xref: /linux/drivers/ata/pata_parport/ktti.c (revision 249ebf3f65f8530beb2cbfb91bff1d83ba88d23c)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * (c) 1998  Grant R. Guenther <grant@torque.net>
4  *
5  * ktti.c is a low-level protocol driver for the KT Technology
6  * parallel port adapter.  This adapter is used in the "PHd"
7  * portable hard-drives.  As far as I can tell, this device
8  * supports 4-bit mode _only_.
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/types.h>
16 #include <linux/wait.h>
17 #include <asm/io.h>
18 #include "pata_parport.h"
19 
20 #define j44(a, b)	(((a >> 4) & 0x0f) | (b & 0xf0))
21 
22 /*
23  * cont = 0 - access the IDE register file
24  * cont = 1 - access the IDE command set
25  */
26 static int cont_map[2] = { 0x10, 0x08 };
27 
28 static void ktti_write_regr(struct pi_adapter *pi, int cont, int regr, int val)
29 {
30 	int r = regr + cont_map[cont];
31 
32 	w0(r); w2(0xb); w2(0xa); w2(3); w2(6);
33 	w0(val); w2(3); w0(0); w2(6); w2(0xb);
34 }
35 
36 static int ktti_read_regr(struct pi_adapter *pi, int cont, int regr)
37 {
38 	int a, b, r;
39 
40         r = regr + cont_map[cont];
41 
42 	w0(r); w2(0xb); w2(0xa); w2(9); w2(0xc); w2(9);
43 	a = r1(); w2(0xc);  b = r1(); w2(9); w2(0xc); w2(9);
44 	return j44(a, b);
45 }
46 
47 static void ktti_read_block(struct pi_adapter *pi, char *buf, int count)
48 {
49 	int k, a, b;
50 
51 	for (k = 0; k < count / 2; k++) {
52 		w0(0x10); w2(0xb); w2(0xa); w2(9); w2(0xc); w2(9);
53 		a = r1(); w2(0xc); b = r1(); w2(9);
54 		buf[2*k] = j44(a, b);
55 		a = r1(); w2(0xc); b = r1(); w2(9);
56 		buf[2*k+1] = j44(a, b);
57 	}
58 }
59 
60 static void ktti_write_block(struct pi_adapter *pi, char *buf, int count)
61 {
62 	int k;
63 
64 	for (k = 0; k < count / 2; k++) {
65 		w0(0x10); w2(0xb); w2(0xa); w2(3); w2(6);
66 		w0(buf[2 * k]); w2(3);
67 		w0(buf[2 * k + 1]); w2(6);
68 		w2(0xb);
69 	}
70 }
71 
72 static void ktti_connect(struct pi_adapter *pi)
73 {
74 	pi->saved_r0 = r0();
75 	pi->saved_r2 = r2();
76 	w2(0xb); w2(0xa); w0(0); w2(3); w2(6);
77 }
78 
79 static void ktti_disconnect(struct pi_adapter *pi)
80 {
81 	w2(0xb); w2(0xa); w0(0xa0); w2(3); w2(4);
82 	w0(pi->saved_r0);
83 	w2(pi->saved_r2);
84 }
85 
86 static void ktti_log_adapter(struct pi_adapter *pi)
87 {
88 	dev_info(&pi->dev, "KT adapter at 0x%x, delay %d\n",
89 		 pi->port, pi->delay);
90 }
91 
92 static struct pi_protocol ktti = {
93 	.owner		= THIS_MODULE,
94 	.name		= "ktti",
95 	.max_mode	= 1,
96 	.epp_first	= 2,
97 	.default_delay	= 1,
98 	.max_units	= 1,
99 	.write_regr	= ktti_write_regr,
100 	.read_regr	= ktti_read_regr,
101 	.write_block	= ktti_write_block,
102 	.read_block	= ktti_read_block,
103 	.connect	= ktti_connect,
104 	.disconnect	= ktti_disconnect,
105 	.log_adapter	= ktti_log_adapter,
106 };
107 
108 MODULE_LICENSE("GPL");
109 MODULE_AUTHOR("Grant R. Guenther <grant@torque.net>");
110 MODULE_DESCRIPTION("KT Technology parallel port IDE adapter protocol driver");
111 module_pata_parport_driver(ktti);
112