on20.c

  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
 37static 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
 60static 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
 69static 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
 82static 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
 89static 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
107static 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
119static 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
128static 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
144MODULE_LICENSE("GPL");
145MODULE_AUTHOR("Grant R. Guenther <grant@torque.net>");
146MODULE_DESCRIPTION("Onspec 90c20 parallel port IDE adapter protocol driver");
147module_pata_parport_driver(on20);