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 /* seems no explicit power-on required here and reset switching it on anyway */ 67 68 qos->baud_rate.bits &= IR_9600|IR_19200|IR_38400|IR_57600|IR_115200; 69 qos->min_turn_time.bits = 0x01; 70 irda_qos_bits_to_value(qos); 71 72 return 0; 73} 74 75static int mcp2120_close(struct sir_dev *dev) 76{ 77 /* Power off dongle */ 78 /* reset and inhibit mcp2120 */ 79 sirdev_set_dtr_rts(dev, TRUE, TRUE); 80 // sirdev_set_dtr_rts(dev, FALSE, FALSE); 81 82 return 0; 83} 84 85/* 86 * Function mcp2120_change_speed (dev, speed) 87 * 88 * Set the speed for the MCP2120. 89 * 90 */ 91 92#define MCP2120_STATE_WAIT_SPEED (SIRDEV_STATE_DONGLE_SPEED+1) 93 94static int mcp2120_change_speed(struct sir_dev *dev, unsigned speed) 95{ 96 unsigned state = dev->fsm.substate; 97 unsigned delay = 0; 98 u8 control[2]; 99 static int ret = 0; 100 101 switch (state) { 102 case SIRDEV_STATE_DONGLE_SPEED: 103 /* Set DTR to enter command mode */ 104 sirdev_set_dtr_rts(dev, TRUE, FALSE); 105 udelay(500); 106 107 ret = 0; 108 switch (speed) { 109 default: 110 speed = 9600; 111 ret = -EINVAL; 112 /* fall through */ 113 case 9600: 114 control[0] = MCP2120_9600; 115 //printk("mcp2120 9600\n"); 116 break; 117 case 19200: 118 control[0] = MCP2120_19200; 119 //printk("mcp2120 19200\n"); 120 break; 121 case 34800: 122 control[0] = MCP2120_38400; 123 //printk("mcp2120 38400\n"); 124 break; 125 case 57600: 126 control[0] = MCP2120_57600; 127 //printk("mcp2120 57600\n"); 128 break; 129 case 115200: 130 control[0] = MCP2120_115200; 131 //printk("mcp2120 115200\n"); 132 break; 133 } 134 control[1] = MCP2120_COMMIT; 135 136 /* Write control bytes */ 137 sirdev_raw_write(dev, control, 2); 138 dev->speed = speed; 139 140 state = MCP2120_STATE_WAIT_SPEED; 141 delay = 100; 142 //printk("mcp2120_change_speed: dongle_speed\n"); 143 break; 144 145 case MCP2120_STATE_WAIT_SPEED: 146 /* Go back to normal mode */ 147 sirdev_set_dtr_rts(dev, FALSE, FALSE); 148 //printk("mcp2120_change_speed: mcp_wait\n"); 149 break; 150 151 default: 152 net_err_ratelimited("%s(), undefine state %d\n", 153 __func__, state); 154 ret = -EINVAL; 155 break; 156 } 157 dev->fsm.substate = state; 158 return (delay > 0) ? delay : ret; 159} 160 161/* 162 * Function mcp2120_reset (driver) 163 * 164 * This function resets the mcp2120 dongle. 165 * 166 * Info: -set RTS to reset mcp2120 167 * -set DTR to set mcp2120 software command mode 168 * -mcp2120 defaults to 9600 baud after reset 169 * 170 * Algorithm: 171 * 0. Set RTS to reset mcp2120. 172 * 1. Clear RTS and wait for device reset timer of 30 ms (max). 173 * 174 */ 175 176#define MCP2120_STATE_WAIT1_RESET (SIRDEV_STATE_DONGLE_RESET+1) 177#define MCP2120_STATE_WAIT2_RESET (SIRDEV_STATE_DONGLE_RESET+2) 178 179static int mcp2120_reset(struct sir_dev *dev) 180{ 181 unsigned state = dev->fsm.substate; 182 unsigned delay = 0; 183 int ret = 0; 184 185 switch (state) { 186 case SIRDEV_STATE_DONGLE_RESET: 187 //printk("mcp2120_reset: dongle_reset\n"); 188 /* Reset dongle by setting RTS*/ 189 sirdev_set_dtr_rts(dev, TRUE, TRUE); 190 state = MCP2120_STATE_WAIT1_RESET; 191 delay = 50; 192 break; 193 194 case MCP2120_STATE_WAIT1_RESET: 195 //printk("mcp2120_reset: mcp2120_wait1\n"); 196 /* clear RTS and wait for at least 30 ms. */ 197 sirdev_set_dtr_rts(dev, FALSE, FALSE); 198 state = MCP2120_STATE_WAIT2_RESET; 199 delay = 50; 200 break; 201 202 case MCP2120_STATE_WAIT2_RESET: 203 //printk("mcp2120_reset mcp2120_wait2\n"); 204 /* Go back to normal mode */ 205 sirdev_set_dtr_rts(dev, FALSE, FALSE); 206 break; 207 208 default: 209 net_err_ratelimited("%s(), undefined state %d\n", 210 __func__, state); 211 ret = -EINVAL; 212 break; 213 } 214 dev->fsm.substate = state; 215 return (delay > 0) ? delay : ret; 216} 217 218MODULE_AUTHOR("Felix Tang <tangf@eyetap.org>"); 219MODULE_DESCRIPTION("Microchip MCP2120"); 220MODULE_LICENSE("GPL"); 221MODULE_ALIAS("irda-dongle-9"); /* IRDA_MCP2120_DONGLE */ 222 223module_init(mcp2120_sir_init); 224module_exit(mcp2120_sir_cleanup); 225