1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * (c) 1997-1998 Grant R. Guenther <grant@torque.net>
4 *
5 * comm.c is a low-level protocol driver for some older models of the DataStor
6 * "Commuter" parallel to IDE adapter. Some of the parallel port devices
7 * marketed by Arista currently use this adapter.
8 */
9
10 #include <linux/module.h>
11 #include <linux/init.h>
12 #include <linux/delay.h>
13 #include <linux/kernel.h>
14 #include <linux/types.h>
15 #include <linux/wait.h>
16 #include <asm/io.h>
17 #include "pata_parport.h"
18
19 /*
20 * mode codes: 0 nybble reads, 8-bit writes
21 * 1 8-bit reads and writes
22 * 2 8-bit EPP mode
23 */
24
25 #define j44(a, b) (((a >> 3) & 0x0f) | ((b << 1) & 0xf0))
26
27 #define P1 w2(5);w2(0xd);w2(0xd);w2(5);w2(4);
28 #define P2 w2(5);w2(7);w2(7);w2(5);w2(4);
29
30 /*
31 * cont = 0 - access the IDE register file
32 * cont = 1 - access the IDE command set
33 */
34 static int cont_map[2] = { 0x08, 0x10 };
35
comm_read_regr(struct pi_adapter * pi,int cont,int regr)36 static int comm_read_regr(struct pi_adapter *pi, int cont, int regr)
37 {
38 int l, h, r;
39
40 r = regr + cont_map[cont];
41
42 switch (pi->mode) {
43 case 0:
44 w0(r); P1; w0(0);
45 w2(6); l = r1(); w0(0x80); h = r1(); w2(4);
46 return j44(l, h);
47
48 case 1:
49 w0(r+0x20); P1;
50 w0(0); w2(0x26); h = r0(); w2(4);
51 return h;
52
53 case 2:
54 case 3:
55 case 4:
56 w3(r+0x20); (void)r1();
57 w2(0x24); h = r4(); w2(4);
58 return h;
59 }
60
61 return -1;
62 }
63
comm_write_regr(struct pi_adapter * pi,int cont,int regr,int val)64 static void comm_write_regr(struct pi_adapter *pi, int cont, int regr, int val)
65 {
66 int r = regr + cont_map[cont];
67
68 switch (pi->mode) {
69 case 0:
70 case 1:
71 w0(r); P1; w0(val); P2;
72 break;
73 case 2:
74 case 3:
75 case 4:
76 w3(r); (void)r1(); w4(val);
77 break;
78 }
79 }
80
comm_connect(struct pi_adapter * pi)81 static void comm_connect(struct pi_adapter *pi)
82 {
83 pi->saved_r0 = r0();
84 pi->saved_r2 = r2();
85 w2(4); w0(0xff); w2(6);
86 w2(4); w0(0xaa); w2(6);
87 w2(4); w0(0x00); w2(6);
88 w2(4); w0(0x87); w2(6);
89 w2(4); w0(0xe0); w2(0xc); w2(0xc); w2(4);
90 }
91
comm_disconnect(struct pi_adapter * pi)92 static void comm_disconnect(struct pi_adapter *pi)
93 {
94 w2(0); w2(0); w2(0); w2(4);
95 w0(pi->saved_r0);
96 w2(pi->saved_r2);
97 }
98
comm_read_block(struct pi_adapter * pi,char * buf,int count)99 static void comm_read_block(struct pi_adapter *pi, char *buf, int count)
100 {
101 int i, l, h;
102
103 switch (pi->mode) {
104 case 0:
105 w0(0x48); P1;
106 for (i = 0; i < count; i++) {
107 w0(0); w2(6); l = r1();
108 w0(0x80); h = r1(); w2(4);
109 buf[i] = j44(l, h);
110 }
111 break;
112 case 1:
113 w0(0x68); P1; w0(0);
114 for (i = 0; i < count; i++) {
115 w2(0x26);
116 buf[i] = r0();
117 w2(0x24);
118 }
119 w2(4);
120 break;
121 case 2:
122 w3(0x68); (void)r1(); w2(0x24);
123 for (i = 0; i < count; i++)
124 buf[i] = r4();
125 w2(4);
126 break;
127 case 3:
128 w3(0x68); (void)r1(); w2(0x24);
129 for (i = 0; i < count / 2; i++)
130 ((u16 *)buf)[i] = r4w();
131 w2(4);
132 break;
133 case 4:
134 w3(0x68); (void)r1(); w2(0x24);
135 for (i = 0; i < count / 4; i++)
136 ((u32 *)buf)[i] = r4l();
137 w2(4);
138 break;
139 }
140 }
141
142 /* NB: Watch out for the byte swapped writes ! */
comm_write_block(struct pi_adapter * pi,char * buf,int count)143 static void comm_write_block(struct pi_adapter *pi, char *buf, int count)
144 {
145 int k;
146
147 switch (pi->mode) {
148 case 0:
149 case 1:
150 w0(0x68); P1;
151 for (k = 0; k < count; k++) {
152 w2(5);
153 w0(buf[k ^ 1]);
154 w2(7);
155 }
156 w2(5); w2(4);
157 break;
158 case 2:
159 w3(0x48); (void)r1();
160 for (k = 0; k < count; k++)
161 w4(buf[k ^ 1]);
162 break;
163 case 3:
164 w3(0x48); (void)r1();
165 for (k = 0; k < count / 2; k++)
166 w4w(swab16(((u16 *)buf)[k]));
167 break;
168 case 4:
169 w3(0x48); (void)r1();
170 for (k = 0; k < count / 4; k++)
171 w4l(swab16(((u16 *)buf)[2 * k]) |
172 swab16(((u16 *)buf)[2 * k + 1]) << 16);
173 break;
174 }
175 }
176
comm_log_adapter(struct pi_adapter * pi)177 static void comm_log_adapter(struct pi_adapter *pi)
178 {
179 char *mode_string[5] = { "4-bit", "8-bit", "EPP-8", "EPP-16", "EPP-32" };
180
181 dev_info(&pi->dev,
182 "DataStor Commuter at 0x%x, mode %d (%s), delay %d\n",
183 pi->port, pi->mode, mode_string[pi->mode], pi->delay);
184 }
185
186 static struct pi_protocol comm = {
187 .owner = THIS_MODULE,
188 .name = "comm",
189 .max_mode = 5,
190 .epp_first = 2,
191 .default_delay = 1,
192 .max_units = 1,
193 .write_regr = comm_write_regr,
194 .read_regr = comm_read_regr,
195 .write_block = comm_write_block,
196 .read_block = comm_read_block,
197 .connect = comm_connect,
198 .disconnect = comm_disconnect,
199 .log_adapter = comm_log_adapter,
200 };
201
202 MODULE_LICENSE("GPL");
203 MODULE_AUTHOR("Grant R. Guenther <grant@torque.net>");
204 MODULE_DESCRIPTION("DataStor Commuter parallel port IDE adapter protocol driver");
205 module_pata_parport_driver(comm);
206
