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

   1 /*
   2  * $Id: iforce-serio.c,v 1.4 2002/01/28 22:45:00 jdeneux Exp $
   3  *
   4  *  Copyright (c) 2000-2001 Vojtech Pavlik <vojtech@ucw.cz>
   5  *  Copyright (c) 2001, 2007 Johann Deneux <johann.deneux@gmail.com>
   6  *
   7  *  USB/RS232 I-Force joysticks and wheels.
   8  */
   9
  10 /*
  11  * This program is free software; you can redistribute it and/or modify
  12  * it under the terms of the GNU General Public License as published by
  13  * the Free Software Foundation; either version 2 of the License, or
  14  * (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  24  *
  25  * Should you need to contact me, the author, you can do so either by
  26  * e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail:
  27  * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
  28  */
  29
  30 #include "iforce.h"
  31
  32 void iforce_serial_xmit(struct iforce *iforce)
  33 {
  34         unsigned char cs;
  35         int i;
  36         unsigned long flags;
  37
  38         if (test_and_set_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags)) {
  39                 set_bit(IFORCE_XMIT_AGAIN, iforce->xmit_flags);
  40                 return;
  41         }
  42
  43         spin_lock_irqsave(&iforce->xmit_lock, flags);
  44
  45 again:
  46         if (iforce->xmit.head == iforce->xmit.tail) {
  47                 clear_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags);
  48                 spin_unlock_irqrestore(&iforce->xmit_lock, flags);
  49                 return;
  50         }
  51
  52         cs = 0x2b;
  53
  54         serio_write(iforce->serio, 0x2b);
  55
  56         serio_write(iforce->serio, iforce->xmit.buf[iforce->xmit.tail]);
  57         cs ^= iforce->xmit.buf[iforce->xmit.tail];
  58         XMIT_INC(iforce->xmit.tail, 1);
  59
  60         for (i=iforce->xmit.buf[iforce->xmit.tail]; i >= 0; --i) {
  61                 serio_write(iforce->serio, iforce->xmit.buf[iforce->xmit.tail]);
  62                 cs ^= iforce->xmit.buf[iforce->xmit.tail];
  63                 XMIT_INC(iforce->xmit.tail, 1);
  64         }
  65
  66         serio_write(iforce->serio, cs);
  67
  68         if (test_and_clear_bit(IFORCE_XMIT_AGAIN, iforce->xmit_flags))
  69                 goto again;
  70
  71         clear_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags);
  72
  73         spin_unlock_irqrestore(&iforce->xmit_lock, flags);
  74 }
  75
  76 static void iforce_serio_write_wakeup(struct serio *serio)
  77 {
  78         struct iforce *iforce = serio_get_drvdata(serio);
  79
  80         iforce_serial_xmit(iforce);
  81 }
  82
  83 static irqreturn_t iforce_serio_irq(struct serio *serio,
  84                 unsigned char data, unsigned int flags)
  85 {
  86         struct iforce *iforce = serio_get_drvdata(serio);
  87
  88         if (!iforce->pkt) {
  89                 if (data == 0x2b)
  90                         iforce->pkt = 1;
  91                 goto out;
  92         }
  93
  94         if (!iforce->id) {
  95                 if (data > 3 && data != 0xff)
  96                         iforce->pkt = 0;
  97                 else
  98                         iforce->id = data;
  99                 goto out;
 100         }
 101
 102         if (!iforce->len) {
 103                 if (data > IFORCE_MAX_LENGTH) {
 104                         iforce->pkt = 0;
 105                         iforce->id = 0;
 106                 } else {
 107                         iforce->len = data;
 108                 }
 109                 goto out;
 110         }
 111
 112         if (iforce->idx < iforce->len) {
 113                 iforce->csum += iforce->data[iforce->idx++] = data;
 114                 goto out;
 115         }
 116
 117         if (iforce->idx == iforce->len) {
 118                 iforce_process_packet(iforce, (iforce->id << 8) | iforce->idx, iforce->data);
 119                 iforce->pkt = 0;
 120                 iforce->id  = 0;
 121                 iforce->len = 0;
 122                 iforce->idx = 0;
 123                 iforce->csum = 0;
 124         }
 125 out:
 126         return IRQ_HANDLED;
 127 }
 128
 129 static int iforce_serio_connect(struct serio *serio, struct serio_driver *drv)
 130 {
 131         struct iforce *iforce;
 132         int err;
 133
 134         iforce = kzalloc(sizeof(struct iforce), GFP_KERNEL);
 135         if (!iforce)
 136                 return -ENOMEM;
 137
 138         iforce->bus = IFORCE_232;
 139         iforce->serio = serio;
 140
 141         serio_set_drvdata(serio, iforce);
 142
 143         err = serio_open(serio, drv);
 144         if (err)
 145                 goto fail1;
 146
 147         err = iforce_init_device(iforce);
 148         if (err)
 149                 goto fail2;
 150
 151         return 0;
 152
 153  fail2: serio_close(serio);
 154  fail1: serio_set_drvdata(serio, NULL);
 155         kfree(iforce);
 156         return err;
 157 }
 158
 159 static void iforce_serio_disconnect(struct serio *serio)
 160 {
 161         struct iforce *iforce = serio_get_drvdata(serio);
 162
 163         input_unregister_device(iforce->dev);
 164         serio_close(serio);
 165         serio_set_drvdata(serio, NULL);
 166         kfree(iforce);
 167 }
 168
 169 static struct serio_device_id iforce_serio_ids[] = {
 170         {
 171                 .type   = SERIO_RS232,
 172                 .proto  = SERIO_IFORCE,
 173                 .id     = SERIO_ANY,
 174                 .extra  = SERIO_ANY,
 175         },
 176         { 0 }
 177 };
 178
 179 MODULE_DEVICE_TABLE(serio, iforce_serio_ids);
 180
 181 struct serio_driver iforce_serio_drv = {
 182         .driver         = {
 183                 .name   = "iforce",
 184         },
 185         .description    = "RS232 I-Force joysticks and wheels driver",
 186         .id_table       = iforce_serio_ids,
 187         .write_wakeup   = iforce_serio_write_wakeup,
 188         .interrupt      = iforce_serio_irq,
 189         .connect        = iforce_serio_connect,
 190         .disconnect     = iforce_serio_disconnect,
 191 };