1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * (c) 1997-8  Grant R. Guenther <grant@torque.net>
4 *
5 * aten.c is a low-level protocol driver for the ATEN EH-100
6 * parallel port adapter.  The EH-100 supports 4-bit and 8-bit
7 * modes only.  There is also an EH-132 which supports EPP mode
8 * transfers.  The EH-132 is not yet supported.
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/wait.h>
16#include <linux/types.h>
17#include <asm/io.h>
18#include "pata_parport.h"
19
20#define j44(a,b)                ((((a>>4)&0x0f)|(b&0xf0))^0x88)
21
22/*
23 * cont = 0 - access the IDE register file
24 * cont = 1 - access the IDE command set
25 */
26static int  cont_map[2] = { 0x08, 0x20 };
27
28static void aten_write_regr(struct pi_adapter *pi, int cont, int regr, int val)
29{
30	int r = regr + cont_map[cont] + 0x80;
31
32	w0(r); w2(0xe); w2(6); w0(val); w2(7); w2(6); w2(0xc);
33}
34
35static int aten_read_regr(struct pi_adapter *pi, int cont, int regr)
36{
37	int  a, b, r;
38
39	r = regr + cont_map[cont] + 0x40;
40
41	switch (pi->mode) {
42
43	case 0:
44		w0(r); w2(0xe); w2(6);
45		w2(7); w2(6); w2(0);
46		a = r1(); w0(0x10); b = r1(); w2(0xc);
47		return j44(a,b);
48
49	case 1:
50		r |= 0x10;
51		w0(r); w2(0xe); w2(6); w0(0xff);
52		w2(0x27); w2(0x26); w2(0x20);
53		a = r0();
54		w2(0x26); w2(0xc);
55		return a;
56	}
57	return -1;
58}
59
60static void aten_read_block(struct pi_adapter *pi, char *buf, int count)
61{
62	int  k, a, b, c, d;
63
64	switch (pi->mode) {
65
66	case 0:
67		w0(0x48); w2(0xe); w2(6);
68		for (k = 0; k < count / 2; k++) {
69			w2(7); w2(6); w2(2);
70			a = r1(); w0(0x58); b = r1();
71			w2(0); d = r1(); w0(0x48); c = r1();
72			buf[2 * k] = j44(c, d);
73			buf[2 * k + 1] = j44(a, b);
74		}
75		w2(0xc);
76		break;
77
78	case 1:
79		w0(0x58); w2(0xe); w2(6);
80		for (k = 0; k < count / 2; k++) {
81			w2(0x27); w2(0x26); w2(0x22);
82			a = r0(); w2(0x20); b = r0();
83			buf[2 * k] = b;
84			buf[2 * k + 1] = a;
85		}
86		w2(0x26); w2(0xc);
87		break;
88	}
89}
90
91static void aten_write_block(struct pi_adapter *pi, char *buf, int count)
92{
93	int k;
94
95	w0(0x88); w2(0xe); w2(6);
96	for (k = 0; k < count / 2; k++) {
97		w0(buf[2 * k + 1]); w2(0xe); w2(6);
98		w0(buf[2 * k]); w2(7); w2(6);
99	}
100	w2(0xc);
101}
102
103static void aten_connect(struct pi_adapter *pi)
104{
105	pi->saved_r0 = r0();
106	pi->saved_r2 = r2();
107	w2(0xc);
108}
109
110static void aten_disconnect(struct pi_adapter *pi)
111{
112	w0(pi->saved_r0);
113	w2(pi->saved_r2);
114}
115
116static void aten_log_adapter(struct pi_adapter *pi)
117{
118	char *mode_string[2] = { "4-bit", "8-bit" };
119
120	dev_info(&pi->dev,
121		 "ATEN EH-100 at 0x%x, mode %d (%s), delay %d\n",
122		 pi->port, pi->mode, mode_string[pi->mode], pi->delay);
123}
124
125static struct pi_protocol aten = {
126	.owner		= THIS_MODULE,
127	.name		= "aten",
128	.max_mode	= 2,
129	.epp_first	= 2,
130	.default_delay	= 1,
131	.max_units	= 1,
132	.write_regr	= aten_write_regr,
133	.read_regr	= aten_read_regr,
134	.write_block	= aten_write_block,
135	.read_block	= aten_read_block,
136	.connect	= aten_connect,
137	.disconnect	= aten_disconnect,
138	.log_adapter	= aten_log_adapter,
139};
140
141MODULE_LICENSE("GPL");
142MODULE_AUTHOR("Grant R. Guenther <grant@torque.net>");
143MODULE_DESCRIPTION("ATEN EH-100 parallel port IDE adapter protocol driver");
144module_pata_parport_driver(aten);
145