1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * (c) 1997-1998  Grant R. Guenther <grant@torque.net>
4 *
5 * dstr.c is a low-level protocol driver for the DataStor EP2000 parallel
6 * to IDE adapter chip.
7 */
8
9#include <linux/module.h>
10#include <linux/init.h>
11#include <linux/delay.h>
12#include <linux/kernel.h>
13#include <linux/types.h>
14#include <linux/wait.h>
15#include <asm/io.h>
16#include "pata_parport.h"
17
18/*
19 * mode codes:  0  nybble reads, 8-bit writes
20 *		1  8-bit reads and writes
21 *		2  8-bit EPP mode
22 *		3  EPP-16
23 *		4  EPP-32
24 */
25
26#define j44(a, b)  (((a >> 3) & 0x07) | ((~a >> 4) & 0x08) | \
27		    ((b << 1) & 0x70) | ((~b) & 0x80))
28
29#define P1	w2(5);w2(0xd);w2(5);w2(4);
30#define P2	w2(5);w2(7);w2(5);w2(4);
31#define P3      w2(6);w2(4);w2(6);w2(4);
32
33/*
34 * cont = 0 - access the IDE register file
35 * cont = 1 - access the IDE command set
36 */
37static int  cont_map[2] = { 0x20, 0x40 };
38
39static int dstr_read_regr(struct pi_adapter *pi, int cont, int regr)
40{
41	int a, b, r;
42
43	r = regr + cont_map[cont];
44
45	w0(0x81); P1;
46	if (pi->mode)
47		w0(0x11);
48	else
49		w0(1);
50	P2; w0(r); P1;
51
52	switch (pi->mode) {
53	case 0:
54		w2(6); a = r1(); w2(4); w2(6); b = r1(); w2(4);
55		return j44(a, b);
56	case 1:
57		w0(0); w2(0x26); a = r0(); w2(4);
58		return a;
59	case 2:
60	case 3:
61	case 4:
62		w2(0x24); a = r4(); w2(4);
63		return a;
64	}
65
66	return -1;
67}
68
69static void dstr_write_regr(struct pi_adapter *pi, int cont, int regr, int val)
70{
71	int  r = regr + cont_map[cont];
72
73	w0(0x81); P1;
74	if (pi->mode >= 2)
75		w0(0x11);
76	else
77		w0(1);
78	P2; w0(r); P1;
79
80	switch (pi->mode)  {
81	case 0:
82	case 1:
83		w0(val); w2(5); w2(7); w2(5); w2(4);
84		break;
85	case 2:
86	case 3:
87	case 4:
88		w4(val);
89		break;
90	}
91}
92
93#define  CCP(x)						\
94	do {						\
95		w0(0xff); w2(0xc); w2(4);		\
96		w0(0xaa); w0(0x55); w0(0); w0(0xff);	\
97		w0(0x87); w0(0x78);			\
98		w0(x); w2(5); w2(4);			\
99	} while (0)
100
101static void dstr_connect(struct pi_adapter *pi)
102{
103	pi->saved_r0 = r0();
104	pi->saved_r2 = r2();
105	w2(4); CCP(0xe0); w0(0xff);
106}
107
108static void dstr_disconnect(struct pi_adapter *pi)
109{
110	CCP(0x30);
111	w0(pi->saved_r0);
112	w2(pi->saved_r2);
113}
114
115static void dstr_read_block(struct pi_adapter *pi, char *buf, int count)
116{
117	int k, a, b;
118
119        w0(0x81); P1;
120	if (pi->mode)
121		w0(0x19);
122	else
123		w0(9);
124	P2; w0(0x82); P1; P3; w0(0x20); P1;
125
126	switch (pi->mode) {
127	case 0:
128		for (k = 0; k < count; k++) {
129			w2(6); a = r1(); w2(4);
130			w2(6); b = r1(); w2(4);
131			buf[k] = j44(a, b);
132		}
133		break;
134	case 1:
135		w0(0);
136		for (k = 0; k < count; k++) {
137			w2(0x26);
138			buf[k] = r0();
139			w2(0x24);
140		}
141		w2(4);
142		break;
143	case 2:
144		w2(0x24);
145		for (k = 0; k < count; k++)
146			buf[k] = r4();
147		w2(4);
148		break;
149	case 3:
150		w2(0x24);
151		for (k = 0; k < count / 2; k++)
152			((u16 *)buf)[k] = r4w();
153		w2(4);
154		break;
155	case 4:
156		w2(0x24);
157		for (k = 0; k < count / 4; k++)
158			((u32 *)buf)[k] = r4l();
159		w2(4);
160		break;
161	}
162}
163
164static void dstr_write_block(struct pi_adapter *pi, char *buf, int count)
165{
166	int k;
167
168	w0(0x81); P1;
169	if (pi->mode)
170		w0(0x19);
171	else
172		w0(9);
173	P2; w0(0x82); P1; P3; w0(0x20); P1;
174
175	switch (pi->mode) {
176	case 0:
177	case 1:
178		for (k = 0; k < count; k++) {
179			w2(5);
180			w0(buf[k]);
181			w2(7);
182		}
183		w2(5); w2(4);
184		break;
185	case 2:
186		w2(0xc5);
187		for (k = 0; k < count; k++)
188			w4(buf[k]);
189		w2(0xc4);
190		break;
191	case 3:
192		w2(0xc5);
193		for (k = 0; k < count / 2; k++)
194			w4w(((u16 *)buf)[k]);
195		w2(0xc4);
196		break;
197	case 4:
198		w2(0xc5);
199		for (k = 0; k < count / 4; k++)
200			w4l(((u32 *)buf)[k]);
201		w2(0xc4);
202		break;
203	}
204}
205
206static void dstr_log_adapter(struct pi_adapter *pi)
207
208{
209	char *mode_string[5] = { "4-bit", "8-bit", "EPP-8", "EPP-16", "EPP-32" };
210
211	dev_info(&pi->dev,
212		 "DataStor EP2000 at 0x%x, mode %d (%s), delay %d\n",
213		 pi->port, pi->mode, mode_string[pi->mode], pi->delay);
214}
215
216static struct pi_protocol dstr = {
217	.owner		= THIS_MODULE,
218	.name		= "dstr",
219	.max_mode	= 5,
220	.epp_first	= 2,
221	.default_delay	= 1,
222	.max_units	= 1,
223	.write_regr	= dstr_write_regr,
224	.read_regr	= dstr_read_regr,
225	.write_block	= dstr_write_block,
226	.read_block	= dstr_read_block,
227	.connect	= dstr_connect,
228	.disconnect	= dstr_disconnect,
229	.log_adapter	= dstr_log_adapter,
230};
231
232MODULE_LICENSE("GPL");
233MODULE_AUTHOR("Grant R. Guenther <grant@torque.net>");
234MODULE_DESCRIPTION("DataStor EP2000 parallel port IDE adapter protocol driver");
235module_pata_parport_driver(dstr);
236