1/*
2        epat.c  (c) 1997-8  Grant R. Guenther <grant@torque.net>
3                            Under the terms of the GNU General Public License.
4
5	This is the low level protocol driver for the EPAT parallel
6        to IDE adapter from Shuttle Technologies.  This adapter is
7        used in many popular parallel port disk products such as the
8        SyQuest EZ drives, the Avatar Shark and the Imation SuperDisk.
9
10*/
11
12/* Changes:
13
14        1.01    GRG 1998.05.06 init_proto, release_proto
15        1.02    Joshua b. Jore CPP(renamed), epat_connect, epat_disconnect
16
17*/
18
19#define EPAT_VERSION      "1.02"
20
21#include <linux/module.h>
22#include <linux/init.h>
23#include <linux/delay.h>
24#include <linux/kernel.h>
25#include <linux/types.h>
26#include <linux/wait.h>
27#include <asm/io.h>
28
29#include "paride.h"
30
31#define j44(a,b)		(((a>>4)&0x0f)+(b&0xf0))
32#define j53(a,b)		(((a>>3)&0x1f)+((b<<4)&0xe0))
33
34static int epatc8;
35
36module_param(epatc8, int, 0);
37MODULE_PARM_DESC(epatc8, "support for the Shuttle EP1284 chip, "
38	"used in any recent Imation SuperDisk (LS-120) drive.");
39
40/* cont =  0   IDE register file
41   cont =  1   IDE control registers
42   cont =  2   internal EPAT registers
43*/
44
45static int cont_map[3] = { 0x18, 0x10, 0 };
46
47static void epat_write_regr( PIA *pi, int cont, int regr, int val)
48
49{	int r;
50
51	r = regr + cont_map[cont];
52
53	switch (pi->mode) {
54
55	case 0:
56	case 1:
57	case 2:	w0(0x60+r); w2(1); w0(val); w2(4);
58		break;
59
60	case 3:
61	case 4:
62	case 5: w3(0x40+r); w4(val);
63		break;
64
65	}
66}
67
68static int epat_read_regr( PIA *pi, int cont, int regr )
69
70{	int  a, b, r;
71
72	r = regr + cont_map[cont];
73
74	switch (pi->mode) {
75
76	case 0:	w0(r); w2(1); w2(3);
77		a = r1(); w2(4); b = r1();
78		return j44(a,b);
79
80	case 1: w0(0x40+r); w2(1); w2(4);
81		a = r1(); b = r2(); w0(0xff);
82		return j53(a,b);
83
84	case 2: w0(0x20+r); w2(1); w2(0x25);
85		a = r0(); w2(4);
86		return a;
87
88	case 3:
89	case 4:
90	case 5: w3(r); w2(0x24); a = r4(); w2(4);
91		return a;
92
93	}
94	return -1;	/* never gets here */
95}
96
97static void epat_read_block( PIA *pi, char * buf, int count )
98
99{	int  k, ph, a, b;
100
101	switch (pi->mode) {
102
103	case 0:	w0(7); w2(1); w2(3); w0(0xff);
104		ph = 0;
105		for(k=0;k<count;k++) {
106			if (k == count-1) w0(0xfd);
107			w2(6+ph); a = r1();
108			if (a & 8) b = a;
109			  else { w2(4+ph); b = r1(); }
110			buf[k] = j44(a,b);
111			ph =  1 - ph;
112		}
113		w0(0); w2(4);
114		break;
115
116	case 1: w0(0x47); w2(1); w2(5); w0(0xff);
117		ph = 0;
118		for(k=0;k<count;k++) {
119			if (k == count-1) w0(0xfd);
120			w2(4+ph);
121			a = r1(); b = r2();
122			buf[k] = j53(a,b);
123			ph = 1 - ph;
124		}
125		w0(0); w2(4);
126		break;
127
128	case 2: w0(0x27); w2(1); w2(0x25); w0(0);
129		ph = 0;
130		for(k=0;k<count-1;k++) {
131			w2(0x24+ph);
132			buf[k] = r0();
133			ph = 1 - ph;
134		}
135		w2(0x26); w2(0x27); buf[count-1] = r0();
136		w2(0x25); w2(4);
137		break;
138
139	case 3: w3(0x80); w2(0x24);
140		for(k=0;k<count-1;k++) buf[k] = r4();
141		w2(4); w3(0xa0); w2(0x24); buf[count-1] = r4();
142		w2(4);
143		break;
144
145	case 4: w3(0x80); w2(0x24);
146		for(k=0;k<(count/2)-1;k++) ((u16 *)buf)[k] = r4w();
147		buf[count-2] = r4();
148		w2(4); w3(0xa0); w2(0x24); buf[count-1] = r4();
149		w2(4);
150		break;
151
152	case 5: w3(0x80); w2(0x24);
153		for(k=0;k<(count/4)-1;k++) ((u32 *)buf)[k] = r4l();
154		for(k=count-4;k<count-1;k++) buf[k] = r4();
155		w2(4); w3(0xa0); w2(0x24); buf[count-1] = r4();
156		w2(4);
157		break;
158
159	}
160}
161
162static void epat_write_block( PIA *pi, char * buf, int count )
163
164{	int ph, k;
165
166	switch (pi->mode) {
167
168	case 0:
169	case 1:
170	case 2: w0(0x67); w2(1); w2(5);
171		ph = 0;
172		for(k=0;k<count;k++) {
173		  	w0(buf[k]);
174			w2(4+ph);
175			ph = 1 - ph;
176		}
177		w2(7); w2(4);
178		break;
179
180	case 3: w3(0xc0);
181		for(k=0;k<count;k++) w4(buf[k]);
182		w2(4);
183		break;
184
185	case 4: w3(0xc0);
186		for(k=0;k<(count/2);k++) w4w(((u16 *)buf)[k]);
187		w2(4);
188		break;
189
190	case 5: w3(0xc0);
191		for(k=0;k<(count/4);k++) w4l(((u32 *)buf)[k]);
192		w2(4);
193		break;
194
195	}
196}
197
198/* these macros access the EPAT registers in native addressing */
199
200#define	WR(r,v)		epat_write_regr(pi,2,r,v)
201#define	RR(r)		(epat_read_regr(pi,2,r))
202
203/* and these access the IDE task file */
204
205#define WRi(r,v)         epat_write_regr(pi,0,r,v)
206#define RRi(r)           (epat_read_regr(pi,0,r))
207
208/* FIXME:  the CPP stuff should be fixed to handle multiple EPATs on a chain */
209
210#define CPP(x) 	w2(4);w0(0x22);w0(0xaa);w0(0x55);w0(0);w0(0xff);\
211                w0(0x87);w0(0x78);w0(x);w2(4);w2(5);w2(4);w0(0xff);
212
213static void epat_connect ( PIA *pi )
214
215{       pi->saved_r0 = r0();
216        pi->saved_r2 = r2();
217
218 	/* Initialize the chip */
219	CPP(0);
220
221	if (epatc8) {
222		CPP(0x40);CPP(0xe0);
223		w0(0);w2(1);w2(4);
224		WR(0x8,0x12);WR(0xc,0x14);WR(0x12,0x10);
225		WR(0xe,0xf);WR(0xf,4);
226		/* WR(0xe,0xa);WR(0xf,4); */
227		WR(0xe,0xd);WR(0xf,0);
228		/* CPP(0x30); */
229	}
230
231        /* Connect to the chip */
232	CPP(0xe0);
233        w0(0);w2(1);w2(4); /* Idle into SPP */
234        if (pi->mode >= 3) {
235          w0(0);w2(1);w2(4);w2(0xc);
236          /* Request EPP */
237          w0(0x40);w2(6);w2(7);w2(4);w2(0xc);w2(4);
238        }
239
240	if (!epatc8) {
241		WR(8,0x10); WR(0xc,0x14); WR(0xa,0x38); WR(0x12,0x10);
242	}
243}
244
245static void epat_disconnect (PIA *pi)
246{	CPP(0x30);
247	w0(pi->saved_r0);
248	w2(pi->saved_r2);
249}
250
251static int epat_test_proto( PIA *pi, char * scratch, int verbose )
252
253{       int     k, j, f, cc;
254	int	e[2] = {0,0};
255
256        epat_connect(pi);
257	cc = RR(0xd);
258	epat_disconnect(pi);
259
260	epat_connect(pi);
261	for (j=0;j<2;j++) {
262  	    WRi(6,0xa0+j*0x10);
263            for (k=0;k<256;k++) {
264                WRi(2,k^0xaa);
265                WRi(3,k^0x55);
266                if (RRi(2) != (k^0xaa)) e[j]++;
267                }
268	    }
269        epat_disconnect(pi);
270
271        f = 0;
272        epat_connect(pi);
273        WR(0x13,1); WR(0x13,0); WR(0xa,0x11);
274        epat_read_block(pi,scratch,512);
275
276        for (k=0;k<256;k++) {
277            if ((scratch[2*k] & 0xff) != k) f++;
278            if ((scratch[2*k+1] & 0xff) != (0xff-k)) f++;
279        }
280        epat_disconnect(pi);
281
282        if (verbose)  {
283            printk("%s: epat: port 0x%x, mode %d, ccr %x, test=(%d,%d,%d)\n",
284		   pi->device,pi->port,pi->mode,cc,e[0],e[1],f);
285	}
286
287        return (e[0] && e[1]) || f;
288}
289
290static void epat_log_adapter( PIA *pi, char * scratch, int verbose )
291
292{	int	ver;
293        char    *mode_string[6] =
294		   {"4-bit","5/3","8-bit","EPP-8","EPP-16","EPP-32"};
295
296	epat_connect(pi);
297	WR(0xa,0x38);		/* read the version code */
298        ver = RR(0xb);
299        epat_disconnect(pi);
300
301	printk("%s: epat %s, Shuttle EPAT chip %x at 0x%x, ",
302		pi->device,EPAT_VERSION,ver,pi->port);
303	printk("mode %d (%s), delay %d\n",pi->mode,
304		mode_string[pi->mode],pi->delay);
305
306}
307
308static struct pi_protocol epat = {
309	.owner		= THIS_MODULE,
310	.name		= "epat",
311	.max_mode	= 6,
312	.epp_first	= 3,
313	.default_delay	= 1,
314	.max_units	= 1,
315	.write_regr	= epat_write_regr,
316	.read_regr	= epat_read_regr,
317	.write_block	= epat_write_block,
318	.read_block	= epat_read_block,
319	.connect	= epat_connect,
320	.disconnect	= epat_disconnect,
321	.test_proto	= epat_test_proto,
322	.log_adapter	= epat_log_adapter,
323};
324
325static int __init epat_init(void)
326{
327#ifdef CONFIG_PARIDE_EPATC8
328	epatc8 = 1;
329#endif
330	return paride_register(&epat);
331}
332
333static void __exit epat_exit(void)
334{
335	paride_unregister(&epat);
336}
337
338MODULE_LICENSE("GPL");
339module_init(epat_init)
340module_exit(epat_exit)
341