Contributors: 5
Author Tokens Token Proportion Commits Commit Proportion
Linus Torvalds (pre-git) 1827 90.27% 18 56.25%
Al Viro 63 3.11% 2 6.25%
Linus Torvalds 56 2.77% 3 9.38%
Ondrej Zary 40 1.98% 8 25.00%
Andrew Morton 38 1.88% 1 3.12%
Total 2024 32 


/* 
        epat.c  (c) 1997-8  Grant R. Guenther <grant@torque.net>
                            Under the terms of the GNU General Public License.

	This is the low level protocol driver for the EPAT parallel
        to IDE adapter from Shuttle Technologies.  This adapter is
        used in many popular parallel port disk products such as the
        SyQuest EZ drives, the Avatar Shark and the Imation SuperDisk.
	
*/

#include <linux/module.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/wait.h>
#include <asm/io.h>
#include "pata_parport.h"

#define j44(a,b)		(((a>>4)&0x0f)+(b&0xf0))
#define j53(a,b)		(((a>>3)&0x1f)+((b<<4)&0xe0))

static int epatc8;

module_param(epatc8, int, 0);
MODULE_PARM_DESC(epatc8, "support for the Shuttle EP1284 chip, "
	"used in any recent Imation SuperDisk (LS-120) drive.");

/* cont =  0   IDE register file
   cont =  1   IDE control registers
   cont =  2   internal EPAT registers
*/

static int cont_map[3] = { 0x18, 0x10, 0 };

static void epat_write_regr(struct pi_adapter *pi, int cont, int regr, int val)

{	int r;

	r = regr + cont_map[cont];

	switch (pi->mode) {

	case 0:
	case 1:
	case 2:	w0(0x60+r); w2(1); w0(val); w2(4);
		break;

	case 3:
	case 4:
	case 5: w3(0x40+r); w4(val);
		break;

	}
}

static int epat_read_regr(struct pi_adapter *pi, int cont, int regr)

{	int  a, b, r;

	r = regr + cont_map[cont];

	switch (pi->mode) {

	case 0:	w0(r); w2(1); w2(3); 
		a = r1(); w2(4); b = r1();
		return j44(a,b);

	case 1: w0(0x40+r); w2(1); w2(4);
		a = r1(); b = r2(); w0(0xff);
		return j53(a,b);

	case 2: w0(0x20+r); w2(1); w2(0x25);
		a = r0(); w2(4);
		return a;

	case 3:
	case 4:
	case 5: w3(r); w2(0x24); a = r4(); w2(4);
		return a;

	}
	return -1;	/* never gets here */
}

static void epat_read_block(struct pi_adapter *pi, char *buf, int count)

{	int  k, ph, a, b;

	switch (pi->mode) {

	case 0:	w0(7); w2(1); w2(3); w0(0xff);
		ph = 0;
		for(k=0;k<count;k++) {
			if (k == count-1) w0(0xfd);
			w2(6+ph); a = r1();
			if (a & 8) b = a; 
			  else { w2(4+ph); b = r1(); }
			buf[k] = j44(a,b);
			ph =  1 - ph;
		}
		w0(0); w2(4);
		break;

	case 1: w0(0x47); w2(1); w2(5); w0(0xff);
		ph = 0;
		for(k=0;k<count;k++) {
			if (k == count-1) w0(0xfd); 
			w2(4+ph);
			a = r1(); b = r2();
			buf[k] = j53(a,b);
			ph = 1 - ph;
		}
		w0(0); w2(4);
		break;

	case 2: w0(0x27); w2(1); w2(0x25); w0(0);
		ph = 0;
		for(k=0;k<count-1;k++) {
			w2(0x24+ph);
			buf[k] = r0();
			ph = 1 - ph;
		}
		w2(0x26); w2(0x27); buf[count-1] = r0(); 
		w2(0x25); w2(4);
		break;

	case 3: w3(0x80); w2(0x24);
		for(k=0;k<count-1;k++) buf[k] = r4();
		w2(4); w3(0xa0); w2(0x24); buf[count-1] = r4();
		w2(4);
		break;

	case 4: w3(0x80); w2(0x24);
		for(k=0;k<(count/2)-1;k++) ((u16 *)buf)[k] = r4w();
		buf[count-2] = r4();
		w2(4); w3(0xa0); w2(0x24); buf[count-1] = r4();
		w2(4);
		break;

	case 5: w3(0x80); w2(0x24);
		for(k=0;k<(count/4)-1;k++) ((u32 *)buf)[k] = r4l();
		for(k=count-4;k<count-1;k++) buf[k] = r4();
		w2(4); w3(0xa0); w2(0x24); buf[count-1] = r4();
		w2(4);
		break;

	}
}

static void epat_write_block(struct pi_adapter *pi, char *buf, int count)

{	int ph, k;

	switch (pi->mode) {

	case 0:
	case 1:
	case 2: w0(0x67); w2(1); w2(5);
		ph = 0;
		for(k=0;k<count;k++) {
		  	w0(buf[k]);
			w2(4+ph);
			ph = 1 - ph;
		}
		w2(7); w2(4);
		break;

	case 3: w3(0xc0); 
		for(k=0;k<count;k++) w4(buf[k]);
		w2(4);
		break;

	case 4: w3(0xc0); 
		for(k=0;k<(count/2);k++) w4w(((u16 *)buf)[k]);
		w2(4);
		break;

	case 5: w3(0xc0); 
		for(k=0;k<(count/4);k++) w4l(((u32 *)buf)[k]);
		w2(4);
		break;

	}
}

/* these macros access the EPAT registers in native addressing */

#define	WR(r,v)		epat_write_regr(pi,2,r,v)
#define	RR(r)		(epat_read_regr(pi,2,r))

/* and these access the IDE task file */

#define WRi(r,v)         epat_write_regr(pi,0,r,v)
#define RRi(r)           (epat_read_regr(pi,0,r))

/* FIXME:  the CPP stuff should be fixed to handle multiple EPATs on a chain */

#define CPP(x) 	w2(4);w0(0x22);w0(0xaa);w0(0x55);w0(0);w0(0xff);\
                w0(0x87);w0(0x78);w0(x);w2(4);w2(5);w2(4);w0(0xff);

static void epat_connect(struct pi_adapter *pi)

{       pi->saved_r0 = r0();
        pi->saved_r2 = r2();

 	/* Initialize the chip */
	CPP(0);

	if (epatc8) {
		CPP(0x40);CPP(0xe0);
		w0(0);w2(1);w2(4);
		WR(0x8,0x12);WR(0xc,0x14);WR(0x12,0x10);
		WR(0xe,0xf);WR(0xf,4);
		/* WR(0xe,0xa);WR(0xf,4); */
		WR(0xe,0xd);WR(0xf,0);
		/* CPP(0x30); */
	}

        /* Connect to the chip */
	CPP(0xe0);
        w0(0);w2(1);w2(4); /* Idle into SPP */
        if (pi->mode >= 3) {
          w0(0);w2(1);w2(4);w2(0xc);
          /* Request EPP */
          w0(0x40);w2(6);w2(7);w2(4);w2(0xc);w2(4);
        }

	if (!epatc8) {
		WR(8,0x10); WR(0xc,0x14); WR(0xa,0x38); WR(0x12,0x10);
	}
}

static void epat_disconnect(struct pi_adapter *pi)
{	CPP(0x30);
	w0(pi->saved_r0);
	w2(pi->saved_r2);
}

static int epat_test_proto(struct pi_adapter *pi)

{       int     k, j, f, cc;
	int	e[2] = {0,0};
	char scratch[512];

        epat_connect(pi);
	cc = RR(0xd);
	epat_disconnect(pi);

	epat_connect(pi);
	for (j=0;j<2;j++) {
  	    WRi(6,0xa0+j*0x10);
            for (k=0;k<256;k++) {
                WRi(2,k^0xaa);
                WRi(3,k^0x55);
                if (RRi(2) != (k^0xaa)) e[j]++;
                }
	    }
        epat_disconnect(pi);

        f = 0;
        epat_connect(pi);
        WR(0x13,1); WR(0x13,0); WR(0xa,0x11);
        epat_read_block(pi,scratch,512);
	
        for (k=0;k<256;k++) {
            if ((scratch[2*k] & 0xff) != k) f++;
            if ((scratch[2*k+1] & 0xff) != (0xff-k)) f++;
        }
        epat_disconnect(pi);

	dev_dbg(&pi->dev, "epat: port 0x%x, mode %d, ccr %x, test=(%d,%d,%d)\n",
	       pi->port, pi->mode, cc, e[0], e[1], f);
	
        return (e[0] && e[1]) || f;
}

static void epat_log_adapter(struct pi_adapter *pi)

{	int	ver;
        char    *mode_string[6] = 
		   {"4-bit","5/3","8-bit","EPP-8","EPP-16","EPP-32"};

	epat_connect(pi);
	WR(0xa,0x38);		/* read the version code */
        ver = RR(0xb);
        epat_disconnect(pi);

	dev_info(&pi->dev, "Shuttle EPAT chip %x at 0x%x, mode %d (%s), delay %d\n",
		 ver, pi->port, pi->mode, mode_string[pi->mode], pi->delay);
}

static struct pi_protocol epat = {
	.owner		= THIS_MODULE,
	.name		= "epat",
	.max_mode	= 6,
	.epp_first	= 3,
	.default_delay	= 1,
	.max_units	= 1,
	.write_regr	= epat_write_regr,
	.read_regr	= epat_read_regr,
	.write_block	= epat_write_block,
	.read_block	= epat_read_block,
	.connect	= epat_connect,
	.disconnect	= epat_disconnect,
	.test_proto	= epat_test_proto,
	.log_adapter	= epat_log_adapter,
};

static int __init epat_init(void)
{
#ifdef CONFIG_PATA_PARPORT_EPATC8
	epatc8 = 1;
#endif
	return pata_parport_register_driver(&epat);
}

static void __exit epat_exit(void)
{
	pata_parport_unregister_driver(&epat);
}

MODULE_LICENSE("GPL");
module_init(epat_init)
module_exit(epat_exit)