drivers/net/irda/ma600-sir.c

   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
  40 static int ma600_open(struct sir_dev *);
  41 static int ma600_close(struct sir_dev *);
  42 static int ma600_change_speed(struct sir_dev *, unsigned);
  43 static 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
  55 static 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
  66 static int __init ma600_sir_init(void)
  67 {
  68         return irda_register_dongle(&ma600);
  69 }
  70
  71 static 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 */
  83 static 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
 101 static 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
 109 static __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
 167 static 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
 231 static 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
 246 MODULE_AUTHOR("Leung <95Etwl@alumni.ee.ust.hk> http://www.engsvr.ust/~eetwl95");
 247 MODULE_DESCRIPTION("MA600 dongle driver version 0.1");
 248 MODULE_LICENSE("GPL");
 249 MODULE_ALIAS("irda-dongle-11"); /* IRDA_MA600_DONGLE */
 250
 251 module_init(ma600_sir_init);
 252 module_exit(ma600_sir_cleanup);
 253