1/*********************************************************************
2 *
3 *
4 * Filename:      mcp2120.c
5 * Version:       1.0
6 * Description:   Implementation for the MCP2120 (Microchip)
7 * Status:        Experimental.
8 * Author:        Felix Tang (tangf@eyetap.org)
9 * Created at:    Sun Mar 31 19:32:12 EST 2002
10 * Based on code by:   Dag Brattli <dagb@cs.uit.no>
11 *
12 *     Copyright (c) 2002 Felix Tang, All Rights Reserved.
13 *
14 *     This program is free software; you can redistribute it and/or
15 *     modify it under the terms of the GNU General Public License as
16 *     published by the Free Software Foundation; either version 2 of
17 *     the License, or (at your option) any later version.
18 *
19 ********************************************************************/
20
21#include <linux/module.h>
22#include <linux/delay.h>
23#include <linux/init.h>
24
25#include <net/irda/irda.h>
26
27#include "sir-dev.h"
28
29static int mcp2120_reset(struct sir_dev *dev);
30static int mcp2120_open(struct sir_dev *dev);
31static int mcp2120_close(struct sir_dev *dev);
32static int mcp2120_change_speed(struct sir_dev *dev, unsigned speed);
33
34#define MCP2120_9600    0x87
35#define MCP2120_19200   0x8B
36#define MCP2120_38400   0x85
37#define MCP2120_57600   0x83
38#define MCP2120_115200  0x81
39
40#define MCP2120_COMMIT  0x11
41
42static struct dongle_driver mcp2120 = {
43	.owner		= THIS_MODULE,
44	.driver_name	= "Microchip MCP2120",
45	.type		= IRDA_MCP2120_DONGLE,
46	.open		= mcp2120_open,
47	.close		= mcp2120_close,
48	.reset		= mcp2120_reset,
49	.set_speed	= mcp2120_change_speed,
50};
51
52static int __init mcp2120_sir_init(void)
53{
54	return irda_register_dongle(&mcp2120);
55}
56
57static void __exit mcp2120_sir_cleanup(void)
58{
59	irda_unregister_dongle(&mcp2120);
60}
61
62static int mcp2120_open(struct sir_dev *dev)
63{
64	struct qos_info *qos = &dev->qos;
65
66	IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
67
68	/* seems no explicit power-on required here and reset switching it on anyway */
69
70	qos->baud_rate.bits &= IR_9600|IR_19200|IR_38400|IR_57600|IR_115200;
71	qos->min_turn_time.bits = 0x01;
72	irda_qos_bits_to_value(qos);
73
74	return 0;
75}
76
77static int mcp2120_close(struct sir_dev *dev)
78{
79	IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
80
81	/* Power off dongle */
82        /* reset and inhibit mcp2120 */
83	sirdev_set_dtr_rts(dev, TRUE, TRUE);
84	// sirdev_set_dtr_rts(dev, FALSE, FALSE);
85
86	return 0;
87}
88
89/*
90 * Function mcp2120_change_speed (dev, speed)
91 *
92 *    Set the speed for the MCP2120.
93 *
94 */
95
96#define MCP2120_STATE_WAIT_SPEED	(SIRDEV_STATE_DONGLE_SPEED+1)
97
98static int mcp2120_change_speed(struct sir_dev *dev, unsigned speed)
99{
100	unsigned state = dev->fsm.substate;
101	unsigned delay = 0;
102	u8 control[2];
103	static int ret = 0;
104
105	IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
106
107	switch (state) {
108	case SIRDEV_STATE_DONGLE_SPEED:
109		/* Set DTR to enter command mode */
110		sirdev_set_dtr_rts(dev, TRUE, FALSE);
111                udelay(500);
112
113		ret = 0;
114		switch (speed) {
115		default:
116			speed = 9600;
117			ret = -EINVAL;
118			/* fall through */
119		case 9600:
120			control[0] = MCP2120_9600;
121                        //printk("mcp2120 9600\n");
122			break;
123		case 19200:
124			control[0] = MCP2120_19200;
125                        //printk("mcp2120 19200\n");
126			break;
127		case 34800:
128			control[0] = MCP2120_38400;
129                        //printk("mcp2120 38400\n");
130			break;
131		case 57600:
132			control[0] = MCP2120_57600;
133                        //printk("mcp2120 57600\n");
134			break;
135		case 115200:
136                        control[0] = MCP2120_115200;
137                        //printk("mcp2120 115200\n");
138			break;
139		}
140		control[1] = MCP2120_COMMIT;
141
142		/* Write control bytes */
143		sirdev_raw_write(dev, control, 2);
144		dev->speed = speed;
145
146		state = MCP2120_STATE_WAIT_SPEED;
147		delay = 100;
148                //printk("mcp2120_change_speed: dongle_speed\n");
149		break;
150
151	case MCP2120_STATE_WAIT_SPEED:
152		/* Go back to normal mode */
153		sirdev_set_dtr_rts(dev, FALSE, FALSE);
154                //printk("mcp2120_change_speed: mcp_wait\n");
155		break;
156
157	default:
158		IRDA_ERROR("%s(), undefine state %d\n", __FUNCTION__, state);
159		ret = -EINVAL;
160		break;
161	}
162	dev->fsm.substate = state;
163	return (delay > 0) ? delay : ret;
164}
165
166/*
167 * Function mcp2120_reset (driver)
168 *
169 *      This function resets the mcp2120 dongle.
170 *
171 *      Info: -set RTS to reset mcp2120
172 *            -set DTR to set mcp2120 software command mode
173 *            -mcp2120 defaults to 9600 baud after reset
174 *
175 *      Algorithm:
176 *      0. Set RTS to reset mcp2120.
177 *      1. Clear RTS and wait for device reset timer of 30 ms (max).
178 *
179 */
180
181#define MCP2120_STATE_WAIT1_RESET	(SIRDEV_STATE_DONGLE_RESET+1)
182#define MCP2120_STATE_WAIT2_RESET	(SIRDEV_STATE_DONGLE_RESET+2)
183
184static int mcp2120_reset(struct sir_dev *dev)
185{
186	unsigned state = dev->fsm.substate;
187	unsigned delay = 0;
188	int ret = 0;
189
190	IRDA_DEBUG(2, "%s()\n", __FUNCTION__);
191
192	switch (state) {
193	case SIRDEV_STATE_DONGLE_RESET:
194                //printk("mcp2120_reset: dongle_reset\n");
195		/* Reset dongle by setting RTS*/
196		sirdev_set_dtr_rts(dev, TRUE, TRUE);
197		state = MCP2120_STATE_WAIT1_RESET;
198		delay = 50;
199		break;
200
201	case MCP2120_STATE_WAIT1_RESET:
202                //printk("mcp2120_reset: mcp2120_wait1\n");
203                /* clear RTS and wait for at least 30 ms. */
204		sirdev_set_dtr_rts(dev, FALSE, FALSE);
205		state = MCP2120_STATE_WAIT2_RESET;
206		delay = 50;
207		break;
208
209	case MCP2120_STATE_WAIT2_RESET:
210                //printk("mcp2120_reset mcp2120_wait2\n");
211		/* Go back to normal mode */
212		sirdev_set_dtr_rts(dev, FALSE, FALSE);
213		break;
214
215	default:
216		IRDA_ERROR("%s(), undefined state %d\n", __FUNCTION__, state);
217		ret = -EINVAL;
218		break;
219	}
220	dev->fsm.substate = state;
221	return (delay > 0) ? delay : ret;
222}
223
224MODULE_AUTHOR("Felix Tang <tangf@eyetap.org>");
225MODULE_DESCRIPTION("Microchip MCP2120");
226MODULE_LICENSE("GPL");
227MODULE_ALIAS("irda-dongle-9"); /* IRDA_MCP2120_DONGLE */
228
229module_init(mcp2120_sir_init);
230module_exit(mcp2120_sir_cleanup);
231