i810_audio.c

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/*
 *	Intel i810 and friends ICH driver for Linux
 *	Alan Cox <[e-mail]>
 *
 *  Built from:
 *	Low level code:  Zach Brown (original nonworking i810 OSS driver)
 *			 Jaroslav Kysela <[e-mail]> (working ALSA driver)
 *
 *	Framework: Thomas Sailer <[e-mail]>
 *	Extended by: Zach Brown <[e-mail]>  
 *			and others..
 *
 *  Hardware Provided By:
 *	Analog Devices (A major AC97 codec maker)
 *	Intel Corp  (you've probably heard of them already)
 *
 * AC97 clues and assistance provided by
 *	Analog Devices
 *	Zach 'Fufu' Brown
 *	Jeff Garzik
 *
 *	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.
 *
 *
 *	Intel 810 theory of operation
 *
 *	The chipset provides three DMA channels that talk to an AC97
 *	CODEC (AC97 is a digital/analog mixer standard). At its simplest
 *	you get 48Khz audio with basic volume and mixer controls. At the
 *	best you get rate adaption in the codec. We set the card up so
 *	that we never take completion interrupts but instead keep the card
 *	chasing its tail around a ring buffer. This is needed for mmap
 *	mode audio and happens to work rather well for non-mmap modes too.
 *
 *	The board has one output channel for PCM audio (supported) and
 *	a stereo line in and mono microphone input. Again these are normally
 *	locked to 48Khz only. Right now recording is not finished.
 *
 *	There is no midi support, no synth support. Use timidity. To get
 *	esd working you need to use esd -r 48000 as it won't probe 48KHz
 *	by default. mpg123 can't handle 48Khz only audio so use xmms.
 *
 *	Fix The Sound On Dell
 *
 *	Not everyone uses 48KHz. We know of no way to detect this reliably
 *	and certainly not to get the right data. If your i810 audio sounds
 *	stupid you may need to investigate other speeds. According to Analog
 *	they tend to use a 14.318MHz clock which gives you a base rate of
 *	41194Hz.
 *
 *	This is available via the 'ftsodell=1' option. 
 *
 *	If you need to force a specific rate set the clocking= option
 */
 
#include <linux/module.h>
#include <linux/version.h>
#include <linux/string.h>
#include <linux/ctype.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 <asm/io.h>
#include <asm/dma.h>
#include <linux/init.h>
#include <linux/poll.h>
#include <linux/spinlock.h>
#include <linux/smp_lock.h>
#include <linux/ac97_codec.h>
#include <linux/wrapper.h>
#include <asm/uaccess.h>
#include <asm/hardirq.h>

#ifndef PCI_DEVICE_ID_INTEL_82801
#define PCI_DEVICE_ID_INTEL_82801	0x2415
#endif
#ifndef PCI_DEVICE_ID_INTEL_82901
#define PCI_DEVICE_ID_INTEL_82901	0x2425
#endif
#ifndef PCI_DEVICE_ID_INTEL_ICH2
#define PCI_DEVICE_ID_INTEL_ICH2	0x2445
#endif
#ifndef PCI_DEVICE_ID_INTEL_440MX
#define PCI_DEVICE_ID_INTEL_440MX	0x7195
#endif

static int ftsodell=0;
static unsigned int clocking=48000;


#define ADC_RUNNING	1
#define DAC_RUNNING	2

#define I810_FMT_16BIT	1
#define I810_FMT_STEREO	2
#define I810_FMT_MASK	3

/* the 810's array of pointers to data buffers */

struct sg_item {
#define BUSADDR_MASK	0xFFFFFFFE
	u32 busaddr;	
#define CON_IOC 	0x80000000 /* interrupt on completion */
#define CON_BUFPAD	0x40000000 /* pad underrun with last sample, else 0 */
#define CON_BUFLEN_MASK	0x0000ffff /* buffer length in samples */
	u32 control;
};

/* an instance of the i810 channel */
#define SG_LEN 32
struct i810_channel 
{
	/* these sg guys should probably be allocated
	   seperately as nocache. Must be 8 byte aligned */
	struct sg_item sg[SG_LEN];	/* 32*8 */
	u32 offset;			/* 4 */
	u32 port;			/* 4 */
	u32 used;
	u32 num;
};

/*
 * we have 3 seperate dma engines.  pcm in, pcm out, and mic.
 * each dma engine has controlling registers.  These goofy
 * names are from the datasheet, but make it easy to write
 * code while leafing through it.
 */

#define ENUM_ENGINE(PRE,DIG) 									\
enum {												\
	PRE##_BDBAR =	0x##DIG##0,		/* Buffer Descriptor list Base Address */	\
	PRE##_CIV =	0x##DIG##4,		/* Current Index Value */			\
	PRE##_LVI =	0x##DIG##5,		/* Last Valid Index */				\
	PRE##_SR =	0x##DIG##6,		/* Status Register */				\
	PRE##_PICB =	0x##DIG##8,		/* Position In Current Buffer */		\
	PRE##_PIV =	0x##DIG##a,		/* Prefetched Index Value */			\
	PRE##_CR =	0x##DIG##b		/* Control Register */				\
}

ENUM_ENGINE(OFF,0);	/* Offsets */
ENUM_ENGINE(PI,0);	/* PCM In */
ENUM_ENGINE(PO,1);	/* PCM Out */
ENUM_ENGINE(MC,2);	/* Mic In */

enum {
	GLOB_CNT =	0x2c,			/* Global Control */
	GLOB_STA = 	0x30,			/* Global Status */
	CAS	 = 	0x34			/* Codec Write Semaphore Register */
};

/* interrupts for a dma engine */
#define DMA_INT_FIFO		(1<<4)  /* fifo under/over flow */
#define DMA_INT_COMPLETE	(1<<3)  /* buffer read/write complete and ioc set */
#define DMA_INT_LVI		(1<<2)  /* last valid done */
#define DMA_INT_CELV		(1<<1)  /* last valid is current */
#define DMA_INT_MASK (DMA_INT_FIFO|DMA_INT_COMPLETE|DMA_INT_LVI)

/* interrupts for the whole chip */
#define INT_SEC		(1<<11)
#define INT_PRI		(1<<10)
#define INT_MC		(1<<7)
#define INT_PO		(1<<6)
#define INT_PI		(1<<5)
#define INT_MO		(1<<2)
#define INT_NI		(1<<1)
#define INT_GPI		(1<<0)
#define INT_MASK (INT_SEC|INT_PRI|INT_MC|INT_PO|INT_PI|INT_MO|INT_NI|INT_GPI)


#define DRIVER_VERSION "0.01"

/* magic numbers to protect our data structures */
#define I810_CARD_MAGIC		0x5072696E /* "Prin" */
#define I810_STATE_MAGIC	0x63657373 /* "cess" */
#define I810_DMA_MASK		0xffffffff /* DMA buffer mask for pci_alloc_consist */
#define NR_HW_CH		3

/* maxinum number of AC97 codecs connected, AC97 2.0 defined 4 */
#define NR_AC97		2

static const unsigned sample_size[] = { 1, 2, 2, 4 };
static const unsigned sample_shift[] = { 0, 1, 1, 2 };

enum {
	ICH82801AA = 0,
	ICH82901AB,
	INTEL440MX,
	INTELICH2,
};

static char * card_names[] = {
	"Intel ICH 82801AA",
	"Intel ICH 82901AB",
	"Intel 440MX",
	"Intel ICH2"
};

static struct pci_device_id i810_pci_tbl [] __initdata = {
	{PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801,
	 PCI_ANY_ID, PCI_ANY_ID, 0, 0, ICH82801AA},
	{PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82901,
	 PCI_ANY_ID, PCI_ANY_ID, 0, 0, ICH82901AB},
	{PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_440MX,
	 PCI_ANY_ID, PCI_ANY_ID, 0, 0, INTEL440MX},
	{PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_ICH2,
	 PCI_ANY_ID, PCI_ANY_ID, 0, 0, INTELICH2},
	{0,}
};

MODULE_DEVICE_TABLE (pci, i810_pci_tbl);

/* "software" or virtual channel, an instance of opened /dev/dsp */
struct i810_state {
	unsigned int magic;
	struct i810_card *card;	/* Card info */

	/* single open lock mechanism, only used for recording */
	struct semaphore open_sem;
	wait_queue_head_t open_wait;

	/* file mode */
	mode_t open_mode;

	/* virtual channel number */
	int virt;

	struct dmabuf {
		/* wave sample stuff */
		unsigned int rate;
		unsigned char fmt, enable;

		/* hardware channel */
		struct i810_channel *channel;

		/* OSS buffer management stuff */
		void *rawbuf;
		dma_addr_t dma_handle;
		unsigned buforder;
		unsigned numfrag;
		unsigned fragshift;

		/* our buffer acts like a circular ring */
		unsigned hwptr;		/* where dma last started, updated by update_ptr */
		unsigned swptr;		/* where driver last clear/filled, updated by read/write */
		int count;		/* bytes to be comsumed or been generated by dma machine */
		unsigned total_bytes;	/* total bytes dmaed by hardware */

		unsigned error;		/* number of over/underruns */
		wait_queue_head_t wait;	/* put process on wait queue when no more space in buffer */

		/* redundant, but makes calculations easier */
		unsigned fragsize;
		unsigned dmasize;
		unsigned fragsamples;

		/* OSS stuff */
		unsigned mapped:1;
		unsigned ready:1;
		unsigned endcleared:1;
		unsigned update_flag;
		unsigned ossfragshift;
		int ossmaxfrags;
		unsigned subdivision;
	} dmabuf;
};


struct i810_card {
	struct i810_channel channel[3];
	unsigned int magic;

	/* We keep i810 cards in a linked list */
	struct i810_card *next;

	/* The i810 has a certain amount of cross channel interaction
	   so we use a single per card lock */
	spinlock_t lock;

	/* PCI device stuff */
	struct pci_dev * pci_dev;
	u16 pci_id;

	/* soundcore stuff */
	int dev_audio;

	/* structures for abstraction of hardware facilities, codecs, banks and channels*/
	struct ac97_codec *ac97_codec[NR_AC97];
	struct i810_state *states[NR_HW_CH];

	u16 ac97_features;
	
	/* hardware resources */
	unsigned long iobase;
	unsigned long ac97base;
	u32 irq;
	
	/* Function support */
	struct i810_channel *(*alloc_pcm_channel)(struct i810_card *);
	struct i810_channel *(*alloc_rec_pcm_channel)(struct i810_card *);
	void (*free_pcm_channel)(struct i810_card *, int chan);
};

static struct i810_card *devs = NULL;

static int i810_open_mixdev(struct inode *inode, struct file *file);
static int i810_ioctl_mixdev(struct inode *inode, struct file *file, unsigned int cmd,
				unsigned long arg);
static loff_t i810_llseek(struct file *file, loff_t offset, int origin);

extern __inline__ unsigned ld2(unsigned int x)
{
	unsigned r = 0;
	
	if (x >= 0x10000) {
		x >>= 16;
		r += 16;
	}
	if (x >= 0x100) {
		x >>= 8;
		r += 8;
	}
	if (x >= 0x10) {
		x >>= 4;
		r += 4;
	}
	if (x >= 4) {
		x >>= 2;
		r += 2;
	}
	if (x >= 2)
		r++;
	return r;
}

static u16 i810_ac97_get(struct ac97_codec *dev, u8 reg);
static void i810_ac97_set(struct ac97_codec *dev, u8 reg, u16 data);

static struct i810_channel *i810_alloc_pcm_channel(struct i810_card *card)
{
	if(card->channel[1].used==1)
		return NULL;
	card->channel[1].used=1;
	card->channel[1].offset = 0;
	card->channel[1].port = 0x10;
	card->channel[1].num=1;
	return &card->channel[1];
}

static struct i810_channel *i810_alloc_rec_pcm_channel(struct i810_card *card)
{
	if(card->channel[0].used==1)
		return NULL;
	card->channel[0].used=1;
	card->channel[0].offset = 0;
	card->channel[0].port = 0x00;
	card->channel[1].num=0;
	return &card->channel[0];
}

static void i810_free_pcm_channel(struct i810_card *card, int channel)
{
	card->channel[channel].used=0;
}

/* set playback sample rate */
static unsigned int i810_set_dac_rate(struct i810_state * state, unsigned int rate)
{	
	struct dmabuf *dmabuf = &state->dmabuf;
	u32 dacp;
	struct ac97_codec *codec=state->card->ac97_codec[0];
	
	if(!(state->card->ac97_features&0x0001))
	{
		dmabuf->rate = clocking;
		return clocking;
	}
			
	if (rate > 48000)
		rate = 48000;
	if (rate < 8000)
		rate = 8000;
		
	/*
	 *	Adjust for misclocked crap
	 */
	 
	rate = ( rate * clocking)/48000;
	
	/* Analog codecs can go lower via magic registers but others
	   might not */
	   
	if(rate < 8000)
		rate = 8000;

	if(rate != i810_ac97_get(codec, AC97_PCM_FRONT_DAC_RATE))
	{
		/* Power down the DAC */
		dacp=i810_ac97_get(codec, AC97_POWER_CONTROL);
		i810_ac97_set(codec, AC97_POWER_CONTROL, dacp|0x0200);
		/* Load the rate and read the effective rate */
		i810_ac97_set(codec, AC97_PCM_FRONT_DAC_RATE, rate);
		rate=i810_ac97_get(codec, AC97_PCM_FRONT_DAC_RATE);
		/* Power it back up */
		i810_ac97_set(codec, AC97_POWER_CONTROL, dacp);
	}
	rate=(rate * 48000) / clocking;
	dmabuf->rate = rate;
#ifdef DEBUG
	printk("i810_audio: called i810_set_dac_rate : rate = %d\n", rate);
#endif

	return rate;
}

/* set recording sample rate */
static unsigned int i810_set_adc_rate(struct i810_state * state, unsigned int rate)
{
	struct dmabuf *dmabuf = &state->dmabuf;
	u32 dacp;
	struct ac97_codec *codec=state->card->ac97_codec[0];
	
	if(!(state->card->ac97_features&0x0001))
	{
		dmabuf->rate = clocking;
		return clocking;
	}
			
	if (rate > 48000)
		rate = 48000;
	if (rate < 8000)
		rate = 8000;

	/*
	 *	Adjust for misclocked crap
	 */
	 
	rate = ( rate * clocking)/48000;
	
	/* Analog codecs can go lower via magic registers but others
	   might not */
	   
	if(rate < 8000)
		rate = 8000;

	if(rate != i810_ac97_get(codec, AC97_PCM_LR_DAC_RATE))
	{
		/* Power down the ADC */
		dacp=i810_ac97_get(codec, AC97_POWER_CONTROL);
		i810_ac97_set(codec, AC97_POWER_CONTROL, dacp|0x0100);
		/* Load the rate and read the effective rate */
		i810_ac97_set(codec, AC97_PCM_LR_DAC_RATE, rate);
		rate=i810_ac97_get(codec, AC97_PCM_LR_DAC_RATE);
		/* Power it back up */
		i810_ac97_set(codec, AC97_POWER_CONTROL, dacp);
	}
	rate = (rate * 48000) / clocking;
	dmabuf->rate = rate;
#ifdef DEBUG
	printk("i810_audio: called i810_set_adc_rate : rate = %d\n", rate);
#endif
	return rate;
}

/* prepare channel attributes for playback */ 
static void i810_play_setup(struct i810_state *state)
{
//	struct dmabuf *dmabuf = &state->dmabuf;
//	struct i810_channel *channel = dmabuf->channel;
	/* Fixed format. .. */
	//if (dmabuf->fmt & I810_FMT_16BIT)
	//if (dmabuf->fmt & I810_FMT_STEREO)
}

/* prepare channel attributes for recording */
static void i810_rec_setup(struct i810_state *state)