xref: /openbmc/linux/drivers/ata/pata_parport/friq.c (revision a9ebfc40)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * (c) 1998    Grant R. Guenther <grant@torque.net>
4  *
5  * friq.c is a low-level protocol driver for the Freecom "IQ"
6  * parallel port IDE adapter.   Early versions of this adapter
7  * use the 'frpw' protocol.
8  *
9  * Freecom uses this adapter in a battery powered external
10  * CD-ROM drive.  It is also used in LS-120 drives by
11  * Maxell and Panasonic, and other devices.
12  *
13  * The battery powered drive requires software support to
14  * control the power to the drive.  This module enables the
15  * drive power when the high level driver (pcd) is loaded
16  * and disables it when the module is unloaded.  Note, if
17  * the friq module is built in to the kernel, the power
18  * will never be switched off, so other means should be
19  * used to conserve battery power.
20  */
21 
22 #include <linux/module.h>
23 #include <linux/init.h>
24 #include <linux/delay.h>
25 #include <linux/kernel.h>
26 #include <linux/types.h>
27 #include <linux/wait.h>
28 #include <asm/io.h>
29 #include "pata_parport.h"
30 
31 #define CMD(x)							\
32 	do {							\
33 		w2(4); w0(0xff); w0(0xff); w0(0x73); w0(0x73);	\
34 		w0(0xc9); w0(0xc9); w0(0x26);			\
35 		w0(0x26); w0(x); w0(x);				\
36 	} while (0)
37 
38 #define j44(l, h)	(((l >> 4) & 0x0f) | (h & 0xf0))
39 
40 /*
41  * cont = 0 - access the IDE register file
42  * cont = 1 - access the IDE command set
43  */
44 static int cont_map[2] = { 0x08, 0x10 };
45 
46 static int friq_read_regr(struct pi_adapter *pi, int cont, int regr)
47 {
48 	int h, l, r;
49 
50 	r = regr + cont_map[cont];
51 
52 	CMD(r);
53 	w2(6); l = r1();
54 	w2(4); h = r1();
55 	w2(4);
56 
57 	return j44(l, h);
58 }
59 
60 static void friq_write_regr(struct pi_adapter *pi, int cont, int regr, int val)
61 {
62 	int r = regr + cont_map[cont];
63 
64 	CMD(r);
65 	w0(val);
66 	w2(5); w2(7); w2(5); w2(4);
67 }
68 
69 static void friq_read_block_int(struct pi_adapter *pi, char *buf, int count, int regr)
70 {
71 	int h, l, k, ph;
72 
73 	switch (pi->mode) {
74 	case 0:
75 		CMD(regr);
76 		for (k = 0; k < count; k++) {
77 			w2(6); l = r1();
78 			w2(4); h = r1();
79 			buf[k] = j44(l, h);
80 		}
81 		w2(4);
82 		break;
83 	case 1:
84 		ph = 2;
85 		CMD(regr + 0xc0);
86 		w0(0xff);
87 		for (k = 0; k < count; k++) {
88 			w2(0xa4 + ph);
89 			buf[k] = r0();
90 			ph = 2 - ph;
91 		}
92 		w2(0xac); w2(0xa4); w2(4);
93 		break;
94 	case 2:
95 		CMD(regr + 0x80);
96 		for (k = 0; k < count - 2; k++)
97 			buf[k] = r4();
98 		w2(0xac); w2(0xa4);
99 		buf[count - 2] = r4();
100 		buf[count - 1] = r4();
101 		w2(4);
102 		break;
103 	case 3:
104 		CMD(regr + 0x80);
105 		for (k = 0; k < count / 2 - 1; k++)
106 			((u16 *)buf)[k] = r4w();
107 		w2(0xac); w2(0xa4);
108 		buf[count - 2] = r4();
109 		buf[count - 1] = r4();
110 		w2(4);
111 		break;
112 	case 4:
113 		CMD(regr + 0x80);
114 		for (k = 0; k < count / 4 - 1; k++)
115 			((u32 *)buf)[k] = r4l();
116 		buf[count - 4] = r4();
117 		buf[count - 3] = r4();
118 		w2(0xac); w2(0xa4);
119 		buf[count - 2] = r4();
120 		buf[count - 1] = r4();
121 		w2(4);
122 		break;
123 	}
124 }
125 
126 static void friq_read_block(struct pi_adapter *pi, char *buf, int count)
127 {
128 	friq_read_block_int(pi, buf, count, 0x08);
129 }
130 
131 static void friq_write_block(struct pi_adapter *pi, char *buf, int count)
132 {
133 	int k;
134 
135 	switch (pi->mode) {
136 	case 0:
137 	case 1:
138 		CMD(8); w2(5);
139 		for (k = 0; k < count; k++) {
140 			w0(buf[k]);
141 			w2(7); w2(5);
142 		}
143 		w2(4);
144 		break;
145 	case 2:
146 		CMD(0xc8); w2(5);
147 		for (k = 0; k < count; k++)
148 			w4(buf[k]);
149 		w2(4);
150 		break;
151 	case 3:
152 		CMD(0xc8); w2(5);
153 		for (k = 0; k < count / 2; k++)
154 			w4w(((u16 *)buf)[k]);
155 		w2(4);
156 		break;
157 	case 4:
158 		CMD(0xc8); w2(5);
159 		for (k = 0; k < count / 4; k++)
160 			w4l(((u32 *)buf)[k]);
161 		w2(4);
162 		break;
163 }
164 }
165 
166 static void friq_connect(struct pi_adapter *pi)
167 {
168 	pi->saved_r0 = r0();
169 	pi->saved_r2 = r2();
170 	w2(4);
171 }
172 
173 static void friq_disconnect(struct pi_adapter *pi)
174 {
175 	CMD(0x20);
176 	w0(pi->saved_r0);
177 	w2(pi->saved_r2);
178 }
179 
180 static int friq_test_proto(struct pi_adapter *pi)
181 {
182 	int j, k, r;
183 	int e[2] = { 0, 0 };
184 	char scratch[512];
185 
186 	pi->saved_r0 = r0();
187 	w0(0xff); udelay(20); CMD(0x3d); /* turn the power on */
188 	udelay(500);
189 	w0(pi->saved_r0);
190 
191 	friq_connect(pi);
192 	for (j = 0; j < 2; j++) {
193 		friq_write_regr(pi, 0, 6, 0xa0 + j * 0x10);
194 		for (k = 0; k < 256; k++) {
195 			friq_write_regr(pi, 0, 2, k ^ 0xaa);
196 			friq_write_regr(pi, 0, 3, k ^ 0x55);
197 			if (friq_read_regr(pi, 0, 2) != (k ^ 0xaa))
198 				e[j]++;
199 		}
200 	}
201 	friq_disconnect(pi);
202 
203 	friq_connect(pi);
204 	friq_read_block_int(pi, scratch, 512, 0x10);
205 	r = 0;
206 	for (k = 0; k < 128; k++) {
207 		if (scratch[k] != k)
208 			r++;
209 	}
210 	friq_disconnect(pi);
211 
212 	dev_dbg(&pi->dev,
213 		"friq: port 0x%x, mode %d, test=(%d,%d,%d)\n",
214 		pi->port, pi->mode, e[0], e[1], r);
215 
216 	return r || (e[0] && e[1]);
217 }
218 
219 static void friq_log_adapter(struct pi_adapter *pi)
220 {
221 	char *mode_string[6] = { "4-bit", "8-bit", "EPP-8", "EPP-16", "EPP-32"};
222 
223 	dev_info(&pi->dev,
224 		 "Freecom IQ ASIC-2 adapter at 0x%x, mode %d (%s), delay %d\n",
225 		 pi->port, pi->mode, mode_string[pi->mode], pi->delay);
226 
227 	pi->private = 1;
228 	friq_connect(pi);
229 	CMD(0x9e);  		/* disable sleep timer */
230 	friq_disconnect(pi);
231 }
232 
233 static void friq_release_proto(struct pi_adapter *pi)
234 {
235 	if (pi->private) {		/* turn off the power */
236 		friq_connect(pi);
237 		CMD(0x1d); CMD(0x1e);
238 		friq_disconnect(pi);
239 		pi->private = 0;
240 	}
241 }
242 
243 static struct pi_protocol friq = {
244 	.owner		= THIS_MODULE,
245 	.name		= "friq",
246 	.max_mode	= 5,
247 	.epp_first	= 2,
248 	.default_delay	= 1,
249 	.max_units	= 1,
250 	.write_regr	= friq_write_regr,
251 	.read_regr	= friq_read_regr,
252 	.write_block	= friq_write_block,
253 	.read_block	= friq_read_block,
254 	.connect	= friq_connect,
255 	.disconnect	= friq_disconnect,
256 	.test_proto	= friq_test_proto,
257 	.log_adapter	= friq_log_adapter,
258 	.release_proto	= friq_release_proto,
259 };
260 
261 MODULE_LICENSE("GPL");
262 MODULE_AUTHOR("Grant R. Guenther <grant@torque.net>");
263 MODULE_DESCRIPTION("Freecom IQ parallel port IDE adapter protocol driver");
264 module_pata_parport_driver(friq);
265