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via82cxxx_audio.c

/*
 * Support for VIA 82Cxxx Audio Codecs
 * Copyright 1999,2000 Jeff Garzik
 *
 * Updated to support the VIA 8233/8235 audio subsystem
 * Alan Cox <alan@redhat.com> (C) Copyright 2002, 2003 Red Hat Inc
 *
 * Distributed under the GNU GENERAL PUBLIC LICENSE (GPL) Version 2.
 * See the "COPYING" file distributed with this software for more info.
 * NO WARRANTY
 *
 * For a list of known bugs (errata) and documentation,
 * see via-audio.pdf in Documentation/DocBook.
 * If this documentation does not exist, run "make pdfdocs".
 */


#define VIA_VERSION     "1.9.1-ac4-2.5"


#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/pci.h>
#include <linux/poison.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/proc_fs.h>
#include <linux/spinlock.h>
#include <linux/sound.h>
#include <linux/poll.h>
#include <linux/soundcard.h>
#include <linux/ac97_codec.h>
#include <linux/smp_lock.h>
#include <linux/ioport.h>
#include <linux/delay.h>
#include <linux/dma-mapping.h>
#include <asm/io.h>
#include <asm/uaccess.h>
#include <linux/mutex.h>

#include "sound_config.h"
#include "dev_table.h"
#include "mpu401.h"


#undef VIA_DEBUG  /* define to enable debugging output and checks */
#ifdef VIA_DEBUG
/* note: prints function name for you */
#define DPRINTK(fmt, args...) printk(KERN_DEBUG "%s: " fmt, __FUNCTION__ , ## args)
#else
#define DPRINTK(fmt, args...)
#endif

#undef VIA_NDEBUG /* define to disable lightweight runtime checks */
#ifdef VIA_NDEBUG
#define assert(expr)
#else
#define assert(expr) \
        if(!(expr)) {                           \
        printk( "Assertion failed! %s,%s,%s,line=%d\n",     \
        #expr,__FILE__,__FUNCTION__,__LINE__);        \
        }
#endif

#define VIA_SUPPORT_MMAP 1 /* buggy, for now... */

#define MAX_CARDS 1

#define VIA_CARD_NAME   "VIA 82Cxxx Audio driver " VIA_VERSION
#define VIA_MODULE_NAME "via82cxxx"
#define PFX       VIA_MODULE_NAME ": "

#define VIA_COUNTER_LIMIT     100000

/* size of DMA buffers */
#define VIA_MAX_BUFFER_DMA_PAGES    32

/* buffering default values in ms */
#define VIA_DEFAULT_FRAG_TIME       20
#define VIA_DEFAULT_BUFFER_TIME           500

/* the hardware has a 256 fragment limit */
#define VIA_MIN_FRAG_NUMBER         2
#define VIA_MAX_FRAG_NUMBER         128

#define VIA_MAX_FRAG_SIZE           PAGE_SIZE
#define VIA_MIN_FRAG_SIZE           (VIA_MAX_BUFFER_DMA_PAGES * PAGE_SIZE / VIA_MAX_FRAG_NUMBER)


/* 82C686 function 5 (audio codec) PCI configuration registers */
#define VIA_ACLINK_STATUS     0x40
#define VIA_ACLINK_CTRL       0x41
#define VIA_FUNC_ENABLE       0x42
#define VIA_PNP_CONTROL       0x43
#define VIA_FM_NMI_CTRL       0x48

/*
 * controller base 0 (scatter-gather) registers
 *
 * NOTE: Via datasheet lists first channel as "read"
 * channel and second channel as "write" channel.
 * I changed the naming of the constants to be more
 * clear than I felt the datasheet to be.
 */

#define VIA_BASE0_PCM_OUT_CHAN      0x00 /* output PCM to user */
#define VIA_BASE0_PCM_OUT_CHAN_STATUS 0x00
#define VIA_BASE0_PCM_OUT_CHAN_CTRL 0x01
#define VIA_BASE0_PCM_OUT_CHAN_TYPE 0x02

#define VIA_BASE0_PCM_IN_CHAN       0x10 /* input PCM from user */
#define VIA_BASE0_PCM_IN_CHAN_STATUS      0x10
#define VIA_BASE0_PCM_IN_CHAN_CTRL  0x11
#define VIA_BASE0_PCM_IN_CHAN_TYPE  0x12

/* offsets from base */
#define VIA_PCM_STATUS              0x00
#define VIA_PCM_CONTROL             0x01
#define VIA_PCM_TYPE                0x02
#define VIA_PCM_LEFTVOL             0x02
#define VIA_PCM_RIGHTVOL            0x03
#define VIA_PCM_TABLE_ADDR          0x04
#define VIA_PCM_STOPRATE            0x08  /* 8233+ */
#define VIA_PCM_BLOCK_COUNT         0x0C

/* XXX unused DMA channel for FM PCM data */
#define VIA_BASE0_FM_OUT_CHAN       0x20
#define VIA_BASE0_FM_OUT_CHAN_STATUS      0x20
#define VIA_BASE0_FM_OUT_CHAN_CTRL  0x21
#define VIA_BASE0_FM_OUT_CHAN_TYPE  0x22

/* Six channel audio output on 8233 */
#define VIA_BASE0_MULTI_OUT_CHAN          0x40
#define VIA_BASE0_MULTI_OUT_CHAN_STATUS         0x40
#define VIA_BASE0_MULTI_OUT_CHAN_CTRL           0x41
#define VIA_BASE0_MULTI_OUT_CHAN_TYPE           0x42

#define VIA_BASE0_AC97_CTRL         0x80
#define VIA_BASE0_SGD_STATUS_SHADOW 0x84
#define VIA_BASE0_GPI_INT_ENABLE    0x8C
#define VIA_INTR_OUT                ((1<<0) |  (1<<4) |  (1<<8))
#define VIA_INTR_IN                 ((1<<1) |  (1<<5) |  (1<<9))
#define VIA_INTR_FM                 ((1<<2) |  (1<<6) | (1<<10))
#define VIA_INTR_MASK         (VIA_INTR_OUT | VIA_INTR_IN | VIA_INTR_FM)

/* Newer VIA we need to monitor the low 3 bits of each channel. This
   mask covers the channels we don't yet use as well 
 */
 
#define VIA_NEW_INTR_MASK           0x77077777UL

/* VIA_BASE0_AUDIO_xxx_CHAN_TYPE bits */
#define VIA_IRQ_ON_FLAG             (1<<0)      /* int on each flagged scatter block */
#define VIA_IRQ_ON_EOL              (1<<1)      /* int at end of scatter list */
#define VIA_INT_SEL_PCI_LAST_LINE_READ    (0)   /* int at PCI read of last line */
#define VIA_INT_SEL_LAST_SAMPLE_SENT      (1<<2)      /* int at last sample sent */
#define VIA_INT_SEL_ONE_LINE_LEFT   (1<<3)      /* int at less than one line to send */
#define VIA_PCM_FMT_STEREO          (1<<4)      /* PCM stereo format (bit clear == mono) */
#define VIA_PCM_FMT_16BIT           (1<<5)      /* PCM 16-bit format (bit clear == 8-bit) */
#define VIA_PCM_REC_FIFO            (1<<6)      /* PCM Recording FIFO */
#define VIA_RESTART_SGD_ON_EOL            (1<<7)      /* restart scatter-gather at EOL */
#define VIA_PCM_FMT_MASK            (VIA_PCM_FMT_STEREO|VIA_PCM_FMT_16BIT)
#define VIA_CHAN_TYPE_MASK          (VIA_RESTART_SGD_ON_EOL | \
                               VIA_IRQ_ON_FLAG | \
                               VIA_IRQ_ON_EOL)
#define VIA_CHAN_TYPE_INT_SELECT    (VIA_INT_SEL_LAST_SAMPLE_SENT)

/* PCI configuration register bits and masks */
#define VIA_CR40_AC97_READY   0x01
#define VIA_CR40_AC97_LOW_POWER     0x02
#define VIA_CR40_SECONDARY_READY 0x04

#define VIA_CR41_AC97_ENABLE  0x80 /* enable AC97 codec */
#define VIA_CR41_AC97_RESET   0x40 /* clear bit to reset AC97 */
#define VIA_CR41_AC97_WAKEUP  0x20 /* wake up from power-down mode */
#define VIA_CR41_AC97_SDO     0x10 /* force Serial Data Out (SDO) high */
#define VIA_CR41_VRA          0x08 /* enable variable sample rate */
#define VIA_CR41_PCM_ENABLE   0x04 /* AC Link SGD Read Channel PCM Data Output */
#define VIA_CR41_FM_PCM_ENABLE      0x02 /* AC Link FM Channel PCM Data Out */
#define VIA_CR41_SB_PCM_ENABLE      0x01 /* AC Link SB PCM Data Output */
#define VIA_CR41_BOOT_MASK    (VIA_CR41_AC97_ENABLE | \
                         VIA_CR41_AC97_WAKEUP | \
                         VIA_CR41_AC97_SDO)
#define VIA_CR41_RUN_MASK     (VIA_CR41_AC97_ENABLE | \
                         VIA_CR41_AC97_RESET | \
                         VIA_CR41_VRA | \
                         VIA_CR41_PCM_ENABLE)

#define VIA_CR42_SB_ENABLE    0x01
#define VIA_CR42_MIDI_ENABLE  0x02
#define VIA_CR42_FM_ENABLE    0x04
#define VIA_CR42_GAME_ENABLE  0x08
#define VIA_CR42_MIDI_IRQMASK   0x40
#define VIA_CR42_MIDI_PNP     0x80

#define VIA_CR44_SECOND_CODEC_SUPPORT     (1 << 6)
#define VIA_CR44_AC_LINK_ACCESS           (1 << 7)

#define VIA_CR48_FM_TRAP_TO_NMI           (1 << 2)

/* controller base 0 register bitmasks */
#define VIA_INT_DISABLE_MASK        (~(0x01|0x02))
#define VIA_SGD_STOPPED             (1 << 2)
#define VIA_SGD_PAUSED              (1 << 6)
#define VIA_SGD_ACTIVE              (1 << 7)
#define VIA_SGD_TERMINATE           (1 << 6)
#define VIA_SGD_FLAG                (1 << 0)
#define VIA_SGD_EOL                 (1 << 1)
#define VIA_SGD_START               (1 << 7)

#define VIA_CR80_FIRST_CODEC        0
#define VIA_CR80_SECOND_CODEC       (1 << 30)
#define VIA_CR80_FIRST_CODEC_VALID  (1 << 25)
#define VIA_CR80_VALID              (1 << 25)
#define VIA_CR80_SECOND_CODEC_VALID (1 << 27)
#define VIA_CR80_BUSY               (1 << 24)
#define VIA_CR83_BUSY               (1)
#define VIA_CR83_FIRST_CODEC_VALID  (1 << 1)
#define VIA_CR80_READ               (1 << 23)
#define VIA_CR80_WRITE_MODE         0
#define VIA_CR80_REG_IDX(idx)       ((((idx) & 0xFF) >> 1) << 16)

/* capabilities we announce */
#ifdef VIA_SUPPORT_MMAP
#define VIA_DSP_CAP (DSP_CAP_REVISION | DSP_CAP_DUPLEX | DSP_CAP_MMAP | \
                 DSP_CAP_TRIGGER | DSP_CAP_REALTIME)
#else
#define VIA_DSP_CAP (DSP_CAP_REVISION | DSP_CAP_DUPLEX | \
                 DSP_CAP_TRIGGER | DSP_CAP_REALTIME)
#endif

/* scatter-gather DMA table entry, exactly as passed to hardware */
struct via_sgd_table {
      u32 addr;
      u32 count;  /* includes additional VIA_xxx bits also */
};

#define VIA_EOL (1 << 31)
#define VIA_FLAG (1 << 30)
#define VIA_STOP (1 << 29)


enum via_channel_states {
      sgd_stopped = 0,
      sgd_in_progress = 1,
};


struct via_buffer_pgtbl {
      dma_addr_t handle;
      void *cpuaddr;
};


struct via_channel {
      atomic_t n_frags;
      atomic_t hw_ptr;
      wait_queue_head_t wait;

      unsigned int sw_ptr;
      unsigned int slop_len;
      unsigned int n_irqs;
      int bytes;

      unsigned is_active : 1;
      unsigned is_record : 1;
      unsigned is_mapped : 1;
      unsigned is_enabled : 1;
      unsigned is_multi: 1;   /* 8233 6 channel */
      u8 pcm_fmt;       /* VIA_PCM_FMT_xxx */
      u8 channels;            /* Channel count */

      unsigned rate;          /* sample rate */
      unsigned int frag_size;
      unsigned int frag_number;
      
      unsigned char intmask;

      volatile struct via_sgd_table *sgtable;
      dma_addr_t sgt_handle;

      unsigned int page_number;
      struct via_buffer_pgtbl pgtbl[VIA_MAX_BUFFER_DMA_PAGES];

      long iobase;

      const char *name;
};


/* data stored for each chip */
struct via_info {
      struct pci_dev *pdev;
      long baseaddr;

      struct ac97_codec *ac97;
      spinlock_t ac97_lock;
      spinlock_t lock;
      int card_num;           /* unique card number, from 0 */

      int dev_dsp;            /* /dev/dsp index from register_sound_dsp() */

      unsigned rev_h : 1;
      unsigned legacy: 1;     /* Has legacy ports */
      unsigned intmask: 1;    /* Needs int bits */
      unsigned sixchannel: 1; /* 8233/35 with 6 channel support */
      unsigned volume: 1;

      unsigned locked_rate : 1;
      
      int mixer_vol;          /* 8233/35 volume  - not yet implemented */

      struct mutex syscall_mutex;
      struct mutex open_mutex;

      /* The 8233/8235 have 4 DX audio channels, two record and
         one six channel out. We bind ch_in to DX 1, ch_out to multichannel
         and ch_fm to DX 2. DX 3 and REC0/REC1 are unused at the
         moment */
         
      struct via_channel ch_in;
      struct via_channel ch_out;
      struct via_channel ch_fm;

#ifdef CONFIG_MIDI_VIA82CXXX
        void *midi_devc;
        struct address_info midi_info;
#endif
};


/* number of cards, used for assigning unique numbers to cards */
static unsigned via_num_cards;



/****************************************************************
 *
 * prototypes
 *
 *
 */

static int via_init_one (struct pci_dev *dev, const struct pci_device_id *id);
static void __devexit via_remove_one (struct pci_dev *pdev);

static ssize_t via_dsp_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos);
static ssize_t via_dsp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos);
static unsigned int via_dsp_poll(struct file *file, struct poll_table_struct *wait);
static int via_dsp_ioctl (struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg);
static int via_dsp_open (struct inode *inode, struct file *file);
static int via_dsp_release(struct inode *inode, struct file *file);
static int via_dsp_mmap(struct file *file, struct vm_area_struct *vma);

static u16 via_ac97_read_reg (struct ac97_codec *codec, u8 reg);
static void via_ac97_write_reg (struct ac97_codec *codec, u8 reg, u16 value);
static u8 via_ac97_wait_idle (struct via_info *card);

static void via_chan_free (struct via_info *card, struct via_channel *chan);
static void via_chan_clear (struct via_info *card, struct via_channel *chan);
static void via_chan_pcm_fmt (struct via_channel *chan, int reset);
static void via_chan_buffer_free (struct via_info *card, struct via_channel *chan);


/****************************************************************
 *
 * Various data the driver needs
 *
 *
 */


static struct pci_device_id via_pci_tbl[] = {
      { PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_82C686_5,
        PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
      { PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8233_5,
        PCI_ANY_ID, PCI_ANY_ID, 0, 0, 1},
      { 0, }
};
MODULE_DEVICE_TABLE(pci,via_pci_tbl);


static struct pci_driver via_driver = {
      .name       = VIA_MODULE_NAME,
      .id_table   = via_pci_tbl,
      .probe            = via_init_one,
      .remove           = __devexit_p(via_remove_one),
};


/****************************************************************
 *
 * Low-level base 0 register read/write helpers
 *
 *
 */

/**
 *    via_chan_stop - Terminate DMA on specified PCM channel
 *    @iobase: PCI base address for SGD channel registers
 *
 *    Terminate scatter-gather DMA operation for given
 *    channel (derived from @iobase), if DMA is active.
 *
 *    Note that @iobase is not the PCI base address,
 *    but the PCI base address plus an offset to
 *    one of three PCM channels supported by the chip.
 *
 */

static inline void via_chan_stop (long iobase)
{
      if (inb (iobase + VIA_PCM_STATUS) & VIA_SGD_ACTIVE)
            outb (VIA_SGD_TERMINATE, iobase + VIA_PCM_CONTROL);
}


/**
 *    via_chan_status_clear - Clear status flags on specified DMA channel
 *    @iobase: PCI base address for SGD channel registers
 *
 *    Clear any pending status flags for the given
 *    DMA channel (derived from @iobase), if any
 *    flags are asserted.
 *
 *    Note that @iobase is not the PCI base address,
 *    but the PCI base address plus an offset to
 *    one of three PCM channels supported by the chip.
 *
 */

static inline void via_chan_status_clear (long iobase)
{
      u8 tmp = inb (iobase + VIA_PCM_STATUS);

      if (tmp != 0)
            outb (tmp, iobase + VIA_PCM_STATUS);
}


/**
 *    sg_begin - Begin recording or playback on a PCM channel
 *    @chan: Channel for which DMA operation shall begin
 *
 *    Start scatter-gather DMA for the given channel.
 *
 */

static inline void sg_begin (struct via_channel *chan)
{
      DPRINTK("Start with intmask %d\n", chan->intmask);
      DPRINTK("About to start from %d to %d\n", 
            inl(chan->iobase + VIA_PCM_BLOCK_COUNT),
            inb(chan->iobase + VIA_PCM_STOPRATE + 3));
      outb (VIA_SGD_START|chan->intmask, chan->iobase + VIA_PCM_CONTROL);
      DPRINTK("Status is now %02X\n", inb(chan->iobase + VIA_PCM_STATUS));
      DPRINTK("Control is now %02X\n", inb(chan->iobase + VIA_PCM_CONTROL));
}


static int sg_active (long iobase)
{
      u8 tmp = inb (iobase + VIA_PCM_STATUS);
      if ((tmp & VIA_SGD_STOPPED) || (tmp & VIA_SGD_PAUSED)) {
            printk(KERN_WARNING "via82cxxx warning: SG stopped or paused\n");
            return 0;
      }
      if (tmp & VIA_SGD_ACTIVE)
            return 1;
      return 0;
}

static int via_sg_offset(struct via_channel *chan)
{
      return inl (chan->iobase + VIA_PCM_BLOCK_COUNT) & 0x00FFFFFF;
}

/****************************************************************
 *
 * Miscellaneous debris
 *
 *
 */


/**
 *    via_syscall_down - down the card-specific syscell semaphore
 *    @card: Private info for specified board
 *    @nonblock: boolean, non-zero if O_NONBLOCK is set
 *
 *    Encapsulates standard method of acquiring the syscall sem.
 *
 *    Returns negative errno on error, or zero for success.
 */

static inline int via_syscall_down (struct via_info *card, int nonblock)
{
      /* Thomas Sailer:
       * EAGAIN is supposed to be used if IO is pending,
       * not if there is contention on some internal
       * synchronization primitive which should be
       * held only for a short time anyway
       */
      nonblock = 0;

      if (nonblock) {
            if (!mutex_trylock(&card->syscall_mutex))
                  return -EAGAIN;
      } else {
            if (mutex_lock_interruptible(&card->syscall_mutex))
                  return -ERESTARTSYS;
      }

      return 0;
}


/**
 *    via_stop_everything - Stop all audio operations
 *    @card: Private info for specified board
 *
 *    Stops all DMA operations and interrupts, and clear
 *    any pending status bits resulting from those operations.
 */

static void via_stop_everything (struct via_info *card)
{
      u8 tmp, new_tmp;

      DPRINTK ("ENTER\n");

      assert (card != NULL);

      /*
       * terminate any existing operations on audio read/write channels
       */
      via_chan_stop (card->baseaddr + VIA_BASE0_PCM_OUT_CHAN);
      via_chan_stop (card->baseaddr + VIA_BASE0_PCM_IN_CHAN);
      via_chan_stop (card->baseaddr + VIA_BASE0_FM_OUT_CHAN);
      if(card->sixchannel)
            via_chan_stop (card->baseaddr + VIA_BASE0_MULTI_OUT_CHAN);

      /*
       * clear any existing stops / flags (sanity check mainly)
       */
      via_chan_status_clear (card->baseaddr + VIA_BASE0_PCM_OUT_CHAN);
      via_chan_status_clear (card->baseaddr + VIA_BASE0_PCM_IN_CHAN);
      via_chan_status_clear (card->baseaddr + VIA_BASE0_FM_OUT_CHAN);
      if(card->sixchannel)
            via_chan_status_clear (card->baseaddr + VIA_BASE0_MULTI_OUT_CHAN);

      /*
       * clear any enabled interrupt bits
       */
      tmp = inb (card->baseaddr + VIA_BASE0_PCM_OUT_CHAN_TYPE);
      new_tmp = tmp & ~(VIA_IRQ_ON_FLAG|VIA_IRQ_ON_EOL|VIA_RESTART_SGD_ON_EOL);
      if (tmp != new_tmp)
            outb (0, card->baseaddr + VIA_BASE0_PCM_OUT_CHAN_TYPE);

      tmp = inb (card->baseaddr + VIA_BASE0_PCM_IN_CHAN_TYPE);
      new_tmp = tmp & ~(VIA_IRQ_ON_FLAG|VIA_IRQ_ON_EOL|VIA_RESTART_SGD_ON_EOL);
      if (tmp != new_tmp)
            outb (0, card->baseaddr + VIA_BASE0_PCM_IN_CHAN_TYPE);

      tmp = inb (card->baseaddr + VIA_BASE0_FM_OUT_CHAN_TYPE);
      new_tmp = tmp & ~(VIA_IRQ_ON_FLAG|VIA_IRQ_ON_EOL|VIA_RESTART_SGD_ON_EOL);
      if (tmp != new_tmp)
            outb (0, card->baseaddr + VIA_BASE0_FM_OUT_CHAN_TYPE);

      if(card->sixchannel)
      {
            tmp = inb (card->baseaddr + VIA_BASE0_MULTI_OUT_CHAN_TYPE);
            new_tmp = tmp & ~(VIA_IRQ_ON_FLAG|VIA_IRQ_ON_EOL|VIA_RESTART_SGD_ON_EOL);
            if (tmp != new_tmp)
                  outb (0, card->baseaddr + VIA_BASE0_MULTI_OUT_CHAN_TYPE);
      }

      udelay(10);

      /*
       * clear any existing flags
       */
      via_chan_status_clear (card->baseaddr + VIA_BASE0_PCM_OUT_CHAN);
      via_chan_status_clear (card->baseaddr + VIA_BASE0_PCM_IN_CHAN);
      via_chan_status_clear (card->baseaddr + VIA_BASE0_FM_OUT_CHAN);

      DPRINTK ("EXIT\n");
}


/**
 *    via_set_rate - Set PCM rate for given channel
 *    @ac97: Pointer to generic codec info struct
 *    @chan: Private info for specified channel
 *    @rate: Desired PCM sample rate, in Khz
 *
 *    Sets the PCM sample rate for a channel.
 *
 *    Values for @rate are clamped to a range of 4000 Khz through 48000 Khz,
 *    due to hardware constraints.
 */

static int via_set_rate (struct ac97_codec *ac97,
                   struct via_channel *chan, unsigned rate)
{
      struct via_info *card = ac97->private_data;
      int rate_reg;
      u32 dacp;
      u32 mast_vol, phone_vol, mono_vol, pcm_vol;
      u32 mute_vol = 0x8000;  /* The mute volume? -- Seems to work! */

      DPRINTK ("ENTER, rate = %d\n", rate);

      if (chan->rate == rate)
            goto out;
      if (card->locked_rate) {
            chan->rate = 48000;
            goto out;
      }

      if (rate > 48000)       rate = 48000;
      if (rate < 4000)        rate = 4000;

      rate_reg = chan->is_record ? AC97_PCM_LR_ADC_RATE :
                      AC97_PCM_FRONT_DAC_RATE;

      /* Save current state */
      dacp=via_ac97_read_reg(ac97, AC97_POWER_CONTROL);
      mast_vol = via_ac97_read_reg(ac97, AC97_MASTER_VOL_STEREO);
      mono_vol = via_ac97_read_reg(ac97, AC97_MASTER_VOL_MONO);
      phone_vol = via_ac97_read_reg(ac97, AC97_HEADPHONE_VOL);
      pcm_vol = via_ac97_read_reg(ac97, AC97_PCMOUT_VOL);
      /* Mute - largely reduces popping */
      via_ac97_write_reg(ac97, AC97_MASTER_VOL_STEREO, mute_vol);
      via_ac97_write_reg(ac97, AC97_MASTER_VOL_MONO, mute_vol);
      via_ac97_write_reg(ac97, AC97_HEADPHONE_VOL, mute_vol);
            via_ac97_write_reg(ac97, AC97_PCMOUT_VOL, mute_vol);
      /* Power down the DAC */
      via_ac97_write_reg(ac97, AC97_POWER_CONTROL, dacp|0x0200);

        /* Set new rate */
      via_ac97_write_reg (ac97, rate_reg, rate);

      /* Power DAC back up */
      via_ac97_write_reg(ac97, AC97_POWER_CONTROL, dacp);
      udelay (200); /* reduces popping */

      /* Restore volumes */
      via_ac97_write_reg(ac97, AC97_MASTER_VOL_STEREO, mast_vol);
      via_ac97_write_reg(ac97, AC97_MASTER_VOL_MONO, mono_vol);
      via_ac97_write_reg(ac97, AC97_HEADPHONE_VOL, phone_vol);
      via_ac97_write_reg(ac97, AC97_PCMOUT_VOL, pcm_vol);

      /* the hardware might return a value different than what we
       * passed to it, so read the rate value back from hardware
       * to see what we came up with
       */
      chan->rate = via_ac97_read_reg (ac97, rate_reg);

      if (chan->rate == 0) {
            card->locked_rate = 1;
            chan->rate = 48000;
            printk (KERN_WARNING PFX "Codec rate locked at 48Khz\n");
      }

out:
      DPRINTK ("EXIT, returning rate %d Hz\n", chan->rate);
      return chan->rate;
}


/****************************************************************
 *
 * Channel-specific operations
 *
 *
 */


/**
 *    via_chan_init_defaults - Initialize a struct via_channel
 *    @card: Private audio chip info
 *    @chan: Channel to be initialized
 *
 *    Zero @chan, and then set all static defaults for the structure.
 */

static void via_chan_init_defaults (struct via_info *card, struct via_channel *chan)
{
      memset (chan, 0, sizeof (*chan));

      if(card->intmask)
            chan->intmask = 0x23;   /* Turn on the IRQ bits */
            
      if (chan == &card->ch_out) {
            chan->name = "PCM-OUT";
            if(card->sixchannel)
            {
                  chan->iobase = card->baseaddr + VIA_BASE0_MULTI_OUT_CHAN;
                  chan->is_multi = 1;
                  DPRINTK("Using multichannel for pcm out\n");
            }
            else
                  chan->iobase = card->baseaddr + VIA_BASE0_PCM_OUT_CHAN;
      } else if (chan == &card->ch_in) {
            chan->name = "PCM-IN";
            chan->iobase = card->baseaddr + VIA_BASE0_PCM_IN_CHAN;
            chan->is_record = 1;
      } else if (chan == &card->ch_fm) {
            chan->name = "PCM-OUT-FM";
            chan->iobase = card->baseaddr + VIA_BASE0_FM_OUT_CHAN;
      } else {
            BUG();
      }

      init_waitqueue_head (&chan->wait);

      chan->pcm_fmt = VIA_PCM_FMT_MASK;
      chan->is_enabled = 1;

      chan->frag_number = 0;
        chan->frag_size = 0;
      atomic_set(&chan->n_frags, 0);
      atomic_set (&chan->hw_ptr, 0);
}

/**
 *      via_chan_init - Initialize PCM channel
 *      @card: Private audio chip info
 *      @chan: Channel to be initialized
 *
 *      Performs some of the preparations necessary to begin
 *      using a PCM channel.
 *
 *      Currently the preparations consist of
 *      setting the PCM channel to a known state.
 */


static void via_chan_init (struct via_info *card, struct via_channel *chan)
{

        DPRINTK ("ENTER\n");

      /* bzero channel structure, and init members to defaults */
        via_chan_init_defaults (card, chan);

        /* stop any existing channel output */
        via_chan_clear (card, chan);
        via_chan_status_clear (chan->iobase);
        via_chan_pcm_fmt (chan, 1);

      DPRINTK ("EXIT\n");
}

/**
 *    via_chan_buffer_init - Initialize PCM channel buffer
 *    @card: Private audio chip info
 *    @chan: Channel to be initialized
 *
 *    Performs some of the preparations necessary to begin
 *    using a PCM channel.
 *
 *    Currently the preparations include allocating the
 *    scatter-gather DMA table and buffers,
 *    and passing the
 *    address of the DMA table to the hardware.
 *
 *    Note that special care is taken when passing the
 *    DMA table address to hardware, because it was found
 *    during driver development that the hardware did not
 *    always "take" the address.
 */

static int via_chan_buffer_init (struct via_info *card, struct via_channel *chan)
{
      int page, offset;
      int i;

      DPRINTK ("ENTER\n");


      chan->intmask = 0;
      if(card->intmask)
            chan->intmask = 0x23;   /* Turn on the IRQ bits */
            
      if (chan->sgtable != NULL) {
            DPRINTK ("EXIT\n");
            return 0;
      }

      /* alloc DMA-able memory for scatter-gather table */
      chan->sgtable = pci_alloc_consistent (card->pdev,
            (sizeof (struct via_sgd_table) * chan->frag_number),
            &chan->sgt_handle);
      if (!chan->sgtable) {
            printk (KERN_ERR PFX "DMA table alloc fail, aborting\n");
            DPRINTK ("EXIT\n");
            return -ENOMEM;
      }

      memset ((void*)chan->sgtable, 0,
            (sizeof (struct via_sgd_table) * chan->frag_number));

      /* alloc DMA-able memory for scatter-gather buffers */

      chan->page_number = (chan->frag_number * chan->frag_size) / PAGE_SIZE +
                      (((chan->frag_number * chan->frag_size) % PAGE_SIZE) ? 1 : 0);

      for (i = 0; i < chan->page_number; i++) {
            chan->pgtbl[i].cpuaddr = pci_alloc_consistent (card->pdev, PAGE_SIZE,
                                    &chan->pgtbl[i].handle);

            if (!chan->pgtbl[i].cpuaddr) {
                  chan->page_number = i;
                  goto err_out_nomem;
            }

#ifndef VIA_NDEBUG
                memset (chan->pgtbl[i].cpuaddr, 0xBC, chan->frag_size);
#endif

#if 1
                DPRINTK ("dmabuf_pg #%d (h=%lx, v2p=%lx, a=%p)\n",
                  i, (long)chan->pgtbl[i].handle,
                  virt_to_phys(chan->pgtbl[i].cpuaddr),
                  chan->pgtbl[i].cpuaddr);
#endif
      }

      for (i = 0; i < chan->frag_number; i++) {

            page = i / (PAGE_SIZE / chan->frag_size);
            offset = (i % (PAGE_SIZE / chan->frag_size)) * chan->frag_size;

            chan->sgtable[i].count = cpu_to_le32 (chan->frag_size | VIA_FLAG);
            chan->sgtable[i].addr = cpu_to_le32 (chan->pgtbl[page].handle + offset);

#if 1
            DPRINTK ("dmabuf #%d (32(h)=%lx)\n",
                   i,
                   (long)chan->sgtable[i].addr);
#endif
      }

      /* overwrite the last buffer information */
      chan->sgtable[chan->frag_number - 1].count = cpu_to_le32 (chan->frag_size | VIA_EOL);

      /* set location of DMA-able scatter-gather info table */
      DPRINTK ("outl (0x%X, 0x%04lX)\n",
            chan->sgt_handle, chan->iobase + VIA_PCM_TABLE_ADDR);

      via_ac97_wait_idle (card);
      outl (chan->sgt_handle, chan->iobase + VIA_PCM_TABLE_ADDR);
      udelay (20);
      via_ac97_wait_idle (card);
      /* load no rate adaption, stereo 16bit, set up ring slots */
      if(card->sixchannel)
      {
            if(!chan->is_multi)
            {
                  outl (0xFFFFF | (0x3 << 20) | (chan->frag_number << 24), chan->iobase + VIA_PCM_STOPRATE);
                  udelay (20);
                  via_ac97_wait_idle (card);
            }
      }

      DPRINTK ("inl (0x%lX) = %x\n",
            chan->iobase + VIA_PCM_TABLE_ADDR,
            inl(chan->iobase + VIA_PCM_TABLE_ADDR));

      DPRINTK ("EXIT\n");
      return 0;

err_out_nomem:
      printk (KERN_ERR PFX "DMA buffer alloc fail, aborting\n");
      via_chan_buffer_free (card, chan);
      DPRINTK ("EXIT\n");
      return -ENOMEM;
}


/**
 *    via_chan_free - Release a PCM channel
 *    @card: Private audio chip info
 *    @chan: Channel to be released
 *
 *    Performs all the functions necessary to clean up
 *    an initialized channel.
 *
 *    Currently these functions include disabled any
 *    active DMA operations, setting the PCM channel
 *    back to a known state, and releasing any allocated
 *    sound buffers.
 */

static void via_chan_free (struct via_info *card, struct via_channel *chan)
{
      DPRINTK ("ENTER\n");

      spin_lock_irq (&card->lock);

      /* stop any existing channel output */
      via_chan_status_clear (chan->iobase);
      via_chan_stop (chan->iobase);
      via_chan_status_clear (chan->iobase);

      spin_unlock_irq (&card->lock);

      synchronize_irq(card->pdev->irq);

      DPRINTK ("EXIT\n");
}

static void via_chan_buffer_free (struct via_info *card, struct via_channel *chan)
{
      int i;

        DPRINTK ("ENTER\n");

      /* zero location of DMA-able scatter-gather info table */
      via_ac97_wait_idle(card);
      outl (0, chan->iobase + VIA_PCM_TABLE_ADDR);

      for (i = 0; i < chan->page_number; i++)
            if (chan->pgtbl[i].cpuaddr) {
                  pci_free_consistent (card->pdev, PAGE_SIZE,
                                   chan->pgtbl[i].cpuaddr,
                                   chan->pgtbl[i].handle);
                  chan->pgtbl[i].cpuaddr = NULL;
                  chan->pgtbl[i].handle = 0;
            }

      chan->page_number = 0;

      if (chan->sgtable) {
            pci_free_consistent (card->pdev,
                  (sizeof (struct via_sgd_table) * chan->frag_number),
                  (void*)chan->sgtable, chan->sgt_handle);
            chan->sgtable = NULL;
      }

      DPRINTK ("EXIT\n");
}


/**
 *    via_chan_pcm_fmt - Update PCM channel settings
 *    @chan: Channel to be updated
 *    @reset: Boolean.  If non-zero, channel will be reset
 *          to 8-bit mono mode.
 *
 *    Stores the settings of the current PCM format,
 *    8-bit or 16-bit, and mono/stereo, into the
 *    hardware settings for the specified channel.
 *    If @reset is non-zero, the channel is reset
 *    to 8-bit mono mode.  Otherwise, the channel
 *    is set to the values stored in the channel
 *    information struct @chan.
 */

static void via_chan_pcm_fmt (struct via_channel *chan, int reset)
{
      DPRINTK ("ENTER, pcm_fmt=0x%02X, reset=%s\n",
             chan->pcm_fmt, reset ? "yes" : "no");

      assert (chan != NULL);

      if (reset)
      {
            /* reset to 8-bit mono mode */
            chan->pcm_fmt = 0;
            chan->channels = 1;
      }

      /* enable interrupts on FLAG and EOL */
      chan->pcm_fmt |= VIA_CHAN_TYPE_MASK;

      /* if we are recording, enable recording fifo bit */
      if (chan->is_record)
            chan->pcm_fmt |= VIA_PCM_REC_FIFO;
      /* set interrupt select bits where applicable (PCM in & out channels) */
      if (!chan->is_record)
            chan->pcm_fmt |= VIA_CHAN_TYPE_INT_SELECT;
      
      DPRINTK("SET FMT - %02x %02x\n", chan->intmask , chan->is_multi);
      
      if(chan->intmask)
      {
            u32 m;

            /*
             *    Channel 0x4 is up to 6 x 16bit and has to be
             *    programmed differently 
             */
                        
            if(chan->is_multi)
            {
                  u8 c = 0;
                  
                  /*
                   *    Load the type bit for num channels
                   *    and 8/16bit
                   */
                   
                  if(chan->pcm_fmt & VIA_PCM_FMT_16BIT)
                        c = 1 << 7;
                  if(chan->pcm_fmt & VIA_PCM_FMT_STEREO)
                        c |= (2<<4);
                  else
                        c |= (1<<4);
                        
                  outb(c, chan->iobase + VIA_PCM_TYPE);
                  
                  /*
                   *    Set the channel steering
                   *    Mono
                   *          Channel 0 to slot 3
                   *          Channel 0 to slot 4
                   *    Stereo
                   *          Channel 0 to slot 3
                   *          Channel 1 to slot 4
                   */
                   
                  switch(chan->channels)
                  {
                        case 1:
                              outl(0xFF000000 | (1<<0) | (1<<4) , chan->iobase + VIA_PCM_STOPRATE);
                              break;
                        case 2:
                              outl(0xFF000000 | (1<<0) | (2<<4) , chan->iobase + VIA_PCM_STOPRATE);
                              break;
                        case 4:
                              outl(0xFF000000 | (1<<0) | (2<<4) | (3<<8) | (4<<12), chan->iobase + VIA_PCM_STOPRATE);
                              break;
                        case 6:
                              outl(0xFF000000 | (1<<0) | (2<<4) | (5<<8) | (6<<12) | (3<<16) | (4<<20), chan->iobase + VIA_PCM_STOPRATE);
                              break;
                  }                       
            }
            else
            {
                  /*
                   *    New style, turn off channel volume
                   *    control, set bits in the right register
                   */   
                  outb(0x0, chan->iobase + VIA_PCM_LEFTVOL);
                  outb(0x0, chan->iobase + VIA_PCM_RIGHTVOL);

                  m = inl(chan->iobase + VIA_PCM_STOPRATE);
                  m &= ~(3<<20);
                  if(chan->pcm_fmt & VIA_PCM_FMT_STEREO)
                        m |= (1 << 20);
                  if(chan->pcm_fmt & VIA_PCM_FMT_16BIT)
                        m |= (1 << 21);
                  outl(m, chan->iobase + VIA_PCM_STOPRATE);
            }           
      }
      else
            outb (chan->pcm_fmt, chan->iobase + VIA_PCM_TYPE);


      DPRINTK ("EXIT, pcm_fmt = 0x%02X, reg = 0x%02X\n",
             chan->pcm_fmt,
             inb (chan->iobase + VIA_PCM_TYPE));
}


/**
 *    via_chan_clear - Stop DMA channel operation, and reset pointers
 *    @card: the chip to accessed
 *    @chan: Channel to be cleared
 *
 *    Call via_chan_stop to halt DMA operations, and then resets
 *    all software pointers which track DMA operation.
 */

static void via_chan_clear (struct via_info *card, struct via_channel *chan)
{
      DPRINTK ("ENTER\n");
      via_chan_stop (chan->iobase);
      via_chan_buffer_free(card, chan);
      chan->is_active = 0;
      chan->is_mapped = 0;
      chan->is_enabled = 1;
      chan->slop_len = 0;
      chan->sw_ptr = 0;
      chan->n_irqs = 0;
      atomic_set (&chan->hw_ptr, 0);
      DPRINTK ("EXIT\n");
}


/**
 *    via_chan_set_speed - Set PCM sample rate for given channel
 *    @card: Private info for specified board
 *    @chan: Channel whose sample rate will be adjusted
 *    @val: New sample rate, in Khz
 *
 *    Helper function for the %SNDCTL_DSP_SPEED ioctl.  OSS semantics
 *    demand that all audio operations halt (if they are not already
 *    halted) when the %SNDCTL_DSP_SPEED is given.
 *
 *    This function halts all audio operations for the given channel
 *    @chan, and then calls via_set_rate to set the audio hardware
 *    to the new rate.
 */

static int via_chan_set_speed (struct via_info *card,
                         struct via_channel *chan, int val)
{
      DPRINTK ("ENTER, requested rate = %d\n", val);

      via_chan_clear (card, chan);

      val = via_set_rate (card->ac97, chan, val);

      DPRINTK ("EXIT, returning %d\n", val);
      return val;
}


/**
 *    via_chan_set_fmt - Set PCM sample size for given channel
 *    @card: Private info for specified board
 *    @chan: Channel whose sample size will be adjusted
 *    @val: New sample size, use the %AFMT_xxx constants
 *
 *    Helper function for the %SNDCTL_DSP_SETFMT ioctl.  OSS semantics
 *    demand that all audio operations halt (if they are not already
 *    halted) when the %SNDCTL_DSP_SETFMT is given.
 *
 *    This function halts all audio operations for the given channel
 *    @chan, and then calls via_chan_pcm_fmt to set the audio hardware
 *    to the new sample size, either 8-bit or 16-bit.
 */

static int via_chan_set_fmt (struct via_info *card,
                       struct via_channel *chan, int val)
{
      DPRINTK ("ENTER, val=%s\n",
             val == AFMT_U8 ? "AFMT_U8" :
             val == AFMT_S16_LE ? "AFMT_S16_LE" :
             "unknown");

      via_chan_clear (card, chan);

      assert (val != AFMT_QUERY); /* this case is handled elsewhere */

      switch (val) {
      case AFMT_S16_LE:
            if ((chan->pcm_fmt & VIA_PCM_FMT_16BIT) == 0) {
                  chan->pcm_fmt |= VIA_PCM_FMT_16BIT;
                  via_chan_pcm_fmt (chan, 0);
            }
            break;

      case AFMT_U8:
            if (chan->pcm_fmt & VIA_PCM_FMT_16BIT) {
                  chan->pcm_fmt &= ~VIA_PCM_FMT_16BIT;
                  via_chan_pcm_fmt (chan, 0);
            }
            break;

      default:
            DPRINTK ("unknown AFMT: 0x%X\n", val);
            val = AFMT_S16_LE;
      }

      DPRINTK ("EXIT\n");
      return val;
}


/**
 *    via_chan_set_stereo - Enable or disable stereo for a DMA channel
 *    @card: Private info for specified board
 *    @chan: Channel whose stereo setting will be adjusted
 *    @val: New sample size, use the %AFMT_xxx constants
 *
 *    Helper function for the %SNDCTL_DSP_CHANNELS and %SNDCTL_DSP_STEREO ioctls.  OSS semantics
 *    demand that all audio operations halt (if they are not already
 *    halted) when %SNDCTL_DSP_CHANNELS or SNDCTL_DSP_STEREO is given.
 *
 *    This function halts all audio operations for the given channel
 *    @chan, and then calls via_chan_pcm_fmt to set the audio hardware
 *    to enable or disable stereo.
 */

static int via_chan_set_stereo (struct via_info *card,
                          struct via_channel *chan, int val)
{
      DPRINTK ("ENTER, channels = %d\n", val);

      via_chan_clear (card, chan);

      switch (val) {

      /* mono */
      case 1:
            chan->pcm_fmt &= ~VIA_PCM_FMT_STEREO;
            chan->channels = 1;
            via_chan_pcm_fmt (chan, 0);
            break;

      /* stereo */
      case 2:
            chan->pcm_fmt |= VIA_PCM_FMT_STEREO;
            chan->channels = 2;
            via_chan_pcm_fmt (chan, 0);
            break;

      case 4:
      case 6:
            if(chan->is_multi)
            {
                  chan->pcm_fmt |= VIA_PCM_FMT_STEREO;
                  chan->channels = val;
                  break;
            }
      /* unknown */
      default:
            val = -EINVAL;
            break;
      }

      DPRINTK ("EXIT, returning %d\n", val);
      return val;
}

static int via_chan_set_buffering (struct via_info *card,
                                struct via_channel *chan, int val)
{
      int shift;

        DPRINTK ("ENTER\n");

      /* in both cases the buffer cannot be changed */
      if (chan->is_active || chan->is_mapped) {
            DPRINTK ("EXIT\n");
            return -EINVAL;
      }

      /* called outside SETFRAGMENT */
      /* set defaults or do nothing */
      if (val < 0) {

            if (chan->frag_size && chan->frag_number)
                  goto out;

            DPRINTK ("\n");

            chan->frag_size = (VIA_DEFAULT_FRAG_TIME * chan->rate * chan->channels
                           * ((chan->pcm_fmt & VIA_PCM_FMT_16BIT) ? 2 : 1)) / 1000 - 1;

            shift = 0;
            while (chan->frag_size) {
                  chan->frag_size >>= 1;
                  shift++;
            }
            chan->frag_size = 1 << shift;

            chan->frag_number = (VIA_DEFAULT_BUFFER_TIME / VIA_DEFAULT_FRAG_TIME);

            DPRINTK ("setting default values %d %d\n", chan->frag_size, chan->frag_number);
      } else {
            chan->frag_size = 1 << (val & 0xFFFF);
            chan->frag_number = (val >> 16) & 0xFFFF;

            DPRINTK ("using user values %d %d\n", chan->frag_size, chan->frag_number);
      }

      /* quake3 wants frag_number to be a power of two */
      shift = 0;
      while (chan->frag_number) {
            chan->frag_number >>= 1;
            shift++;
      }
      chan->frag_number = 1 << shift;

      if (chan->frag_size > VIA_MAX_FRAG_SIZE)
            chan->frag_size = VIA_MAX_FRAG_SIZE;
      else if (chan->frag_size < VIA_MIN_FRAG_SIZE)
            chan->frag_size = VIA_MIN_FRAG_SIZE;

      if (chan->frag_number < VIA_MIN_FRAG_NUMBER)
                chan->frag_number = VIA_MIN_FRAG_NUMBER;
        if (chan->frag_number > VIA_MAX_FRAG_NUMBER)
            chan->frag_number = VIA_MAX_FRAG_NUMBER;

      if ((chan->frag_number * chan->frag_size) / PAGE_SIZE > VIA_MAX_BUFFER_DMA_PAGES)
            chan->frag_number = (VIA_MAX_BUFFER_DMA_PAGES * PAGE_SIZE) / chan->frag_size;

out:
      if (chan->is_record)
            atomic_set (&chan->n_frags, 0);
      else
            atomic_set (&chan->n_frags, chan->frag_number);

      DPRINTK ("EXIT\n");

      return 0;
}

#ifdef VIA_CHAN_DUMP_BUFS
/**
 *    via_chan_dump_bufs - Display DMA table contents
 *    @chan: Channel whose DMA table will be displayed
 *
 *    Debugging function which displays the contents of the
 *    scatter-gather DMA table for the given channel @chan.
 */

static void via_chan_dump_bufs (struct via_channel *chan)
{
      int i;

      for (i = 0; i < chan->frag_number; i++) {
            DPRINTK ("#%02d: addr=%x, count=%u, flag=%d, eol=%d\n",
                   i, chan->sgtable[i].addr,
                   chan->sgtable[i].count & 0x00FFFFFF,
                   chan->sgtable[i].count & VIA_FLAG ? 1 : 0,
                   chan->sgtable[i].count & VIA_EOL ? 1 : 0);
      }
      DPRINTK ("buf_in_use = %d, nextbuf = %d\n",
             atomic_read (&chan->buf_in_use),
             atomic_read (&chan->sw_ptr));
}
#endif /* VIA_CHAN_DUMP_BUFS */


/**
 *    via_chan_flush_frag - Flush partially-full playback buffer to hardware
 *    @chan: Channel whose DMA table will be flushed
 *
 *    Flushes partially-full playback buffer to hardware.
 */

static void via_chan_flush_frag (struct via_channel *chan)
{
      DPRINTK ("ENTER\n");

      assert (chan->slop_len > 0);

      if (chan->sw_ptr == (chan->frag_number - 1))
            chan->sw_ptr = 0;
      else
            chan->sw_ptr++;

      chan->slop_len = 0;

      assert (atomic_read (&chan->n_frags) > 0);
      atomic_dec (&chan->n_frags);

      DPRINTK ("EXIT\n");
}



/**
 *    via_chan_maybe_start - Initiate audio hardware DMA operation
 *    @chan: Channel whose DMA is to be started
 *
 *    Initiate DMA operation, if the DMA engine for the given
 *    channel @chan is not already active.
 */

static inline void via_chan_maybe_start (struct via_channel *chan)
{
      assert (chan->is_active == sg_active(chan->iobase));

      DPRINTK ("MAYBE START %s\n", chan->name);
      if (!chan->is_active && chan->is_enabled) {
            chan->is_active = 1;
            sg_begin (chan);
            DPRINTK ("starting channel %s\n", chan->name);
      }
}


/****************************************************************
 *
 * Interface to ac97-codec module
 *
 *
 */

/**
 *    via_ac97_wait_idle - Wait until AC97 codec is not busy
 *    @card: Private info for specified board
 *
 *    Sleep until the AC97 codec is no longer busy.
 *    Returns the final value read from the SGD
 *    register being polled.
 */

static u8 via_ac97_wait_idle (struct via_info *card)
{
      u8 tmp8;
      int counter = VIA_COUNTER_LIMIT;

      DPRINTK ("ENTER/EXIT\n");

      assert (card != NULL);
      assert (card->pdev != NULL);

      do {
            udelay (15);

            tmp8 = inb (card->baseaddr + 0x83);
      } while ((tmp8 & VIA_CR83_BUSY) && (counter-- > 0));

      if (tmp8 & VIA_CR83_BUSY)
            printk (KERN_WARNING PFX "timeout waiting on AC97 codec\n");
      return tmp8;
}


/**
 *    via_ac97_read_reg - Read AC97 standard register
 *    @codec: Pointer to generic AC97 codec info
 *    @reg: Index of AC97 register to be read
 *
 *    Read the value of a single AC97 codec register,
 *    as defined by the Intel AC97 specification.
 *
 *    Defines the standard AC97 read-register operation
 *    required by the kernel's ac97_codec interface.
 *
 *    Returns the 16-bit value stored in the specified
 *    register.
 */

static u16 via_ac97_read_reg (struct ac97_codec *codec, u8 reg)
{
      unsigned long data;
      struct via_info *card;
      int counter;

      DPRINTK ("ENTER\n");

      assert (codec != NULL);
      assert (codec->private_data != NULL);

      card = codec->private_data;
      
      spin_lock(&card->ac97_lock);

      /* Every time we write to register 80 we cause a transaction.
         The only safe way to clear the valid bit is to write it at
         the same time as the command */
      data = (reg << 16) | VIA_CR80_READ | VIA_CR80_VALID;

      outl (data, card->baseaddr + VIA_BASE0_AC97_CTRL);
      udelay (20);

      for (counter = VIA_COUNTER_LIMIT; counter > 0; counter--) {
            udelay (1);
            if ((((data = inl(card->baseaddr + VIA_BASE0_AC97_CTRL)) &
                  (VIA_CR80_VALID|VIA_CR80_BUSY)) == VIA_CR80_VALID))
                  goto out;
      }

      printk (KERN_WARNING PFX "timeout while reading AC97 codec (0x%lX)\n", data);
      goto err_out;

out:
      /* Once the valid bit has become set, we must wait a complete AC97
         frame before the data has settled. */
      udelay(25);
      data = (unsigned long) inl (card->baseaddr + VIA_BASE0_AC97_CTRL);

      outb (0x02, card->baseaddr + 0x83);

      if (((data & 0x007F0000) >> 16) == reg) {
            DPRINTK ("EXIT, success, data=0x%lx, retval=0x%lx\n",
                   data, data & 0x0000FFFF);
            spin_unlock(&card->ac97_lock);
            return data & 0x0000FFFF;
      }

      printk (KERN_WARNING "via82cxxx_audio: not our index: reg=0x%x, newreg=0x%lx\n",
            reg, ((data & 0x007F0000) >> 16));

err_out:
      spin_unlock(&card->ac97_lock);
      DPRINTK ("EXIT, returning 0\n");
      return 0;
}


/**
 *    via_ac97_write_reg - Write AC97 standard register
 *    @codec: Pointer to generic AC97 codec info
 *    @reg: Index of AC97 register to be written
 *    @value: Value to be written to AC97 register
 *
 *    Write the value of a single AC97 codec register,
 *    as defined by the Intel AC97 specification.
 *
 *    Defines the standard AC97 write-register operation
 *    required by the kernel's ac97_codec interface.
 */

static void via_ac97_write_reg (struct ac97_codec *codec, u8 reg, u16 value)
{
      u32 data;
      struct via_info *card;
      int counter;

      DPRINTK ("ENTER\n");

      assert (codec != NULL);
      assert (codec->private_data != NULL);

      card = codec->private_data;

      spin_lock(&card->ac97_lock);
      
      data = (reg << 16) + value;
      outl (data, card->baseaddr + VIA_BASE0_AC97_CTRL);
      udelay (10);

      for (counter = VIA_COUNTER_LIMIT; counter > 0; counter--) {
            if ((inb (card->baseaddr + 0x83) & VIA_CR83_BUSY) == 0)
                  goto out;

            udelay (15);
      }

      printk (KERN_WARNING PFX "timeout after AC97 codec write (0x%X, 0x%X)\n", reg, value);

out:
      spin_unlock(&card->ac97_lock);
      DPRINTK ("EXIT\n");
}


static int via_mixer_open (struct inode *inode, struct file *file)
{
      int minor = iminor(inode);
      struct via_info *card;
      struct pci_dev *pdev = NULL;
      struct pci_driver *drvr;

      DPRINTK ("ENTER\n");

      while ((pdev = pci_find_device(PCI_ANY_ID, PCI_ANY_ID, pdev)) != NULL) {
            drvr = pci_dev_driver (pdev);
            if (drvr == &via_driver) {
                  assert (pci_get_drvdata (pdev) != NULL);

                  card = pci_get_drvdata (pdev);
                  if (card->ac97->dev_mixer == minor)
                        goto match;
            }
      }

      DPRINTK ("EXIT, returning -ENODEV\n");
      return -ENODEV;

match:
      file->private_data = card->ac97;

      DPRINTK ("EXIT, returning 0\n");
      return nonseekable_open(inode, file);
}

static int via_mixer_ioctl (struct inode *inode, struct file *file, unsigned int cmd,
                      unsigned long arg)
{
      struct ac97_codec *codec = file->private_data;
      struct via_info *card;
      int nonblock = (file->f_flags & O_NONBLOCK);
      int rc;

      DPRINTK ("ENTER\n");

      assert (codec != NULL);
      card = codec->private_data;
      assert (card != NULL);

      rc = via_syscall_down (card, nonblock);
      if (rc) goto out;
      
#if 0
      /*
       *    Intercept volume control on 8233 and 8235
       */
      if(card->volume)
      {
            switch(cmd)
            {
                  case SOUND_MIXER_READ_VOLUME:
                        return card->mixer_vol;
                  case SOUND_MIXER_WRITE_VOLUME:
                  {
                        int v;
                        if(get_user(v, (int *)arg))
                        {
                              rc = -EFAULT;
                              goto out;
                        }
                        card->mixer_vol = v;
                  }
            }
      }           
#endif
      rc = codec->mixer_ioctl(codec, cmd, arg);

      mutex_unlock(&card->syscall_mutex);

out:
      DPRINTK ("EXIT, returning %d\n", rc);
      return rc;
}


static struct file_operations via_mixer_fops = {
      .owner            = THIS_MODULE,
      .open       = via_mixer_open,
      .llseek           = no_llseek,
      .ioctl            = via_mixer_ioctl,
};


static int __devinit via_ac97_reset (struct via_info *card)
{
      struct pci_dev *pdev = card->pdev;
      u8 tmp8;
      u16 tmp16;

      DPRINTK ("ENTER\n");

      assert (pdev != NULL);

#ifndef NDEBUG
      {
            u8 r40,r41,r42,r43,r44,r48;
            pci_read_config_byte (card->pdev, 0x40, &r40);
            pci_read_config_byte (card->pdev, 0x41, &r41);
            pci_read_config_byte (card->pdev, 0x42, &r42);
            pci_read_config_byte (card->pdev, 0x43, &r43);
            pci_read_config_byte (card->pdev, 0x44, &r44);
            pci_read_config_byte (card->pdev, 0x48, &r48);
            DPRINTK ("PCI config: %02X %02X %02X %02X %02X %02X\n",
                  r40,r41,r42,r43,r44,r48);

            spin_lock_irq (&card->lock);
            DPRINTK ("regs==%02X %02X %02X %08X %08X %08X %08X\n",
                   inb (card->baseaddr + 0x00),
                   inb (card->baseaddr + 0x01),
                   inb (card->baseaddr + 0x02),
                   inl (card->baseaddr + 0x04),
                   inl (card->baseaddr + 0x0C),
                   inl (card->baseaddr + 0x80),
                   inl (card->baseaddr + 0x84));
            spin_unlock_irq (&card->lock);

      }
#endif

        /*
         * Reset AC97 controller: enable, disable, enable,
         * pausing after each command for good luck.  Only
       * do this if the codec is not ready, because it causes
       * loud pops and such due to such a hard codec reset.
         */
      pci_read_config_byte (pdev, VIA_ACLINK_STATUS, &tmp8);
      if ((tmp8 & VIA_CR40_AC97_READY) == 0) {
            pci_write_config_byte (pdev, VIA_ACLINK_CTRL,
                               VIA_CR41_AC97_ENABLE |
                               VIA_CR41_AC97_RESET |
                               VIA_CR41_AC97_WAKEUP);
            udelay (100);

            pci_write_config_byte (pdev, VIA_ACLINK_CTRL, 0);
            udelay (100);

            pci_write_config_byte (pdev, VIA_ACLINK_CTRL,
                               VIA_CR41_AC97_ENABLE |
                               VIA_CR41_PCM_ENABLE |
                               VIA_CR41_VRA | VIA_CR41_AC97_RESET);
            udelay (100);
      }

      /* Make sure VRA is enabled, in case we didn't do a
       * complete codec reset, above
       */
      pci_read_config_byte (pdev, VIA_ACLINK_CTRL, &tmp8);
      if (((tmp8 & VIA_CR41_VRA) == 0) ||
          ((tmp8 & VIA_CR41_AC97_ENABLE) == 0) ||
          ((tmp8 & VIA_CR41_PCM_ENABLE) == 0) ||
          ((tmp8 & VIA_CR41_AC97_RESET) == 0)) {
            pci_write_config_byte (pdev, VIA_ACLINK_CTRL,
                               VIA_CR41_AC97_ENABLE |
                               VIA_CR41_PCM_ENABLE |
                               VIA_CR41_VRA | VIA_CR41_AC97_RESET);
            udelay (100);
      }

      if(card->legacy)
      {
#if 0 /* this breaks on K7M */
            /* disable legacy stuff */
            pci_write_config_byte (pdev, 0x42, 0x00);
            udelay(10);
#endif

            /* route FM trap to IRQ, disable FM trap */
            pci_write_config_byte (pdev, 0x48, 0x05);
            udelay(10);
      }
      
      /* disable all codec GPI interrupts */
      outl (0, pci_resource_start (pdev, 0) + 0x8C);

      /* WARNING: this line is magic.  Remove this
       * and things break. */
      /* enable variable rate */
      tmp16 = via_ac97_read_reg (card->ac97, AC97_EXTENDED_STATUS);
      if ((tmp16 & 1) == 0)
            via_ac97_write_reg (card->ac97, AC97_EXTENDED_STATUS, tmp16 | 1);

      DPRINTK ("EXIT, returning 0\n");
      return 0;
}


static void via_ac97_codec_wait (struct ac97_codec *codec)
{
      assert (codec->private_data != NULL);
      via_ac97_wait_idle (codec->private_data);
}


static int __devinit via_ac97_init (struct via_info *card)
{
      int rc;
      u16 tmp16;

      DPRINTK ("ENTER\n");

      assert (card != NULL);

      card->ac97 = ac97_alloc_codec();
      if(card->ac97 == NULL)
            return -ENOMEM;
            
      card->ac97->private_data = card;
      card->ac97->codec_read = via_ac97_read_reg;
      card->ac97->codec_write = via_ac97_write_reg;
      card->ac97->codec_wait = via_ac97_codec_wait;

      card->ac97->dev_mixer = register_sound_mixer (&via_mixer_fops, -1);
      if (card->ac97->dev_mixer < 0) {
            printk (KERN_ERR PFX "unable to register AC97 mixer, aborting\n");
            DPRINTK ("EXIT, returning -EIO\n");
            ac97_release_codec(card->ac97);
            return -EIO;
      }

      rc = via_ac97_reset (card);
      if (rc) {
            printk (KERN_ERR PFX "unable to reset AC97 codec, aborting\n");
            goto err_out;
      }
      
      mdelay(10);
      
      if (ac97_probe_codec (card->ac97) == 0) {
            printk (KERN_ERR PFX "unable to probe AC97 codec, aborting\n");
            rc = -EIO;
            goto err_out;
      }

      /* enable variable rate */
      tmp16 = via_ac97_read_reg (card->ac97, AC97_EXTENDED_STATUS);
      via_ac97_write_reg (card->ac97, AC97_EXTENDED_STATUS, tmp16 | 1);

      /*
       * If we cannot enable VRA, we have a locked-rate codec.
       * We try again to enable VRA before assuming so, however.
       */
      tmp16 = via_ac97_read_reg (card->ac97, AC97_EXTENDED_STATUS);
      if ((tmp16 & 1) == 0) {
            via_ac97_write_reg (card->ac97, AC97_EXTENDED_STATUS, tmp16 | 1);
            tmp16 = via_ac97_read_reg (card->ac97, AC97_EXTENDED_STATUS);
            if ((tmp16 & 1) == 0) {
                  card->locked_rate = 1;
                  printk (KERN_WARNING PFX "Codec rate locked at 48Khz\n");
            }
      }

      DPRINTK ("EXIT, returning 0\n");
      return 0;

err_out:
      unregister_sound_mixer (card->ac97->dev_mixer);
      DPRINTK ("EXIT, returning %d\n", rc);
      ac97_release_codec(card->ac97);
      return rc;
}


static void via_ac97_cleanup (struct via_info *card)
{
      DPRINTK ("ENTER\n");

      assert (card != NULL);
      assert (card->ac97->dev_mixer >= 0);

      unregister_sound_mixer (card->ac97->dev_mixer);
      ac97_release_codec(card->ac97);

      DPRINTK ("EXIT\n");
}



/****************************************************************
 *
 * Interrupt-related code
 *
 */

/**
 *    via_intr_channel - handle an interrupt for a single channel
 *      @card: unused
 *    @chan: handle interrupt for this channel
 *
 *    This is the "meat" of the interrupt handler,
 *    containing the actions taken each time an interrupt
 *    occurs.  All communication and coordination with
 *    userspace takes place here.
 *
 *    Locking: inside card->lock
 */

static void via_intr_channel (struct via_info *card, struct via_channel *chan)
{
      u8 status;
      int n;
      
      /* check pertinent bits of status register for action bits */
      status = inb (chan->iobase) & (VIA_SGD_FLAG | VIA_SGD_EOL | VIA_SGD_STOPPED);
      if (!status)
            return;

      /* acknowledge any flagged bits ASAP */
      outb (status, chan->iobase);

      if (!chan->sgtable) /* XXX: temporary solution */
            return;

      /* grab current h/w ptr value */
      n = atomic_read (&chan->hw_ptr);

      /* sanity check: make sure our h/w ptr doesn't have a weird value */
      assert (n >= 0);
      assert (n < chan->frag_number);

      
      /* reset SGD data structure in memory to reflect a full buffer,
       * and advance the h/w ptr, wrapping around to zero if needed
       */
      if (n == (chan->frag_number - 1)) {
            chan->sgtable[n].count = cpu_to_le32(chan->frag_size | VIA_EOL);
            atomic_set (&chan->hw_ptr, 0);
      } else {
            chan->sgtable[n].count = cpu_to_le32(chan->frag_size | VIA_FLAG);
            atomic_inc (&chan->hw_ptr);
      }

      /* accounting crap for SNDCTL_DSP_GETxPTR */
      chan->n_irqs++;
      chan->bytes += chan->frag_size;
      /* FIXME - signed overflow is undefined */
      if (chan->bytes < 0) /* handle overflow of 31-bit value */
            chan->bytes = chan->frag_size;
      /* all following checks only occur when not in mmap(2) mode */
      if (!chan->is_mapped)
      {
            /* If we are recording, then n_frags represents the number
             * of fragments waiting to be handled by userspace.
             * If we are playback, then n_frags represents the number
             * of fragments remaining to be filled by userspace.
             * We increment here.  If we reach max number of fragments,
             * this indicates an underrun/overrun.  For this case under OSS,
             * we stop the record/playback process.
             */
            if (atomic_read (&chan->n_frags) < chan->frag_number)
                  atomic_inc (&chan->n_frags);
            assert (atomic_read (&chan->n_frags) <= chan->frag_number);
            if (atomic_read (&chan->n_frags) == chan->frag_number) {
                  chan->is_active = 0;
                  via_chan_stop (chan->iobase);
            }
      }
      /* wake up anyone listening to see when interrupts occur */
      wake_up_all (&chan->wait);

      DPRINTK ("%s intr, status=0x%02X, hwptr=0x%lX, chan->hw_ptr=%d\n",
             chan->name, status, (long) inl (chan->iobase + 0x04),
             atomic_read (&chan->hw_ptr));

      DPRINTK ("%s intr, channel n_frags == %d, missed %d\n", chan->name,
             atomic_read (&chan->n_frags), missed);
}


static irqreturn_t  via_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
      struct via_info *card = dev_id;
      u32 status32;

      /* to minimize interrupt sharing costs, we use the SGD status
       * shadow register to check the status of all inputs and
       * outputs with a single 32-bit bus read.  If no interrupt
       * conditions are flagged, we exit immediately
       */
      status32 = inl (card->baseaddr + VIA_BASE0_SGD_STATUS_SHADOW);
      if (!(status32 & VIA_INTR_MASK))
        {
#ifdef CONFIG_MIDI_VIA82CXXX
             if (card->midi_devc)
                        uart401intr(irq, card->midi_devc, regs);
#endif
            return IRQ_HANDLED;
      }
      DPRINTK ("intr, status32 == 0x%08X\n", status32);

      /* synchronize interrupt handling under SMP.  this spinlock
       * goes away completely on UP
       */
      spin_lock (&card->lock);

      if (status32 & VIA_INTR_OUT)
            via_intr_channel (card, &card->ch_out);
      if (status32 & VIA_INTR_IN)
            via_intr_channel (card, &card->ch_in);
      if (status32 & VIA_INTR_FM)
            via_intr_channel (card, &card->ch_fm);

      spin_unlock (&card->lock);
      
      return IRQ_HANDLED;
}

static irqreturn_t via_new_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
      struct via_info *card = dev_id;
      u32 status32;

      /* to minimize interrupt sharing costs, we use the SGD status
       * shadow register to check the status of all inputs and
       * outputs with a single 32-bit bus read.  If no interrupt
       * conditions are flagged, we exit immediately
       */
      status32 = inl (card->baseaddr + VIA_BASE0_SGD_STATUS_SHADOW);
      if (!(status32 & VIA_NEW_INTR_MASK))
            return IRQ_NONE;
      /*
       * goes away completely on UP
       */
      spin_lock (&card->lock);

      via_intr_channel (card, &card->ch_out);
      via_intr_channel (card, &card->ch_in);
      via_intr_channel (card, &card->ch_fm);

      spin_unlock (&card->lock);
      return IRQ_HANDLED;
}


/**
 *    via_interrupt_init - Initialize interrupt handling
 *    @card: Private info for specified board
 *
 *    Obtain and reserve IRQ for using in handling audio events.
 *    Also, disable any IRQ-generating resources, to make sure
 *    we don't get interrupts before we want them.
 */

static int via_interrupt_init (struct via_info *card)
{
      u8 tmp8;

      DPRINTK ("ENTER\n");

      assert (card != NULL);
      assert (card->pdev != NULL);

      /* check for sane IRQ number. can this ever happen? */
      if (card->pdev->irq < 2) {
            printk (KERN_ERR PFX "insane IRQ %d, aborting\n",
                  card->pdev->irq);
            DPRINTK ("EXIT, returning -EIO\n");
            return -EIO;
      }

      /* VIA requires this is done */
      pci_write_config_byte(card->pdev, PCI_INTERRUPT_LINE, card->pdev->irq);
      
      if(card->legacy)
      {
            /* make sure FM irq is not routed to us */
            pci_read_config_byte (card->pdev, VIA_FM_NMI_CTRL, &tmp8);
            if ((tmp8 & VIA_CR48_FM_TRAP_TO_NMI) == 0) {
                  tmp8 |= VIA_CR48_FM_TRAP_TO_NMI;
                  pci_write_config_byte (card->pdev, VIA_FM_NMI_CTRL, tmp8);
            }
            if (request_irq (card->pdev->irq, via_interrupt, IRQF_SHARED, VIA_MODULE_NAME, card)) {
                  printk (KERN_ERR PFX "unable to obtain IRQ %d, aborting\n",
                        card->pdev->irq);
                  DPRINTK ("EXIT, returning -EBUSY\n");
                  return -EBUSY;
            }
      }
      else 
      {
            if (request_irq (card->pdev->irq, via_new_interrupt, IRQF_SHARED, VIA_MODULE_NAME, card)) {
                  printk (KERN_ERR PFX "unable to obtain IRQ %d, aborting\n",
                        card->pdev->irq);
                  DPRINTK ("EXIT, returning -EBUSY\n");
                  return -EBUSY;
            }
      }

      DPRINTK ("EXIT, returning 0\n");
      return 0;
}


/****************************************************************
 *
 * OSS DSP device
 *
 */

static struct file_operations via_dsp_fops = {
      .owner            = THIS_MODULE,
      .open       = via_dsp_open,
      .release    = via_dsp_release,
      .read       = via_dsp_read,
      .write            = via_dsp_write,
      .poll       = via_dsp_poll,
      .llseek           = no_llseek,
      .ioctl            = via_dsp_ioctl,
      .mmap       = via_dsp_mmap,
};


static int __devinit via_dsp_init (struct via_info *card)
{
      u8 tmp8;

      DPRINTK ("ENTER\n");

      assert (card != NULL);

      if(card->legacy)
      {
            /* turn off legacy features, if not already */
            pci_read_config_byte (card->pdev, VIA_FUNC_ENABLE, &tmp8);
            if (tmp8 & (VIA_CR42_SB_ENABLE |  VIA_CR42_FM_ENABLE)) {
                  tmp8 &= ~(VIA_CR42_SB_ENABLE | VIA_CR42_FM_ENABLE);
                  pci_write_config_byte (card->pdev, VIA_FUNC_ENABLE, tmp8);
            }
      }

      via_stop_everything (card);

      card->dev_dsp = register_sound_dsp (&via_dsp_fops, -1);
      if (card->dev_dsp < 0) {
            DPRINTK ("EXIT, returning -ENODEV\n");
            return -ENODEV;
      }
      DPRINTK ("EXIT, returning 0\n");
      return 0;
}


static void via_dsp_cleanup (struct via_info *card)
{
      DPRINTK ("ENTER\n");

      assert (card != NULL);
      assert (card->dev_dsp >= 0);

      via_stop_everything (card);

      unregister_sound_dsp (card->dev_dsp);

      DPRINTK ("EXIT\n");
}


static struct page * via_mm_nopage (struct vm_area_struct * vma,
                            unsigned long address, int *type)
{
      struct via_info *card = vma->vm_private_data;
      struct via_channel *chan = &card->ch_out;
      struct page *dmapage;
      unsigned long pgoff;
      int rd, wr;

      DPRINTK ("ENTER, start %lXh, ofs %lXh, pgoff %ld, addr %lXh\n",
             vma->vm_start,
             address - vma->vm_start,
             (address - vma->vm_start) >> PAGE_SHIFT,
             address);

        if (address > vma->vm_end) {
            DPRINTK ("EXIT, returning NOPAGE_SIGBUS\n");
            return NOPAGE_SIGBUS; /* Disallow mremap */
      }
        if (!card) {
            DPRINTK ("EXIT, returning NOPAGE_OOM\n");
            return NOPAGE_OOM;      /* Nothing allocated */
      }

      pgoff = vma->vm_pgoff + ((address - vma->vm_start) >> PAGE_SHIFT);
      rd = card->ch_in.is_mapped;
      wr = card->ch_out.is_mapped;

#ifndef VIA_NDEBUG
      {
      unsigned long max_bufs = chan->frag_number;
      if (rd && wr) max_bufs *= 2;
      /* via_dsp_mmap() should ensure this */
      assert (pgoff < max_bufs);
      }
#endif

      /* if full-duplex (read+write) and we have two sets of bufs,
       * then the playback buffers come first, sez soundcard.c */
      if (pgoff >= chan->page_number) {
            pgoff -= chan->page_number;
            chan = &card->ch_in;
      } else if (!wr)
            chan = &card->ch_in;

      assert ((((unsigned long)chan->pgtbl[pgoff].cpuaddr) % PAGE_SIZE) == 0);

      dmapage = virt_to_page (chan->pgtbl[pgoff].cpuaddr);
      DPRINTK ("EXIT, returning page %p for cpuaddr %lXh\n",
             dmapage, (unsigned long) chan->pgtbl[pgoff].cpuaddr);
      get_page (dmapage);
      if (type)
            *type = VM_FAULT_MINOR;
      return dmapage;
}


#ifndef VM_RESERVED
static int via_mm_swapout (struct page *page, struct file *filp)
{
      return 0;
}
#endif /* VM_RESERVED */


static struct vm_operations_struct via_mm_ops = {
      .nopage           = via_mm_nopage,

#ifndef VM_RESERVED
      .swapout    = via_mm_swapout,
#endif
};


static int via_dsp_mmap(struct file *file, struct vm_area_struct *vma)
{
      struct via_info *card;
      int nonblock = (file->f_flags & O_NONBLOCK);
      int rc = -EINVAL, rd=0, wr=0;
      unsigned long max_size, size, start, offset;

      assert (file != NULL);
      assert (vma != NULL);
      card = file->private_data;
      assert (card != NULL);

      DPRINTK ("ENTER, start %lXh, size %ld, pgoff %ld\n",
             vma->vm_start,
             vma->vm_end - vma->vm_start,
             vma->vm_pgoff);

      max_size = 0;
      if (vma->vm_flags & VM_READ) {
            rd = 1;
            via_chan_set_buffering(card, &card->ch_in, -1);
            via_chan_buffer_init (card, &card->ch_in);
            max_size += card->ch_in.page_number << PAGE_SHIFT;
      }
      if (vma->vm_flags & VM_WRITE) {
            wr = 1;
            via_chan_set_buffering(card, &card->ch_out, -1);
            via_chan_buffer_init (card, &card->ch_out);
            max_size += card->ch_out.page_number << PAGE_SHIFT;
      }

      start = vma->vm_start;
      offset = (vma->vm_pgoff << PAGE_SHIFT);
      size = vma->vm_end - vma->vm_start;

      /* some basic size/offset sanity checks */
      if (size > max_size)
            goto out;
      if (offset > max_size - size)
            goto out;

      rc = via_syscall_down (card, nonblock);
      if (rc) goto out;

      vma->vm_ops = &via_mm_ops;
      vma->vm_private_data = card;

#ifdef VM_RESERVED
      vma->vm_flags |= VM_RESERVED;
#endif

      if (rd)
            card->ch_in.is_mapped = 1;
      if (wr)
            card->ch_out.is_mapped = 1;

      mutex_unlock(&card->syscall_mutex);
      rc = 0;

out:
      DPRINTK ("EXIT, returning %d\n", rc);
      return rc;
}


static ssize_t via_dsp_do_read (struct via_info *card,
                        char __user *userbuf, size_t count,
                        int nonblock)
{
        DECLARE_WAITQUEUE(wait, current);
      const char __user *orig_userbuf = userbuf;
      struct via_channel *chan = &card->ch_in;
      size_t size;
      int n, tmp;
      ssize_t ret = 0;

      /* if SGD has not yet been started, start it */
      via_chan_maybe_start (chan);

handle_one_block:
      /* just to be a nice neighbor */
      /* Thomas Sailer:
       * But also to ourselves, release semaphore if we do so */
      if (need_resched()) {
            mutex_unlock(&card->syscall_mutex);
            schedule ();
            ret = via_syscall_down (card, nonblock);
            if (ret)
                  goto out;
      }

      /* grab current channel software pointer.  In the case of
       * recording, this is pointing to the next buffer that
       * will receive data from the audio hardware.
       */
      n = chan->sw_ptr;

      /* n_frags represents the number of fragments waiting
       * to be copied to userland.  sleep until at least
       * one buffer has been read from the audio hardware.
       */
      add_wait_queue(&chan->wait, &wait);
      for (;;) {
            __set_current_state(TASK_INTERRUPTIBLE);
            tmp = atomic_read (&chan->n_frags);
            assert (tmp >= 0);
            assert (tmp <= chan->frag_number);
            if (tmp)
                  break;
            if (nonblock || !chan->is_active) {
                  ret = -EAGAIN;
                  break;
            }

            mutex_unlock(&card->syscall_mutex);

            DPRINTK ("Sleeping on block %d\n", n);
            schedule();

            ret = via_syscall_down (card, nonblock);
            if (ret)
                  break;

            if (signal_pending (current)) {
                  ret = -ERESTARTSYS;
                  break;
            }
      }
      set_current_state(TASK_RUNNING);
      remove_wait_queue(&chan->wait, &wait);
      if (ret)
            goto out;

      /* Now that we have a buffer we can read from, send
       * as much as sample data possible to userspace.
       */
      while ((count > 0) && (chan->slop_len < chan->frag_size)) {
            size_t slop_left = chan->frag_size - chan->slop_len;
            void *base = chan->pgtbl[n / (PAGE_SIZE / chan->frag_size)].cpuaddr;
            unsigned ofs = (n % (PAGE_SIZE / chan->frag_size)) * chan->frag_size;

            size = (count < slop_left) ? count : slop_left;
            if (copy_to_user (userbuf,
                          base + ofs + chan->slop_len,
                          size)) {
                  ret = -EFAULT;
                  goto out;
            }

            count -= size;
            chan->slop_len += size;
            userbuf += size;
      }

      /* If we didn't copy the buffer completely to userspace,
       * stop now.
       */
      if (chan->slop_len < chan->frag_size)
            goto out;

      /*
       * If we get to this point, we copied one buffer completely
       * to userspace, give the buffer back to the hardware.
       */

      /* advance channel software pointer to point to
       * the next buffer from which we will copy
       */
      if (chan->sw_ptr == (chan->frag_number - 1))
            chan->sw_ptr = 0;
      else
            chan->sw_ptr++;

      /* mark one less buffer waiting to be processed */
      assert (atomic_read (&chan->n_frags) > 0);
      atomic_dec (&chan->n_frags);

      /* we are at a block boundary, there is no fragment data */
      chan->slop_len = 0;

      DPRINTK ("Flushed block %u, sw_ptr now %u, n_frags now %d\n",
            n, chan->sw_ptr, atomic_read (&chan->n_frags));

      DPRINTK ("regs==%02X %02X %02X %08X %08X %08X %08X\n",
             inb (card->baseaddr + 0x00),
             inb (card->baseaddr + 0x01),
             inb (card->baseaddr + 0x02),
             inl (card->baseaddr + 0x04),
             inl (card->baseaddr + 0x0C),
             inl (card->baseaddr + 0x80),
             inl (card->baseaddr + 0x84));

      if (count > 0)
            goto handle_one_block;

out:
      return (userbuf != orig_userbuf) ? (userbuf - orig_userbuf) : ret;
}


static ssize_t via_dsp_read(struct file *file, char __user *buffer, size_t count, loff_t *ppos)
{
      struct via_info *card;
      int nonblock = (file->f_flags & O_NONBLOCK);
      int rc;

      DPRINTK ("ENTER, file=%p, buffer=%p, count=%u, ppos=%lu\n",
             file, buffer, count, ppos ? ((unsigned long)*ppos) : 0);

      assert (file != NULL);
      card = file->private_data;
      assert (card != NULL);

      rc = via_syscall_down (card, nonblock);
      if (rc) goto out;

      if (card->ch_in.is_mapped) {
            rc = -ENXIO;
            goto out_up;
      }

      via_chan_set_buffering(card, &card->ch_in, -1);
        rc = via_chan_buffer_init (card, &card->ch_in);

      if (rc)
            goto out_up;

      rc = via_dsp_do_read (card, buffer, count, nonblock);

out_up:
      mutex_unlock(&card->syscall_mutex);
out:
      DPRINTK ("EXIT, returning %ld\n",(long) rc);
      return rc;
}


static ssize_t via_dsp_do_write (struct via_info *card,
                         const char __user *userbuf, size_t count,
                         int nonblock)
{
        DECLARE_WAITQUEUE(wait, current);
      const char __user *orig_userbuf = userbuf;
      struct via_channel *chan = &card->ch_out;
      volatile struct via_sgd_table *sgtable = chan->sgtable;
      size_t size;
      int n, tmp;
      ssize_t ret = 0;

handle_one_block:
      /* just to be a nice neighbor */
      /* Thomas Sailer:
       * But also to ourselves, release semaphore if we do so */
      if (need_resched()) {
            mutex_unlock(&card->syscall_mutex);
            schedule ();
            ret = via_syscall_down (card, nonblock);
            if (ret)
                  goto out;
      }

      /* grab current channel fragment pointer.  In the case of
       * playback, this is pointing to the next fragment that
       * should receive data from userland.
       */
      n = chan->sw_ptr;

      /* n_frags represents the number of fragments remaining
       * to be filled by userspace.  Sleep until
       * at least one fragment is available for our use.
       */
      add_wait_queue(&chan->wait, &wait);
      for (;;) {
            __set_current_state(TASK_INTERRUPTIBLE);
            tmp = atomic_read (&chan->n_frags);
            assert (tmp >= 0);
            assert (tmp <= chan->frag_number);
            if (tmp)
                  break;
            if (nonblock || !chan->is_active) {
                  ret = -EAGAIN;
                  break;
            }

            mutex_unlock(&card->syscall_mutex);

            DPRINTK ("Sleeping on page %d, tmp==%d, ir==%d\n", n, tmp, chan->is_record);
            schedule();

            ret = via_syscall_down (card, nonblock);
            if (ret)
                  break;

            if (signal_pending (current)) {
                  ret = -ERESTARTSYS;
                  break;
            }
      }
      set_current_state(TASK_RUNNING);
      remove_wait_queue(&chan->wait, &wait);
      if (ret)
            goto out;

      /* Now that we have at least one fragment we can write to, fill the buffer
       * as much as possible with data from userspace.
       */
      while ((count > 0) && (chan->slop_len < chan->frag_size)) {
            size_t slop_left = chan->frag_size - chan->slop_len;

            size = (count < slop_left) ? count : slop_left;
            if (copy_from_user (chan->pgtbl[n / (PAGE_SIZE / chan->frag_size)].cpuaddr + (n % (PAGE_SIZE / chan->frag_size)) * chan->frag_size + chan->slop_len,
                            userbuf, size)) {
                  ret = -EFAULT;
                  goto out;
            }

            count -= size;
            chan->slop_len += size;
            userbuf += size;
      }

      /* If we didn't fill up the buffer with data, stop now.
         * Put a 'stop' marker in the DMA table too, to tell the
         * audio hardware to stop if it gets here.
         */
      if (chan->slop_len < chan->frag_size) {
            sgtable[n].count = cpu_to_le32 (chan->slop_len | VIA_EOL | VIA_STOP);
            goto out;
      }

      /*
         * If we get to this point, we have filled a buffer with
         * audio data, flush the buffer to audio hardware.
         */

      /* Record the true size for the audio hardware to notice */
        if (n == (chan->frag_number - 1))
                sgtable[n].count = cpu_to_le32 (chan->frag_size | VIA_EOL);
        else
                sgtable[n].count = cpu_to_le32 (chan->frag_size | VIA_FLAG);

      /* advance channel software pointer to point to
       * the next buffer we will fill with data
       */
      if (chan->sw_ptr == (chan->frag_number - 1))
            chan->sw_ptr = 0;
      else
            chan->sw_ptr++;

      /* mark one less buffer as being available for userspace consumption */
      assert (atomic_read (&chan->n_frags) > 0);
      atomic_dec (&chan->n_frags);

      /* we are at a block boundary, there is no fragment data */
      chan->slop_len = 0;

      /* if SGD has not yet been started, start it */
      via_chan_maybe_start (chan);

      DPRINTK ("Flushed block %u, sw_ptr now %u, n_frags now %d\n",
            n, chan->sw_ptr, atomic_read (&chan->n_frags));

      DPRINTK ("regs==S=%02X C=%02X TP=%02X BP=%08X RT=%08X SG=%08X CC=%08X SS=%08X\n",
             inb (card->baseaddr + 0x00),
             inb (card->baseaddr + 0x01),
             inb (card->baseaddr + 0x02),
             inl (card->baseaddr + 0x04),
             inl (card->baseaddr + 0x08),
             inl (card->baseaddr + 0x0C),
             inl (card->baseaddr + 0x80),
             inl (card->baseaddr + 0x84));

      if (count > 0)
            goto handle_one_block;

out:
      if (userbuf - orig_userbuf)
            return userbuf - orig_userbuf;
      else
            return ret;
}


static ssize_t via_dsp_write(struct file *file, const char __user *buffer, size_t count, loff_t *ppos)
{
      struct via_info *card;
      ssize_t rc;
      int nonblock = (file->f_flags & O_NONBLOCK);

      DPRINTK ("ENTER, file=%p, buffer=%p, count=%u, ppos=%lu\n",
             file, buffer, count, ppos ? ((unsigned long)*ppos) : 0);

      assert (file != NULL);
      card = file->private_data;
      assert (card != NULL);

      rc = via_syscall_down (card, nonblock);
      if (rc) goto out;

      if (card->ch_out.is_mapped) {
            rc = -ENXIO;
            goto out_up;
      }

      via_chan_set_buffering(card, &card->ch_out, -1);
      rc = via_chan_buffer_init (card, &card->ch_out);

      if (rc)
            goto out_up;

      rc = via_dsp_do_write (card, buffer, count, nonblock);

out_up:
      mutex_unlock(&card->syscall_mutex);
out:
      DPRINTK ("EXIT, returning %ld\n",(long) rc);
      return rc;
}


static unsigned int via_dsp_poll(struct file *file, struct poll_table_struct *wait)
{
      struct via_info *card;
      struct via_channel *chan;
      unsigned int mask = 0;

      DPRINTK ("ENTER\n");

      assert (file != NULL);
      card = file->private_data;
      assert (card != NULL);

      if (file->f_mode & FMODE_READ) {
            chan = &card->ch_in;
            if (sg_active (chan->iobase))
                      poll_wait(file, &chan->wait, wait);
            if (atomic_read (&chan->n_frags) > 0)
                  mask |= POLLIN | POLLRDNORM;
      }

      if (file->f_mode & FMODE_WRITE) {
            chan = &card->ch_out;
            if (sg_active (chan->iobase))
                      poll_wait(file, &chan->wait, wait);
            if (atomic_read (&chan->n_frags) > 0)
                  mask |= POLLOUT | POLLWRNORM;
      }

      DPRINTK ("EXIT, returning %u\n", mask);
      return mask;
}


/**
 *    via_dsp_drain_playback - sleep until all playback samples are flushed
 *    @card: Private info for specified board
 *    @chan: Channel to drain
 *    @nonblock: boolean, non-zero if O_NONBLOCK is set
 *
 *    Sleeps until all playback has been flushed to the audio
 *    hardware.
 *
 *    Locking: inside card->syscall_mutex
 */

static int via_dsp_drain_playback (struct via_info *card,
                           struct via_channel *chan, int nonblock)
{
        DECLARE_WAITQUEUE(wait, current);
      int ret = 0;

      DPRINTK ("ENTER, nonblock = %d\n", nonblock);

      if (chan->slop_len > 0)
            via_chan_flush_frag (chan);

      if (atomic_read (&chan->n_frags) == chan->frag_number)
            goto out;

      via_chan_maybe_start (chan);

      add_wait_queue(&chan->wait, &wait);
      for (;;) {
            DPRINTK ("FRAGS %d FRAGNUM %d\n", atomic_read(&chan->n_frags), chan->frag_number);
            __set_current_state(TASK_INTERRUPTIBLE);
            if (atomic_read (&chan->n_frags) >= chan->frag_number)
                  break;

            if (nonblock) {
                  DPRINTK ("EXIT, returning -EAGAIN\n");
                  ret = -EAGAIN;
                  break;
            }

#ifdef VIA_DEBUG
            {
            u8 r40,r41,r42,r43,r44,r48;
            pci_read_config_byte (card->pdev, 0x40, &r40);
            pci_read_config_byte (card->pdev, 0x41, &r41);
            pci_read_config_byte (card->pdev, 0x42, &r42);
            pci_read_config_byte (card->pdev, 0x43, &r43);
            pci_read_config_byte (card->pdev, 0x44, &r44);
            pci_read_config_byte (card->pdev, 0x48, &r48);
            DPRINTK ("PCI config: %02X %02X %02X %02X %02X %02X\n",
                  r40,r41,r42,r43,r44,r48);

            DPRINTK ("regs==%02X %02X %02X %08X %08X %08X %08X\n",
                   inb (card->baseaddr + 0x00),
                   inb (card->baseaddr + 0x01),
                   inb (card->baseaddr + 0x02),
                   inl (card->baseaddr + 0x04),
                   inl (card->baseaddr + 0x0C),
                   inl (card->baseaddr + 0x80),
                   inl (card->baseaddr + 0x84));
            }

            if (!chan->is_active)
                  printk (KERN_ERR "sleeping but not active\n");
#endif

            mutex_unlock(&card->syscall_mutex);

            DPRINTK ("sleeping, nbufs=%d\n", atomic_read (&chan->n_frags));
            schedule();

            if ((ret = via_syscall_down (card, nonblock)))
                  break;

            if (signal_pending (current)) {
                  DPRINTK ("EXIT, returning -ERESTARTSYS\n");
                  ret = -ERESTARTSYS;
                  break;
            }
      }
      set_current_state(TASK_RUNNING);
      remove_wait_queue(&chan->wait, &wait);

#ifdef VIA_DEBUG
      {
            u8 r40,r41,r42,r43,r44,r48;
            pci_read_config_byte (card->pdev, 0x40, &r40);
            pci_read_config_byte (card->pdev, 0x41, &r41);
            pci_read_config_byte (card->pdev, 0x42, &r42);
            pci_read_config_byte (card->pdev, 0x43, &r43);
            pci_read_config_byte (card->pdev, 0x44, &r44);
            pci_read_config_byte (card->pdev, 0x48, &r48);
            DPRINTK ("PCI config: %02X %02X %02X %02X %02X %02X\n",
                  r40,r41,r42,r43,r44,r48);

            DPRINTK ("regs==%02X %02X %02X %08X %08X %08X %08X\n",
                   inb (card->baseaddr + 0x00),
                   inb (card->baseaddr + 0x01),
                   inb (card->baseaddr + 0x02),
                   inl (card->baseaddr + 0x04),
                   inl (card->baseaddr + 0x0C),
                   inl (card->baseaddr + 0x80),
                   inl (card->baseaddr + 0x84));

            DPRINTK ("final nbufs=%d\n", atomic_read (&chan->n_frags));
      }
#endif

out:
      DPRINTK ("EXIT, returning %d\n", ret);
      return ret;
}


/**
 *    via_dsp_ioctl_space - get information about channel buffering
 *    @card: Private info for specified board
 *    @chan: pointer to channel-specific info
 *    @arg: user buffer for returned information
 *
 *    Handles SNDCTL_DSP_GETISPACE and SNDCTL_DSP_GETOSPACE.
 *
 *    Locking: inside card->syscall_mutex
 */

static int via_dsp_ioctl_space (struct via_info *card,
                        struct via_channel *chan,
                        void __user *arg)
{
      audio_buf_info info;

      via_chan_set_buffering(card, chan, -1);

      info.fragstotal = chan->frag_number;
      info.fragsize = chan->frag_size;

      /* number of full fragments we can read/write without blocking */
      info.fragments = atomic_read (&chan->n_frags);

      if ((chan->slop_len % chan->frag_size > 0) && (info.fragments > 0))
            info.fragments--;

      /* number of bytes that can be read or written immediately
       * without blocking.
       */
      info.bytes = (info.fragments * chan->frag_size);
      if (chan->slop_len % chan->frag_size > 0)
            info.bytes += chan->frag_size - (chan->slop_len % chan->frag_size);

      DPRINTK ("EXIT, returning fragstotal=%d, fragsize=%d, fragments=%d, bytes=%d\n",
            info.fragstotal,
            info.fragsize,
            info.fragments,
            info.bytes);

      return copy_to_user (arg, &info, sizeof (info))?-EFAULT:0;
}


/**
 *    via_dsp_ioctl_ptr - get information about hardware buffer ptr
 *    @card: Private info for specified board
 *    @chan: pointer to channel-specific info
 *    @arg: user buffer for returned information
 *
 *    Handles SNDCTL_DSP_GETIPTR and SNDCTL_DSP_GETOPTR.
 *
 *    Locking: inside card->syscall_mutex
 */

static int via_dsp_ioctl_ptr (struct via_info *card,
                        struct via_channel *chan,
                        void __user *arg)
{
      count_info info;

      spin_lock_irq (&card->lock);

      info.bytes = chan->bytes;
      info.blocks = chan->n_irqs;
      chan->n_irqs = 0;

      spin_unlock_irq (&card->lock);

      if (chan->is_active) {
            unsigned long extra;
            info.ptr = atomic_read (&chan->hw_ptr) * chan->frag_size;
            extra = chan->frag_size - via_sg_offset(chan);
            info.ptr += extra;
            info.bytes += extra;
      } else {
            info.ptr = 0;
      }

      DPRINTK ("EXIT, returning bytes=%d, blocks=%d, ptr=%d\n",
            info.bytes,
            info.blocks,
            info.ptr);

      return copy_to_user (arg, &info, sizeof (info))?-EFAULT:0;
}


static int via_dsp_ioctl_trigger (struct via_channel *chan, int val)
{
      int enable, do_something;

      if (chan->is_record)
            enable = (val & PCM_ENABLE_INPUT);
      else
            enable = (val & PCM_ENABLE_OUTPUT);

      if (!chan->is_enabled && enable) {
            do_something = 1;
      } else if (chan->is_enabled && !enable) {
            do_something = -1;
      } else {
            do_something = 0;
      }

      DPRINTK ("enable=%d, do_something=%d\n",
             enable, do_something);

      if (chan->is_active && do_something)
            return -EINVAL;

      if (do_something == 1) {
            chan->is_enabled = 1;
            via_chan_maybe_start (chan);
            DPRINTK ("Triggering input\n");
      }

      else if (do_something == -1) {
            chan->is_enabled = 0;
            DPRINTK ("Setup input trigger\n");
      }

      return 0;
}


static int via_dsp_ioctl (struct inode *inode, struct file *file,
                    unsigned int cmd, unsigned long arg)
{
      int rc, rd=0, wr=0, val=0;
      struct via_info *card;
      struct via_channel *chan;
      int nonblock = (file->f_flags & O_NONBLOCK);
      int __user *ip = (int __user *)arg;
      void __user *p = (void __user *)arg;

      assert (file != NULL);
      card = file->private_data;
      assert (card != NULL);

      if (file->f_mode & FMODE_WRITE)
            wr = 1;
      if (file->f_mode & FMODE_READ)
            rd = 1;

      rc = via_syscall_down (card, nonblock);
      if (rc)
            return rc;
      rc = -EINVAL;

      switch (cmd) {

      /* OSS API version.  XXX unverified */
      case OSS_GETVERSION:
            DPRINTK ("ioctl OSS_GETVERSION, EXIT, returning SOUND_VERSION\n");
            rc = put_user (SOUND_VERSION, ip);
            break;

      /* list of supported PCM data formats */
      case SNDCTL_DSP_GETFMTS:
            DPRINTK ("DSP_GETFMTS, EXIT, returning AFMT U8|S16_LE\n");
                rc = put_user (AFMT_U8 | AFMT_S16_LE, ip);
            break;

      /* query or set current channel's PCM data format */
      case SNDCTL_DSP_SETFMT:
            if (get_user(val, ip)) {
                  rc = -EFAULT;
                  break;
            }
            DPRINTK ("DSP_SETFMT, val==%d\n", val);
            if (val != AFMT_QUERY) {
                  rc = 0;

                  if (rd)
                        rc = via_chan_set_fmt (card, &card->ch_in, val);

                  if (rc >= 0 && wr)
                        rc = via_chan_set_fmt (card, &card->ch_out, val);

                  if (rc < 0)
                        break;

                  val = rc;
            } else {
                  if ((rd && (card->ch_in.pcm_fmt & VIA_PCM_FMT_16BIT)) ||
                      (wr && (card->ch_out.pcm_fmt & VIA_PCM_FMT_16BIT)))
                        val = AFMT_S16_LE;
                  else
                        val = AFMT_U8;
            }
            DPRINTK ("SETFMT EXIT, returning %d\n", val);
                rc = put_user (val, ip);
            break;

      /* query or set number of channels (1=mono, 2=stereo, 4/6 for multichannel) */
        case SNDCTL_DSP_CHANNELS:
            if (get_user(val, ip)) {
                  rc = -EFAULT;
                  break;
            }
            DPRINTK ("DSP_CHANNELS, val==%d\n", val);
            if (val != 0) {
                  rc = 0;

                  if (rd)
                        rc = via_chan_set_stereo (card, &card->ch_in, val);

                  if (rc >= 0 && wr)
                        rc = via_chan_set_stereo (card, &card->ch_out, val);

                  if (rc < 0)
                        break;

                  val = rc;
            } else {
                  if (rd)
                        val = card->ch_in.channels;
                  else
                        val = card->ch_out.channels;
            }
            DPRINTK ("CHANNELS EXIT, returning %d\n", val);
                rc = put_user (val, ip);
            break;

      /* enable (val is not zero) or disable (val == 0) stereo */
        case SNDCTL_DSP_STEREO:
            if (get_user(val, ip)) {
                  rc = -EFAULT;
                  break;
            }
            DPRINTK ("DSP_STEREO, val==%d\n", val);
            rc = 0;

            if (rd)
                  rc = via_chan_set_stereo (card, &card->ch_in, val ? 2 : 1);
            if (rc >= 0 && wr)
                  rc = via_chan_set_stereo (card, &card->ch_out, val ? 2 : 1);

            if (rc < 0)
                  break;

            val = rc - 1;

            DPRINTK ("STEREO EXIT, returning %d\n", val);
            rc = put_user(val, ip);
            break;

      /* query or set sampling rate */
        case SNDCTL_DSP_SPEED:
            if (get_user(val, ip)) {
                  rc = -EFAULT;
                  break;
            }
            DPRINTK ("DSP_SPEED, val==%d\n", val);
            if (val < 0) {
                  rc = -EINVAL;
                  break;
            }
            if (val > 0) {
                  rc = 0;

                  if (rd)
                        rc = via_chan_set_speed (card, &card->ch_in, val);
                  if (rc >= 0 && wr)
                        rc = via_chan_set_speed (card, &card->ch_out, val);

                  if (rc < 0)
                        break;

                  val = rc;
            } else {
                  if (rd)
                        val = card->ch_in.rate;
                  else if (wr)
                        val = card->ch_out.rate;
                  else
                        val = 0;
            }
            DPRINTK ("SPEED EXIT, returning %d\n", val);
                rc = put_user (val, ip);
            break;

      /* wait until all buffers have been played, and then stop device */
      case SNDCTL_DSP_SYNC:
            DPRINTK ("DSP_SYNC\n");
            rc = 0;
            if (wr) {
                  DPRINTK ("SYNC EXIT (after calling via_dsp_drain_playback)\n");
                  rc = via_dsp_drain_playback (card, &card->ch_out, nonblock);
            }
            break;

      /* stop recording/playback immediately */
        case SNDCTL_DSP_RESET:
            DPRINTK ("DSP_RESET\n");
            if (rd) {
                  via_chan_clear (card, &card->ch_in);
                  card->ch_in.frag_number = 0;
                  card->ch_in.frag_size = 0;
                  atomic_set(&card->ch_in.n_frags, 0);
            }

            if (wr) {
                  via_chan_clear (card, &card->ch_out);
                  card->ch_out.frag_number = 0;
                  card->ch_out.frag_size = 0;
                  atomic_set(&card->ch_out.n_frags, 0);
            }

            rc = 0;
            break;

      case SNDCTL_DSP_NONBLOCK:
            file->f_flags |= O_NONBLOCK;
            rc = 0;
            break;

      /* obtain bitmask of device capabilities, such as mmap, full duplex, etc. */
      case SNDCTL_DSP_GETCAPS:
            DPRINTK ("DSP_GETCAPS\n");
            rc = put_user(VIA_DSP_CAP, ip);
            break;

      /* obtain buffer fragment size */
      case SNDCTL_DSP_GETBLKSIZE:
            DPRINTK ("DSP_GETBLKSIZE\n");

            if (rd) {
                  via_chan_set_buffering(card, &card->ch_in, -1);
                  rc = put_user(card->ch_in.frag_size, ip);
            } else if (wr) {
                  via_chan_set_buffering(card, &card->ch_out, -1);
                  rc = put_user(card->ch_out.frag_size, ip);
            }
            break;

      /* obtain information about input buffering */
      case SNDCTL_DSP_GETISPACE:
            DPRINTK ("DSP_GETISPACE\n");
            if (rd)
                  rc = via_dsp_ioctl_space (card, &card->ch_in, p);
            break;

      /* obtain information about output buffering */
      case SNDCTL_DSP_GETOSPACE:
            DPRINTK ("DSP_GETOSPACE\n");
            if (wr)
                  rc = via_dsp_ioctl_space (card, &card->ch_out, p);
            break;

      /* obtain information about input hardware pointer */
      case SNDCTL_DSP_GETIPTR:
            DPRINTK ("DSP_GETIPTR\n");
            if (rd)
                  rc = via_dsp_ioctl_ptr (card, &card->ch_in, p);
            break;

      /* obtain information about output hardware pointer */
      case SNDCTL_DSP_GETOPTR:
            DPRINTK ("DSP_GETOPTR\n");
            if (wr)
                  rc = via_dsp_ioctl_ptr (card, &card->ch_out, p);
            break;

      /* return number of bytes remaining to be played by DMA engine */
      case SNDCTL_DSP_GETODELAY:
            {
            DPRINTK ("DSP_GETODELAY\n");

            chan = &card->ch_out;

            if (!wr)
                  break;

            if (chan->is_active) {

                  val = chan->frag_number - atomic_read (&chan->n_frags);

                  assert(val >= 0);
                        
                  if (val > 0) {
                        val *= chan->frag_size;
                        val -= chan->frag_size - via_sg_offset(chan);
                  }
                  val += chan->slop_len % chan->frag_size;
            } else
                  val = 0;

            assert (val <= (chan->frag_size * chan->frag_number));

            DPRINTK ("GETODELAY EXIT, val = %d bytes\n", val);
                rc = put_user (val, ip);
            break;
            }

      /* handle the quick-start of a channel,
       * or the notification that a quick-start will
       * occur in the future
       */
      case SNDCTL_DSP_SETTRIGGER:
            if (get_user(val, ip)) {
                  rc = -EFAULT;
                  break;
            }
            DPRINTK ("DSP_SETTRIGGER, rd=%d, wr=%d, act=%d/%d, en=%d/%d\n",
                  rd, wr, card->ch_in.is_active, card->ch_out.is_active,
                  card->ch_in.is_enabled, card->ch_out.is_enabled);

            rc = 0;

            if (rd)
                  rc = via_dsp_ioctl_trigger (&card->ch_in, val);

            if (!rc && wr)
                  rc = via_dsp_ioctl_trigger (&card->ch_out, val);

            break;

      case SNDCTL_DSP_GETTRIGGER:
            val = 0;
            if ((file->f_mode & FMODE_READ) && card->ch_in.is_enabled)
                  val |= PCM_ENABLE_INPUT;
            if ((file->f_mode & FMODE_WRITE) && card->ch_out.is_enabled)
                  val |= PCM_ENABLE_OUTPUT;
            rc = put_user(val, ip);
            break;

      /* Enable full duplex.  Since we do this as soon as we are opened
       * with O_RDWR, this is mainly a no-op that always returns success.
       */
      case SNDCTL_DSP_SETDUPLEX:
            DPRINTK ("DSP_SETDUPLEX\n");
            if (!rd || !wr)
                  break;
            rc = 0;
            break;

      /* set fragment size.  implemented as a successful no-op for now */
      case SNDCTL_DSP_SETFRAGMENT:
            if (get_user(val, ip)) {
                  rc = -EFAULT;
                  break;
            }
            DPRINTK ("DSP_SETFRAGMENT, val==%d\n", val);

            if (rd)
                  rc = via_chan_set_buffering(card, &card->ch_in, val);

            if (wr)
                  rc = via_chan_set_buffering(card, &card->ch_out, val);

            DPRINTK ("SNDCTL_DSP_SETFRAGMENT (fragshift==0x%04X (%d), maxfrags==0x%04X (%d))\n",
                   val & 0xFFFF,
                   val & 0xFFFF,
                   (val >> 16) & 0xFFFF,
                   (val >> 16) & 0xFFFF);

            rc = 0;
            break;

      /* inform device of an upcoming pause in input (or output). */
      case SNDCTL_DSP_POST:
            DPRINTK ("DSP_POST\n");
            if (wr) {
                  if (card->ch_out.slop_len > 0)
                        via_chan_flush_frag (&card->ch_out);
                  via_chan_maybe_start (&card->ch_out);
            }

            rc = 0;
            break;

      /* not implemented */
      default:
            DPRINTK ("unhandled ioctl, cmd==%u, arg==%p\n",
                   cmd, p);
            break;
      }

      mutex_unlock(&card->syscall_mutex);
      DPRINTK ("EXIT, returning %d\n", rc);
      return rc;
}


static int via_dsp_open (struct inode *inode, struct file *file)
{
      int minor = iminor(inode);
      struct via_info *card;
      struct pci_dev *pdev = NULL;
      struct via_channel *chan;
      struct pci_driver *drvr;
      int nonblock = (file->f_flags & O_NONBLOCK);

      DPRINTK ("ENTER, minor=%d, file->f_mode=0x%x\n", minor, file->f_mode);

      if (!(file->f_mode & (FMODE_READ | FMODE_WRITE))) {
            DPRINTK ("EXIT, returning -EINVAL\n");
            return -EINVAL;
      }

      card = NULL;
      while ((pdev = pci_find_device(PCI_ANY_ID, PCI_ANY_ID, pdev)) != NULL) {
            drvr = pci_dev_driver (pdev);
            if (drvr == &via_driver) {
                  assert (pci_get_drvdata (pdev) != NULL);

                  card = pci_get_drvdata (pdev);
                  DPRINTK ("dev_dsp = %d, minor = %d, assn = %d\n",
                         card->dev_dsp, minor,
                         (card->dev_dsp ^ minor) & ~0xf);

                  if (((card->dev_dsp ^ minor) & ~0xf) == 0)
                        goto match;
            }
      }

      DPRINTK ("no matching %s found\n", card ? "minor" : "driver");
      return -ENODEV;

match:
      if (nonblock) {
            if (!mutex_trylock(&card->open_mutex)) {
                  DPRINTK ("EXIT, returning -EAGAIN\n");
                  return -EAGAIN;
            }
      } else {
            if (mutex_lock_interruptible(&card->open_mutex)) {
                  DPRINTK ("EXIT, returning -ERESTARTSYS\n");
                  return -ERESTARTSYS;
            }
      }

      file->private_data = card;
      DPRINTK ("file->f_mode == 0x%x\n", file->f_mode);

      /* handle input from analog source */
      if (file->f_mode & FMODE_READ) {
            chan = &card->ch_in;

            via_chan_init (card, chan);

            /* why is this forced to 16-bit stereo in all drivers? */
            chan->pcm_fmt = VIA_PCM_FMT_16BIT | VIA_PCM_FMT_STEREO;
            chan->channels = 2;

            // TO DO - use FIFO: via_capture_fifo(card, 1);
            via_chan_pcm_fmt (chan, 0);
            via_set_rate (card->ac97, chan, 44100);
      }

      /* handle output to analog source */
      if (file->f_mode & FMODE_WRITE) {
            chan = &card->ch_out;

            via_chan_init (card, chan);

            if (file->f_mode & FMODE_READ) {
                  /* if in duplex mode make the recording and playback channels
                     have the same settings */
                  chan->pcm_fmt = VIA_PCM_FMT_16BIT | VIA_PCM_FMT_STEREO;
                  chan->channels = 2;
                  via_chan_pcm_fmt (chan, 0);
                        via_set_rate (card->ac97, chan, 44100);
            } else {
                   if ((minor & 0xf) == SND_DEV_DSP16) {
                        chan->pcm_fmt = VIA_PCM_FMT_16BIT;
                        via_chan_pcm_fmt (chan, 0);
                        via_set_rate (card->ac97, chan, 44100);
                  } else {
                        via_chan_pcm_fmt (chan, 1);
                        via_set_rate (card->ac97, chan, 8000);
                  }
            }
      }

      DPRINTK ("EXIT, returning 0\n");
      return nonseekable_open(inode, file);
}


static int via_dsp_release(struct inode *inode, struct file *file)
{
      struct via_info *card;
      int nonblock = (file->f_flags & O_NONBLOCK);
      int rc;

      DPRINTK ("ENTER\n");

      assert (file != NULL);
      card = file->private_data;
      assert (card != NULL);

      rc = via_syscall_down (card, nonblock);
      if (rc) {
            DPRINTK ("EXIT (syscall_down error), rc=%d\n", rc);
            return rc;
      }

      if (file->f_mode & FMODE_WRITE) {
            rc = via_dsp_drain_playback (card, &card->ch_out, nonblock);
            if (rc && rc != -ERESTARTSYS) /* Nobody needs to know about ^C */
                  printk (KERN_DEBUG "via_audio: ignoring drain playback error %d\n", rc);

            via_chan_free (card, &card->ch_out);
            via_chan_buffer_free(card, &card->ch_out);
      }

      if (file->f_mode & FMODE_READ) {
            via_chan_free (card, &card->ch_in);
            via_chan_buffer_free (card, &card->ch_in);
      }

      mutex_unlock(&card->syscall_mutex);
      mutex_unlock(&card->open_mutex);

      DPRINTK ("EXIT, returning 0\n");
      return 0;
}


/****************************************************************
 *
 * Chip setup and kernel registration
 *
 *
 */

static int __devinit via_init_one (struct pci_dev *pdev, const struct pci_device_id *id)
{
#ifdef CONFIG_MIDI_VIA82CXXX
      u8 r42;
#endif
      int rc;
      struct via_info *card;
      static int printed_version;

      DPRINTK ("ENTER\n");

      if (printed_version++ == 0)
            printk (KERN_INFO "Via 686a/8233/8235 audio driver " VIA_VERSION "\n");

      rc = pci_enable_device (pdev);
      if (rc)
            goto err_out;

      rc = pci_request_regions (pdev, "via82cxxx_audio");
      if (rc)
            goto err_out_disable;

      rc = pci_set_dma_mask(pdev, DMA_32BIT_MASK);
      if (rc)
            goto err_out_res;
      rc = pci_set_consistent_dma_mask(pdev, DMA_32BIT_MASK);
      if (rc)
            goto err_out_res;

      card = kmalloc (sizeof (*card), GFP_KERNEL);
      if (!card) {
            printk (KERN_ERR PFX "out of memory, aborting\n");
            rc = -ENOMEM;
            goto err_out_res;
      }

      pci_set_drvdata (pdev, card);

      memset (card, 0, sizeof (*card));
      card->pdev = pdev;
      card->baseaddr = pci_resource_start (pdev, 0);
      card->card_num = via_num_cards++;
      spin_lock_init (&card->lock);
      spin_lock_init (&card->ac97_lock);
      mutex_init(&card->syscall_mutex);
      mutex_init(&card->open_mutex);

      /* we must init these now, in case the intr handler needs them */
      via_chan_init_defaults (card, &card->ch_out);
      via_chan_init_defaults (card, &card->ch_in);
      via_chan_init_defaults (card, &card->ch_fm);

      /* if BAR 2 is present, chip is Rev H or later,
       * which means it has a few extra features */
      if (pci_resource_start (pdev, 2) > 0)
            card->rev_h = 1;
            
      /* Overkill for now, but more flexible done right */
      
      card->intmask = id->driver_data;
      card->legacy = !card->intmask;
      card->sixchannel = id->driver_data;
      
      if(card->sixchannel)
            printk(KERN_INFO PFX "Six channel audio available\n");
      if (pdev->irq < 1) {
            printk (KERN_ERR PFX "invalid PCI IRQ %d, aborting\n", pdev->irq);
            rc = -ENODEV;
            goto err_out_kfree;
      }

      if (!(pci_resource_flags (pdev, 0) & IORESOURCE_IO)) {
            printk (KERN_ERR PFX "unable to locate I/O resources, aborting\n");
            rc = -ENODEV;
            goto err_out_kfree;
      }

      pci_set_master(pdev);
      
      /*
       * init AC97 mixer and codec
       */
      rc = via_ac97_init (card);
      if (rc) {
            printk (KERN_ERR PFX "AC97 init failed, aborting\n");
            goto err_out_kfree;
      }

      /*
       * init DSP device
       */
      rc = via_dsp_init (card);
      if (rc) {
            printk (KERN_ERR PFX "DSP device init failed, aborting\n");
            goto err_out_have_mixer;
      }

      /*
       * init and turn on interrupts, as the last thing we do
       */
      rc = via_interrupt_init (card);
      if (rc) {
            printk (KERN_ERR PFX "interrupt init failed, aborting\n");
            goto err_out_have_dsp;
      }

      printk (KERN_INFO PFX "board #%d at 0x%04lX, IRQ %d\n",
            card->card_num + 1, card->baseaddr, pdev->irq);

#ifdef CONFIG_MIDI_VIA82CXXX
      /* Disable by default */
      card->midi_info.io_base = 0;

      if(card->legacy)
      {
            pci_read_config_byte (pdev, 0x42, &r42);
            /* Disable MIDI interrupt */
            pci_write_config_byte (pdev, 0x42, r42 | VIA_CR42_MIDI_IRQMASK);
            if (r42 & VIA_CR42_MIDI_ENABLE)
            {
                  if (r42 & VIA_CR42_MIDI_PNP) /* Address selected by iobase 2 - not tested */
                        card->midi_info.io_base = pci_resource_start (pdev, 2);
                  else /* Address selected by byte 0x43 */
                  {
                        u8 r43;
                        pci_read_config_byte (pdev, 0x43, &r43);
                        card->midi_info.io_base = 0x300 + ((r43 & 0x0c) << 2);
                  }

                  card->midi_info.irq = -pdev->irq;
                  if (probe_uart401(& card->midi_info, THIS_MODULE))
                  {
                        card->midi_devc=midi_devs[card->midi_info.slots[4]]->devc;
                        pci_write_config_byte(pdev, 0x42, r42 & ~VIA_CR42_MIDI_IRQMASK);
                        printk("Enabled Via MIDI\n");
                  }
            }
      }
#endif

      DPRINTK ("EXIT, returning 0\n");
      return 0;

err_out_have_dsp:
      via_dsp_cleanup (card);

err_out_have_mixer:
      via_ac97_cleanup (card);

err_out_kfree:
#ifndef VIA_NDEBUG
      memset (card, OSS_POISON_FREE, sizeof (*card)); /* poison memory */
#endif
      kfree (card);

err_out_res:
      pci_release_regions (pdev);

err_out_disable:
      pci_disable_device (pdev);

err_out:
      pci_set_drvdata (pdev, NULL);
      DPRINTK ("EXIT - returning %d\n", rc);
      return rc;
}


static void __devexit via_remove_one (struct pci_dev *pdev)
{
      struct via_info *card;

      DPRINTK ("ENTER\n");

      assert (pdev != NULL);
      card = pci_get_drvdata (pdev);
      assert (card != NULL);

#ifdef CONFIG_MIDI_VIA82CXXX
      if (card->midi_info.io_base)
            unload_uart401(&card->midi_info);
#endif

      free_irq (card->pdev->irq, card);
      via_dsp_cleanup (card);
      via_ac97_cleanup (card);

#ifndef VIA_NDEBUG
      memset (card, OSS_POISON_FREE, sizeof (*card)); /* poison memory */
#endif
      kfree (card);

      pci_set_drvdata (pdev, NULL);

      pci_release_regions (pdev);
      pci_disable_device (pdev);
      pci_set_power_state (pdev, 3); /* ...zzzzzz */

      DPRINTK ("EXIT\n");
      return;
}


/****************************************************************
 *
 * Driver initialization and cleanup
 *
 *
 */

static int __init init_via82cxxx_audio(void)
{
      int rc;

      DPRINTK ("ENTER\n");

      rc = pci_register_driver (&via_driver);
      if (rc) {
            DPRINTK ("EXIT, returning %d\n", rc);
            return rc;
      }

      DPRINTK ("EXIT, returning 0\n");
      return 0;
}


static void __exit cleanup_via82cxxx_audio(void)
{
      DPRINTK ("ENTER\n");

      pci_unregister_driver (&via_driver);

      DPRINTK ("EXIT\n");
}


module_init(init_via82cxxx_audio);
module_exit(cleanup_via82cxxx_audio);

MODULE_AUTHOR("Jeff Garzik");
MODULE_DESCRIPTION("DSP audio and mixer driver for Via 82Cxxx audio devices");
MODULE_LICENSE("GPL");


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