patch-2.4.0-test9 linux/drivers/sound/cs4281.c

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diff -u --recursive --new-file v2.4.0-test8/linux/drivers/sound/cs4281.c linux/drivers/sound/cs4281.c
@@ -0,0 +1,2678 @@
+//*****************************************************************************
+//
+//      "cs4281.c" --  Cirrus Logic-Crystal CS4281 linux audio driver.
+//
+//      Copyright (C) 2000  Cirrus Logic Corp.  
+//            -- adapted from drivers by Thomas Sailer, 
+//            -- but don't bug him; Problems should go to:
+//            -- gw boynton (wesb@crystal.cirrus.com) or
+//            -- tom woller (twoller@crystal.cirrus.com).
+//
+//      This program is free software; you can redistribute it and/or modify
+//      it under the terms of the GNU General Public License as published by
+//      the Free Software Foundation; either version 2 of the License, or
+//      (at your option) any later version.
+//
+//      This program is distributed in the hope that it will be useful,
+//      but WITHOUT ANY WARRANTY; without even the implied warranty of
+//      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//      GNU General Public License for more details.
+//
+//      You should have received a copy of the GNU General Public License
+//      along with this program; if not, write to the Free Software
+//      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+//
+// Module command line parameters:
+//   none
+//
+//  Supported devices:
+//  /dev/dsp    standard /dev/dsp device, (mostly) OSS compatible
+//  /dev/mixer  standard /dev/mixer device, (mostly) OSS compatible
+//  /dev/midi   simple MIDI UART interface, no ioctl
+//
+//
+//
+
+// *****************************************************************************
+
+#include <linux/module.h>
+#include <linux/string.h>
+#include <linux/ioport.h>
+#include <linux/sched.h>
+#include <linux/delay.h>
+#include <linux/sound.h>
+#include <linux/malloc.h>
+#include <linux/soundcard.h>
+#include <linux/pci.h>
+#include <linux/bitops.h>
+#include <linux/spinlock.h>
+#include <asm/io.h>
+#include <asm/dma.h>
+#include <linux/init.h>
+#include <linux/poll.h>
+#include <asm/uaccess.h>
+#include <asm/hardirq.h>
+#include <linux/vmalloc.h>
+#include "dm.h"
+#include "cs4281_hwdefs.h"
+
+EXPORT_NO_SYMBOLS;
+
+#undef OSS_DOCUMENTED_MIXER_SEMANTICS
+
+// --------------------------------------------------------------------- 
+
+#ifndef PCI_VENDOR_ID_CIRRUS
+#define PCI_VENDOR_ID_CIRRUS          0x1013
+#endif
+#ifndef PCI_DEVICE_ID_CRYSTAL_CS4281
+#define PCI_DEVICE_ID_CRYSTAL_CS4281  0x6005
+#endif
+
+#define CS4281_MAGIC  ((PCI_DEVICE_ID_CRYSTAL_CS4281<<16) | PCI_VENDOR_ID_CIRRUS)
+
+#define CSDEBUG 1
+//
+// Turn on/off debugging compilation by using 1/0 respectively for CSDEBUG
+//
+//
+// CSDEBUG is usual mode is set to 1, then use the
+// cs_debuglevel and cs_debugmask to turn on or off debugging.
+// Debug level of 1 has been defined to be kernel errors and info
+// that should be printed on any released driver.
+//
+#if CSDEBUG
+extern unsigned cs_debugmask;
+extern unsigned cs_debuglevel;
+#define CS_DBGOUT(mask,level,x) if((cs_debuglevel >= (level)) && ((mask) & cs_debugmask)) {x;} 
+#else
+#define CS_DBGOUT(mask,level,x) 
+#endif
+//
+// cs_debugmask areas
+//
+#define CS_INIT	 	0x00000001		// initialization and probe functions
+#define CS_ERROR 	0x00000002		// tmp debugging bit placeholder
+#define CS_INTERRUPT	0x00000004		// interrupt handler (separate from all other)
+#define CS_FUNCTION 	0x00000008		// enter/leave functions 
+#define CS_WAVE_WRITE 	0x00000010		// write information for wave
+#define CS_WAVE_READ 	0x00000020		// read information for wave
+#define CS_MIDI_WRITE 	0x00000040		// write information for midi
+#define CS_MIDI_READ 	0x00000080		// read information for midi
+#define CS_MPU401_WRITE 0x00000100		// write information for mpu401
+#define CS_MPU401_READ 	0x00000200		// read information for mpu401
+#define CS_OPEN		0x00000400		// all open functions in the driver
+#define CS_RELEASE	0x00000800		// all release functions in the driver
+#define CS_PARMS	0x00001000		// functional and operational parameters
+#define CS_TMP		0x10000000		// tmp debug mask bit
+
+unsigned cs_debuglevel=1;			// levels range from 1-9
+unsigned cs_debugmask=CS_INIT | CS_ERROR;	// use CS_DBGOUT with various mask values
+#if MODULE
+MODULE_PARM(cs_debuglevel, "i");
+MODULE_PARM(cs_debugmask, "i");
+#endif
+
+// MIDI buffer sizes 
+#define MIDIINBUF  500
+#define MIDIOUTBUF 500
+
+#define FMODE_MIDI_SHIFT 3
+#define FMODE_MIDI_READ  (FMODE_READ << FMODE_MIDI_SHIFT)
+#define FMODE_MIDI_WRITE (FMODE_WRITE << FMODE_MIDI_SHIFT)
+
+#define RSRCISIOREGION(dev,num) ((dev)->resource[(num)].start != 0 && \
+	 ((dev)->resource[(num)].flags & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_IO)
+#define RSRCISMEMORYREGION(dev,num) ((dev)->resource[(num)].start != 0 && \
+	 ((dev)->resource[(num)].flags & PCI_BASE_ADDRESS_SPACE) == PCI_BASE_ADDRESS_SPACE_MEMORY)
+#define RSRCADDRESS(dev,num) ((dev)->resource[(num)].start)
+
+#define CS4281_MAJOR_VERSION 	0
+#define CS4281_MINOR_VERSION 	4   
+#ifdef __ia64__
+#define CS4281_ARCH	     	64  //architecture key
+#else
+#define CS4281_ARCH	     	32  //architecture key
+#endif
+
+struct cs4281_state {
+	// magic 
+	unsigned int magic;
+
+	// we keep the cards in a linked list 
+	struct cs4281_state *next;
+
+	// pcidev is needed to turn off the DDMA controller at driver shutdown 
+	struct pci_dev *pcidev;
+
+	// soundcore stuff 
+	int dev_audio;
+	int dev_mixer;
+	int dev_midi;
+
+	// hardware resources 
+	unsigned int pBA0phys, pBA1phys;
+	char *pBA0, *pBA1; 
+	unsigned int irq;
+	int endofbuffer;
+
+	// mixer registers 
+	struct {
+		unsigned short vol[10];
+		unsigned int recsrc;
+		unsigned int modcnt;
+		unsigned short micpreamp;
+	} mix;
+
+	// wave stuff   // Note that play & record formats must be the same *wb.
+	unsigned fmt;
+	unsigned channels;
+	unsigned rate;
+	unsigned char clkdiv;
+	unsigned ena;
+
+	spinlock_t lock;
+	struct semaphore open_sem;
+	mode_t open_mode;
+	wait_queue_head_t open_wait;
+
+	struct dmabuf {
+		void *rawbuf;            // Physical address of  
+		dma_addr_t dmaaddr; 
+		unsigned buforder;       // Log base 2 of 'rawbuf' size in bytes..
+		unsigned numfrag;        // # of 'fragments' in the buffer.
+		unsigned fragshift;      // Log base 2 of fragment size.
+		unsigned hwptr, swptr;
+		unsigned total_bytes;    // # bytes process since open.
+		unsigned blocks;    	 // last returned blocks value GETOPTR
+		int count;
+		unsigned error; // over/underrun 
+		wait_queue_head_t wait;
+		// redundant, but makes calculations easier 
+		unsigned fragsize;       // 2**fragshift..
+		unsigned dmasize;        // 2**buforder.
+		unsigned fragsamples;
+		// OSS stuff 
+		unsigned mapped:1;       // Buffer mapped in cs4281_mmap()?
+		unsigned ready:1;        // prog_dmabuf_dac()/adc() successful?
+		unsigned endcleared:1;
+		unsigned ossfragshift;
+		int ossmaxfrags;
+		unsigned subdivision;
+	} dma_dac, dma_adc;
+
+	// midi stuff 
+	struct {
+		unsigned ird, iwr, icnt;
+		unsigned ord, owr, ocnt;
+		wait_queue_head_t iwait;
+		wait_queue_head_t owait;
+		struct timer_list timer;
+		unsigned char ibuf[MIDIINBUF];
+		unsigned char obuf[MIDIOUTBUF];
+	} midi;
+
+};
+
+
+struct cs4281_state *devs = NULL;
+// --------------------------------------------------------------------- 
+//
+//		Hardware Interfaces For the CS4281
+//
+
+
+//******************************************************************************
+// "delayus()-- Delay for the specified # of microseconds.
+//******************************************************************************
+static void delayus(u32 delay)
+{
+	u32 j;   
+	if(delay > 9999)
+	{
+		j = (delay * HZ)/1000000;   /* calculate delay in jiffies  */
+		if(j<1) 
+			j=1;               /* minimum one jiffy. */
+		current->state = TASK_UNINTERRUPTIBLE;  
+		schedule_timeout(j);       
+	}
+	else
+		udelay(delay);
+	return;                      
+}
+
+
+//******************************************************************************
+// "cs4281_read_ac97" -- Reads a word from the specified location in the
+//               CS4281's address space(based on the BA0 register).
+//
+// 1. Write ACCAD = Command Address Register = 46Ch for AC97 register address
+// 2. Write ACCDA = Command Data Register = 470h for data to write to AC97 register,
+//                                            0h for reads.
+// 3. Write ACCTL = Control Register = 460h for initiating the write
+// 4. Read ACCTL = 460h, DCV should be reset by now and 460h = 17h
+// 5. if DCV not cleared, break and return error
+// 6. Read ACSTS = Status Register = 464h, check VSTS bit
+//****************************************************************************
+static int cs4281_read_ac97(struct cs4281_state *card, u32 offset, u32 *value)
+{
+	u32 count, status;
+
+	// Make sure that there is not data sitting
+	// around from a previous uncompleted access.
+	// ACSDA = Status Data Register = 47Ch
+	status = readl(card->pBA0+BA0_ACSDA);
+
+	// Setup the AC97 control registers on the CS4281 to send the
+	// appropriate command to the AC97 to perform the read.
+	// ACCAD = Command Address Register = 46Ch
+	// ACCDA = Command Data Register = 470h
+	// ACCTL = Control Register = 460h
+	// bit DCV - will clear when process completed
+	// bit CRW - Read command
+	// bit VFRM - valid frame enabled
+	// bit ESYN - ASYNC generation enabled
+
+	// Get the actual AC97 register from the offset
+	writel(offset - BA0_AC97_RESET, card->pBA0+BA0_ACCAD);
+	writel(0, card->pBA0+BA0_ACCDA);
+	writel(ACCTL_DCV | ACCTL_CRW | ACCTL_VFRM | ACCTL_ESYN, card->pBA0+BA0_ACCTL);
+
+	 // Wait for the read to occur.
+	for(count = 0; count < 10; count++)
+	{
+		// First, we want to wait for a short time.
+		udelay(25);
+
+		// Now, check to see if the read has completed.
+		// ACCTL = 460h, DCV should be reset by now and 460h = 17h
+		if( !(readl(card->pBA0+BA0_ACCTL) & ACCTL_DCV))
+			break;
+	}
+
+	 // Make sure the read completed.
+	if(readl(card->pBA0+BA0_ACCTL) & ACCTL_DCV)
+ 	       return 1;
+
+	 // Wait for the valid status bit to go active.
+	for(count = 0; count < 10; count++)
+	{
+		// Read the AC97 status register.
+		// ACSTS = Status Register = 464h
+		status = readl(card->pBA0+BA0_ACSTS);
+
+		// See if we have valid status.
+		// VSTS - Valid Status
+		if(status & ACSTS_VSTS)
+			break;
+		// Wait for a short while.
+		udelay(25);
+	}
+
+	 // Make sure we got valid status.
+	if(!(status & ACSTS_VSTS))
+		return 1;
+
+	// Read the data returned from the AC97 register.
+	// ACSDA = Status Data Register = 474h
+	*value = readl(card->pBA0+BA0_ACSDA);
+
+	// Success.
+	return(0);
+}
+
+
+//****************************************************************************
+//
+// "cs4281_write_ac97()"-- writes a word to the specified location in the
+// CS461x's address space (based on the part's base address zero register).
+//
+// 1. Write ACCAD = Command Address Register = 46Ch for AC97 register address
+// 2. Write ACCDA = Command Data Register = 470h for data to write to AC97 reg.
+// 3. Write ACCTL = Control Register = 460h for initiating the write
+// 4. Read ACCTL = 460h, DCV should be reset by now and 460h = 07h
+// 5. if DCV not cleared, break and return error
+//
+//****************************************************************************
+static int cs4281_write_ac97(struct cs4281_state *card, u32 offset, u32 value)
+{
+	u32 count, status;
+
+	CS_DBGOUT(CS_FUNCTION, 2, printk(KERN_INFO "cs4281: cs_4281_write_ac97()+ \n") );
+
+	 // Setup the AC97 control registers on the CS4281 to send the
+	 // appropriate command to the AC97 to perform the read.
+	 // ACCAD = Command Address Register = 46Ch
+	 // ACCDA = Command Data Register = 470h
+	 // ACCTL = Control Register = 460h
+	 // set DCV - will clear when process completed
+	 // reset CRW - Write command
+	 // set VFRM - valid frame enabled
+	 // set ESYN - ASYNC generation enabled
+	 // set RSTN - ARST# inactive, AC97 codec not reset
+
+	 // Get the actual AC97 register from the offset
+
+	writel(offset - BA0_AC97_RESET, card->pBA0+BA0_ACCAD);
+	writel(value, card->pBA0+BA0_ACCDA);
+	writel(ACCTL_DCV | ACCTL_VFRM | ACCTL_ESYN, card->pBA0+BA0_ACCTL);
+
+	 // Wait for the write to occur.
+	for(count = 0; count < 10; count++)
+	{
+		// First, we want to wait for a short time.
+		udelay(25);
+		// Now, check to see if the write has completed.
+		// ACCTL = 460h, DCV should be reset by now and 460h = 07h
+		status = readl(card->pBA0+BA0_ACCTL);
+		if(!(status & ACCTL_DCV))
+			break;
+	}
+
+	// Make sure the write completed.
+	if(status & ACCTL_DCV)
+	{
+		CS_DBGOUT(CS_ERROR, 1, printk(KERN_INFO 
+			"cs4281: cs_4281_write_ac97()- unable to write. ACCTL_DCV active\n") );
+		return 1;
+	}
+	CS_DBGOUT(CS_FUNCTION, 2, printk(KERN_INFO "cs4281: cs_4281_write_ac97()- 0\n") );
+	// Success.
+	return 0;
+}
+
+
+//******************************************************************************
+// "Init4281()" -- Bring up the part.
+//******************************************************************************
+static int cs4281_hw_init(struct cs4281_state *card)
+{
+	u32 ac97_slotid;
+	u32 temp1, temp2;
+
+	CS_DBGOUT(CS_FUNCTION, 2, printk(KERN_INFO "cs4281: cs4281_hw_init()+ \n") );
+	//***************************************7
+	//  Set up the Sound System Configuration
+	//***************************************
+
+	 // Set the 'Configuration Write Protect' register
+	 // to 4281h.  Allows vendor-defined configuration
+	 // space between 0e4h and 0ffh to be written.
+
+	writel(0x4281, card->pBA0+BA0_CWPR);                       // (3e0h)
+
+	 // (0), Blast the clock control register to zero so that the
+	 // PLL starts out in a known state, and blast the master serial
+	 // port control register to zero so that the serial ports also
+	 // start out in a known state.
+
+	writel(0, card->pBA0+BA0_CLKCR1);                          // (400h)
+	writel(0, card->pBA0+BA0_SERMC);                           // (420h)
+
+
+	 // (1), Make ESYN go to zero to turn off
+	 // the Sync pulse on the AC97 link.
+
+	writel(0, card->pBA0+BA0_ACCTL);
+	udelay(50);
+
+
+	 // (2) Drive the ARST# pin low for a minimum of 1uS (as defined in
+	 // the AC97 spec) and then drive it high.  This is done for non
+	 // AC97 modes since there might be logic external to the CS461x
+	 // that uses the ARST# line for a reset.
+
+	writel(0, card->pBA0+BA0_SPMC);                            // (3ech)
+	udelay(100);
+	writel(SPMC_RSTN, card->pBA0+BA0_SPMC);
+	delayus(50000);     // Wait 50 ms for ABITCLK to become stable.
+
+	// (3) Turn on the Sound System Clocks.
+	writel(CLKCR1_PLLP, card->pBA0+BA0_CLKCR1);                // (400h)
+	delayus(50000);     // Wait for the PLL to stabilize.
+	// Turn on clocking of the core (CLKCR1(400h) = 0x00000030)
+	writel(CLKCR1_PLLP | CLKCR1_SWCE, card->pBA0+BA0_CLKCR1);
+
+	// (4) Power on everything for now..
+	writel(0x7E, card->pBA0 + BA0_SSPM);                       // (740h)
+
+	// (5) Wait for clock stabilization.
+	for(temp1=0; temp1<1000;  temp1++)
+	{
+		udelay(1000);
+		if(readl(card->pBA0+BA0_CLKCR1) & CLKCR1_DLLRDY)
+			break;
+	}
+	if(!(readl(card->pBA0+BA0_CLKCR1) & CLKCR1_DLLRDY))
+	{
+		CS_DBGOUT(CS_ERROR, 1, printk(KERN_ERR "cs4281: DLLRDY failed!\n") );
+		return -EIO;
+	}
+
+	// (6) Enable ASYNC generation.
+	writel(ACCTL_ESYN, card->pBA0+BA0_ACCTL);                  // (460h)
+
+	// Now wait 'for a short while' to allow the  AC97
+	// part to start generating bit clock. (so we don't
+	// Try to start the PLL without an input clock.)
+	delayus(50000);
+
+	// Set the serial port timing configuration, so that the
+	// clock control circuit gets its clock from the right place.
+	writel(SERMC_PTC_AC97, card->pBA0+BA0_SERMC);              // (420h)=2.
+
+	// (7) Wait for the codec ready signal from the AC97 codec.
+
+	for(temp1=0; temp1<1000; temp1++)
+	{
+		// Delay a mil to let things settle out and
+		// to prevent retrying the read too quickly.
+		udelay(1000);
+		if( readl(card->pBA0+BA0_ACSTS) & ACSTS_CRDY )	// If ready,  (464h)
+			break;                                  //   exit the 'for' loop.
+	}
+	if( !(readl(card->pBA0+BA0_ACSTS) & ACSTS_CRDY) )       // If never came ready,
+	{
+		CS_DBGOUT(CS_FUNCTION, 2, 
+			printk(KERN_ERR "cs4281: ACSTS never came ready!\n") );
+		return -EIO;                                //   exit initialization.
+	}
+
+	 // (8) Assert the 'valid frame' signal so we can
+	 // begin sending commands to the AC97 codec.
+	writel(ACCTL_VFRM | ACCTL_ESYN, card->pBA0+BA0_ACCTL);   // (460h)
+
+	 // (9), Wait until CODEC calibration is finished.
+	 // Print an error message if it doesn't.
+	for(temp1 = 0; temp1 < 1000; temp1++)
+	{
+		delayus(10000);
+		// Read the AC97 Powerdown Control/Status Register.
+		cs4281_read_ac97(card, BA0_AC97_POWERDOWN, &temp2);
+		if( (temp2 & 0x0000000F) == 0x0000000F )
+			break;
+	}
+	if ( (temp2 & 0x0000000F) != 0x0000000F )
+	{
+		CS_DBGOUT(CS_FUNCTION, 2, printk(KERN_ERR 
+			"cs4281: Codec failed to calibrate.  Status = %.8x.\n", temp2) );
+		return -EIO;
+	}
+
+	 // (10), Set the serial port timing configuration, so that the
+	 // clock control circuit gets its clock from the right place.
+	writel(SERMC_PTC_AC97, card->pBA0+BA0_SERMC);              // (420h)=2.
+
+
+	 // (11) Wait until we've sampled input slots 3 & 4 as valid, meaning
+	 // that the codec is pumping ADC data across the AC link.
+	for(temp1=0; temp1<1000; temp1++)
+	{
+		// Delay a mil to let things settle out and
+		// to prevent retrying the read too quickly.
+		delayus(1000);    //(test)
+
+		// Read the input slot valid register;  See
+		// if input slots 3 and 4 are valid yet.
+		if( (readl(card->pBA0+BA0_ACISV) & (ACISV_ISV3 | ACISV_ISV4) ) 
+				==  (ACISV_ISV3 | ACISV_ISV4))
+			break;    // Exit the 'for' if slots are valid.
+	}
+       	// If we never got valid data, exit initialization.
+	if( (readl(card->pBA0+BA0_ACISV) & (ACISV_ISV3 | ACISV_ISV4) ) 
+		!= (ACISV_ISV3 | ACISV_ISV4))
+	{
+		CS_DBGOUT(CS_FUNCTION, 2, printk(KERN_ERR "cs4281: Never got valid data!\n"));
+       		return -EIO;     // If no valid data, exit initialization.
+	}
+
+	// (12), Start digital data transfer of audio data to the codec.
+	writel(ACOSV_SLV3 | ACOSV_SLV4, card->pBA0+BA0_ACOSV);             // (468h)
+
+
+	//**************************************
+	// Unmute the Master and Alternate
+	// (headphone) volumes.  Set to max.
+	//**************************************
+	cs4281_write_ac97(card,BA0_AC97_HEADPHONE_VOLUME, 0);
+	cs4281_write_ac97(card,BA0_AC97_MASTER_VOLUME, 0);
+
+	//******************************************
+	// Power on the DAC(AddDACUser()from main())
+	//******************************************
+	cs4281_read_ac97(card,BA0_AC97_POWERDOWN, &temp1);
+	cs4281_write_ac97(card,BA0_AC97_POWERDOWN, temp1 &= 0xfdff);
+
+	// Wait until we sample a DAC ready state.
+	for(temp2=0; temp2<32; temp2++)
+	{
+		// Let's wait a mil to let things settle.
+		delayus(1000);
+		// Read the current state of the power control reg.
+		cs4281_read_ac97(card, BA0_AC97_POWERDOWN, &temp1);
+		// If the DAC ready state bit is set, stop waiting.
+		if(temp1 & 0x2)
+			break;
+	}
+
+	//******************************************
+	// Power on the ADC(AddADCUser()from main())
+	//******************************************
+	cs4281_read_ac97(card, BA0_AC97_POWERDOWN, &temp1);
+	cs4281_write_ac97(card, BA0_AC97_POWERDOWN, temp1 &= 0xfeff);
+
+	// Wait until we sample ADC ready state.
+	for(temp2=0; temp2<32; temp2++)
+	{
+		// Let's wait a mil to let things settle.
+		delayus(1000);
+		// Read the current state of the power control reg.
+		cs4281_read_ac97(card, BA0_AC97_POWERDOWN, &temp1);
+		// If the ADC ready state bit is set, stop waiting.
+		if(temp1 & 0x1)
+			break;
+	}
+	// Set up 4281 Register contents that
+	// don't change for boot duration.
+
+	// For playback, we map AC97 slot 3 and 4(Left
+	// & Right PCM playback) to DMA Channel 0.
+	// Set the fifo to be 15 bytes at offset zero.
+
+	ac97_slotid = 0x01000f00;	// FCR0.RS[4:0]=1(=>slot4, right PCM playback).
+					// FCR0.LS[4:0]=0(=>slot3, left PCM playback).
+				 	// FCR0.SZ[6-0]=15; FCR0.OF[6-0]=0.
+	writel(ac97_slotid, card->pBA0 + BA0_FCR0);                 // (180h)
+	writel(ac97_slotid | FCRn_FEN, card->pBA0 + BA0_FCR0);      // Turn on FIFO Enable.
+
+	// For capture, we map AC97 slot 10 and 11(Left
+	// and Right PCM Record) to DMA Channel 1.
+	// Set the fifo to be 15 bytes at offset sixteen.
+	ac97_slotid = 0x0B0A0f10;	// FCR1.RS[4:0]=11(=>slot11, right PCM record).
+	       				// FCR1.LS[4:0]=10(=>slot10, left PCM record).
+					// FCR1.SZ[6-0]=15; FCR1.OF[6-0]=16.
+	writel(ac97_slotid | FCRn_PSH, card->pBA0 + BA0_FCR1);      // (184h)
+	writel(ac97_slotid | FCRn_FEN, card->pBA0 + BA0_FCR1);      // Turn on FIFO Enable.
+
+	// Map the Playback SRC to the same AC97 slots(3 & 4--
+	// --Playback left & right)as DMA channel 0.
+	// Map the record SRC to the same AC97 slots(10 & 11--
+	// -- Record left & right) as DMA channel 1.
+
+	ac97_slotid = 0x0b0a0100;	// SCRSA.PRSS[4:0]=1(=>slot4, right PCM playback).
+					// SCRSA.PLSS[4:0]=0(=>slot3, left PCM playback).
+					// SCRSA.CRSS[4:0]=11(=>slot11, right PCM record)
+					// SCRSA.CLSS[4:0]=10(=>slot10, left PCM record).
+	writel(ac97_slotid, card->pBA0 + BA0_SRCSA);                // (75ch)
+
+	// Set 'Half Terminal Count Interrupt Enable' and 'Terminal
+	// Count Interrupt Enable' in DMA Control Registers 0 & 1.
+	// Set 'MSK' flag to 1 to keep the DMA engines paused.
+	temp1 = (DCRn_HTCIE | DCRn_TCIE | DCRn_MSK);	 // (00030001h)
+	writel(temp1, card->pBA0 + BA0_DCR0);            // (154h
+	writel(temp1, card->pBA0 + BA0_DCR1);            // (15ch)
+
+	// Set 'Auto-Initialize Control' to 'enabled'; For playback,
+	// set 'Transfer Type Control'(TR[1:0]) to 'read transfer',
+	// for record, set Transfer Type Control to 'write transfer'.
+	// All other bits set to zero;  Some will be changed @ transfer start.
+	temp1 = (DMRn_DMA | DMRn_AUTO | DMRn_TR_READ);   // (20000018h)
+	writel(temp1, card->pBA0 + BA0_DMR0);            // (150h)
+	temp1 = (DMRn_DMA | DMRn_AUTO | DMRn_TR_WRITE);  // (20000014h)
+	writel(temp1, card->pBA0 + BA0_DMR1);            // (158h)
+
+	// Enable DMA interrupts generally, and
+	// DMA0 & DMA1 interrupts specifically.
+	temp1 = readl(card->pBA0 + BA0_HIMR) &  0xfffbfcff;
+	writel(temp1, card->pBA0+BA0_HIMR);
+
+	CS_DBGOUT(CS_FUNCTION, 2, printk(KERN_INFO "cs4281: cs4281_hw_init()- 0\n") );
+	return 0;
+}
+
+
+//******************************************************************************
+// "cs4281_play_rate()" --
+//******************************************************************************
+static void cs4281_play_rate(struct cs4281_state *card, u32 playrate)
+{
+	u32 DACSRvalue = 1;
+
+	 // Based on the sample rate, program the DACSR register.
+	if(playrate == 8000)
+		DACSRvalue = 5;
+	if(playrate == 11025)
+		DACSRvalue = 4;
+	else if(playrate == 22050)
+		DACSRvalue = 2;
+	else if(playrate == 44100)
+		DACSRvalue = 1;
+	else if((playrate <= 48000) && (playrate >= 6023))
+		DACSRvalue = 24576000/(playrate*16);
+	else if(playrate < 6023)
+		// Not allowed by open.
+		return;
+	else if(playrate > 48000)
+		// Not allowed by open.
+		return;
+	CS_DBGOUT(CS_WAVE_WRITE | CS_PARMS, 2, printk(KERN_INFO 
+		"cs4281: cs4281_play_rate(): DACSRvalue=0x%.8x playrate=%d\n",
+			DACSRvalue,playrate));
+	 //  Write the 'sample rate select code'
+	 //  to the 'DAC Sample Rate' register.
+	writel(DACSRvalue, card->pBA0 + BA0_DACSR);           // (744h)
+}
+
+//******************************************************************************
+// "cs4281_record_rate()" -- Initialize the record sample rate converter.
+//******************************************************************************
+static void cs4281_record_rate(struct cs4281_state *card, u32 outrate)
+{
+	u32 ADCSRvalue = 1;
+
+	 //
+	 // Based on the sample rate, program the ADCSR register
+	 //
+	if(outrate == 8000)
+		ADCSRvalue = 5;
+	if(outrate == 11025)
+		ADCSRvalue = 4;
+	else if(outrate == 22050)
+		ADCSRvalue = 2;
+	else if(outrate == 44100)
+		ADCSRvalue = 1;
+	else if((outrate <= 48000) && (outrate >= 6023))
+		ADCSRvalue = 24576000/(outrate*16);
+	else if(outrate < 6023)
+	{
+		// Not allowed by open.
+		return;
+	}
+	else if(outrate > 48000)
+	{
+		// Not allowed by open.
+		return;
+	}
+	CS_DBGOUT(CS_WAVE_READ | CS_PARMS, 2, printk(KERN_INFO 
+		"cs4281: cs4281_record_rate(): ADCSRvalue=0x%.8x outrate=%d\n",
+			ADCSRvalue,outrate) );
+	//  Write the 'sample rate select code
+	//  to the 'ADC Sample Rate' register.
+	writel(ADCSRvalue, card->pBA0 + BA0_ADCSR);           // (748h)
+}
+
+
+
+static void stop_dac(struct cs4281_state *s)
+{
+	unsigned long flags;
+	unsigned temp1;
+
+	CS_DBGOUT(CS_WAVE_WRITE, 3, printk(KERN_INFO "cs4281: stop_dac():\n") );
+	spin_lock_irqsave(&s->lock, flags);
+	s->ena &= ~FMODE_WRITE;
+	temp1 = readl(s->pBA0+ BA0_DCR0) | DCRn_MSK;     
+	writel(temp1, s->pBA0+BA0_DCR0);         
+
+	spin_unlock_irqrestore(&s->lock, flags);
+}
+
+
+static void start_dac(struct cs4281_state *s)
+{
+	unsigned long flags;
+	unsigned temp1;
+
+	CS_DBGOUT(CS_WAVE_WRITE, 3, printk(KERN_INFO "cs4281: start_dac():\n") );
+	spin_lock_irqsave(&s->lock, flags);
+	if (!(s->ena & FMODE_WRITE) && (s->dma_dac.mapped ||
+	      s->dma_dac.count > 0) && s->dma_dac.ready)      {
+		s->ena |= FMODE_WRITE;
+		temp1 = readl(s->pBA0+BA0_DCR0) & ~DCRn_MSK;     // Clear DMA0 channel mask.
+		writel(temp1, s->pBA0+BA0_DCR0);                 // Start DMA'ing.
+		writel(HICR_IEV | HICR_CHGM, s->pBA0+BA0_HICR);     // Enable interrupts.              
+	
+		writel(7, s->pBA0+BA0_PPRVC);
+		writel(7, s->pBA0+BA0_PPLVC);
+	
+	}
+	spin_unlock_irqrestore(&s->lock, flags);
+}
+
+
+static void stop_adc(struct cs4281_state *s)
+{
+	unsigned long flags;
+	unsigned temp1;
+
+	CS_DBGOUT(CS_WAVE_READ, 3, printk(KERN_INFO "cs4281: stop_adc():\n") );
+
+	spin_lock_irqsave(&s->lock, flags);
+	s->ena &= ~FMODE_READ;
+	temp1 = readl(s->pBA0+ BA0_DCR1) | DCRn_MSK;     
+	writel(temp1, s->pBA0+BA0_DCR1);
+	spin_unlock_irqrestore(&s->lock, flags);
+}
+
+
+static void start_adc(struct cs4281_state *s)
+{
+	unsigned long flags;
+	unsigned temp1;
+
+	CS_DBGOUT(CS_WAVE_WRITE, 3, printk(KERN_INFO "cs4281: start_adc():\n") );
+
+	spin_lock_irqsave(&s->lock, flags);
+	if (!(s->ena & FMODE_READ) && (s->dma_adc.mapped
+	      || s->dma_adc.count <= 
+		 (signed)(s->dma_adc.dmasize - 2*s->dma_adc.fragsize))
+	      && s->dma_adc.ready)
+	{
+		s->ena |= FMODE_READ;
+		temp1 = readl(s->pBA0+BA0_DCR1) & ~ DCRn_MSK;         // Clear DMA1 channel mask bit.
+		writel(temp1, s->pBA0+BA0_DCR1);                      // Start recording
+		writel(HICR_IEV | HICR_CHGM, s->pBA0+BA0_HICR);       // Enable interrupts.
+	}
+	spin_unlock_irqrestore(&s->lock, flags);
+
+}
+
+
+// --------------------------------------------------------------------- 
+#define DMABUF_DEFAULTORDER (15-PAGE_SHIFT)     // == 3(for PC), = log base 2( buff sz = 32k).
+#define DMABUF_MINORDER 1                       // ==> min buffer size = 8K.
+
+
+extern  void dealloc_dmabuf(struct cs4281_state *s, struct dmabuf *db)
+{
+	struct page *map, *mapend;
+
+	if (db->rawbuf) {
+		// Undo prog_dmabuf()'s marking the pages as reserved 
+		mapend = virt_to_page(db->rawbuf + (PAGE_SIZE << db->buforder) - 1);
+		for (map = virt_to_page(db->rawbuf); map <= mapend; map++)
+			clear_bit(PG_reserved, &map->flags);
+		pci_free_consistent(s->pcidev,PAGE_SIZE<<db->buforder,
+			db->rawbuf,db->dmaaddr);
+	}
+	db->rawbuf = NULL;
+	db->mapped = db->ready = 0;
+}
+
+static int prog_dmabuf(struct cs4281_state *s, struct dmabuf *db)
+{
+	int order;
+	unsigned bytespersec, temp1;
+	unsigned bufs, sample_shift = 0;
+	struct page *map, *mapend;
+
+	db->hwptr = db->swptr = db->total_bytes = db->count = 
+		db->error = db->endcleared = db->blocks = 0;
+	if (!db->rawbuf) {
+		db->ready = db->mapped = 0;
+		for (order = DMABUF_DEFAULTORDER; order >= DMABUF_MINORDER; order--)
+			if ((db->rawbuf = (void *)pci_alloc_consistent(
+				s->pcidev, PAGE_SIZE << order, &db->dmaaddr)))
+				break;
+		if (!db->rawbuf)
+		{
+			CS_DBGOUT(CS_ERROR, 1, printk(KERN_ERR 
+				"cs4281: prog_dmabuf(): unable to allocate rawbuf\n") );
+			return -ENOMEM;
+		}
+		db->buforder = order;
+		// Now mark the pages as reserved; otherwise the 
+		// remap_page_range() in cs4281_mmap doesn't work.
+		     // 1. get index to last page in mem_map array for rawbuf.
+		mapend = virt_to_page(db->rawbuf + (PAGE_SIZE << db->buforder) - 1);
+		
+		     // 2. mark each physical page in range as 'reserved'.
+		for (map = virt_to_page(db->rawbuf); map <= mapend; map++)
+			set_bit(PG_reserved, &map->flags);
+	}
+	if (s->fmt & (AFMT_S16_LE | AFMT_U16_LE))
+		sample_shift++;
+	if (s->channels > 1)
+		sample_shift++;
+	bytespersec = s->rate << sample_shift;
+	bufs = PAGE_SIZE << db->buforder;
+
+
+#define INTERRUPT_RATE_MS       100                      // Interrupt rate in milliseconds.
+	db->numfrag = 2;
+	temp1 = bytespersec/(1000/INTERRUPT_RATE_MS);    // Nominal frag size(bytes/interrupt)
+	db->fragshift = 8;                               // Min 256 bytes.
+	while( 1 << db->fragshift  < temp1)              // Calc power of 2 frag size.
+		db->fragshift +=1;
+	db->fragsize = 1 << db->fragshift;               
+	db->dmasize = db->fragsize * 2;
+ 
+		// If the calculated size is larger than the allocated
+		//  buffer, divide the allocated buffer into 2 fragments.
+	if(db->dmasize > bufs) {
+		db->numfrag = 2;                                 // Two fragments.
+		db->fragsize = bufs >> 1;                        // Each 1/2 the alloc'ed buffer.
+		db->fragsamples = db->fragsize >> sample_shift;  // # samples/fragment.
+		db->dmasize =  bufs;                             // Use all the alloc'ed buffer.
+		
+		db->fragshift = 0;                               // Calculate 'fragshift'.
+		temp1 = db->fragsize;                            // update_ptr() uses it 
+		while( (temp1 >>=1) > 1)                         // to calc 'total-bytes'
+		     db->fragshift +=1;                          // returned in DSP_GETI/OPTR. 
+	}
+	CS_DBGOUT(CS_PARMS, 3, printk(KERN_INFO 
+		    "cs4281: prog_dmabuf(): numfrag=%d fragsize=%d fragsamples=%d fragshift=%d\n",
+			db->numfrag,db->fragsize,db->fragsamples,db->fragshift) );
+	return 0;
+}    
+
+
+static int prog_dmabuf_adc(struct cs4281_state *s)
+{
+	unsigned long va;
+	unsigned count;      
+	int c;
+	stop_adc(s);
+	if ((c = prog_dmabuf(s, &s->dma_adc)))
+		return c;
+	     
+	va = virt_to_bus(s->dma_adc.rawbuf);
+	
+	count = s->dma_adc.dmasize;       
+       
+	if(s->fmt & (AFMT_S16_LE | AFMT_U16_LE | AFMT_S16_BE | AFMT_U16_BE))
+		count /= 2;                      // 16-bit.
+			
+	if(s->channels > 1)
+		count /= 2;                      // Assume stereo.
+	  
+	CS_DBGOUT(CS_WAVE_READ, 3, printk(KERN_INFO 
+	    "cs4281: prog_dmabuf_adc(): count=%d va=0x%.8x\n", count,(unsigned)va) );
+
+	writel(va, s->pBA0+BA0_DBA1);            // Set buffer start address.
+	writel(count-1, s->pBA0+BA0_DBC1);       // Set count. 
+	s->dma_adc.ready = 1;
+	return 0;
+}
+
+
+static int prog_dmabuf_dac(struct cs4281_state *s)
+{
+	unsigned long va;
+	unsigned count;
+	int c;
+	stop_dac(s);
+	if ((c = prog_dmabuf(s, &s->dma_dac)))
+		return c;
+	memset(s->dma_dac.rawbuf, (s->fmt & (AFMT_U8 | AFMT_U16_LE))
+				   ? 0x80 : 0, s->dma_dac.dmasize);      
+
+	va = virt_to_bus(s->dma_dac.rawbuf);
+
+	count = s->dma_dac.dmasize;       
+	if(s->fmt & (AFMT_S16_LE | AFMT_U16_LE | AFMT_S16_BE | AFMT_U16_BE))
+		count /= 2;                      // 16-bit.
+      
+	if(s->channels > 1)
+		count /= 2;                      // Assume stereo.
+	   
+	writel(va, s->pBA0+BA0_DBA0);               // Set buffer start address.
+	writel(count-1, s->pBA0+BA0_DBC0);       // Set count.             
+
+	CS_DBGOUT(CS_WAVE_WRITE, 3, printk(KERN_INFO 
+	    "cs4281: prog_dmabuf_dac(): count=%d va=0x%.8x\n", count,(unsigned)va) );
+
+	s->dma_dac.ready = 1;
+	return 0;
+}
+
+
+static void clear_advance(void *buf, unsigned bsize, unsigned bptr, unsigned len, unsigned char c)
+{
+	if (bptr + len > bsize) {
+		unsigned x = bsize - bptr;
+		memset(((char *)buf) + bptr, c, x);
+		bptr = 0;
+		len -= x;
+	}
+	CS_DBGOUT(CS_WAVE_WRITE, 4, printk(KERN_INFO 
+	    "cs4281: clear_advance(): memset %d at 0x%.8x for %d size \n", 
+		(unsigned)c,(unsigned)((char *)buf) + bptr, len) );
+	memset(((char *)buf) + bptr, c, len);
+}
+
+
+
+// call with spinlock held! 
+static void cs4281_update_ptr(struct cs4281_state *s)
+{
+	int diff;
+	unsigned hwptr, va, temp1;
+
+	// update ADC pointer 
+	if (s->ena & FMODE_READ) {
+		hwptr = readl(s->pBA0+BA0_DCA1);          // Read capture DMA address.
+		va = virt_to_bus(s->dma_adc.rawbuf);
+		hwptr -= (unsigned)va;                 
+		diff = (s->dma_adc.dmasize + hwptr - s->dma_adc.hwptr) % s->dma_adc.dmasize;
+		s->dma_adc.hwptr = hwptr;
+		s->dma_adc.total_bytes += diff;
+		s->dma_adc.count += diff;
+		if (s->dma_adc.mapped) {
+			if (s->dma_adc.count >= (signed)s->dma_adc.fragsize)
+				wake_up(&s->dma_adc.wait);
+		} else {
+			if (s->dma_adc.count > 0)
+				wake_up(&s->dma_adc.wait);
+		}
+		CS_DBGOUT(CS_PARMS, 8, printk(KERN_INFO 
+		  "cs4281: cs4281_update_ptr(): s=0x%.8x hwptr=%d total_bytes=%d count=%d \n", 
+		     (unsigned)s,s->dma_adc.hwptr,s->dma_adc.total_bytes,s->dma_adc.count) );
+	}
+	// update DAC pointer 
+	//
+	// check for end of buffer, means that we are going to wait for another interrupt
+	// to allow silence to fill the fifos on the part, to keep pops down to a minimum.
+	//
+	if ( (s->ena & FMODE_WRITE) && (!s->endofbuffer) )
+	{
+		hwptr = readl(s->pBA0+BA0_DCA0);          // Read play DMA address.
+		va = virt_to_bus(s->dma_dac.rawbuf);
+		hwptr -= (unsigned)va;
+		diff = (s->dma_dac.dmasize + hwptr - s->dma_dac.hwptr) % s->dma_dac.dmasize;
+		s->dma_dac.hwptr = hwptr;
+		s->dma_dac.total_bytes += diff;
+		if (s->dma_dac.mapped) {
+			s->dma_dac.count += diff;
+			if (s->dma_dac.count >= (signed)s->dma_dac.fragsize)
+				wake_up(&s->dma_dac.wait);
+		} else {
+			s->dma_dac.count -= diff;
+			if (s->dma_dac.count <= 0) {
+				s->ena &= ~FMODE_WRITE;
+				temp1 = readl(s->pBA0+BA0_DCR0);
+			//
+			// fill with silence, and wait on turning off the DAC until interrupt routine.
+			// wait on "Poke(pBA0+BA0_DCR0, temp1 | DCRn_MSK);    // Stop Play DMA"
+			//
+				CS_DBGOUT(CS_WAVE_WRITE, 6, printk(KERN_INFO 
+				    "cs4281: cs4281_update_ptr(): memset %d at 0x%.8x for %d size \n", 
+					(unsigned)(s->fmt & (AFMT_U8 | AFMT_U16_LE)) ? 0x80 : 0, 
+					(unsigned)s->dma_dac.rawbuf, s->dma_dac.dmasize) );
+				memset(s->dma_dac.rawbuf, (s->fmt & (AFMT_U8 | AFMT_U16_LE)) ? 0x80 : 0, 
+					s->dma_dac.dmasize); 
+				s->endofbuffer = 1;
+			} else if (s->dma_dac.count <= (signed)s->dma_dac.fragsize
+							 && !s->dma_dac.endcleared) {
+				clear_advance(s->dma_dac.rawbuf, 
+					      s->dma_dac.dmasize, s->dma_dac.swptr,
+					      s->dma_dac.fragsize,
+					      (s->fmt & (AFMT_U8 | AFMT_U16_LE)) ? 0x80 : 0);
+				s->dma_dac.endcleared = 1;
+			}
+			if (s->dma_dac.count < (signed)s->dma_dac.dmasize)
+				wake_up(&s->dma_dac.wait);
+		}
+		CS_DBGOUT(CS_PARMS, 8, printk(KERN_INFO 
+		  "cs4281: cs4281_update_ptr(): s=0x%.8x hwptr=%d total_bytes=%d count=%d \n", 
+		     (unsigned)s,s->dma_dac.hwptr,s->dma_dac.total_bytes,s->dma_dac.count) );
+	}
+}
+
+
+// --------------------------------------------------------------------- 
+
+static void prog_codec(struct cs4281_state *s)
+{
+	unsigned long flags;
+	unsigned temp1, format;
+
+	CS_DBGOUT(CS_INIT | CS_FUNCTION, 2, printk(KERN_INFO "cs4281: prog_codec()+ \n") );
+
+	spin_lock_irqsave(&s->lock, flags);
+	temp1 = readl(s->pBA0+BA0_DCR0);
+	writel(temp1 | DCRn_MSK, s->pBA0+BA0_DCR0);   // Stop play DMA, if active.
+	temp1 = readl(s->pBA0+BA0_DCR1);
+	writel(temp1 | DCRn_MSK, s->pBA0+BA0_DCR1);   // Stop capture DMA, if active.
+ 
+	// program sampling rates  
+	// Note, for CS4281, capture & play rates can be set independently.
+	cs4281_record_rate(s, s->rate); 
+	       
+	// program ADC parameters 
+	format = DMRn_DMA | DMRn_AUTO | DMRn_TR_WRITE;
+	if(s->fmt & (AFMT_S16_LE | AFMT_U16_LE | AFMT_S16_BE | AFMT_U16_BE)) { // 16-bit
+	if(s->fmt & (AFMT_S16_BE | AFMT_U16_BE))  // Big-endian?
+		format |= DMRn_BEND;  
+		if(s->fmt & (AFMT_U16_LE  | AFMT_U16_BE)) 
+			format |= DMRn_USIGN;         // Unsigned.      
+	}          
+	else
+		format |= DMRn_SIZE8 | DMRn_USIGN;    // 8-bit, unsigned
+	if(s->channels < 2)
+		format |= DMRn_MONO;
+
+	writel(format, s->pBA0+BA0_DMR1);       
+       
+  
+	// program DAC parameters 
+	format = DMRn_DMA | DMRn_AUTO | DMRn_TR_READ;
+	if(s->fmt & (AFMT_S16_LE | AFMT_U16_LE | AFMT_S16_BE | AFMT_U16_BE)) { // 16-bit
+		if(s->fmt & (AFMT_S16_BE | AFMT_U16_BE))  
+			format |= DMRn_BEND;          // Big Endian.
+		if(s->fmt & (AFMT_U16_LE  | AFMT_U16_BE)) 
+			format |= DMRn_USIGN;         // Unsigned.      
+	}          
+	else
+		format |= DMRn_SIZE8 | DMRn_USIGN;    // 8-bit, unsigned
+	
+	if(s->channels < 2)
+		format |= DMRn_MONO;
+
+	writel(format, s->pBA0+BA0_DMR0);       
+
+	CS_DBGOUT(CS_PARMS, 2, printk(KERN_INFO 
+	    "cs4281: prog_codec(): format=0x%.8x rate=%d\n", format,s->rate) );
+
+	cs4281_play_rate(s, s->rate);
+
+	s->ena = 0;     // Neither writing or reading.
+	spin_unlock_irqrestore(&s->lock, flags);
+}
+
+
+// --------------------------------------------------------------------- 
+
+static const char invalid_magic[] = KERN_CRIT "cs4281: invalid magic value\n";
+
+#define VALIDATE_STATE(s)                         \
+({                                                \
+	if (!(s) || (s)->magic != CS4281_MAGIC) { \
+		printk(invalid_magic);            \
+		return -ENXIO;                    \
+	}                                         \
+})
+
+// --------------------------------------------------------------------- 
+
+
+static int mixer_ioctl(struct cs4281_state *s, unsigned int cmd, unsigned long arg)
+{
+	// Index to mixer_src[] is value of AC97 Input Mux Select Reg.
+	// Value of array member is recording source Device ID Mask.
+	static const unsigned int mixer_src[8] = {
+		SOUND_MASK_MIC, SOUND_MASK_CD, 0, SOUND_MASK_LINE1,
+		SOUND_MASK_LINE, SOUND_MASK_VOLUME, 0, 0
+	};
+	     
+	// Index of mixtable1[] member is Device ID 
+	// and must be <= SOUND_MIXER_NRDEVICES.
+	// Value of array member is index into s->mix.vol[]
+	static const unsigned char mixtable1[SOUND_MIXER_NRDEVICES] = {
+		[SOUND_MIXER_PCM]     = 1,   // voice 
+		[SOUND_MIXER_LINE1]   = 2,   // AUX
+		[SOUND_MIXER_CD]      = 3,   // CD 
+		[SOUND_MIXER_LINE]    = 4,   // Line 
+		[SOUND_MIXER_SYNTH]   = 5,   // FM
+		[SOUND_MIXER_MIC]     = 6,   // Mic 
+		[SOUND_MIXER_SPEAKER] = 7,   // Speaker 
+		[SOUND_MIXER_RECLEV]  = 8,   // Recording level 
+		[SOUND_MIXER_VOLUME]  = 9    // Master Volume 
+	};
+	
+	
+	static const unsigned mixreg[] = {
+		BA0_AC97_PCM_OUT_VOLUME,
+		BA0_AC97_AUX_VOLUME, 
+		BA0_AC97_CD_VOLUME, 
+		BA0_AC97_LINE_IN_VOLUME
+	};
+	unsigned char l, r, rl, rr, vidx;
+	unsigned char attentbl[11] = {63,42,26,17,14,11,8,6,4,2,0};
+	unsigned temp1;
+	int i, val;
+
+	VALIDATE_STATE(s);
+ 
+	if (cmd == SOUND_MIXER_PRIVATE1) {
+		// enable/disable/query mixer preamp 
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		if (val != -1) {
+			cs4281_read_ac97(s, BA0_AC97_MIC_VOLUME, &temp1);
+			temp1 = val ? (temp1 | 0x40) : (temp1 & 0xffbf);
+			cs4281_write_ac97(s, BA0_AC97_MIC_VOLUME, temp1);
+		}
+		cs4281_read_ac97(s, BA0_AC97_MIC_VOLUME, &temp1);
+		val = (temp1 & 0x40) ? 1 : 0;
+		return put_user(val, (int *)arg);
+	}
+	if (cmd == SOUND_MIXER_PRIVATE2) {
+		// enable/disable/query spatializer 
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		if (val != -1) {
+			temp1 = (val & 0x3f) >> 2;
+			cs4281_write_ac97(s, BA0_AC97_3D_CONTROL, temp1);
+			cs4281_read_ac97(s, BA0_AC97_GENERAL_PURPOSE, &temp1);
+			cs4281_write_ac97(s, BA0_AC97_GENERAL_PURPOSE,temp1 | 0x2000);
+		}
+		cs4281_read_ac97(s, BA0_AC97_3D_CONTROL, &temp1);
+		return put_user((temp1 << 2) | 3, (int *)arg);
+	}
+	if (cmd == SOUND_MIXER_INFO) {
+		mixer_info info;
+		strncpy(info.id, "CS4281", sizeof(info.id));
+		strncpy(info.name, "Crystal CS4281", sizeof(info.name));
+		info.modify_counter = s->mix.modcnt;
+		if (copy_to_user((void *)arg, &info, sizeof(info)))
+			return -EFAULT;
+		return 0;
+	}
+	if (cmd == SOUND_OLD_MIXER_INFO) {
+		_old_mixer_info info;
+		strncpy(info.id, "CS4281", sizeof(info.id));
+		strncpy(info.name, "Crystal CS4281", sizeof(info.name));
+		if (copy_to_user((void *)arg, &info, sizeof(info)))
+			return -EFAULT;
+		return 0;
+	}
+	if (cmd == OSS_GETVERSION)
+		return put_user(SOUND_VERSION, (int *)arg);
+	
+	if (_IOC_TYPE(cmd) != 'M' || _IOC_SIZE(cmd) != sizeof(int))
+		return -EINVAL;
+	
+	     // If ioctl has only the IOC_READ bit(bit 31)
+	     // on, process the only-read commands. 
+	if (_IOC_DIR(cmd) == _IOC_READ) {
+		switch (_IOC_NR(cmd)) {
+		case SOUND_MIXER_RECSRC: // Arg contains a bit for each recording source 
+		    cs4281_read_ac97(s, BA0_AC97_RECORD_SELECT, &temp1);
+		    return put_user(mixer_src[temp1 & 7], (int *)arg);
+
+		case SOUND_MIXER_DEVMASK: // Arg contains a bit for each supported device 
+			return put_user(SOUND_MASK_PCM | SOUND_MASK_SYNTH | SOUND_MASK_CD |
+					SOUND_MASK_LINE | SOUND_MASK_LINE1 | SOUND_MASK_MIC |
+					SOUND_MASK_VOLUME | SOUND_MASK_RECLEV |
+					SOUND_MASK_SPEAKER, (int *)arg);
+
+		case SOUND_MIXER_RECMASK: // Arg contains a bit for each supported recording source 
+			return put_user(SOUND_MASK_LINE | SOUND_MASK_MIC | SOUND_MASK_CD 
+				      | SOUND_MASK_VOLUME | SOUND_MASK_LINE1, (int *)arg);
+
+		case SOUND_MIXER_STEREODEVS: // Mixer channels supporting stereo 
+			return put_user(SOUND_MASK_PCM | SOUND_MASK_SYNTH | SOUND_MASK_CD |
+					SOUND_MASK_LINE | SOUND_MASK_LINE1 | SOUND_MASK_MIC |
+					SOUND_MASK_VOLUME | SOUND_MASK_RECLEV, (int *)arg);
+
+		case SOUND_MIXER_CAPS:
+			return put_user(SOUND_CAP_EXCL_INPUT, (int *)arg);
+
+		default:
+			i = _IOC_NR(cmd);
+			if (i >= SOUND_MIXER_NRDEVICES || !(vidx = mixtable1[i]))
+				return -EINVAL;
+			return put_user(s->mix.vol[vidx-1], (int *)arg);
+		}
+	}
+	
+	     // If ioctl doesn't have both the IOC_READ and 
+	     // the IOC_WRITE bit set, return invalid.
+	if (_IOC_DIR(cmd) != (_IOC_READ|_IOC_WRITE))
+		return -EINVAL;
+	
+	     // Increment the count of volume writes.
+	s->mix.modcnt++;
+	     
+	     // Isolate the command; it must be a write.
+	switch (_IOC_NR(cmd)) {
+	
+	case SOUND_MIXER_RECSRC: // Arg contains a bit for each recording source 
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		i = hweight32(val);                 // i = # bits on in val.
+		if (i != 1)                         // One & only 1 bit must be on.
+			return 0;
+		for(i=0; i<sizeof(mixer_src)/sizeof(int); i++) {
+			if(val == mixer_src[i]) {
+				temp1 = (i << 8) | i;  
+				cs4281_write_ac97(s, BA0_AC97_RECORD_SELECT, temp1);
+				return 0;
+			}
+		}
+		return 0;
+
+	case SOUND_MIXER_VOLUME:
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		l = val & 0xff;
+		if(l > 100)
+			l = 100;                    // Max soundcard.h vol is 100.
+		if(l < 6) {
+			rl = 63;
+			l  = 0;
+		}
+		else 
+			rl = attentbl[(10*l)/100];  // Convert 0-100 vol to 63-0 atten.
+			
+			r = (val >> 8) & 0xff;
+			if (r > 100)
+				r = 100;            // Max right volume is 100, too
+			if(r < 6) {
+				rr = 63;
+				r  = 0;
+			}
+			else 
+			       rr = attentbl[(10*r)/100];   // Convert volume to attenuation.
+		
+		if ((rl > 60 ) && (rr > 60))        // If both l & r are 'low',          
+			temp1 = 0x8000;             //  turn on the mute bit.
+		else
+			temp1 = 0;
+		
+		temp1 |= (rl << 8) | rr;
+		
+		cs4281_write_ac97(s, BA0_AC97_MASTER_VOLUME, temp1);
+		cs4281_write_ac97(s, BA0_AC97_HEADPHONE_VOLUME, temp1);
+
+#ifdef OSS_DOCUMENTED_MIXER_SEMANTICS
+		s->mix.vol[8] = ((unsigned int)r << 8) | l;
+#else
+		s->mix.vol[8] = val;
+#endif
+		return put_user(s->mix.vol[8], (int *)arg);
+
+	case SOUND_MIXER_SPEAKER:
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		l = val & 0xff;
+		if (l > 100)
+			l = 100;
+		if(l < 3 ) {
+			rl = 0;
+			l = 0;
+		}
+		else {
+			rl = (l*2 - 5)/13;          // Convert 0-100 range to 0-15.
+			l = (rl*13 +5)/2;
+		}
+
+		if (rl < 3){
+		       temp1 = 0x8000;
+		       rl     = 0;
+		}
+		else
+		       temp1 = 0;
+		rl = 15 - rl;                       // Convert volume to attenuation.
+		temp1 |= rl << 1;
+		cs4281_write_ac97(s, BA0_AC97_PC_BEEP_VOLUME, temp1);
+
+#ifdef OSS_DOCUMENTED_MIXER_SEMANTICS
+		s->mix.vol[6] = l << 8;
+#else
+		s->mix.vol[6] = val;
+#endif
+		return put_user(s->mix.vol[6], (int *)arg);
+
+	case SOUND_MIXER_RECLEV:
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		l = val & 0xff;
+		if (l > 100)
+			l = 100;
+		r = (val >> 8) & 0xff;
+		if (r > 100)
+			r = 100;
+		rl = (l*2 - 5) / 13;                // Convert 0-100 scale to 0-15.
+		rr = (r*2 - 5) / 13;
+		if (rl <3 && rr <3)
+			temp1 = 0x8000;
+		else
+			temp1 = 0;
+
+		temp1 = temp1 | (rl << 8) | rr;
+		cs4281_write_ac97(s, BA0_AC97_RECORD_GAIN, temp1); 
+
+#ifdef OSS_DOCUMENTED_MIXER_SEMANTICS
+		s->mix.vol[7] = ((unsigned int)r << 8) | l;
+#else
+		s->mix.vol[7] = val;
+#endif
+		return put_user(s->mix.vol[7], (int *)arg);
+
+	case SOUND_MIXER_MIC:
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		l = val & 0xff;
+		if (l > 100)
+			l = 100;
+		if (l < 1) {
+			l = 0;
+			rl = 0;
+		}
+		else {
+			rl = ((unsigned)l*5 - 4)/16; // Convert 0-100 range to 0-31.
+			l  = (rl*16 +4)/5;
+		}
+		cs4281_read_ac97(s, BA0_AC97_MIC_VOLUME, &temp1);
+		temp1 &= 0x40;                      // Isolate 20db gain bit.
+		if (rl < 3){
+		       temp1 |= 0x8000;
+		       rl     = 0;
+		}
+		rl = 31 - rl;                       // Convert volume to attenuation.
+		temp1 |= rl; 
+		cs4281_write_ac97(s, BA0_AC97_MIC_VOLUME, temp1);
+
+#ifdef OSS_DOCUMENTED_MIXER_SEMANTICS
+		s->mix.vol[5] = val << 8;
+#else
+		s->mix.vol[5] = val;
+#endif
+		return put_user(s->mix.vol[5], (int *)arg);
+	
+	
+	case SOUND_MIXER_SYNTH:
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		l = val & 0xff;
+		if (l > 100)
+			l = 100;
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		r = (val >> 8) & 0xff;
+		if (r > 100)
+			r = 100;
+		rl = (l * 2 - 11)/3;        // Convert 0-100 range to 0-63.
+		rr = (r * 2 - 11)/3;
+		if (rl < 3)                 // If l is low, turn on
+			temp1 = 0x0080;     //  the mute bit.
+		else
+			temp1 = 0;
+
+		rl = 63 - rl;               // Convert vol to attenuation.
+		writel(temp1|rl, s->pBA0+BA0_FMLVC);
+		if (rr < 3)                 //  If rr is low, turn on
+			temp1 = 0x0080;     //   the mute bit.
+		else
+			temp1 = 0;
+		rr = 63 - rr;               // Convert vol to attenuation.
+		writel(temp1 | rr, s->pBA0+BA0_FMRVC);
+
+#ifdef OSS_DOCUMENTED_MIXER_SEMANTICS
+		s->mix.vol[4] = (r << 8) | l;
+#else
+		s->mix.vol[4] = val;
+#endif
+		return put_user(s->mix.vol[4], (int *)arg);
+
+		
+	default:
+		i = _IOC_NR(cmd);
+		if (i >= SOUND_MIXER_NRDEVICES || !(vidx = mixtable1[i]))
+			return -EINVAL;
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		l = val & 0xff;
+		if (l > 100)
+			l = 100;
+		if (l < 1) {
+			l = 0;
+			rl = 31;
+		}
+		else 
+			rl = (attentbl[(l*10)/100])>>1;
+		
+		r = (val >> 8) & 0xff;
+		if (r > 100)
+			r = 100;
+		if (r < 1) {
+			r = 0;
+			rr = 31;
+		}
+		else 
+			rr = (attentbl[(r*10)/100])>>1;                        
+		if ((rl > 30) && (rr > 30))
+			temp1 = 0x8000;
+		else
+			temp1 = 0;
+		temp1 = temp1 | (rl << 8) | rr;              
+		cs4281_write_ac97(s, mixreg[vidx-1], temp1);
+		
+#ifdef OSS_DOCUMENTED_MIXER_SEMANTICS
+		s->mix.vol[vidx-1] = ((unsigned int)r << 8) | l;
+#else
+		s->mix.vol[vidx-1] = val;
+#endif
+		return put_user(s->mix.vol[vidx-1], (int *)arg);
+	}
+}
+
+
+// --------------------------------------------------------------------- 
+
+static loff_t cs4281_llseek(struct file *file, loff_t offset, int origin)
+{
+	return -ESPIPE;
+}
+
+
+// --------------------------------------------------------------------- 
+
+static int cs4281_open_mixdev(struct inode *inode, struct file *file)
+{
+	int minor = MINOR(inode->i_rdev);
+	struct cs4281_state *s = devs;
+
+	while (s && s->dev_mixer != minor)
+		s = s->next;
+	if (!s)
+		return -ENODEV;
+	VALIDATE_STATE(s);
+	file->private_data = s;
+	MOD_INC_USE_COUNT;
+	return 0;
+}
+
+
+static int cs4281_release_mixdev(struct inode *inode, struct file *file)
+{
+	struct cs4281_state *s = (struct cs4281_state *)file->private_data;
+
+	VALIDATE_STATE(s);
+	MOD_DEC_USE_COUNT;
+	return 0;
+}
+
+
+static int cs4281_ioctl_mixdev(struct inode *inode, struct file *file,
+			       unsigned int cmd, unsigned long arg)
+{
+	return mixer_ioctl((struct cs4281_state *)file->private_data, cmd, arg);
+}
+
+
+// ******************************************************************************************
+//   Mixer file operations struct.
+// ******************************************************************************************
+static /*const*/ struct file_operations cs4281_mixer_fops = {
+	llseek:		cs4281_llseek,
+	ioctl:		cs4281_ioctl_mixdev,
+	open:		cs4281_open_mixdev,
+	release:	cs4281_release_mixdev,
+};
+
+// --------------------------------------------------------------------- 
+
+static int drain_dac(struct cs4281_state *s, int nonblock)
+{
+	DECLARE_WAITQUEUE(wait, current);
+	unsigned long flags;
+	int count;
+	unsigned tmo;
+
+	if (s->dma_dac.mapped)
+		return 0;
+	current->state = TASK_INTERRUPTIBLE;
+	add_wait_queue(&s->dma_dac.wait, &wait);
+	for (;;) {
+		spin_lock_irqsave(&s->lock, flags);
+		count = s->dma_dac.count;
+		spin_unlock_irqrestore(&s->lock, flags);
+		if (count <= 0)
+			break;
+		if (signal_pending(current))
+			break;
+		if (nonblock) {
+			remove_wait_queue(&s->dma_dac.wait, &wait);
+			current->state = TASK_RUNNING;
+			return -EBUSY;
+		}
+		tmo = 3 * HZ * (count + s->dma_dac.fragsize) / 2 / s->rate;
+		if (s->fmt & (AFMT_S16_LE | AFMT_U16_LE))
+			tmo >>= 1;
+		if (s->channels > 1)
+			tmo >>= 1;
+		if (!schedule_timeout(tmo + 1))
+			printk(KERN_DEBUG "cs4281: dma timed out??\n");
+	}
+	remove_wait_queue(&s->dma_dac.wait, &wait);
+	current->state = TASK_RUNNING;
+	if (signal_pending(current))
+		return -ERESTARTSYS;
+	return 0;
+}
+
+
+// --------------------------------------------------------------------- 
+
+static ssize_t cs4281_read(struct file *file, char *buffer, size_t count, loff_t *ppos)
+{
+	struct cs4281_state *s = (struct cs4281_state *)file->private_data;
+	ssize_t ret;
+	unsigned long flags;
+	unsigned swptr;
+	int cnt;
+
+	CS_DBGOUT(CS_FUNCTION | CS_WAVE_READ, 2, 
+		printk(KERN_INFO "cs4281: cs4281_read()+ \n") );
+
+	VALIDATE_STATE(s);
+	if (ppos != &file->f_pos)
+		return -ESPIPE;
+	if (s->dma_adc.mapped)
+		return -ENXIO;
+	if (!s->dma_adc.ready && (ret = prog_dmabuf_adc(s)))
+		return ret;
+	if (!access_ok(VERIFY_WRITE, buffer, count))
+		return -EFAULT;
+	ret = 0;
+	while (count > 0) {
+		spin_lock_irqsave(&s->lock, flags);
+		swptr = s->dma_adc.swptr;
+		cnt = s->dma_adc.dmasize-swptr;
+		if (s->dma_adc.count < cnt)
+			cnt = s->dma_adc.count;
+		spin_unlock_irqrestore(&s->lock, flags);
+		if (cnt > count)
+			cnt = count;
+		if (cnt <= 0) {
+			start_adc(s);
+			 if (file->f_flags & O_NONBLOCK)
+				return ret ? ret : -EAGAIN;
+			interruptible_sleep_on(&s->dma_adc.wait);
+			if (signal_pending(current))
+				return ret ? ret : -ERESTARTSYS;
+			continue;
+		}
+		if (copy_to_user(buffer, s->dma_adc.rawbuf + swptr, cnt))
+			return ret ? ret : -EFAULT;
+		swptr = (swptr + cnt) % s->dma_adc.dmasize;
+		spin_lock_irqsave(&s->lock, flags);
+		s->dma_adc.swptr = swptr;
+		s->dma_adc.count -= cnt;
+		spin_unlock_irqrestore(&s->lock, flags);
+		count -= cnt;
+		buffer += cnt;
+		ret += cnt;
+		start_adc(s);
+	}
+	CS_DBGOUT(CS_FUNCTION | CS_WAVE_READ, 2, 
+		printk(KERN_INFO "cs4281: cs4281_read()- %d\n",ret) );
+	return ret;
+}
+
+
+static ssize_t cs4281_write(struct file *file, const char *buffer, size_t count, loff_t *ppos)
+{
+	struct cs4281_state *s = (struct cs4281_state *)file->private_data;
+	ssize_t ret;
+	unsigned long flags;
+	unsigned swptr;
+	int cnt;
+
+	CS_DBGOUT(CS_FUNCTION | CS_WAVE_WRITE, 2, 
+		printk(KERN_INFO "cs4281: cs4281_write()+ \n") );
+	VALIDATE_STATE(s);
+
+	if (ppos != &file->f_pos)
+		return -ESPIPE;
+	if (s->dma_dac.mapped)
+		return -ENXIO;
+	if (!s->dma_dac.ready && (ret = prog_dmabuf_dac(s)))
+		return ret;
+	if (!access_ok(VERIFY_READ, buffer, count))
+		return -EFAULT;
+	ret = 0;
+	while (count > 0) {
+		spin_lock_irqsave(&s->lock, flags);
+		if (s->dma_dac.count < 0) {
+			s->dma_dac.count = 0;
+			s->dma_dac.swptr = s->dma_dac.hwptr;
+		}
+		swptr = s->dma_dac.swptr;
+		cnt = s->dma_dac.dmasize-swptr;
+		if (s->dma_dac.count + cnt > s->dma_dac.dmasize)
+			cnt = s->dma_dac.dmasize - s->dma_dac.count;
+		spin_unlock_irqrestore(&s->lock, flags);
+		if (cnt > count)
+			cnt = count;
+		if (cnt <= 0) {
+			start_dac(s);
+			if (file->f_flags & O_NONBLOCK)
+				return ret ? ret : -EAGAIN;
+			interruptible_sleep_on(&s->dma_dac.wait);
+			if (signal_pending(current))
+				return ret ? ret : -ERESTARTSYS;
+			continue;
+		}
+		if (copy_from_user(s->dma_dac.rawbuf + swptr, buffer, cnt))
+			return ret ? ret : -EFAULT;
+		swptr = (swptr + cnt) % s->dma_dac.dmasize;
+		spin_lock_irqsave(&s->lock, flags);
+		s->dma_dac.swptr = swptr;
+		s->dma_dac.count += cnt;
+		s->dma_dac.endcleared = 0;
+		spin_unlock_irqrestore(&s->lock, flags);
+		count -= cnt;
+		buffer += cnt;
+		ret += cnt;
+		start_dac(s);
+	}
+	CS_DBGOUT(CS_FUNCTION | CS_WAVE_WRITE, 2, 
+		printk(KERN_INFO "cs4281: cs4281_write()- %d\n",ret) );
+	return ret;
+}
+
+
+static unsigned int cs4281_poll(struct file *file, struct poll_table_struct *wait)
+{
+	struct cs4281_state *s = (struct cs4281_state *)file->private_data;
+	unsigned long flags;
+	unsigned int mask = 0;
+
+	CS_DBGOUT(CS_FUNCTION | CS_WAVE_WRITE | CS_WAVE_READ, 4, 
+		printk(KERN_INFO "cs4281: cs4281_poll()+\n") );
+	VALIDATE_STATE(s);
+	if (file->f_mode & FMODE_WRITE)
+		poll_wait(file, &s->dma_dac.wait, wait);
+	if (file->f_mode & FMODE_READ)
+		poll_wait(file, &s->dma_adc.wait, wait);
+	spin_lock_irqsave(&s->lock, flags);
+	cs4281_update_ptr(s);
+	if (file->f_mode & FMODE_READ) {
+		if (s->dma_adc.mapped) {
+			if (s->dma_adc.count >= (signed)s->dma_adc.fragsize)
+				mask |= POLLIN | POLLRDNORM;
+		} else {
+			if (s->dma_adc.count > 0)
+				mask |= POLLIN | POLLRDNORM;
+		}
+	}
+	if (file->f_mode & FMODE_WRITE) {
+		if (s->dma_dac.mapped) {
+			if (s->dma_dac.count >= (signed)s->dma_dac.fragsize)
+				mask |= POLLOUT | POLLWRNORM;
+		} else {
+			if ((signed)s->dma_dac.dmasize > s->dma_dac.count)
+				mask |= POLLOUT | POLLWRNORM;
+		}
+	}
+	spin_unlock_irqrestore(&s->lock, flags);
+	CS_DBGOUT(CS_FUNCTION | CS_WAVE_WRITE | CS_WAVE_READ, 4, 
+		printk(KERN_INFO "cs4281: cs4281_poll()- 0x%.8x\n",mask) );
+	return mask;
+}
+
+
+static int cs4281_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct cs4281_state *s = (struct cs4281_state *)file->private_data;
+	struct dmabuf *db;
+	int ret;
+	unsigned long size;
+
+	CS_DBGOUT(CS_FUNCTION | CS_PARMS | CS_OPEN, 4, 
+		printk(KERN_INFO "cs4281: cs4281_mmap()+\n") );
+
+	VALIDATE_STATE(s);
+	if (vma->vm_flags & VM_WRITE) {
+		if ((ret = prog_dmabuf_dac(s)) != 0)
+			return ret;
+		db = &s->dma_dac;
+	} else if (vma->vm_flags & VM_READ) {
+		if ((ret = prog_dmabuf_adc(s)) != 0)
+			return ret;
+		db = &s->dma_adc;
+	} else
+		return -EINVAL;
+	if (vma->vm_pgoff != 0)
+		return -EINVAL;
+	size = vma->vm_end - vma->vm_start;
+	if (size > (PAGE_SIZE << db->buforder))
+		return -EINVAL;
+	if (remap_page_range(vma->vm_start, virt_to_phys(db->rawbuf), size, vma->vm_page_prot))
+		return -EAGAIN;
+	db->mapped = 1;
+
+	CS_DBGOUT(CS_FUNCTION | CS_PARMS | CS_OPEN, 4, 
+		printk(KERN_INFO "cs4281: cs4281_mmap()- 0 size=%d\n",
+			(unsigned)size) );
+
+	return 0;
+}
+
+
+static int cs4281_ioctl(struct inode *inode, struct file *file, unsigned int cmd, unsigned long arg)
+{
+	struct cs4281_state *s = (struct cs4281_state *)file->private_data;
+	unsigned long flags;
+	audio_buf_info abinfo;
+	count_info cinfo;
+	int val, mapped, ret;
+  
+	CS_DBGOUT(CS_FUNCTION, 4, 
+		printk(KERN_INFO "cs4281: cs4281_ioctl(): file=0x%.8x cmd=0x%.8x\n",
+			(unsigned)file,cmd) );
+	VALIDATE_STATE(s);
+	mapped = ((file->f_mode & FMODE_WRITE) && s->dma_dac.mapped) ||
+		((file->f_mode & FMODE_READ) && s->dma_adc.mapped);
+	switch (cmd) {
+	case OSS_GETVERSION:
+		CS_DBGOUT(CS_FUNCTION | CS_PARMS, 4, printk(KERN_INFO 
+			"cs4281: cs4281_ioctl(): SOUND_VERSION=0x%.8x\n", SOUND_VERSION) );
+		return put_user(SOUND_VERSION, (int *)arg);
+
+	case SNDCTL_DSP_SYNC:
+		if (file->f_mode & FMODE_WRITE)
+			return drain_dac(s, 0/*file->f_flags & O_NONBLOCK*/);
+		return 0;
+
+	case SNDCTL_DSP_SETDUPLEX:
+		return 0;
+
+	case SNDCTL_DSP_GETCAPS:
+		return put_user(DSP_CAP_DUPLEX | DSP_CAP_REALTIME | DSP_CAP_TRIGGER | DSP_CAP_MMAP, (int *)arg);
+
+	case SNDCTL_DSP_RESET:
+		if (file->f_mode & FMODE_WRITE) {
+			stop_dac(s);
+			synchronize_irq();
+			s->dma_dac.swptr = s->dma_dac.hwptr = s->dma_dac.count = 
+				s->dma_dac.total_bytes = s->dma_dac.blocks = 0;
+		}
+		if (file->f_mode & FMODE_READ) {
+			stop_adc(s);
+			synchronize_irq();
+			s->dma_adc.swptr = s->dma_adc.hwptr = s->dma_adc.count = 
+				s->dma_adc.total_bytes = s->dma_adc.blocks = 0;
+		}
+		prog_codec(s);
+		return 0;
+
+	case SNDCTL_DSP_SPEED:
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		if (val >= 0) {
+			stop_adc(s);
+			stop_dac(s);
+			s->dma_adc.ready = s->dma_dac.ready = 0;
+			// program sampling rates 
+			if (val > 48000)
+				val = 48000;
+			if (val < 6300)
+				val = 6300;
+			s->rate = val;
+			prog_codec(s);
+		}
+		return put_user(s->rate, (int *)arg);
+
+	case SNDCTL_DSP_STEREO:
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		stop_adc(s);
+		stop_dac(s);
+		s->dma_adc.ready = s->dma_dac.ready = 0;
+		// program channels 
+		s->channels = val ? 2 : 1;
+		prog_codec(s);
+		return 0;
+
+	case SNDCTL_DSP_CHANNELS:
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		if (val != 0) {
+			stop_adc(s);
+			stop_dac(s);
+			s->dma_adc.ready = s->dma_dac.ready = 0;
+			// program channels 
+			s->channels = val ? 2 : 1;
+			prog_codec(s);
+		}
+		return put_user(s->channels, (int *)arg);
+
+	case SNDCTL_DSP_GETFMTS: // Returns a mask 
+		return put_user(AFMT_S16_LE|AFMT_U16_LE|AFMT_S8|AFMT_U8, (int *)arg);
+
+	case SNDCTL_DSP_SETFMT: // Selects ONE fmt
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		if (val != AFMT_QUERY) {
+			stop_adc(s);
+			stop_dac(s);
+			s->dma_adc.ready = s->dma_dac.ready = 0;
+			// program format 
+			if (val != AFMT_S16_LE && val != AFMT_U16_LE &&
+			    val != AFMT_S8 && val != AFMT_U8)
+				val = AFMT_U8;
+			s->fmt = val;
+			prog_codec(s);
+		}
+		return put_user(s->fmt, (int *)arg);
+
+	case SNDCTL_DSP_POST:
+		return 0;
+
+	case SNDCTL_DSP_GETTRIGGER:
+		val = 0;
+		if (file->f_mode & s->ena & FMODE_READ)
+			val |= PCM_ENABLE_INPUT;
+		if (file->f_mode & s->ena & FMODE_WRITE)
+			val |= PCM_ENABLE_OUTPUT;
+		return put_user(val, (int *)arg);
+
+	case SNDCTL_DSP_SETTRIGGER:
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		if (file->f_mode & FMODE_READ) {
+			if (val & PCM_ENABLE_INPUT) {
+				if (!s->dma_adc.ready && (ret = prog_dmabuf_adc(s)))
+					return ret;
+				start_adc(s);
+			} else
+				stop_adc(s);
+		}
+		if (file->f_mode & FMODE_WRITE) {
+			if (val & PCM_ENABLE_OUTPUT) {
+				if (!s->dma_dac.ready && (ret = prog_dmabuf_dac(s)))
+					return ret;
+				start_dac(s);
+			} else
+				stop_dac(s);
+		}
+		return 0;
+
+	case SNDCTL_DSP_GETOSPACE:
+		if (!(file->f_mode & FMODE_WRITE))
+			return -EINVAL;
+		if (!(s->ena & FMODE_WRITE) && (val = prog_dmabuf_dac(s)) != 0)
+			return val;
+		spin_lock_irqsave(&s->lock, flags);
+		cs4281_update_ptr(s);
+		abinfo.fragsize = s->dma_dac.fragsize;
+		abinfo.bytes = s->dma_dac.dmasize - s->dma_dac.count;
+		abinfo.fragstotal = s->dma_dac.numfrag;
+		abinfo.fragments = abinfo.bytes >> s->dma_dac.fragshift;  
+		spin_unlock_irqrestore(&s->lock, flags);
+		return copy_to_user((void *)arg, &abinfo, sizeof(abinfo)) ? -EFAULT : 0;
+
+	case SNDCTL_DSP_GETISPACE:
+		if (!(file->f_mode & FMODE_READ))
+			return -EINVAL;
+		if (!(s->ena & FMODE_READ) && (val = prog_dmabuf_adc(s)) != 0)
+			return val;
+		spin_lock_irqsave(&s->lock, flags);
+		cs4281_update_ptr(s);
+		abinfo.fragsize = s->dma_adc.fragsize;
+		abinfo.bytes = s->dma_adc.count;
+		abinfo.fragstotal = s->dma_adc.numfrag;
+		abinfo.fragments = abinfo.bytes >> s->dma_adc.fragshift;
+		spin_unlock_irqrestore(&s->lock, flags);
+		return copy_to_user((void *)arg, &abinfo, sizeof(abinfo)) ? -EFAULT : 0;
+
+	case SNDCTL_DSP_NONBLOCK:
+		file->f_flags |= O_NONBLOCK;
+		return 0;
+
+	case SNDCTL_DSP_GETODELAY:
+		if (!(file->f_mode & FMODE_WRITE))
+			return -EINVAL;
+		spin_lock_irqsave(&s->lock, flags);
+		cs4281_update_ptr(s);
+		val = s->dma_dac.count;
+		spin_unlock_irqrestore(&s->lock, flags);
+		return put_user(val, (int *)arg);
+
+	case SNDCTL_DSP_GETIPTR:
+		if (!(file->f_mode & FMODE_READ))
+			return -EINVAL;
+		spin_lock_irqsave(&s->lock, flags);
+		cs4281_update_ptr(s);
+		cinfo.bytes = s->dma_adc.total_bytes;
+		cinfo.blocks = s->dma_adc.count >> s->dma_adc.fragshift;
+		cinfo.ptr = s->dma_adc.hwptr;
+		if (s->dma_adc.mapped)
+			s->dma_adc.count &= s->dma_adc.fragsize-1;
+		spin_unlock_irqrestore(&s->lock, flags);
+		return copy_to_user((void *)arg, &cinfo, sizeof(cinfo));
+
+	case SNDCTL_DSP_GETOPTR:
+		if (!(file->f_mode & FMODE_WRITE))
+			return -EINVAL;
+		spin_lock_irqsave(&s->lock, flags);
+		cs4281_update_ptr(s);
+		cinfo.bytes = s->dma_dac.total_bytes;
+		if (s->dma_dac.mapped)
+		{
+			cinfo.blocks = (cinfo.bytes >> s->dma_dac.fragshift) 
+						- s->dma_adc.blocks;
+			s->dma_dac.blocks = cinfo.bytes >> s->dma_dac.fragshift;
+		}
+		else
+		{
+			cinfo.blocks = s->dma_dac.count >> s->dma_dac.fragshift;
+		}
+		cinfo.ptr = s->dma_dac.hwptr;
+		if (s->dma_dac.mapped)
+			s->dma_dac.count &= s->dma_dac.fragsize-1;
+		spin_unlock_irqrestore(&s->lock, flags);
+		return copy_to_user((void *)arg, &cinfo, sizeof(cinfo));
+
+	case SNDCTL_DSP_GETBLKSIZE:
+		if (file->f_mode & FMODE_WRITE) {
+			if ((val = prog_dmabuf_dac(s)))
+				return val;
+			return put_user(s->dma_dac.fragsize, (int *)arg);
+		}
+		if ((val = prog_dmabuf_adc(s)))
+			return val;
+		return put_user(s->dma_adc.fragsize, (int *)arg);
+
+	case SNDCTL_DSP_SETFRAGMENT:
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		return 0;              // Say OK, but do nothing.
+
+	case SNDCTL_DSP_SUBDIVIDE:
+		if ((file->f_mode & FMODE_READ && s->dma_adc.subdivision) ||
+		    (file->f_mode & FMODE_WRITE && s->dma_dac.subdivision))
+			return -EINVAL;
+		if (get_user(val, (int *)arg))
+			return -EFAULT;
+		if (val != 1 && val != 2 && val != 4)
+			return -EINVAL;
+		if (file->f_mode & FMODE_READ)
+			s->dma_adc.subdivision = val;
+		if (file->f_mode & FMODE_WRITE)
+			s->dma_dac.subdivision = val;
+		return 0;
+
+	case SOUND_PCM_READ_RATE:
+		return put_user(s->rate, (int *)arg);
+
+	case SOUND_PCM_READ_CHANNELS:
+		return put_user(s->channels, (int *)arg);
+
+	case SOUND_PCM_READ_BITS:
+		return put_user((s->fmt & (AFMT_S8|AFMT_U8)) ? 8 : 16, (int *)arg);
+
+	case SOUND_PCM_WRITE_FILTER:
+	case SNDCTL_DSP_SETSYNCRO:
+	case SOUND_PCM_READ_FILTER:
+		return -EINVAL;
+
+	}
+	return mixer_ioctl(s, cmd, arg);
+}
+
+
+static int cs4281_release(struct inode *inode, struct file *file)
+{
+	struct cs4281_state *s = (struct cs4281_state *)file->private_data;
+
+	CS_DBGOUT(CS_FUNCTION | CS_OPEN, 2, 
+		printk(KERN_INFO "cs4281: cs4281_release(): inode=0x%.8x file=0x%.8x\n",
+			(unsigned)inode,(unsigned)file) );
+
+	VALIDATE_STATE(s);
+
+	if (file->f_mode & FMODE_WRITE)
+		drain_dac(s, file->f_flags & O_NONBLOCK);
+	down(&s->open_sem);
+	if (file->f_mode & FMODE_WRITE) {
+		stop_dac(s);
+		dealloc_dmabuf(s,&s->dma_dac);
+	}
+	if (file->f_mode & FMODE_READ) {
+		stop_adc(s);
+		dealloc_dmabuf(s,&s->dma_adc);
+	}
+	s->open_mode &= ~(FMODE_READ | FMODE_WRITE);
+	up(&s->open_sem);
+	wake_up(&s->open_wait);
+	MOD_DEC_USE_COUNT;
+	return 0;
+}
+
+static int cs4281_open(struct inode *inode, struct file *file)
+{
+	int minor = MINOR(inode->i_rdev);
+	struct cs4281_state *s = devs;
+
+	CS_DBGOUT(CS_FUNCTION | CS_OPEN, 2, 
+		printk(KERN_INFO "cs4281: cs4281_open(): inode=0x%.8x file=0x%.8x\n",
+			(unsigned)inode,(unsigned)file) );
+	while (s && ((s->dev_audio ^ minor) & ~0xf))
+		s = s->next;
+	if (!s)
+	{
+		CS_DBGOUT(CS_FUNCTION | CS_OPEN, 2, printk(KERN_INFO 
+			"cs4281: cs4281_open(): ERROR unable to find audio state struct\n") );
+		return -ENODEV;
+	}
+	VALIDATE_STATE(s);
+	file->private_data = s;
+	
+		// wait for device to become free 
+	down(&s->open_sem);
+	while (s->open_mode & (FMODE_READ | FMODE_WRITE)) {
+		if (file->f_flags & O_NONBLOCK) {
+			up(&s->open_sem);
+			return -EBUSY;
+		}
+		up(&s->open_sem);
+		interruptible_sleep_on(&s->open_wait);
+		if (signal_pending(current))
+			return -ERESTARTSYS;
+		down(&s->open_sem);
+	}
+	s->fmt = AFMT_U8;
+	s->channels = 1;
+	s->rate = 8000;
+	s->clkdiv = 96 | 0x80;
+	s->ena = s->endofbuffer = 0;
+	s->dma_adc.ossfragshift = s->dma_adc.ossmaxfrags = s->dma_adc.subdivision = 0;
+	s->dma_dac.ossfragshift = s->dma_dac.ossmaxfrags = s->dma_dac.subdivision = 0;
+	s->open_mode |= file->f_mode & (FMODE_READ | FMODE_WRITE);
+	up(&s->open_sem);
+	MOD_INC_USE_COUNT;
+
+	if (prog_dmabuf_dac(s) || prog_dmabuf_adc(s)) {
+		
+	     printk(KERN_ERR "cs4281: Program dmabufs failed.\n");
+	     cs4281_release(inode, file);
+		
+	     return -ENOMEM;
+	}
+	prog_codec(s);
+	CS_DBGOUT(CS_INIT | CS_FUNCTION | CS_OPEN, 2, 
+		printk(KERN_INFO "cs4281: cs4281_open()- 0\n") );
+	return 0;
+}
+
+
+// ******************************************************************************************
+//   Wave (audio) file operations struct.
+// ******************************************************************************************
+static /*const*/ struct file_operations cs4281_audio_fops = {
+	llseek: 	cs4281_llseek,
+	read:		cs4281_read,
+	write:		cs4281_write,
+	poll:		cs4281_poll,
+	ioctl:		cs4281_ioctl,
+	mmap:		cs4281_mmap,
+	open:		cs4281_open,
+	release:	cs4281_release,
+};
+
+// --------------------------------------------------------------------- 
+
+// hold spinlock for the following! 
+static void cs4281_handle_midi(struct cs4281_state *s)
+{
+	unsigned char ch;
+	int wake;
+	unsigned temp1;
+
+	wake = 0;
+	while (!(readl(s->pBA0+ BA0_MIDSR) & 0x80)) {
+		ch = readl(s->pBA0+BA0_MIDRP);
+		if (s->midi.icnt < MIDIINBUF) {
+			s->midi.ibuf[s->midi.iwr] = ch;
+			s->midi.iwr = (s->midi.iwr + 1) % MIDIINBUF;
+			s->midi.icnt++;
+		}
+		wake = 1;
+	}
+	if (wake)
+		wake_up(&s->midi.iwait);
+	wake = 0;
+	while (!(readl(s->pBA0+ BA0_MIDSR) & 0x40) && s->midi.ocnt > 0) {
+		temp1 = ( s->midi.obuf[s->midi.ord] ) & 0x000000ff;
+		writel(temp1, s->pBA0+BA0_MIDWP);
+		s->midi.ord = (s->midi.ord + 1) % MIDIOUTBUF;
+		s->midi.ocnt--;
+		if (s->midi.ocnt < MIDIOUTBUF-16)
+			wake = 1;
+	}
+	if (wake)
+		wake_up(&s->midi.owait);
+}
+
+
+
+static void cs4281_interrupt(int irq, void *dev_id, struct pt_regs *regs)
+{
+	struct cs4281_state *s = (struct cs4281_state *)dev_id;
+	unsigned int temp1;
+
+	// fastpath out, to ease interrupt sharing 
+	temp1 = readl(s->pBA0+BA0_HISR);                          // Get Int Status reg.
+
+	CS_DBGOUT(CS_INTERRUPT, 6, printk(KERN_INFO 
+		"cs4281: cs4281_interrupt() BA0_HISR=0x%.8x\n",temp1) );
+
+	if (!(temp1 & (HISR_DMA0 | HISR_DMA1 | HISR_MIDI))) {     // If not DMA or MIDI int,
+		writel(HICR_IEV| HICR_CHGM, s->pBA0+BA0_HICR);    //  reenable interrupts
+		CS_DBGOUT(CS_INTERRUPT, 4, printk(KERN_INFO 
+			"cs4281: cs4281_interrupt(): returning not cs4281 interrupt.\n") );
+		return;                                           //   and return.
+	}
+	
+	if(temp1 & HISR_DMA0)                      // If play interrupt,
+		readl(s->pBA0+BA0_HDSR0);              //   clear the source.
+
+	if(temp1 & HISR_DMA1)                      // Same for play.
+		readl(s->pBA0+BA0_HDSR1);        
+	writel(HICR_IEV| HICR_CHGM, s->pBA0+BA0_HICR);  // Local EOI
+	
+	spin_lock(&s->lock);
+	//
+	// ok, at this point we assume that the fifos have been filled
+	// with silence and so we now turn off the DMA engine.
+	// if FMODE_WRITE is set that means that some thread
+	// attempted to start_dac, which probably means that an open
+	// occurred, so do not stop the dac in this case.
+	//
+	if(s->endofbuffer && !(s->ena & FMODE_WRITE))
+	{
+		CS_DBGOUT(CS_INTERRUPT, 2, printk(KERN_INFO 
+			"cs4281: cs4281_interrupt() stopping play DMA\n") );
+		writel(temp1|DCRn_MSK, s->pBA0+BA0_DCR0);    // Stop Play DMA
+		s->endofbuffer = 0;
+	}
+	else
+	{
+		cs4281_update_ptr(s);
+	}
+	cs4281_handle_midi(s);
+	spin_unlock(&s->lock);
+}
+
+// **************************************************************************
+
+static void cs4281_midi_timer(unsigned long data)
+{
+	struct cs4281_state *s = (struct cs4281_state *)data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&s->lock, flags);
+	cs4281_handle_midi(s);
+	spin_unlock_irqrestore(&s->lock, flags);
+	s->midi.timer.expires = jiffies+1;
+	add_timer(&s->midi.timer);
+}
+
+
+// --------------------------------------------------------------------- 
+
+static ssize_t cs4281_midi_read(struct file *file, char *buffer, size_t count, loff_t *ppos)
+{
+	struct cs4281_state *s = (struct cs4281_state *)file->private_data;
+	ssize_t ret;
+	unsigned long flags;
+	unsigned ptr;
+	int cnt;
+
+	VALIDATE_STATE(s);
+	if (ppos != &file->f_pos)
+		return -ESPIPE;
+	if (!access_ok(VERIFY_WRITE, buffer, count))
+		return -EFAULT;
+	ret = 0;
+	while (count > 0) {
+		spin_lock_irqsave(&s->lock, flags);
+		ptr = s->midi.ird;
+		cnt = MIDIINBUF - ptr;
+		if (s->midi.icnt < cnt)
+			cnt = s->midi.icnt;
+		spin_unlock_irqrestore(&s->lock, flags);
+		if (cnt > count)
+			cnt = count;
+		if (cnt <= 0) {
+			if (file->f_flags & O_NONBLOCK)
+				return ret ? ret : -EAGAIN;
+			interruptible_sleep_on(&s->midi.iwait);
+			if (signal_pending(current))
+				return ret ? ret : -ERESTARTSYS;
+			continue;
+		}
+		if (copy_to_user(buffer, s->midi.ibuf + ptr, cnt))
+			return ret ? ret : -EFAULT;
+		ptr = (ptr + cnt) % MIDIINBUF;
+		spin_lock_irqsave(&s->lock, flags);
+		s->midi.ird = ptr;
+		s->midi.icnt -= cnt;
+		spin_unlock_irqrestore(&s->lock, flags);
+		count -= cnt;
+		buffer += cnt;
+		ret += cnt;
+	}
+	return ret;
+}
+
+
+static ssize_t cs4281_midi_write(struct file *file, const char *buffer, size_t count, loff_t *ppos)
+{
+	struct cs4281_state *s = (struct cs4281_state *)file->private_data;
+	ssize_t ret;
+	unsigned long flags;
+	unsigned ptr;
+	int cnt;
+
+	VALIDATE_STATE(s);
+	if (ppos != &file->f_pos)
+		return -ESPIPE;
+	if (!access_ok(VERIFY_READ, buffer, count))
+		return -EFAULT;
+	ret = 0;
+	while (count > 0) {
+		spin_lock_irqsave(&s->lock, flags);
+		ptr = s->midi.owr;
+		cnt = MIDIOUTBUF - ptr;
+		if (s->midi.ocnt + cnt > MIDIOUTBUF)
+			cnt = MIDIOUTBUF - s->midi.ocnt;
+		if (cnt <= 0)
+			cs4281_handle_midi(s);
+		spin_unlock_irqrestore(&s->lock, flags);
+		if (cnt > count)
+			cnt = count;
+		if (cnt <= 0) {
+			if (file->f_flags & O_NONBLOCK)
+				return ret ? ret : -EAGAIN;
+			interruptible_sleep_on(&s->midi.owait);
+			if (signal_pending(current))
+				return ret ? ret : -ERESTARTSYS;
+			continue;
+		}
+		if (copy_from_user(s->midi.obuf + ptr, buffer, cnt))
+			return ret ? ret : -EFAULT;
+		ptr = (ptr + cnt) % MIDIOUTBUF;
+		spin_lock_irqsave(&s->lock, flags);
+		s->midi.owr = ptr;
+		s->midi.ocnt += cnt;
+		spin_unlock_irqrestore(&s->lock, flags);
+		count -= cnt;
+		buffer += cnt;
+		ret += cnt;
+		spin_lock_irqsave(&s->lock, flags);
+		cs4281_handle_midi(s);
+		spin_unlock_irqrestore(&s->lock, flags);
+	}
+	return ret;
+}
+
+
+static unsigned int cs4281_midi_poll(struct file *file, struct poll_table_struct *wait)
+{
+	struct cs4281_state *s = (struct cs4281_state *)file->private_data;
+	unsigned long flags;
+	unsigned int mask = 0;
+
+	VALIDATE_STATE(s);
+	if (file->f_flags & FMODE_WRITE)
+		poll_wait(file, &s->midi.owait, wait);
+	if (file->f_flags & FMODE_READ)
+		poll_wait(file, &s->midi.iwait, wait);
+	spin_lock_irqsave(&s->lock, flags);
+	if (file->f_flags & FMODE_READ) {
+		if (s->midi.icnt > 0)
+			mask |= POLLIN | POLLRDNORM;
+	}
+	if (file->f_flags & FMODE_WRITE) {
+		if (s->midi.ocnt < MIDIOUTBUF)
+			mask |= POLLOUT | POLLWRNORM;
+	}
+	spin_unlock_irqrestore(&s->lock, flags);
+	return mask;
+}
+
+
+static int cs4281_midi_open(struct inode *inode, struct file *file)
+{
+	int minor = MINOR(inode->i_rdev);
+	struct cs4281_state *s = devs;
+	unsigned long flags,temp1;
+	while (s && s->dev_midi != minor)
+		s = s->next;
+	if (!s)
+		return -ENODEV;
+	VALIDATE_STATE(s);
+	file->private_data = s;
+	// wait for device to become free 
+	down(&s->open_sem);
+	while (s->open_mode & (file->f_mode << FMODE_MIDI_SHIFT)) {
+		if (file->f_flags & O_NONBLOCK) {
+			up(&s->open_sem);
+			return -EBUSY;
+		}
+		up(&s->open_sem);
+		interruptible_sleep_on(&s->open_wait);
+		if (signal_pending(current))
+			return -ERESTARTSYS;
+		down(&s->open_sem);
+	}
+	spin_lock_irqsave(&s->lock, flags);
+	if (!(s->open_mode & (FMODE_MIDI_READ | FMODE_MIDI_WRITE))) {
+		s->midi.ird = s->midi.iwr = s->midi.icnt = 0;
+		s->midi.ord = s->midi.owr = s->midi.ocnt = 0;
+		writel(1, s->pBA0+BA0_MIDCR);   // Reset the interface.
+		writel(0, s->pBA0+BA0_MIDCR);   // Return to normal mode.
+		s->midi.ird = s->midi.iwr = s->midi.icnt = 0;
+		writel(0x0000000f, s->pBA0+BA0_MIDCR);                // Enable transmit, record, ints.
+		temp1 = readl(s->pBA0+BA0_HIMR);
+		writel(temp1 & 0xffbfffff, s->pBA0+BA0_HIMR);         // Enable midi int. recognition.
+		writel(HICR_IEV | HICR_CHGM, s->pBA0+BA0_HICR);       // Enable interrupts
+		init_timer(&s->midi.timer);
+		s->midi.timer.expires = jiffies+1;
+		s->midi.timer.data = (unsigned long)s;
+		s->midi.timer.function = cs4281_midi_timer;
+		add_timer(&s->midi.timer);
+	}
+	if (file->f_mode & FMODE_READ) {
+		s->midi.ird = s->midi.iwr = s->midi.icnt = 0;
+	}
+	if (file->f_mode & FMODE_WRITE) {
+		s->midi.ord = s->midi.owr = s->midi.ocnt = 0;
+	}
+	spin_unlock_irqrestore(&s->lock, flags);
+	s->open_mode |= (file->f_mode << FMODE_MIDI_SHIFT) & (FMODE_MIDI_READ | FMODE_MIDI_WRITE);
+	up(&s->open_sem);
+	MOD_INC_USE_COUNT;
+	return 0;
+}
+
+
+static int cs4281_midi_release(struct inode *inode, struct file *file)
+{
+	struct cs4281_state *s = (struct cs4281_state *)file->private_data;
+	DECLARE_WAITQUEUE(wait, current);
+	unsigned long flags;
+	unsigned count, tmo;
+
+	VALIDATE_STATE(s);
+
+	if (file->f_mode & FMODE_WRITE) {
+		current->state = TASK_INTERRUPTIBLE;
+		add_wait_queue(&s->midi.owait, &wait);
+		for (;;) {
+			spin_lock_irqsave(&s->lock, flags);
+			count = s->midi.ocnt;
+			spin_unlock_irqrestore(&s->lock, flags);
+			if (count <= 0)
+				break;
+			if (signal_pending(current))
+				break;
+			if (file->f_flags & O_NONBLOCK) {
+				remove_wait_queue(&s->midi.owait, &wait);
+				current->state = TASK_RUNNING;
+				return -EBUSY;
+			}
+			tmo = (count * HZ) / 3100;
+			if (!schedule_timeout(tmo ? : 1) && tmo)
+				printk(KERN_DEBUG "cs4281: midi timed out??\n");
+		}
+		remove_wait_queue(&s->midi.owait, &wait);
+		current->state = TASK_RUNNING;
+	}
+	down(&s->open_sem);
+	s->open_mode &= (~(file->f_mode << FMODE_MIDI_SHIFT)) & (FMODE_MIDI_READ|FMODE_MIDI_WRITE);
+	spin_lock_irqsave(&s->lock, flags);
+	if (!(s->open_mode & (FMODE_MIDI_READ | FMODE_MIDI_WRITE))) {
+		writel(0, s->pBA0+BA0_MIDCR);    // Disable Midi interrupts.  
+		del_timer(&s->midi.timer);
+	}
+	spin_unlock_irqrestore(&s->lock, flags);
+	up(&s->open_sem);
+	wake_up(&s->open_wait);
+	MOD_DEC_USE_COUNT;
+	return 0;
+}
+
+// ******************************************************************************************
+//   Midi file operations struct.
+// ******************************************************************************************
+static /*const*/ struct file_operations cs4281_midi_fops = {
+	llseek:		cs4281_llseek,
+	read:		cs4281_midi_read,
+	write:		cs4281_midi_write,
+	poll:		cs4281_midi_poll,
+	open:		cs4281_midi_open,
+	release:	cs4281_midi_release,
+};
+
+
+// --------------------------------------------------------------------- 
+
+// maximum number of devices 
+#define NR_DEVICE 8          // Only eight devices supported currently.
+
+// --------------------------------------------------------------------- 
+
+static struct initvol {
+	int mixch;
+	int vol;
+} initvol[] __initdata = {
+	{ SOUND_MIXER_WRITE_VOLUME, 0x4040 },
+	{ SOUND_MIXER_WRITE_PCM, 0x4040 },
+	{ SOUND_MIXER_WRITE_SYNTH, 0x4040 },
+	{ SOUND_MIXER_WRITE_CD, 0x4040 },
+	{ SOUND_MIXER_WRITE_LINE, 0x4040 },
+	{ SOUND_MIXER_WRITE_LINE1, 0x4040 },
+	{ SOUND_MIXER_WRITE_RECLEV, 0x0000 },
+	{ SOUND_MIXER_WRITE_SPEAKER, 0x4040 },
+	{ SOUND_MIXER_WRITE_MIC, 0x0000 }
+};
+
+
+static int __devinit cs4281_probe(struct pci_dev *pcidev, const struct pci_device_id *pciid)
+{
+	struct cs4281_state *s;
+	dma_addr_t dma_mask;
+	mm_segment_t fs;
+	int i, val, index = 0;
+	unsigned int temp1, temp2;
+ 
+	CS_DBGOUT(CS_INIT, 2, printk(KERN_INFO "cs4281: probe()+\n") );
+
+	if (!RSRCISMEMORYREGION(pcidev, 0) ||
+	    !RSRCISMEMORYREGION(pcidev, 1))
+	{
+		CS_DBGOUT(CS_ERROR, 1,
+			printk(KERN_ERR "cs4281: probe()- Memory region not assigned\n") );
+		return -1;
+	}
+	if (pcidev->irq == 0) {
+		CS_DBGOUT(CS_ERROR, 1,
+			printk(KERN_ERR "cs4281: probe() IRQ not assigned\n") );
+		return -1;
+	} 
+	if (!pci_dma_supported(pcidev, 0xffffffff)) {
+		CS_DBGOUT(CS_ERROR, 1, printk(KERN_ERR 
+		    "cs4281: probe() architecture does not support 32bit PCI busmaster DMA\n") );
+		return -1;
+	} 
+	dma_mask = 0xffffffff; /* this enables playback and recording */
+	if (!(s = kmalloc(sizeof(struct cs4281_state), GFP_KERNEL))) {
+		CS_DBGOUT(CS_ERROR, 1, printk(KERN_ERR 
+			"cs4281: probe() no memory for state struct.\n") );
+		return -1;
+	}
+	memset(s, 0, sizeof(struct cs4281_state));
+	init_waitqueue_head(&s->dma_adc.wait);
+	init_waitqueue_head(&s->dma_dac.wait);
+	init_waitqueue_head(&s->open_wait);
+	init_waitqueue_head(&s->midi.iwait);
+	init_waitqueue_head(&s->midi.owait);
+	init_MUTEX(&s->open_sem);
+	spin_lock_init(&s->lock);
+	s->pBA0phys = RSRCADDRESS(pcidev, 0);
+	s->pBA1phys = RSRCADDRESS(pcidev, 1);
+	s->pBA0 = ioremap_nocache(s->pBA0phys, 4096);   // Convert phys 
+	s->pBA1 = ioremap_nocache(s->pBA1phys, 65536);  //  to linear. 
+	temp1 = readl(s->pBA0+ BA0_PCICFG00);
+	temp2 = readl(s->pBA0+ BA0_PCICFG04);
+
+	CS_DBGOUT(CS_INIT, 2, 
+	    printk(KERN_INFO "cs4281: probe() BA0=0x%.8x BA1=0x%.8x pBA0=0x%.8x pBA1=0x%.8x \n",
+		(unsigned)temp1,(unsigned)temp2,(unsigned)s->pBA0,(unsigned)s->pBA1) );
+
+	CS_DBGOUT(CS_INIT, 2, 
+	    printk(KERN_INFO "cs4281: probe() pBA0phys=0x%.8x pBA1phys=0x%.8x\n",
+		(unsigned)s->pBA0phys,(unsigned)s->pBA1phys) );
+
+	temp1 = cs4281_hw_init(s);
+	if(temp1){
+		CS_DBGOUT(CS_ERROR | CS_INIT, 1, 
+		    printk(KERN_ERR "cs4281: cs4281_hw_init() failed. Skipping part.\n") );
+		return -1;
+	}	
+	s->magic = CS4281_MAGIC;
+	s->pcidev = pcidev;
+	s->irq = pcidev->irq;
+	if (pci_enable_device(pcidev))
+	{
+		CS_DBGOUT(CS_INIT | CS_ERROR, 1, 
+			printk(KERN_ERR "cs4281: pci_enable_device() failed\n") );
+		goto err_irq;
+	}
+	if(request_irq(s->irq, cs4281_interrupt, SA_SHIRQ, "Crystal CS4281", s)){
+		CS_DBGOUT(CS_INIT | CS_ERROR, 1, 
+			printk(KERN_ERR "cs4281: irq %u in use\n", s->irq) );
+		goto err_irq;
+	}
+	if ((s->dev_audio = register_sound_dsp(&cs4281_audio_fops, -1)) < 0)
+	{
+		CS_DBGOUT(CS_INIT | CS_ERROR, 1, 
+			printk(KERN_ERR "cs4281: probe() register_sound_dsp() failed.\n") );
+		goto err_dev1;
+	}
+	if ((s->dev_mixer = register_sound_mixer(&cs4281_mixer_fops, -1)) < 0)
+	{
+		CS_DBGOUT(CS_INIT | CS_ERROR, 1, 
+			printk(KERN_ERR "cs4281: probe() register_sound_mixer() failed.\n") );
+		goto err_dev2;
+	}
+	if ((s->dev_midi = register_sound_midi(&cs4281_midi_fops, -1)) < 0)
+	{
+		CS_DBGOUT(CS_INIT | CS_ERROR, 1, 
+			printk(KERN_ERR "cs4281: probe() register_sound_midi() failed.\n") );
+		goto err_dev3;
+	}
+			    
+	pci_set_master(pcidev);           // enable bus mastering 
+
+	fs = get_fs();
+	set_fs(KERNEL_DS);
+	val = SOUND_MASK_LINE;
+	mixer_ioctl(s, SOUND_MIXER_WRITE_RECSRC, (unsigned long)&val);
+	for (i = 0; i < sizeof(initvol)/sizeof(initvol[0]); i++) {
+		val = initvol[i].vol;
+		mixer_ioctl(s, initvol[i].mixch, (unsigned long)&val);
+	}
+	val = 1; // enable mic preamp 
+	mixer_ioctl(s, SOUND_MIXER_PRIVATE1, (unsigned long)&val);
+	set_fs(fs);
+	
+	// queue it for later freeing 
+	s->next = devs;
+	pcidev->driver_data = s;
+	pcidev->dma_mask = dma_mask;
+	devs = s;
+	index++;
+	return 0;
+
+err_dev3:
+	unregister_sound_mixer(s->dev_mixer);
+err_dev2:
+	unregister_sound_dsp(s->dev_audio);
+err_dev1:
+	free_irq(s->irq, s);
+err_irq:
+	kfree(s);
+
+	if (!devs)
+	{
+		CS_DBGOUT(CS_INIT | CS_ERROR, 1,
+			printk(KERN_INFO "cs4281: probe()- no device allocated\n") );
+		return -ENODEV;
+	}
+	CS_DBGOUT(CS_INIT | CS_FUNCTION, 2,
+		printk(KERN_INFO "cs4281: probe()- device allocated successfully\n") );
+	return 0;
+} // probe_cs4281
+
+
+// --------------------------------------------------------------------- 
+
+static void __devinit cs4281_remove(struct pci_dev *dev)
+{
+	struct cs4281_state *s = (struct cs4281_state *)dev->driver_data;
+	// stop DMA controller 
+	synchronize_irq();
+	free_irq(s->irq, s);
+	unregister_sound_dsp(s->dev_audio);
+	unregister_sound_mixer(s->dev_mixer);
+	unregister_sound_midi(s->dev_midi);
+	kfree(s);
+	dev->driver_data = NULL;	
+	CS_DBGOUT(CS_INIT | CS_FUNCTION, 2, 
+		printk(KERN_INFO "cs4281: cs4281_remove(): remove successful\n") );
+}
+
+static struct pci_device_id id_table[] __devinitdata = {
+	{ PCI_VENDOR_ID_CIRRUS, PCI_DEVICE_ID_CRYSTAL_CS4281, PCI_ANY_ID, PCI_ANY_ID, 0, 0 },
+	{ 0, }
+};
+
+MODULE_DEVICE_TABLE(pci, id_table);
+
+static struct pci_driver cs4281_driver = {
+	name: "cs4281",
+	id_table: id_table,
+	probe: cs4281_probe,
+	remove: cs4281_remove
+};
+
+static int __init init_cs4281(void)
+{
+	
+	CS_DBGOUT(CS_INIT | CS_FUNCTION, 2, printk(KERN_INFO "cs4281: init_cs4281()+ \n") );
+	if (!pci_present())   /* No PCI bus in this machine! */
+	{
+		CS_DBGOUT(CS_INIT | CS_FUNCTION, 2, 
+			printk(KERN_INFO "cs4281: init_cs4281()- no pci bus found\n") );
+		return -ENODEV;
+	}
+	printk(KERN_INFO "cs4281: version v%d.%02d.%d time " __TIME__ " " __DATE__ "\n",
+		CS4281_MAJOR_VERSION, CS4281_MINOR_VERSION, CS4281_ARCH);
+	if (!pci_register_driver(&cs4281_driver)) {
+		pci_unregister_driver(&cs4281_driver);
+		CS_DBGOUT(CS_INIT | CS_FUNCTION, 2, 
+			printk(KERN_INFO "cs4281: init_cs4281()- unable to register pci device \n") );
+		return -ENODEV;
+	}
+	CS_DBGOUT(CS_INIT | CS_FUNCTION, 2, printk(KERN_INFO "cs4281: init_cs4281()- 0\n") );
+	return 0;
+}
+
+
+// --------------------------------------------------------------------- 
+
+
+MODULE_AUTHOR("gw boynton, wesb@crystal.cirrus.com");
+MODULE_DESCRIPTION("Cirrus Logic CS4281 Driver");
+
+static void __exit cleanup_cs4281(void)
+{
+	pci_unregister_driver(&cs4281_driver);
+	CS_DBGOUT(CS_INIT | CS_FUNCTION, 2, 
+		printk(KERN_INFO "cs4281: cleanup_cs4281() finished\n") );
+}
+
+// --------------------------------------------------------------------- 
+
+module_init(init_cs4281);
+module_exit(cleanup_cs4281);
+

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TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)