub_list_ptr = pcm_channel->pcm_reader_scb;

        snd_BUG_ON(pcm_channel->pcm_reader_scb->parent_scb_ptr);
        pcm_channel->pcm_reader_scb->parent_scb_ptr = parent_scb;

        /* update SCB entry in DSP RAM */
        cs46xx_dsp_spos_update_scb(chip,pcm_channel->pcm_reader_scb);

        /* update parent SCB entry */
        cs46xx_dsp_spos_update_scb(chip,parent_scb);

        pcm_channel->unlinked = 0;
        spin_unlock_irqrestore(&chip->reg_lock, flags);
        return 0;
}

struct dsp_scb_descriptor *
cs46xx_add_record_source (struct snd_cs46xx *chip, struct dsp_scb_descriptor * source,
                          u16 addr, char * scb_name)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;
        struct dsp_scb_descriptor * parent;
        struct dsp_scb_descriptor * pcm_input;
        int insert_point;

        if (snd_BUG_ON(!ins->record_mixer_scb))
                return NULL;

        if (ins->record_mixer_scb->sub_list_ptr != ins->the_null_scb) {
                parent = find_next_free_scb (chip,ins->record_mixer_scb->sub_list_ptr);
                insert_point = SCB_ON_PARENT_NEXT_SCB;
        } else {
                parent = ins->record_mixer_scb;
                insert_point = SCB_ON_PARENT_SUBLIST_SCB;
        }

        pcm_input = cs46xx_dsp_create_pcm_serial_input_scb(chip,scb_name,addr,
                                                           source, parent,
                                                           insert_point);

        return pcm_input;
}

int cs46xx_src_unlink(struct snd_cs46xx *chip, struct dsp_scb_descriptor * src)
{
        unsigned long flags;

        if (snd_BUG_ON(!src->parent_scb_ptr))
                return -EINVAL;

        /* mute SCB */
        cs46xx_dsp_scb_set_volume (chip,src,0,0);

        spin_lock_irqsave(&chip->reg_lock, flags);
        _dsp_unlink_scb (chip,src);
        spin_unlock_irqrestore(&chip->reg_lock, flags);

        return 0;
}

int cs46xx_src_link(struct snd_cs46xx *chip, struct dsp_scb_descriptor * src)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;
        struct dsp_scb_descriptor * parent_scb;

        if (snd_BUG_ON(src->parent_scb_ptr))
                return -EINVAL;
        if (snd_BUG_ON(!ins->master_mix_scb))
                return -EINVAL;

        if (ins->master_mix_scb->sub_list_ptr != ins->the_null_scb) {
                parent_scb = find_next_free_scb (chip,ins->master_mix_scb->sub_list_ptr);
                parent_scb->next_scb_ptr = src;
        } else {
                parent_scb = ins->master_mix_scb;
                parent_scb->sub_list_ptr = src;
        }

        src->parent_scb_ptr = parent_scb;

        /* update entry in DSP RAM */
        cs46xx_dsp_spos_update_scb(chip,parent_scb);
  
        return 0;
}

int cs46xx_dsp_enable_spdif_out (struct snd_cs46xx *chip)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;

        if ( ! (ins->spdif_status_out & DSP_SPDIF_STATUS_HW_ENABLED) ) {
                cs46xx_dsp_enable_spdif_hw (chip);
        }

        /* dont touch anything if SPDIF is open */
        if ( ins->spdif_status_out & DSP_SPDIF_STATUS_PLAYBACK_OPEN) {
                /* when cs46xx_iec958_post_close(...) is called it
                   will call this function if necessary depending on
                   this bit */
                ins->spdif_status_out |= DSP_SPDIF_STATUS_OUTPUT_ENABLED;

                return -EBUSY;
        }

        if (snd_BUG_ON(ins->asynch_tx_scb))
                return -EINVAL;
        if (snd_BUG_ON(ins->master_mix_scb->next_scb_ptr !=
                       ins->the_null_scb))
                return -EINVAL;

        /* reset output snooper sample buffer pointer */
        snd_cs46xx_poke (chip, (ins->ref_snoop_scb->address + 2) << 2,
                         (OUTPUT_SNOOP_BUFFER + 0x10) << 0x10 );
        
        /* The asynch. transfer task */
        ins->asynch_tx_scb = cs46xx_dsp_create_asynch_fg_tx_scb(chip,"AsynchFGTxSCB",ASYNCTX_SCB_ADDR,
                                                                SPDIFO_SCB_INST,
                                                                SPDIFO_IP_OUTPUT_BUFFER1,
                                                                ins->master_mix_scb,
                                                                SCB_ON_PARENT_NEXT_SCB);
        if (!ins->asynch_tx_scb) return -ENOMEM;

        ins->spdif_pcm_input_scb = cs46xx_dsp_create_pcm_serial_input_scb(chip,"PCMSerialInput_II",
                                                                          PCMSERIALINII_SCB_ADDR,
                                                                          ins->ref_snoop_scb,
                                                                          ins->asynch_tx_scb,
                                                                          SCB_ON_PARENT_SUBLIST_SCB);
  
        
        if (!ins->spdif_pcm_input_scb) return -ENOMEM;

        /* monitor state */
        ins->spdif_status_out |= DSP_SPDIF_STATUS_OUTPUT_ENABLED;

        return 0;
}

int  cs46xx_dsp_disable_spdif_out (struct snd_cs46xx *chip)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;

        /* dont touch anything if SPDIF is open */
        if ( ins->spdif_status_out & DSP_SPDIF_STATUS_PLAYBACK_OPEN) {
                ins->spdif_status_out &= ~DSP_SPDIF_STATUS_OUTPUT_ENABLED;
                return -EBUSY;
        }

        /* check integrety */
        if (snd_BUG_ON(!ins->asynch_tx_scb))
                return -EINVAL;
        if (snd_BUG_ON(!ins->spdif_pcm_input_scb))
                return -EINVAL;
        if (snd_BUG_ON(ins->master_mix_scb->next_scb_ptr != ins->asynch_tx_scb))
                return -EINVAL;
        if (snd_BUG_ON(ins->asynch_tx_scb->parent_scb_ptr !=
                       ins->master_mix_scb))
                return -EINVAL;

        cs46xx_dsp_remove_scb (chip,ins->spdif_pcm_input_scb);
        cs46xx_dsp_remove_scb (chip,ins->asynch_tx_scb);

        ins->spdif_pcm_input_scb = NULL;
        ins->asynch_tx_scb = NULL;

        /* clear buffer to prevent any undesired noise */
        _dsp_clear_sample_buffer(chip,SPDIFO_IP_OUTPUT_BUFFER1,256);

        /* monitor state */
        ins->spdif_status_out  &= ~DSP_SPDIF_STATUS_OUTPUT_ENABLED;


        return 0;
}

int cs46xx_iec958_pre_open (struct snd_cs46xx *chip)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;

        if ( ins->spdif_status_out & DSP_SPDIF_STATUS_OUTPUT_ENABLED ) {
                /* remove AsynchFGTxSCB and and PCMSerialInput_II */
                cs46xx_dsp_disable_spdif_out (chip);

                /* save state */
                ins->spdif_status_out |= DSP_SPDIF_STATUS_OUTPUT_ENABLED;
        }
        
        /* if not enabled already */
        if ( !(ins->spdif_status_out & DSP_SPDIF_STATUS_HW_ENABLED) ) {
                cs46xx_dsp_enable_spdif_hw (chip);
        }

        /* Create the asynch. transfer task  for playback */
        ins->asynch_tx_scb = cs46xx_dsp_create_asynch_fg_tx_scb(chip,"AsynchFGTxSCB",ASYNCTX_SCB_ADDR,
                                                                SPDIFO_SCB_INST,
                                                                SPDIFO_IP_OUTPUT_BUFFER1,
                                                                ins->master_mix_scb,
                                                                SCB_ON_PARENT_NEXT_SCB);


        /* set spdif channel status value for streaming */
        cs46xx_poke_via_dsp (chip,SP_SPDOUT_CSUV, ins->spdif_csuv_stream);

        ins->spdif_status_out  |= DSP_SPDIF_STATUS_PLAYBACK_OPEN;

        return 0;
}

int cs46xx_iec958_post_close (struct snd_cs46xx *chip)
{
        struct dsp_spos_instance * ins = chip->dsp_spos_instance;

        if (snd_BUG_ON(!ins->asynch_tx_scb))
                return -EINVAL;

        ins->spdif_status_out  &= ~DSP_SPDIF_STATUS_PLAYBACK_OPEN;

        /* restore settings */
        cs46xx_poke_via_dsp (chip,SP_SPDOUT_CSUV, ins->spdif_csuv_default);
        
        /* deallocate stuff */
        if (ins->spdif_pcm_input_scb != NULL) {
                cs46xx_dsp_remove_scb (chip,ins->spdif_pcm_input_scb);
                ins->spdif_pcm_input_scb = NULL;
        }

        cs46xx_dsp_remove_scb (chip,ins->asynch_tx_scb);
        ins->asynch_tx_scb = NULL;

        /* clear buffer to prevent any undesired noise */
        _dsp_clear_sample_buffer(chip,SPDIFO_IP_OUTPUT_BUFFER1,256);

        /* restore state */
        if ( ins->spdif_status_out & DSP_SPDIF_STATUS_OUTPUT_ENABLED ) {
                cs46xx_dsp_enable_spdif_out (chip);
        }
        
        return 0;
}