drivers/net/irda/mcp2120.c

   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/tty.h>
  24 #include <linux/init.h>
  25
  26 #include <net/irda/irda.h>
  27 #include <net/irda/irda_device.h>
  28
  29 static int  mcp2120_reset(struct irda_task *task);
  30 static void mcp2120_open(dongle_t *self, struct qos_info *qos);
  31 static void mcp2120_close(dongle_t *self);
  32 static int  mcp2120_change_speed(struct irda_task *task);
  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
  42 static struct dongle_reg dongle = {
  43         .type = IRDA_MCP2120_DONGLE,
  44         .open = mcp2120_open,
  45         .close = mcp2120_close,
  46         .reset = mcp2120_reset,
  47         .change_speed = mcp2120_change_speed,
  48         .owner = THIS_MODULE,
  49 };
  50
  51 static int __init mcp2120_init(void)
  52 {
  53         return irda_device_register_dongle(&dongle);
  54 }
  55
  56 static void __exit mcp2120_cleanup(void)
  57 {
  58         irda_device_unregister_dongle(&dongle);
  59 }
  60
  61 static void mcp2120_open(dongle_t *self, struct qos_info *qos)
  62 {
  63         qos->baud_rate.bits &= IR_9600|IR_19200|IR_38400|IR_57600|IR_115200;
  64         qos->min_turn_time.bits = 0x01;
  65 }
  66
  67 static void mcp2120_close(dongle_t *self)
  68 {
  69         /* Power off dongle */
  70         /* reset and inhibit mcp2120 */
  71         self->set_dtr_rts(self->dev, TRUE, TRUE);
  72         //self->set_dtr_rts(self->dev, FALSE, FALSE);
  73 }
  74
  75 /*
  76  * Function mcp2120_change_speed (dev, speed)
  77  *
  78  *    Set the speed for the MCP2120.
  79  *
  80  */
  81 static int mcp2120_change_speed(struct irda_task *task)
  82 {
  83         dongle_t *self = (dongle_t *) task->instance;
  84         __u32 speed = (__u32) task->param;
  85         __u8 control[2];
  86         int ret = 0;
  87
  88         self->speed_task = task;
  89
  90         switch (task->state) {
  91         case IRDA_TASK_INIT:
  92                 /* Need to reset the dongle and go to 9600 bps before
  93                    programming */
  94                 //printk("Dmcp2120_change_speed irda_task_init\n");
  95                 if (irda_task_execute(self, mcp2120_reset, NULL, task,
  96                                       (void *) speed))
  97                 {
  98                         /* Dongle need more time to reset */
  99                         irda_task_next_state(task, IRDA_TASK_CHILD_WAIT);
 100
 101                         /* Give reset 1 sec to finish */
 102                         ret = msecs_to_jiffies(1000);
 103                 }
 104                 break;
 105         case IRDA_TASK_CHILD_WAIT:
 106                 IRDA_WARNING("%s(), resetting dongle timed out!\n",
 107                              __FUNCTION__);
 108                 ret = -1;
 109                 break;
 110         case IRDA_TASK_CHILD_DONE:
 111                 /* Set DTR to enter command mode */
 112                 self->set_dtr_rts(self->dev, TRUE, FALSE);
 113                 udelay(500);
 114
 115                 switch (speed) {
 116                 case 9600:
 117                 default:
 118                         control[0] = MCP2120_9600;
 119                         //printk("mcp2120 9600\n");
 120                         break;
 121                 case 19200:
 122                         control[0] = MCP2120_19200;
 123                         //printk("mcp2120 19200\n");
 124                         break;
 125                 case 34800:
 126                         control[0] = MCP2120_38400;
 127                         //printk("mcp2120 38400\n");
 128                         break;
 129                 case 57600:
 130                         control[0] = MCP2120_57600;
 131                         //printk("mcp2120 57600\n");
 132                         break;
 133                 case 115200:
 134                         control[0] = MCP2120_115200;
 135                         //printk("mcp2120 115200\n");
 136                         break;
 137                 }
 138                 control[1] = MCP2120_COMMIT;
 139
 140                 /* Write control bytes */
 141                 self->write(self->dev, control, 2);
 142
 143                 irda_task_next_state(task, IRDA_TASK_WAIT);
 144                 ret = msecs_to_jiffies(100);
 145                 //printk("mcp2120_change_speed irda_child_done\n");
 146                 break;
 147         case IRDA_TASK_WAIT:
 148                 /* Go back to normal mode */
 149                 self->set_dtr_rts(self->dev, FALSE, FALSE);
 150                 irda_task_next_state(task, IRDA_TASK_DONE);
 151                 self->speed_task = NULL;
 152                 //printk("mcp2120_change_speed irda_task_wait\n");
 153                 break;
 154         default:
 155                 IRDA_ERROR("%s(), unknown state %d\n",
 156                            __FUNCTION__, task->state);
 157                 irda_task_next_state(task, IRDA_TASK_DONE);
 158                 self->speed_task = NULL;
 159                 ret = -1;
 160                 break;
 161         }
 162         return ret;
 163 }
 164
 165 /*
 166  * Function mcp2120_reset (driver)
 167  *
 168  *      This function resets the mcp2120 dongle.
 169  *
 170  *      Info: -set RTS to reset mcp2120
 171  *            -set DTR to set mcp2120 software command mode
 172  *            -mcp2120 defaults to 9600 baud after reset
 173  *
 174  *      Algorithm:
 175  *      0. Set RTS to reset mcp2120.
 176  *      1. Clear RTS and wait for device reset timer of 30 ms (max).
 177  *
 178  */
 179
 180
 181 static int mcp2120_reset(struct irda_task *task)
 182 {
 183         dongle_t *self = (dongle_t *) task->instance;
 184         int ret = 0;
 185
 186         self->reset_task = task;
 187
 188         switch (task->state) {
 189         case IRDA_TASK_INIT:
 190                 //printk("mcp2120_reset irda_task_init\n");
 191                 /* Reset dongle by setting RTS*/
 192                 self->set_dtr_rts(self->dev, TRUE, TRUE);
 193                 irda_task_next_state(task, IRDA_TASK_WAIT1);
 194                 ret = msecs_to_jiffies(50);
 195                 break;
 196         case IRDA_TASK_WAIT1:
 197                 //printk("mcp2120_reset irda_task_wait1\n");
 198                 /* clear RTS and wait for at least 30 ms. */
 199                 self->set_dtr_rts(self->dev, FALSE, FALSE);
 200                 irda_task_next_state(task, IRDA_TASK_WAIT2);
 201                 ret = msecs_to_jiffies(50);
 202                 break;
 203         case IRDA_TASK_WAIT2:
 204                 //printk("mcp2120_reset irda_task_wait2\n");
 205                 /* Go back to normal mode */
 206                 self->set_dtr_rts(self->dev, FALSE, FALSE);
 207                 irda_task_next_state(task, IRDA_TASK_DONE);
 208                 self->reset_task = NULL;
 209                 break;
 210         default:
 211                 IRDA_ERROR("%s(), unknown state %d\n",
 212                            __FUNCTION__, task->state);
 213                 irda_task_next_state(task, IRDA_TASK_DONE);
 214                 self->reset_task = NULL;
 215                 ret = -1;
 216                 break;
 217         }
 218         return ret;
 219 }
 220
 221 MODULE_AUTHOR("Felix Tang <tangf@eyetap.org>");
 222 MODULE_DESCRIPTION("Microchip MCP2120");
 223 MODULE_LICENSE("GPL");
 224 MODULE_ALIAS("irda-dongle-9"); /* IRDA_MCP2120_DONGLE */
 225
 226 /*
 227  * Function init_module (void)
 228  *
 229  *    Initialize MCP2120 module
 230  *
 231  */
 232 module_init(mcp2120_init);
 233
 234 /*
 235  * Function cleanup_module (void)
 236  *
 237  *    Cleanup MCP2120 module
 238  *
 239  */
 240 module_exit(mcp2120_cleanup);