1 /*********************************************************************
2 *
3 * Filename: tekram.c
4 * Version: 1.3
5 * Description: Implementation of the Tekram IrMate IR-210B dongle
6 * Status: Experimental.
7 * Author: Dag Brattli <dagb@cs.uit.no>
8 * Created at: Wed Oct 21 20:02:35 1998
9 * Modified at: Sun Oct 27 22:02:38 2002
10 * Modified by: Martin Diehl <mad@mdiehl.de>
11 *
12 * Copyright (c) 1998-1999 Dag Brattli,
13 * Copyright (c) 2002 Martin Diehl,
14 * All Rights Reserved.
15 *
16 * This program is free software; you can redistribute it and/or
17 * modify it under the terms of the GNU General Public License as
18 * published by the Free Software Foundation; either version 2 of
19 * the License, or (at your option) any later version.
20 *
21 * Neither Dag Brattli nor University of Tromsø admit liability nor
22 * provide warranty for any of this software. This material is
23 * provided "AS-IS" and at no charge.
24 *
25 ********************************************************************/
26
27 #include <linux/module.h>
28 #include <linux/delay.h>
29 #include <linux/init.h>
30
31 #include <net/irda/irda.h>
32
33 #include "sir-dev.h"
34
35 static int tekram_delay = 150; /* default is 150 ms */
36 module_param(tekram_delay, int, 0);
37 MODULE_PARM_DESC(tekram_delay, "tekram dongle write complete delay");
38
39 static int tekram_open(struct sir_dev *);
40 static int tekram_close(struct sir_dev *);
41 static int tekram_change_speed(struct sir_dev *, unsigned);
42 static int tekram_reset(struct sir_dev *);
43
44 #define TEKRAM_115200 0x00
45 #define TEKRAM_57600 0x01
46 #define TEKRAM_38400 0x02
47 #define TEKRAM_19200 0x03
48 #define TEKRAM_9600 0x04
49
50 #define TEKRAM_PW 0x10 /* Pulse select bit */
51
52 static struct dongle_driver tekram = {
53 .owner = THIS_MODULE,
54 .driver_name = "Tekram IR-210B",
55 .type = IRDA_TEKRAM_DONGLE,
56 .open = tekram_open,
57 .close = tekram_close,
58 .reset = tekram_reset,
59 .set_speed = tekram_change_speed,
60 };
61
tekram_sir_init(void)62 static int __init tekram_sir_init(void)
63 {
64 if (tekram_delay < 1 || tekram_delay > 500)
65 tekram_delay = 200;
66 pr_debug("%s - using %d ms delay\n",
67 tekram.driver_name, tekram_delay);
68 return irda_register_dongle(&tekram);
69 }
70
tekram_sir_cleanup(void)71 static void __exit tekram_sir_cleanup(void)
72 {
73 irda_unregister_dongle(&tekram);
74 }
75
tekram_open(struct sir_dev * dev)76 static int tekram_open(struct sir_dev *dev)
77 {
78 struct qos_info *qos = &dev->qos;
79
80 sirdev_set_dtr_rts(dev, TRUE, TRUE);
81
82 qos->baud_rate.bits &= IR_9600|IR_19200|IR_38400|IR_57600|IR_115200;
83 qos->min_turn_time.bits = 0x01; /* Needs at least 10 ms */
84 irda_qos_bits_to_value(qos);
85
86 /* irda thread waits 50 msec for power settling */
87
88 return 0;
89 }
90
tekram_close(struct sir_dev * dev)91 static int tekram_close(struct sir_dev *dev)
92 {
93 /* Power off dongle */
94 sirdev_set_dtr_rts(dev, FALSE, FALSE);
95
96 return 0;
97 }
98
99 /*
100 * Function tekram_change_speed (dev, state, speed)
101 *
102 * Set the speed for the Tekram IRMate 210 type dongle. Warning, this
103 * function must be called with a process context!
104 *
105 * Algorithm
106 * 1. clear DTR
107 * 2. set RTS, and wait at least 7 us
108 * 3. send Control Byte to the IR-210 through TXD to set new baud rate
109 * wait until the stop bit of Control Byte is sent (for 9600 baud rate,
110 * it takes about 100 msec)
111 *
112 * [oops, why 100 msec? sending 1 byte (10 bits) takes 1.05 msec
113 * - is this probably to compensate for delays in tty layer?]
114 *
115 * 5. clear RTS (return to NORMAL Operation)
116 * 6. wait at least 50 us, new setting (baud rate, etc) takes effect here
117 * after
118 */
119
120 #define TEKRAM_STATE_WAIT_SPEED (SIRDEV_STATE_DONGLE_SPEED + 1)
121
tekram_change_speed(struct sir_dev * dev,unsigned speed)122 static int tekram_change_speed(struct sir_dev *dev, unsigned speed)
123 {
124 unsigned state = dev->fsm.substate;
125 unsigned delay = 0;
126 u8 byte;
127 static int ret = 0;
128
129 switch(state) {
130 case SIRDEV_STATE_DONGLE_SPEED:
131
132 switch (speed) {
133 default:
134 speed = 9600;
135 ret = -EINVAL;
136 /* fall thru */
137 case 9600:
138 byte = TEKRAM_PW|TEKRAM_9600;
139 break;
140 case 19200:
141 byte = TEKRAM_PW|TEKRAM_19200;
142 break;
143 case 38400:
144 byte = TEKRAM_PW|TEKRAM_38400;
145 break;
146 case 57600:
147 byte = TEKRAM_PW|TEKRAM_57600;
148 break;
149 case 115200:
150 byte = TEKRAM_115200;
151 break;
152 }
153
154 /* Set DTR, Clear RTS */
155 sirdev_set_dtr_rts(dev, TRUE, FALSE);
156
157 /* Wait at least 7us */
158 udelay(14);
159
160 /* Write control byte */
161 sirdev_raw_write(dev, &byte, 1);
162
163 dev->speed = speed;
164
165 state = TEKRAM_STATE_WAIT_SPEED;
166 delay = tekram_delay;
167 break;
168
169 case TEKRAM_STATE_WAIT_SPEED:
170 /* Set DTR, Set RTS */
171 sirdev_set_dtr_rts(dev, TRUE, TRUE);
172 udelay(50);
173 break;
174
175 default:
176 net_err_ratelimited("%s - undefined state %d\n",
177 __func__, state);
178 ret = -EINVAL;
179 break;
180 }
181
182 dev->fsm.substate = state;
183 return (delay > 0) ? delay : ret;
184 }
185
186 /*
187 * Function tekram_reset (driver)
188 *
189 * This function resets the tekram dongle. Warning, this function
190 * must be called with a process context!!
191 *
192 * Algorithm:
193 * 0. Clear RTS and DTR, and wait 50 ms (power off the IR-210 )
194 * 1. clear RTS
195 * 2. set DTR, and wait at least 1 ms
196 * 3. clear DTR to SPACE state, wait at least 50 us for further
197 * operation
198 */
199
tekram_reset(struct sir_dev * dev)200 static int tekram_reset(struct sir_dev *dev)
201 {
202 /* Clear DTR, Set RTS */
203 sirdev_set_dtr_rts(dev, FALSE, TRUE);
204
205 /* Should sleep 1 ms */
206 msleep(1);
207
208 /* Set DTR, Set RTS */
209 sirdev_set_dtr_rts(dev, TRUE, TRUE);
210
211 /* Wait at least 50 us */
212 udelay(75);
213
214 dev->speed = 9600;
215
216 return 0;
217 }
218
219 MODULE_AUTHOR("Dag Brattli <dagb@cs.uit.no>");
220 MODULE_DESCRIPTION("Tekram IrMate IR-210B dongle driver");
221 MODULE_LICENSE("GPL");
222 MODULE_ALIAS("irda-dongle-0"); /* IRDA_TEKRAM_DONGLE */
223
224 module_init(tekram_sir_init);
225 module_exit(tekram_sir_cleanup);
226