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 IRDA_DEBUG(1, "%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 IRDA_DEBUG(2, "%s()\n", __func__);
81
82 sirdev_set_dtr_rts(dev, TRUE, TRUE);
83
84 qos->baud_rate.bits &= IR_9600|IR_19200|IR_38400|IR_57600|IR_115200;
85 qos->min_turn_time.bits = 0x01; /* Needs at least 10 ms */
86 irda_qos_bits_to_value(qos);
87
88 /* irda thread waits 50 msec for power settling */
89
90 return 0;
91 }
92
tekram_close(struct sir_dev * dev)93 static int tekram_close(struct sir_dev *dev)
94 {
95 IRDA_DEBUG(2, "%s()\n", __func__);
96
97 /* Power off dongle */
98 sirdev_set_dtr_rts(dev, FALSE, FALSE);
99
100 return 0;
101 }
102
103 /*
104 * Function tekram_change_speed (dev, state, speed)
105 *
106 * Set the speed for the Tekram IRMate 210 type dongle. Warning, this
107 * function must be called with a process context!
108 *
109 * Algorithm
110 * 1. clear DTR
111 * 2. set RTS, and wait at least 7 us
112 * 3. send Control Byte to the IR-210 through TXD to set new baud rate
113 * wait until the stop bit of Control Byte is sent (for 9600 baud rate,
114 * it takes about 100 msec)
115 *
116 * [oops, why 100 msec? sending 1 byte (10 bits) takes 1.05 msec
117 * - is this probably to compensate for delays in tty layer?]
118 *
119 * 5. clear RTS (return to NORMAL Operation)
120 * 6. wait at least 50 us, new setting (baud rate, etc) takes effect here
121 * after
122 */
123
124 #define TEKRAM_STATE_WAIT_SPEED (SIRDEV_STATE_DONGLE_SPEED + 1)
125
tekram_change_speed(struct sir_dev * dev,unsigned speed)126 static int tekram_change_speed(struct sir_dev *dev, unsigned speed)
127 {
128 unsigned state = dev->fsm.substate;
129 unsigned delay = 0;
130 u8 byte;
131 static int ret = 0;
132
133 IRDA_DEBUG(2, "%s()\n", __func__);
134
135 switch(state) {
136 case SIRDEV_STATE_DONGLE_SPEED:
137
138 switch (speed) {
139 default:
140 speed = 9600;
141 ret = -EINVAL;
142 /* fall thru */
143 case 9600:
144 byte = TEKRAM_PW|TEKRAM_9600;
145 break;
146 case 19200:
147 byte = TEKRAM_PW|TEKRAM_19200;
148 break;
149 case 38400:
150 byte = TEKRAM_PW|TEKRAM_38400;
151 break;
152 case 57600:
153 byte = TEKRAM_PW|TEKRAM_57600;
154 break;
155 case 115200:
156 byte = TEKRAM_115200;
157 break;
158 }
159
160 /* Set DTR, Clear RTS */
161 sirdev_set_dtr_rts(dev, TRUE, FALSE);
162
163 /* Wait at least 7us */
164 udelay(14);
165
166 /* Write control byte */
167 sirdev_raw_write(dev, &byte, 1);
168
169 dev->speed = speed;
170
171 state = TEKRAM_STATE_WAIT_SPEED;
172 delay = tekram_delay;
173 break;
174
175 case TEKRAM_STATE_WAIT_SPEED:
176 /* Set DTR, Set RTS */
177 sirdev_set_dtr_rts(dev, TRUE, TRUE);
178 udelay(50);
179 break;
180
181 default:
182 IRDA_ERROR("%s - undefined state %d\n", __func__, state);
183 ret = -EINVAL;
184 break;
185 }
186
187 dev->fsm.substate = state;
188 return (delay > 0) ? delay : ret;
189 }
190
191 /*
192 * Function tekram_reset (driver)
193 *
194 * This function resets the tekram dongle. Warning, this function
195 * must be called with a process context!!
196 *
197 * Algorithm:
198 * 0. Clear RTS and DTR, and wait 50 ms (power off the IR-210 )
199 * 1. clear RTS
200 * 2. set DTR, and wait at least 1 ms
201 * 3. clear DTR to SPACE state, wait at least 50 us for further
202 * operation
203 */
204
tekram_reset(struct sir_dev * dev)205 static int tekram_reset(struct sir_dev *dev)
206 {
207 IRDA_DEBUG(2, "%s()\n", __func__);
208
209 /* Clear DTR, Set RTS */
210 sirdev_set_dtr_rts(dev, FALSE, TRUE);
211
212 /* Should sleep 1 ms */
213 msleep(1);
214
215 /* Set DTR, Set RTS */
216 sirdev_set_dtr_rts(dev, TRUE, TRUE);
217
218 /* Wait at least 50 us */
219 udelay(75);
220
221 dev->speed = 9600;
222
223 return 0;
224 }
225
226 MODULE_AUTHOR("Dag Brattli <dagb@cs.uit.no>");
227 MODULE_DESCRIPTION("Tekram IrMate IR-210B dongle driver");
228 MODULE_LICENSE("GPL");
229 MODULE_ALIAS("irda-dongle-0"); /* IRDA_TEKRAM_DONGLE */
230
231 module_init(tekram_sir_init);
232 module_exit(tekram_sir_cleanup);
233