pg.c

是关于linux2.5.1的完全源码

}

#endif

#define	WR(c,r,v)	pi_write_regr(PI,c,r,v)
#define	RR(c,r)		(pi_read_regr(PI,c,r))

#define DRIVE           (0xa0+0x10*PG.drive)

static void pg_sleep( int cs )

{       current->state = TASK_INTERRUPTIBLE;
	schedule_timeout(cs);
}

static int pg_wait( int unit, int go, int stop, int tmo, char * msg )

{       int j, r, e, s, p;

	PG.status = 0;

	j = 0;
	while ((((r=RR(1,6))&go)||(stop&&(!(r&stop))))&&(time_before(jiffies,tmo))) {
		if (j++ < PG_SPIN) udelay(PG_SPIN_DEL);
		else pg_sleep(1);
	}

	if ((r&(STAT_ERR&stop))||time_after_eq(jiffies, tmo)) {
	   s = RR(0,7);
	   e = RR(0,1);
	   p = RR(0,2);
	   if (verbose > 1)
	     printk("%s: %s: stat=0x%x err=0x%x phase=%d%s\n",
		   PG.name,msg,s,e,p,time_after_eq(jiffies, tmo)?" timeout":"");


	   if (time_after_eq(jiffies, tmo)) e |= 0x100;
	   PG.status = (e >> 4) & 0xff;
	   return -1;
	}
	return 0;
}

static int pg_command( int unit, char * cmd, int dlen, int tmo )

{       int k;

	pi_connect(PI);

	WR(0,6,DRIVE);

	if (pg_wait(unit,STAT_BUSY|STAT_DRQ,0,tmo,"before command")) {
		pi_disconnect(PI);
		return -1;
	}

	WR(0,4,dlen % 256);
	WR(0,5,dlen / 256);
	WR(0,7,0xa0);          /* ATAPI packet command */

	if (pg_wait(unit,STAT_BUSY,STAT_DRQ,tmo,"command DRQ")) {
		pi_disconnect(PI);
		return -1;
	}

	if (RR(0,2) != 1) {
	   printk("%s: command phase error\n",PG.name);
	   pi_disconnect(PI);
	   return -1;
	}

	pi_write_block(PI,cmd,12);

	if (verbose > 1) {
		printk("%s: Command sent, dlen=%d packet= ", PG.name,dlen);
		for (k=0;k<12;k++) printk("%02x ",cmd[k]&0xff);
		printk("\n");
	}
	return 0;
}

static int pg_completion( int unit, char * buf, int tmo)

{       int r, d, n, p;

	r = pg_wait(unit,STAT_BUSY,STAT_DRQ|STAT_READY|STAT_ERR,
			tmo,"completion");

	PG.dlen = 0;

	while (RR(0,7)&STAT_DRQ) {
	   d = (RR(0,4)+256*RR(0,5));
	   n = ((d+3)&0xfffc);
	   p = RR(0,2)&3;
	   if (p == 0) pi_write_block(PI,buf,n);
	   if (p == 2) pi_read_block(PI,buf,n);
	   if (verbose > 1) printk("%s: %s %d bytes\n",PG.name,
				    p?"Read":"Write",n);
	   PG.dlen += (1-p)*d;
	   buf += d;
	   r = pg_wait(unit,STAT_BUSY,STAT_DRQ|STAT_READY|STAT_ERR,
			tmo,"completion");
	}

	pi_disconnect(PI); 

	return r;
}

static int pg_reset( int unit )

{	int	i, k, flg;
	int	expect[5] = {1,1,1,0x14,0xeb};

	pi_connect(PI);
	WR(0,6,DRIVE);
	WR(0,7,8);

	pg_sleep(20*HZ/1000);

	k = 0;
	while ((k++ < PG_RESET_TMO) && (RR(1,6)&STAT_BUSY))
		pg_sleep(1);

	flg = 1;
	for(i=0;i<5;i++) flg &= (RR(0,i+1) == expect[i]);

	if (verbose) {
		printk("%s: Reset (%d) signature = ",PG.name,k);
		for (i=0;i<5;i++) printk("%3x",RR(0,i+1));
		if (!flg) printk(" (incorrect)");
		printk("\n");
	}
	
	pi_disconnect(PI);
	return flg-1;	
}

static void xs( char *buf, char *targ, int offs, int len )

{	int	j,k,l;

	j=0; l=0;
	for (k=0;k<len;k++) 
	   if((buf[k+offs]!=0x20)||(buf[k+offs]!=l))
		l=targ[j++]=buf[k+offs];
	if (l==0x20) j--;
	targ[j]=0;
}

static int pg_identify( int unit, int log )

{	int 	s;
	char	*ms[2] = {"master","slave"};
	char	mf[10], id[18];
	char    id_cmd[12] = { ATAPI_IDENTIFY,0,0,0,36,0,0,0,0,0,0,0};
	char	buf[36];

	s = pg_command(unit,id_cmd,36,jiffies+PG_TMO);
	if (s) return -1;
	s = pg_completion(unit,buf,jiffies+PG_TMO);
	if (s) return -1;

	if (log) {
		xs(buf,mf,8,8);
		xs(buf,id,16,16);
		printk("%s: %s %s, %s\n",PG.name,mf,id,ms[PG.drive]);
	}

	return 0;
}

static int pg_probe( int unit )

/*	returns  0, with id set if drive is detected
		-1, if drive detection failed
*/

{	if (PG.drive == -1) {
	   for (PG.drive=0;PG.drive<=1;PG.drive++)
		if (!pg_reset(unit)) return pg_identify(unit,1);
	} else {
	   if (!pg_reset(unit)) return pg_identify(unit,1);
	}
	return -1; 
}

static int pg_detect( void )

{	int	k, unit;

	printk("%s: %s version %s, major %d\n",
		name,name,PG_VERSION,major);

	k = 0;
	if (pg_drive_count == 0) {
	    unit = 0;
	    if (pi_init(PI,1,-1,-1,-1,-1,-1,pg_scratch,
			PI_PG,verbose,PG.name)) {
		if (!pg_probe(unit)) {
			PG.present = 1;
			k++;
		} else pi_release(PI);
	    }

	} else for (unit=0;unit<PG_UNITS;unit++) if (DU[D_PRT])
	    if (pi_init(PI,0,DU[D_PRT],DU[D_MOD],DU[D_UNI],
			DU[D_PRO],DU[D_DLY],pg_scratch,PI_PG,verbose,
			PG.name)) { 
		if (!pg_probe(unit)) {
			PG.present = 1;
			k++;
		} else pi_release(PI);
	    }

	if (k) return 0;

	printk("%s: No ATAPI device detected\n",name);
	return -1;
}

#define DEVICE_NR(dev)	(minor(dev) & 0x7F)

static int pg_open (struct inode *inode, struct file *file)

{       int	unit = DEVICE_NR(inode->i_rdev);

	if ((unit >= PG_UNITS) || (!PG.present)) return -ENODEV;

	if ( test_and_set_bit(0, &PG.access) ) {
		return -EBUSY;
	}

	if (PG.busy) {
		pg_reset(unit);
		PG.busy = 0;
	}

	pg_identify(unit,(verbose>1));


	PG.bufptr = kmalloc(PG_MAX_DATA,GFP_KERNEL);
	if (PG.bufptr == NULL) {
		clear_bit( 0, &PG.access ) ;
		printk("%s: buffer allocation failed\n",PG.name);
		return -ENOMEM;
	}

	return 0;
}

static int pg_release (struct inode *inode, struct file *file)
{
	int	unit = DEVICE_NR(inode->i_rdev);

	if ( unit >= PG_UNITS || !test_bit(0,&PG.access) )
		return -EINVAL;

	clear_bit( 0, &PG.access);

	kfree(PG.bufptr);
	PG.bufptr = NULL;

	return 0;

}

static ssize_t pg_write(struct file * filp, const char * buf, 
			size_t count, loff_t *ppos)

{       struct inode            *ino = filp->f_dentry->d_inode;
	int                     unit = DEVICE_NR(ino->i_rdev);
	struct pg_write_hdr     hdr;
	int                     hs = sizeof(hdr);

	if (PG.busy) return -EBUSY;
	if (count < hs) return -EINVAL;
	
	copy_from_user((char *)&hdr,buf,hs);

	if (hdr.magic != PG_MAGIC) return -EINVAL;
	if (hdr.dlen > PG_MAX_DATA) return -EINVAL;
	if ((count - hs) > PG_MAX_DATA) return -EINVAL;

	if (hdr.func == PG_RESET) {
		if (count != hs) return -EINVAL;
		if (pg_reset(unit)) return -EIO;
		return count;
	}

	if (hdr.func != PG_COMMAND) return -EINVAL;

	PG.start = jiffies;
	PG.timeout = hdr.timeout*HZ + HZ/2 + jiffies;

	if (pg_command(unit,hdr.packet,hdr.dlen,jiffies+PG_TMO)) {
		if (PG.status & 0x10) return -ETIME;
		return -EIO;
	}

	PG.busy = 1;

	copy_from_user(PG.bufptr,buf+hs,count-hs);

	return count;
}

static ssize_t pg_read(struct file * filp, char * buf, 
		       size_t count, loff_t *ppos)

{  	struct inode 		*ino = filp->f_dentry->d_inode;
	int			unit = DEVICE_NR(ino->i_rdev);
	struct pg_read_hdr 	hdr;
	int			hs = sizeof(hdr);
	int			copy;

	if (!PG.busy) return -EINVAL;
	if (count < hs) return -EINVAL;

	PG.busy = 0;

	if (pg_completion(unit,PG.bufptr,PG.timeout))
	  if (PG.status & 0x10) return -ETIME;

	hdr.magic = PG_MAGIC;
	hdr.dlen = PG.dlen;
	copy = 0;

	if (hdr.dlen < 0) {
		hdr.dlen = -1 * hdr.dlen;
		copy = hdr.dlen;
		if (copy > (count - hs)) copy = count - hs;
	}

	hdr.duration = (jiffies - PG.start + HZ/2) / HZ;
	hdr.scsi = PG.status & 0x0f;

	copy_to_user(buf,(char *)&hdr,hs);
	if (copy > 0) copy_to_user(buf+hs,PG.bufptr,copy);
	
	return copy+hs;
}

/* end of pg.c */

MODULE_LICENSE("GPL");