drivers/input/joystick/iforce/iforce-serio.c

   1 /*
   2  *  Copyright (c) 2000-2001 Vojtech Pavlik <vojtech@ucw.cz>
   3  *  Copyright (c) 2001, 2007 Johann Deneux <johann.deneux@gmail.com>
   4  *
   5  *  USB/RS232 I-Force joysticks and wheels.
   6  */
   7
   8 /*
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License as published by
  11  * the Free Software Foundation; either version 2 of the License, or
  12  * (at your option) any later version.
  13  *
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  *
  19  * You should have received a copy of the GNU General Public License
  20  * along with this program; if not, write to the Free Software
  21  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  22  */
  23
  24 #include "iforce.h"
  25
  26 void iforce_serial_xmit(struct iforce *iforce)
  27 {
  28         unsigned char cs;
  29         int i;
  30         unsigned long flags;
  31
  32         if (test_and_set_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags)) {
  33                 set_bit(IFORCE_XMIT_AGAIN, iforce->xmit_flags);
  34                 return;
  35         }
  36
  37         spin_lock_irqsave(&iforce->xmit_lock, flags);
  38
  39 again:
  40         if (iforce->xmit.head == iforce->xmit.tail) {
  41                 clear_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags);
  42                 spin_unlock_irqrestore(&iforce->xmit_lock, flags);
  43                 return;
  44         }
  45
  46         cs = 0x2b;
  47
  48         serio_write(iforce->serio, 0x2b);
  49
  50         serio_write(iforce->serio, iforce->xmit.buf[iforce->xmit.tail]);
  51         cs ^= iforce->xmit.buf[iforce->xmit.tail];
  52         XMIT_INC(iforce->xmit.tail, 1);
  53
  54         for (i=iforce->xmit.buf[iforce->xmit.tail]; i >= 0; --i) {
  55                 serio_write(iforce->serio, iforce->xmit.buf[iforce->xmit.tail]);
  56                 cs ^= iforce->xmit.buf[iforce->xmit.tail];
  57                 XMIT_INC(iforce->xmit.tail, 1);
  58         }
  59
  60         serio_write(iforce->serio, cs);
  61
  62         if (test_and_clear_bit(IFORCE_XMIT_AGAIN, iforce->xmit_flags))
  63                 goto again;
  64
  65         clear_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags);
  66
  67         spin_unlock_irqrestore(&iforce->xmit_lock, flags);
  68 }
  69
  70 static void iforce_serio_write_wakeup(struct serio *serio)
  71 {
  72         struct iforce *iforce = serio_get_drvdata(serio);
  73
  74         iforce_serial_xmit(iforce);
  75 }
  76
  77 static irqreturn_t iforce_serio_irq(struct serio *serio,
  78                 unsigned char data, unsigned int flags)
  79 {
  80         struct iforce *iforce = serio_get_drvdata(serio);
  81
  82         if (!iforce->pkt) {
  83                 if (data == 0x2b)
  84                         iforce->pkt = 1;
  85                 goto out;
  86         }
  87
  88         if (!iforce->id) {
  89                 if (data > 3 && data != 0xff)
  90                         iforce->pkt = 0;
  91                 else
  92                         iforce->id = data;
  93                 goto out;
  94         }
  95
  96         if (!iforce->len) {
  97                 if (data > IFORCE_MAX_LENGTH) {
  98                         iforce->pkt = 0;
  99                         iforce->id = 0;
 100                 } else {
 101                         iforce->len = data;
 102                 }
 103                 goto out;
 104         }
 105
 106         if (iforce->idx < iforce->len) {
 107                 iforce->csum += iforce->data[iforce->idx++] = data;
 108                 goto out;
 109         }
 110
 111         if (iforce->idx == iforce->len) {
 112                 iforce_process_packet(iforce, (iforce->id << 8) | iforce->idx, iforce->data);
 113                 iforce->pkt = 0;
 114                 iforce->id  = 0;
 115                 iforce->len = 0;
 116                 iforce->idx = 0;
 117                 iforce->csum = 0;
 118         }
 119 out:
 120         return IRQ_HANDLED;
 121 }
 122
 123 static int iforce_serio_connect(struct serio *serio, struct serio_driver *drv)
 124 {
 125         struct iforce *iforce;
 126         int err;
 127
 128         iforce = kzalloc(sizeof(struct iforce), GFP_KERNEL);
 129         if (!iforce)
 130                 return -ENOMEM;
 131
 132         iforce->bus = IFORCE_232;
 133         iforce->serio = serio;
 134
 135         serio_set_drvdata(serio, iforce);
 136
 137         err = serio_open(serio, drv);
 138         if (err)
 139                 goto fail1;
 140
 141         err = iforce_init_device(iforce);
 142         if (err)
 143                 goto fail2;
 144
 145         return 0;
 146
 147  fail2: serio_close(serio);
 148  fail1: serio_set_drvdata(serio, NULL);
 149         kfree(iforce);
 150         return err;
 151 }
 152
 153 static void iforce_serio_disconnect(struct serio *serio)
 154 {
 155         struct iforce *iforce = serio_get_drvdata(serio);
 156
 157         input_unregister_device(iforce->dev);
 158         serio_close(serio);
 159         serio_set_drvdata(serio, NULL);
 160         kfree(iforce);
 161 }
 162
 163 static const struct serio_device_id iforce_serio_ids[] = {
 164         {
 165                 .type   = SERIO_RS232,
 166                 .proto  = SERIO_IFORCE,
 167                 .id     = SERIO_ANY,
 168                 .extra  = SERIO_ANY,
 169         },
 170         { 0 }
 171 };
 172
 173 MODULE_DEVICE_TABLE(serio, iforce_serio_ids);
 174
 175 struct serio_driver iforce_serio_drv = {
 176         .driver         = {
 177                 .name   = "iforce",
 178         },
 179         .description    = "RS232 I-Force joysticks and wheels driver",
 180         .id_table       = iforce_serio_ids,
 181         .write_wakeup   = iforce_serio_write_wakeup,
 182         .interrupt      = iforce_serio_irq,
 183         .connect        = iforce_serio_connect,
 184         .disconnect     = iforce_serio_disconnect,
 185 };