1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * (c) 1997-1998 Grant R. Guenther <grant@torque.net>
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 #include <linux/module.h>
12 #include <linux/init.h>
13 #include <linux/delay.h>
14 #include <linux/kernel.h>
15 #include <linux/types.h>
16 #include <linux/wait.h>
17 #include <asm/io.h>
18 #include "pata_parport.h"
19
20 #define j44(a, b) (((a >> 4) & 0x0f) + (b & 0xf0))
21 #define j53(a, b) (((a >> 3) & 0x1f) + ((b << 4) & 0xe0))
22
23 static int epatc8;
24
25 module_param(epatc8, int, 0);
26 MODULE_PARM_DESC(epatc8,
27 "support for the Shuttle EP1284 chip, "
28 "used in any recent Imation SuperDisk (LS-120) drive.");
29
30 /*
31 * cont = 0 IDE register file
32 * cont = 1 IDE control registers
33 * cont = 2 internal EPAT registers
34 */
35 static int cont_map[3] = { 0x18, 0x10, 0 };
36
epat_write_regr(struct pi_adapter * pi,int cont,int regr,int val)37 static void epat_write_regr(struct pi_adapter *pi, int cont, int regr, int val)
38 {
39 int r = regr + cont_map[cont];
40
41 switch (pi->mode) {
42 case 0:
43 case 1:
44 case 2:
45 w0(0x60+r); w2(1); w0(val); w2(4);
46 break;
47 case 3:
48 case 4:
49 case 5:
50 w3(0x40+r); w4(val);
51 break;
52 }
53 }
54
epat_read_regr(struct pi_adapter * pi,int cont,int regr)55 static int epat_read_regr(struct pi_adapter *pi, int cont, int regr)
56 {
57 int a, b, r;
58
59 r = regr + cont_map[cont];
60
61 switch (pi->mode) {
62
63 case 0:
64 w0(r); w2(1); w2(3);
65 a = r1(); w2(4); b = r1();
66 return j44(a, b);
67 case 1:
68 w0(0x40+r); w2(1); w2(4);
69 a = r1(); b = r2(); w0(0xff);
70 return j53(a, b);
71 case 2:
72 w0(0x20+r); w2(1); w2(0x25);
73 a = r0(); w2(4);
74 return a;
75 case 3:
76 case 4:
77 case 5:
78 w3(r); w2(0x24); a = r4(); w2(4);
79 return a;
80 }
81
82 return -1; /* never gets here */
83 }
84
epat_read_block(struct pi_adapter * pi,char * buf,int count)85 static void epat_read_block(struct pi_adapter *pi, char *buf, int count)
86 {
87 int k, ph, a, b;
88
89 switch (pi->mode) {
90
91 case 0:
92 w0(7); w2(1); w2(3); w0(0xff);
93 ph = 0;
94 for (k = 0; k < count; k++) {
95 if (k == count-1)
96 w0(0xfd);
97 w2(6 + ph); a = r1();
98 if (a & 8) {
99 b = a;
100 } else {
101 w2(4+ph); b = r1();
102 }
103 buf[k] = j44(a, b);
104 ph = 1 - ph;
105 }
106 w0(0); w2(4);
107 break;
108
109 case 1:
110 w0(0x47); w2(1); w2(5); w0(0xff);
111 ph = 0;
112 for (k = 0; k < count; k++) {
113 if (k == count - 1)
114 w0(0xfd);
115 w2(4 + ph);
116 a = r1(); b = r2();
117 buf[k] = j53(a, b);
118 ph = 1 - ph;
119 }
120 w0(0); w2(4);
121 break;
122
123 case 2:
124 w0(0x27); w2(1); w2(0x25); w0(0);
125 ph = 0;
126 for (k = 0; k < count - 1; k++) {
127 w2(0x24 + ph);
128 buf[k] = r0();
129 ph = 1 - ph;
130 }
131 w2(0x26); w2(0x27);
132 buf[count - 1] = r0();
133 w2(0x25); w2(4);
134 break;
135
136 case 3:
137 w3(0x80); w2(0x24);
138 for (k = 0; k < count - 1; k++)
139 buf[k] = r4();
140 w2(4); w3(0xa0); w2(0x24);
141 buf[count - 1] = r4();
142 w2(4);
143 break;
144
145 case 4:
146 w3(0x80); w2(0x24);
147 for (k = 0; k < count / 2 - 1; k++)
148 ((u16 *)buf)[k] = r4w();
149 buf[count - 2] = r4();
150 w2(4); w3(0xa0); w2(0x24);
151 buf[count - 1] = r4();
152 w2(4);
153 break;
154
155 case 5:
156 w3(0x80); w2(0x24);
157 for (k = 0; k < count / 4 - 1; k++)
158 ((u32 *)buf)[k] = r4l();
159 for (k = count - 4; k < count - 1; k++)
160 buf[k] = r4();
161 w2(4); w3(0xa0); w2(0x24);
162 buf[count - 1] = r4();
163 w2(4);
164 break;
165 }
166 }
167
epat_write_block(struct pi_adapter * pi,char * buf,int count)168 static void epat_write_block(struct pi_adapter *pi, char *buf, int count)
169 {
170 int ph, k;
171
172 switch (pi->mode) {
173 case 0:
174 case 1:
175 case 2:
176 w0(0x67); w2(1); w2(5);
177 ph = 0;
178 for (k = 0; k < count; k++) {
179 w0(buf[k]);
180 w2(4 + ph);
181 ph = 1 - ph;
182 }
183 w2(7); w2(4);
184 break;
185 case 3:
186 w3(0xc0);
187 for (k = 0; k < count; k++)
188 w4(buf[k]);
189 w2(4);
190 break;
191 case 4:
192 w3(0xc0);
193 for (k = 0; k < count / 2; k++)
194 w4w(((u16 *)buf)[k]);
195 w2(4);
196 break;
197 case 5:
198 w3(0xc0);
199 for (k = 0; k < count / 4; k++)
200 w4l(((u32 *)buf)[k]);
201 w2(4);
202 break;
203 }
204 }
205
206 /* these macros access the EPAT registers in native addressing */
207
208 #define WR(r, v) epat_write_regr(pi, 2, r, v)
209 #define RR(r) epat_read_regr(pi, 2, r)
210
211 /* and these access the IDE task file */
212
213 #define WRi(r, v) epat_write_regr(pi, 0, r, v)
214 #define RRi(r) epat_read_regr(pi, 0, r)
215
216 /* FIXME: the CPP stuff should be fixed to handle multiple EPATs on a chain */
217
218 #define CPP(x) \
219 do { \
220 w2(4); w0(0x22); w0(0xaa); \
221 w0(0x55); w0(0); w0(0xff); \
222 w0(0x87); w0(0x78); w0(x); \
223 w2(4); w2(5); w2(4); w0(0xff); \
224 } while (0)
225
epat_connect(struct pi_adapter * pi)226 static void epat_connect(struct pi_adapter *pi)
227 {
228 pi->saved_r0 = r0();
229 pi->saved_r2 = r2();
230
231 /* Initialize the chip */
232 CPP(0);
233
234 if (epatc8) {
235 CPP(0x40); CPP(0xe0);
236 w0(0); w2(1); w2(4);
237 WR(0x8, 0x12);
238 WR(0xc, 0x14);
239 WR(0x12, 0x10);
240 WR(0xe, 0xf);
241 WR(0xf, 4);
242 /* WR(0xe,0xa);WR(0xf,4); */
243 WR(0xe, 0xd);
244 WR(0xf, 0);
245 /* CPP(0x30); */
246 }
247
248 /* Connect to the chip */
249 CPP(0xe0);
250 w0(0); w2(1); w2(4); /* Idle into SPP */
251 if (pi->mode >= 3) {
252 w0(0); w2(1); w2(4); w2(0xc);
253 /* Request EPP */
254 w0(0x40); w2(6); w2(7); w2(4); w2(0xc); w2(4);
255 }
256
257 if (!epatc8) {
258 WR(8, 0x10);
259 WR(0xc, 0x14);
260 WR(0xa, 0x38);
261 WR(0x12, 0x10);
262 }
263 }
264
epat_disconnect(struct pi_adapter * pi)265 static void epat_disconnect(struct pi_adapter *pi)
266 {
267 CPP(0x30);
268 w0(pi->saved_r0);
269 w2(pi->saved_r2);
270 }
271
epat_test_proto(struct pi_adapter * pi)272 static int epat_test_proto(struct pi_adapter *pi)
273 {
274 int k, j, f, cc;
275 int e[2] = { 0, 0 };
276 char scratch[512];
277
278 epat_connect(pi);
279 cc = RR(0xd);
280 epat_disconnect(pi);
281
282 epat_connect(pi);
283 for (j=0;j<2;j++) {
284 WRi(6, 0xa0 + j * 0x10);
285 for (k = 0; k < 256; k++) {
286 WRi(2, k ^ 0xaa);
287 WRi(3, k ^ 0x55);
288 if (RRi(2) != (k ^ 0xaa))
289 e[j]++;
290 }
291 }
292 epat_disconnect(pi);
293
294 f = 0;
295 epat_connect(pi);
296 WR(0x13, 1); WR(0x13, 0); WR(0xa, 0x11);
297 epat_read_block(pi, scratch, 512);
298
299 for (k = 0; k < 256; k++) {
300 if ((scratch[2 * k] & 0xff) != k)
301 f++;
302 if ((scratch[2 * k + 1] & 0xff) != 0xff - k)
303 f++;
304 }
305 epat_disconnect(pi);
306
307 dev_dbg(&pi->dev,
308 "epat: port 0x%x, mode %d, ccr %x, test=(%d,%d,%d)\n",
309 pi->port, pi->mode, cc, e[0], e[1], f);
310
311 return (e[0] && e[1]) || f;
312 }
313
epat_log_adapter(struct pi_adapter * pi)314 static void epat_log_adapter(struct pi_adapter *pi)
315 {
316 int ver;
317 char *mode_string[6] =
318 { "4-bit", "5/3", "8-bit", "EPP-8", "EPP-16", "EPP-32" };
319
320 epat_connect(pi);
321 WR(0xa, 0x38); /* read the version code */
322 ver = RR(0xb);
323 epat_disconnect(pi);
324
325 dev_info(&pi->dev,
326 "Shuttle EPAT chip %x at 0x%x, mode %d (%s), delay %d\n",
327 ver, pi->port, pi->mode, mode_string[pi->mode], pi->delay);
328 }
329
330 static struct pi_protocol epat = {
331 .owner = THIS_MODULE,
332 .name = "epat",
333 .max_mode = 6,
334 .epp_first = 3,
335 .default_delay = 1,
336 .max_units = 1,
337 .write_regr = epat_write_regr,
338 .read_regr = epat_read_regr,
339 .write_block = epat_write_block,
340 .read_block = epat_read_block,
341 .connect = epat_connect,
342 .disconnect = epat_disconnect,
343 .test_proto = epat_test_proto,
344 .log_adapter = epat_log_adapter,
345 };
346
epat_init(void)347 static int __init epat_init(void)
348 {
349 #ifdef CONFIG_PATA_PARPORT_EPATC8
350 epatc8 = 1;
351 #endif
352 return pata_parport_register_driver(&epat);
353 }
354
epat_exit(void)355 static void __exit epat_exit(void)
356 {
357 pata_parport_unregister_driver(&epat);
358 }
359
360 MODULE_LICENSE("GPL");
361 MODULE_AUTHOR("Grant R. Guenther <grant@torque.net>");
362 MODULE_DESCRIPTION("Shuttle Technologies EPAT parallel port IDE adapter "
363 "protocol driver");
364 module_init(epat_init)
365 module_exit(epat_exit)
366