1/*********************************************************************
2 *
3 * Filename:      ma600.c
4 * Version:       0.1
5 * Description:   Implementation of the MA600 dongle
6 * Status:        Experimental.
7 * Author:        Leung <95Etwl@alumni.ee.ust.hk> http://www.engsvr.ust/~eetwl95
8 * Created at:    Sat Jun 10 20:02:35 2000
9 * Modified at:   Sat Aug 16 09:34:13 2003
10 * Modified by:   Martin Diehl <mad@mdiehl.de> (modified for new sir_dev)
11 *
12 * Note: very thanks to Mr. Maru Wang <maru@mobileaction.com.tw> for providing
13 *       information on the MA600 dongle
14 *
15 *     Copyright (c) 2000 Leung, All Rights Reserved.
16 *
17 *     This program is free software; you can redistribute it and/or
18 *     modify it under the terms of the GNU General Public License as
19 *     published by the Free Software Foundation; either version 2 of
20 *     the License, or (at your option) any later version.
21 *
22 *     This program is distributed in the hope that it will be useful,
23 *     but WITHOUT ANY WARRANTY; without even the implied warranty of
24 *     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
25 *     GNU General Public License for more details.
26 *
27 *     You should have received a copy of the GNU General Public License
28 *     along with this program; if not, see <http://www.gnu.org/licenses/>.
29 *
30 ********************************************************************/
31
32#include <linux/module.h>
33#include <linux/delay.h>
34#include <linux/init.h>
35
36#include <net/irda/irda.h>
37
38#include "sir-dev.h"
39
40static int ma600_open(struct sir_dev *);
41static int ma600_close(struct sir_dev *);
42static int ma600_change_speed(struct sir_dev *, unsigned);
43static int ma600_reset(struct sir_dev *);
44
45/* control byte for MA600 */
46#define MA600_9600	0x00
47#define MA600_19200	0x01
48#define MA600_38400	0x02
49#define MA600_57600	0x03
50#define MA600_115200	0x04
51#define MA600_DEV_ID1	0x05
52#define MA600_DEV_ID2	0x06
53#define MA600_2400	0x08
54
55static struct dongle_driver ma600 = {
56	.owner          = THIS_MODULE,
57	.driver_name    = "MA600",
58	.type           = IRDA_MA600_DONGLE,
59	.open           = ma600_open,
60	.close          = ma600_close,
61	.reset          = ma600_reset,
62	.set_speed      = ma600_change_speed,
63};
64
65
66static int __init ma600_sir_init(void)
67{
68	return irda_register_dongle(&ma600);
69}
70
71static void __exit ma600_sir_cleanup(void)
72{
73	irda_unregister_dongle(&ma600);
74}
75
76/*
77	Power on:
78		(0) Clear RTS and DTR for 1 second
79		(1) Set RTS and DTR for 1 second
80		(2) 9600 bps now
81	Note: assume RTS, DTR are clear before
82*/
83static int ma600_open(struct sir_dev *dev)
84{
85	struct qos_info *qos = &dev->qos;
86
87	sirdev_set_dtr_rts(dev, TRUE, TRUE);
88
89	/* Explicitly set the speeds we can accept */
90	qos->baud_rate.bits &= IR_2400|IR_9600|IR_19200|IR_38400
91				|IR_57600|IR_115200;
92	/* Hm, 0x01 means 10ms - for >= 1ms we would need 0x07 */
93	qos->min_turn_time.bits = 0x01;		/* Needs at least 1 ms */
94	irda_qos_bits_to_value(qos);
95
96	/* irda thread waits 50 msec for power settling */
97
98	return 0;
99}
100
101static int ma600_close(struct sir_dev *dev)
102{
103	/* Power off dongle */
104	sirdev_set_dtr_rts(dev, FALSE, FALSE);
105
106	return 0;
107}
108
109static __u8 get_control_byte(__u32 speed)
110{
111	__u8 byte;
112
113	switch (speed) {
114	default:
115	case 115200:
116		byte = MA600_115200;
117		break;
118	case 57600:
119		byte = MA600_57600;
120		break;
121	case 38400:
122		byte = MA600_38400;
123		break;
124	case 19200:
125		byte = MA600_19200;
126		break;
127	case 9600:
128		byte = MA600_9600;
129		break;
130	case 2400:
131		byte = MA600_2400;
132		break;
133	}
134
135	return byte;
136}
137
138/*
139 * Function ma600_change_speed (dev, speed)
140 *
141 *    Set the speed for the MA600 type dongle.
142 *
143 *    The dongle has already been reset to a known state (dongle default)
144 *    We cycle through speeds by pulsing RTS low and then high.
145 */
146
147/*
148 * Function ma600_change_speed (dev, speed)
149 *
150 *    Set the speed for the MA600 type dongle.
151 *
152 *    Algorithm
153 *    1. Reset (already done by irda thread state machine)
154 *    2. clear RTS, set DTR and wait for 1ms
155 *    3. send Control Byte to the MA600 through TXD to set new baud rate
156 *       wait until the stop bit of Control Byte is sent (for 9600 baud rate,
157 *       it takes about 10 msec)
158 *    4. set RTS, set DTR (return to NORMAL Operation)
159 *    5. wait at least 10 ms, new setting (baud rate, etc) takes effect here
160 *       after
161 */
162
163/* total delays are only about 20ms - let's just sleep for now to
164 * avoid the state machine complexity before we get things working
165 */
166
167static int ma600_change_speed(struct sir_dev *dev, unsigned speed)
168{
169	u8	byte;
170
171	pr_debug("%s(), speed=%d (was %d)\n", __func__,
172		 speed, dev->speed);
173
174	/* dongle already reset, dongle and port at default speed (9600) */
175
176	/* Set RTS low for 1 ms */
177	sirdev_set_dtr_rts(dev, TRUE, FALSE);
178	mdelay(1);
179
180	/* Write control byte */
181	byte = get_control_byte(speed);
182	sirdev_raw_write(dev, &byte, sizeof(byte));
183
184	/* Wait at least 10ms: fake wait_until_sent - 10 bits at 9600 baud*/
185	msleep(15);					/* old ma600 uses 15ms */
186
187#if 1
188	/* read-back of the control byte. ma600 is the first dongle driver
189	 * which uses this so there might be some unidentified issues.
190	 * Disable this in case of problems with readback.
191	 */
192
193	sirdev_raw_read(dev, &byte, sizeof(byte));
194	if (byte != get_control_byte(speed))  {
195		net_warn_ratelimited("%s(): bad control byte read-back %02x != %02x\n",
196				     __func__, (unsigned)byte,
197				     (unsigned)get_control_byte(speed));
198		return -1;
199	}
200	else
201		pr_debug("%s() control byte write read OK\n", __func__);
202#endif
203
204	/* Set DTR, Set RTS */
205	sirdev_set_dtr_rts(dev, TRUE, TRUE);
206
207	/* Wait at least 10ms */
208	msleep(10);
209
210	/* dongle is now switched to the new speed */
211	dev->speed = speed;
212
213	return 0;
214}
215
216/*
217 * Function ma600_reset (dev)
218 *
219 *      This function resets the ma600 dongle.
220 *
221 *      Algorithm:
222 *    	  0. DTR=0, RTS=1 and wait 10 ms
223 *    	  1. DTR=1, RTS=1 and wait 10 ms
224 *        2. 9600 bps now
225 */
226
227/* total delays are only about 20ms - let's just sleep for now to
228 * avoid the state machine complexity before we get things working
229 */
230
231static int ma600_reset(struct sir_dev *dev)
232{
233	/* Reset the dongle : set DTR low for 10 ms */
234	sirdev_set_dtr_rts(dev, FALSE, TRUE);
235	msleep(10);
236
237	/* Go back to normal mode */
238	sirdev_set_dtr_rts(dev, TRUE, TRUE);
239	msleep(10);
240
241	dev->speed = 9600;      /* That's the dongle-default */
242
243	return 0;
244}
245
246MODULE_AUTHOR("Leung <95Etwl@alumni.ee.ust.hk> http://www.engsvr.ust/~eetwl95");
247MODULE_DESCRIPTION("MA600 dongle driver version 0.1");
248MODULE_LICENSE("GPL");
249MODULE_ALIAS("irda-dongle-11"); /* IRDA_MA600_DONGLE */
250
251module_init(ma600_sir_init);
252module_exit(ma600_sir_cleanup);
253
254