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  * Should you need to contact me, the author, you can do so either by
  24  * e-mail - mail your message to <vojtech@ucw.cz>, or by paper mail:
  25  * Vojtech Pavlik, Simunkova 1594, Prague 8, 182 00 Czech Republic
  26  */
  27
  28 #include "iforce.h"
  29
  30 void iforce_serial_xmit(struct iforce *iforce)
  31 {
  32         unsigned char cs;
  33         int i;
  34         unsigned long flags;
  35
  36         if (test_and_set_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags)) {
  37                 set_bit(IFORCE_XMIT_AGAIN, iforce->xmit_flags);
  38                 return;
  39         }
  40
  41         spin_lock_irqsave(&iforce->xmit_lock, flags);
  42
  43 again:
  44         if (iforce->xmit.head == iforce->xmit.tail) {
  45                 clear_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags);
  46                 spin_unlock_irqrestore(&iforce->xmit_lock, flags);
  47                 return;
  48         }
  49
  50         cs = 0x2b;
  51
  52         serio_write(iforce->serio, 0x2b);
  53
  54         serio_write(iforce->serio, iforce->xmit.buf[iforce->xmit.tail]);
  55         cs ^= iforce->xmit.buf[iforce->xmit.tail];
  56         XMIT_INC(iforce->xmit.tail, 1);
  57
  58         for (i=iforce->xmit.buf[iforce->xmit.tail]; i >= 0; --i) {
  59                 serio_write(iforce->serio, iforce->xmit.buf[iforce->xmit.tail]);
  60                 cs ^= iforce->xmit.buf[iforce->xmit.tail];
  61                 XMIT_INC(iforce->xmit.tail, 1);
  62         }
  63
  64         serio_write(iforce->serio, cs);
  65
  66         if (test_and_clear_bit(IFORCE_XMIT_AGAIN, iforce->xmit_flags))
  67                 goto again;
  68
  69         clear_bit(IFORCE_XMIT_RUNNING, iforce->xmit_flags);
  70
  71         spin_unlock_irqrestore(&iforce->xmit_lock, flags);
  72 }
  73
  74 static void iforce_serio_write_wakeup(struct serio *serio)
  75 {
  76         struct iforce *iforce = serio_get_drvdata(serio);
  77
  78         iforce_serial_xmit(iforce);
  79 }
  80
  81 static irqreturn_t iforce_serio_irq(struct serio *serio,
  82                 unsigned char data, unsigned int flags)
  83 {
  84         struct iforce *iforce = serio_get_drvdata(serio);
  85
  86         if (!iforce->pkt) {
  87                 if (data == 0x2b)
  88                         iforce->pkt = 1;
  89                 goto out;
  90         }
  91
  92         if (!iforce->id) {
  93                 if (data > 3 && data != 0xff)
  94                         iforce->pkt = 0;
  95                 else
  96                         iforce->id = data;
  97                 goto out;
  98         }
  99
 100         if (!iforce->len) {
 101                 if (data > IFORCE_MAX_LENGTH) {
 102                         iforce->pkt = 0;
 103                         iforce->id = 0;
 104                 } else {
 105                         iforce->len = data;
 106                 }
 107                 goto out;
 108         }
 109
 110         if (iforce->idx < iforce->len) {
 111                 iforce->csum += iforce->data[iforce->idx++] = data;
 112                 goto out;
 113         }
 114
 115         if (iforce->idx == iforce->len) {
 116                 iforce_process_packet(iforce, (iforce->id << 8) | iforce->idx, iforce->data);
 117                 iforce->pkt = 0;
 118                 iforce->id  = 0;
 119                 iforce->len = 0;
 120                 iforce->idx = 0;
 121                 iforce->csum = 0;
 122         }
 123 out:
 124         return IRQ_HANDLED;
 125 }
 126
 127 static int iforce_serio_connect(struct serio *serio, struct serio_driver *drv)
 128 {
 129         struct iforce *iforce;
 130         int err;
 131
 132         iforce = kzalloc(sizeof(struct iforce), GFP_KERNEL);
 133         if (!iforce)
 134                 return -ENOMEM;
 135
 136         iforce->bus = IFORCE_232;
 137         iforce->serio = serio;
 138
 139         serio_set_drvdata(serio, iforce);
 140
 141         err = serio_open(serio, drv);
 142         if (err)
 143                 goto fail1;
 144
 145         err = iforce_init_device(iforce);
 146         if (err)
 147                 goto fail2;
 148
 149         return 0;
 150
 151  fail2: serio_close(serio);
 152  fail1: serio_set_drvdata(serio, NULL);
 153         kfree(iforce);
 154         return err;
 155 }
 156
 157 static void iforce_serio_disconnect(struct serio *serio)
 158 {
 159         struct iforce *iforce = serio_get_drvdata(serio);
 160
 161         input_unregister_device(iforce->dev);
 162         serio_close(serio);
 163         serio_set_drvdata(serio, NULL);
 164         kfree(iforce);
 165 }
 166
 167 static const struct serio_device_id iforce_serio_ids[] = {
 168         {
 169                 .type   = SERIO_RS232,
 170                 .proto  = SERIO_IFORCE,
 171                 .id     = SERIO_ANY,
 172                 .extra  = SERIO_ANY,
 173         },
 174         { 0 }
 175 };
 176
 177 MODULE_DEVICE_TABLE(serio, iforce_serio_ids);
 178
 179 struct serio_driver iforce_serio_drv = {
 180         .driver         = {
 181                 .name   = "iforce",
 182         },
 183         .description    = "RS232 I-Force joysticks and wheels driver",
 184         .id_table       = iforce_serio_ids,
 185         .write_wakeup   = iforce_serio_write_wakeup,
 186         .interrupt      = iforce_serio_irq,
 187         .connect        = iforce_serio_connect,
 188         .disconnect     = iforce_serio_disconnect,
 189 };