xref: /linux/drivers/ata/pata_parport/on20.c (revision a1c613ae4c322ddd58d5a8539dbfba2a0380a8c0)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * (c) 1996-1998  Grant R. Guenther <grant@torque.net>
4  *
5  * on20.c is a low-level protocol driver for the
6  * Onspec 90c20 parallel to IDE adapter.
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 #define op(f)					\
19 	do {					\
20 		w2(4); w0(f); w2(5); w2(0xd);	\
21 		w2(5); w2(0xd); w2(5); w2(4);	\
22 	} while (0)
23 
24 #define vl(v)					\
25 	do {					\
26 		w2(4); w0(v); w2(5);		\
27 		w2(7); w2(5); w2(4);		\
28 	} while (0)
29 
30 #define j44(a, b)	(((a >> 4) & 0x0f) | (b & 0xf0))
31 
32 /*
33  * cont = 0 - access the IDE register file
34  * cont = 1 - access the IDE command set
35  */
36 
on20_read_regr(struct pi_adapter * pi,int cont,int regr)37 static int on20_read_regr(struct pi_adapter *pi, int cont, int regr)
38 {
39 	int h, l, r;
40 
41 	r = (regr << 2) + 1 + cont;
42 
43 	op(1); vl(r); op(0);
44 
45 	switch (pi->mode) {
46 	case 0:
47 		w2(4); w2(6); l = r1();
48 		w2(4); w2(6); h = r1();
49 		w2(4); w2(6); w2(4); w2(6); w2(4);
50 		return j44(l, h);
51 	case 1:
52 		w2(4); w2(0x26); r = r0();
53 		w2(4); w2(0x26); w2(4);
54 		return r;
55 	}
56 
57 	return -1;
58 }
59 
on20_write_regr(struct pi_adapter * pi,int cont,int regr,int val)60 static void on20_write_regr(struct pi_adapter *pi, int cont, int regr, int val)
61 {
62 	int r = (regr << 2) + 1 + cont;
63 
64 	op(1); vl(r);
65 	op(0); vl(val);
66 	op(0); vl(val);
67 }
68 
on20_connect(struct pi_adapter * pi)69 static void on20_connect(struct pi_adapter *pi)
70 {
71 	pi->saved_r0 = r0();
72 	pi->saved_r2 = r2();
73 
74 	w2(4); w0(0); w2(0xc); w2(4); w2(6); w2(4); w2(6); w2(4);
75 	if (pi->mode) {
76 		op(2); vl(8); op(2); vl(9);
77 	} else {
78 		op(2); vl(0); op(2); vl(8);
79 	}
80 }
81 
on20_disconnect(struct pi_adapter * pi)82 static void on20_disconnect(struct pi_adapter *pi)
83 {
84 	w2(4); w0(7); w2(4); w2(0xc); w2(4);
85 	w0(pi->saved_r0);
86 	w2(pi->saved_r2);
87 }
88 
on20_read_block(struct pi_adapter * pi,char * buf,int count)89 static void on20_read_block(struct pi_adapter *pi, char *buf, int count)
90 {
91 	int k, l, h;
92 
93 	op(1); vl(1); op(0);
94 
95 	for (k = 0; k < count; k++) {
96 		if (pi->mode) {
97 			w2(4); w2(0x26); buf[k] = r0();
98 		} else {
99 			w2(6); l = r1(); w2(4);
100 			w2(6); h = r1(); w2(4);
101 			buf[k] = j44(l, h);
102 		}
103 	}
104 	w2(4);
105 }
106 
on20_write_block(struct pi_adapter * pi,char * buf,int count)107 static void on20_write_block(struct pi_adapter *pi, char *buf, int count)
108 {
109 	int k;
110 
111 	op(1); vl(1); op(0);
112 
113 	for (k = 0; k < count; k++) {
114 		w2(5); w0(buf[k]); w2(7);
115 	}
116 	w2(4);
117 }
118 
on20_log_adapter(struct pi_adapter * pi)119 static void on20_log_adapter(struct pi_adapter *pi)
120 {
121 	char *mode_string[2] = { "4-bit", "8-bit" };
122 
123 	dev_info(&pi->dev,
124 		 "OnSpec 90c20 at 0x%x, mode %d (%s), delay %d\n",
125 		 pi->port, pi->mode, mode_string[pi->mode], pi->delay);
126 }
127 
128 static struct pi_protocol on20 = {
129 	.owner		= THIS_MODULE,
130 	.name		= "on20",
131 	.max_mode	= 2,
132 	.epp_first	= 2,
133 	.default_delay	= 1,
134 	.max_units	= 1,
135 	.write_regr	= on20_write_regr,
136 	.read_regr	= on20_read_regr,
137 	.write_block	= on20_write_block,
138 	.read_block	= on20_read_block,
139 	.connect	= on20_connect,
140 	.disconnect	= on20_disconnect,
141 	.log_adapter	= on20_log_adapter,
142 };
143 
144 MODULE_LICENSE("GPL");
145 MODULE_AUTHOR("Grant R. Guenther <grant@torque.net>");
146 MODULE_DESCRIPTION("Onspec 90c20 parallel port IDE adapter protocol driver");
147 module_pata_parport_driver(on20);
148